vcmi/server/CGameHandler.cpp

/*
 * CGameHandler.cpp, part of VCMI engine
 *
 * Authors: listed in file AUTHORS in main folder
 *
 * License: GNU General Public License v2.0 or later
 * Full text of license available in license.txt file, in main folder
 *
 */
#include "StdInc.h"

#include "../lib/filesystem/Filesystem.h"
#include "../lib/filesystem/FileInfo.h"
#include "../lib/int3.h"
#include "../lib/mapping/CCampaignHandler.h"
#include "../lib/StartInfo.h"
#include "../lib/CModHandler.h"
#include "../lib/CArtHandler.h"
#include "../lib/CBuildingHandler.h"
#include "../lib/CHeroHandler.h"
#include "../lib/spells/AbilityCaster.h"
#include "../lib/spells/BonusCaster.h"
#include "../lib/spells/CSpellHandler.h"
#include "../lib/spells/ISpellMechanics.h"
#include "../lib/spells/Problem.h"
#include "../lib/CGeneralTextHandler.h"
#include "../lib/CTownHandler.h"
#include "../lib/CCreatureHandler.h"
#include "../lib/CGameState.h"
#include "../lib/CStack.h"
#include "../lib/battle/BattleInfo.h"
#include "../lib/CondSh.h"
#include "../lib/NetPacks.h"
#include "../lib/VCMI_Lib.h"
#include "../lib/mapping/CMap.h"
#include "../lib/mapping/CMapService.h"
#include "../lib/rmg/CMapGenOptions.h"
#include "../lib/VCMIDirs.h"
#include "../lib/ScopeGuard.h"
#include "../lib/CSoundBase.h"
#include "CGameHandler.h"
#include "CVCMIServer.h"
#include "../lib/CCreatureSet.h"
#include "../lib/CThreadHelper.h"
#include "../lib/GameConstants.h"
#include "../lib/registerTypes/RegisterTypes.h"
#include "../lib/serializer/CTypeList.h"
#include "../lib/serializer/Connection.h"
#include "../lib/serializer/Cast.h"

#ifndef _MSC_VER
#include <boost/thread/xtime.hpp>
#endif

#define COMPLAIN_RET_IF(cond, txt) do {if (cond){complain(txt); return;}} while(0)
#define COMPLAIN_RET_FALSE_IF(cond, txt) do {if (cond){complain(txt); return false;}} while(0)
#define COMPLAIN_RET(txt) {complain(txt); return false;}
#define COMPLAIN_RETF(txt, FORMAT) {complain(boost::str(boost::format(txt) % FORMAT)); return false;}

class ServerSpellCastEnvironment : public SpellCastEnvironment
{
public:
	ServerSpellCastEnvironment(CGameHandler * gh);
	~ServerSpellCastEnvironment() = default;
	void sendAndApply(CPackForClient * pack) const override;
	CRandomGenerator & getRandomGenerator() const override;
	void complain(const std::string & problem) const override;
	const CMap * getMap() const override;
	const CGameInfoCallback * getCb() const override;
	bool moveHero(ObjectInstanceID hid, int3 dst, bool teleporting) const override;
	void genericQuery(Query * request, PlayerColor color, std::function<void(const JsonNode &)> callback) const override;
private:
	mutable CGameHandler * gh;
};

namespace spells
{

class ObstacleCasterProxy : public Caster
{
public:
	ObstacleCasterProxy(const PlayerColor owner_, const CGHeroInstance * hero_, const SpellCreatedObstacle * obs_)
		: owner(owner_),
		hero(hero_),
		obs(obs_)
	{
	};

	~ObstacleCasterProxy() = default;

	int32_t getCasterUnitId() const override
	{
		if(hero)
			return hero->getCasterUnitId();
		else
			return -1;
	}

	ui8 getSpellSchoolLevel(const Spell * spell, int * outSelectedSchool = nullptr) const override
	{
		return obs->spellLevel;
	}

	int getEffectLevel(const Spell * spell) const override
	{
		return obs->spellLevel;
	}

	int64_t getSpellBonus(const Spell * spell, int64_t base, const battle::Unit * affectedStack) const override
	{
		if(hero)
			return hero->getSpellBonus(spell, base, affectedStack);
		else
			return base;
	}

	int64_t getSpecificSpellBonus(const Spell * spell, int64_t base) const override
	{
		if(hero)
			return hero->getSpecificSpellBonus(spell, base);
		else
			return base;
	}

	int getEffectPower(const Spell * spell) const override
	{
		return obs->casterSpellPower;
	}

	int getEnchantPower(const Spell * spell) const override
	{
		return obs->casterSpellPower;
	}

	int64_t getEffectValue(const Spell * spell) const override
	{
		if(hero)
			return hero->getEffectValue(spell);
		else
			return 0;
	}

	const PlayerColor getOwner() const override
	{
		return owner;
	}

	void getCasterName(MetaString & text) const override
	{
		logGlobal->error("Unexpected call to ObstacleCasterProxy::getCasterName");
	}

	void getCastDescription(const Spell * spell, const std::vector<const battle::Unit *> & attacked, MetaString & text) const override
	{
		logGlobal->error("Unexpected call to ObstacleCasterProxy::getCastDescription");
	}

	void spendMana(const PacketSender * server, const int spellCost) const override
	{
		logGlobal->error("Unexpected call to ObstacleCasterProxy::spendMana");
	}

private:
	const CGHeroInstance * hero;
	const PlayerColor owner;
	const SpellCreatedObstacle * obs;
};

}//

CondSh<bool> battleMadeAction(false);
CondSh<BattleResult *> battleResult(nullptr);
template <typename T> class CApplyOnGH;

class CBaseForGHApply
{
public:
	virtual bool applyOnGH(CGameHandler * gh, void * pack) const =0;
	virtual ~CBaseForGHApply(){}
	template<typename U> static CBaseForGHApply *getApplier(const U * t=nullptr)
	{
		return new CApplyOnGH<U>();
	}
};

template <typename T> class CApplyOnGH : public CBaseForGHApply
{
public:
	bool applyOnGH(CGameHandler * gh, void * pack) const override
	{
		T *ptr = static_cast<T*>(pack);
		try
		{
			return ptr->applyGh(gh);
		}
		catch(ExceptionNotAllowedAction & e)
		{
			return false;
		}
		catch(...)
		{
			throw;
		}
	}
};

template <>
class CApplyOnGH<CPack> : public CBaseForGHApply
{
public:
	bool applyOnGH(CGameHandler * gh, void * pack) const override
	{
		logGlobal->error("Cannot apply on GH plain CPack!");
		assert(0);
		return false;
	}
};

static inline double distance(int3 a, int3 b)
{
	return std::sqrt((double)(a.x-b.x)*(a.x-b.x) + (a.y-b.y)*(a.y-b.y));
}
static void giveExp(BattleResult &r)
{
	if (r.winner > 1)
	{
		// draw
		return;
	}
	r.exp[0] = 0;
	r.exp[1] = 0;
	for (auto i = r.casualties[!r.winner].begin(); i!=r.casualties[!r.winner].end(); i++)
	{
		r.exp[r.winner] += VLC->creh->creatures.at(i->first)->valOfBonuses(Bonus::STACK_HEALTH) * i->second;
	}
}

static void summonGuardiansHelper(std::vector<BattleHex> & output, const BattleHex & targetPosition, ui8 side, bool targetIsTwoHex) //return hexes for summoning two hex monsters in output, target = unit to guard
{
	int x = targetPosition.getX();
	int y = targetPosition.getY();

	const bool targetIsAttacker = side == BattleSide::ATTACKER;

	if (targetIsAttacker) //handle front guardians, TODO: should we handle situation when units start battle near opposite side of the battlefield? Cannot happen in normal H3...
		BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::RIGHT, false).cloneInDirection(BattleHex::EDir::RIGHT, false), output);
	else
		BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::LEFT, false).cloneInDirection(BattleHex::EDir::LEFT, false), output);

	//guardian spawn locations for four default position cases for attacker and defender, non-default starting location for att and def is handled in first two if's
	if (targetIsAttacker && ((y % 2 == 0) || (x > 1)))
	{
		if (targetIsTwoHex && (y % 2 == 1) && (x == 2)) //handle exceptional case
		{
			BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::TOP_RIGHT, false), output);
			BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::BOTTOM_RIGHT, false), output);
		}
		else
		{	//add back-side guardians for two-hex target, side guardians for one-hex
			BattleHex::checkAndPush(targetPosition.cloneInDirection(targetIsTwoHex ? BattleHex::EDir::TOP_LEFT : BattleHex::EDir::TOP_RIGHT, false), output);
			BattleHex::checkAndPush(targetPosition.cloneInDirection(targetIsTwoHex ? BattleHex::EDir::BOTTOM_LEFT : BattleHex::EDir::BOTTOM_RIGHT, false), output);

			if (!targetIsTwoHex && x > 2) //back guard for one-hex
				BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::LEFT, false), output);
			else if (targetIsTwoHex)//front-side guardians for two-hex target
			{
				BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::RIGHT, false).cloneInDirection(BattleHex::EDir::TOP_RIGHT, false), output);
				BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::RIGHT, false).cloneInDirection(BattleHex::EDir::BOTTOM_RIGHT, false), output);
				if (x > 3) //back guard for two-hex
					BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::LEFT, false).cloneInDirection(BattleHex::EDir::LEFT, false), output);
			}
		}

	}

	else if (!targetIsAttacker && ((y % 2 == 1) || (x < GameConstants::BFIELD_WIDTH - 2)))
	{
		if (targetIsTwoHex && (y % 2 == 0) && (x == GameConstants::BFIELD_WIDTH - 3)) //handle exceptional case... equivalent for above for defender side
		{
			BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::TOP_LEFT, false), output);
			BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::BOTTOM_LEFT, false), output);
		}
		else
		{
			BattleHex::checkAndPush(targetPosition.cloneInDirection(targetIsTwoHex ? BattleHex::EDir::TOP_RIGHT : BattleHex::EDir::TOP_LEFT, false), output);
			BattleHex::checkAndPush(targetPosition.cloneInDirection(targetIsTwoHex ? BattleHex::EDir::BOTTOM_RIGHT : BattleHex::EDir::BOTTOM_LEFT, false), output);

			if (!targetIsTwoHex && x < GameConstants::BFIELD_WIDTH - 3)
				BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::RIGHT, false), output);
			else if (targetIsTwoHex)
			{
				BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::LEFT, false).cloneInDirection(BattleHex::EDir::TOP_LEFT, false), output);
				BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::LEFT, false).cloneInDirection(BattleHex::EDir::BOTTOM_LEFT, false), output);
				if (x < GameConstants::BFIELD_WIDTH - 4)
					BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::RIGHT, false).cloneInDirection(BattleHex::EDir::RIGHT, false), output);
			}
		}
	}

	else if (!targetIsAttacker && y % 2 == 0)
	{
		BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::LEFT, false).cloneInDirection(BattleHex::EDir::TOP_LEFT, false), output);
		BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::LEFT, false).cloneInDirection(BattleHex::EDir::BOTTOM_LEFT, false), output);
	}

	else if (targetIsAttacker && y % 2 == 1)
	{
		BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::RIGHT, false).cloneInDirection(BattleHex::EDir::TOP_RIGHT, false), output);
		BattleHex::checkAndPush(targetPosition.cloneInDirection(BattleHex::EDir::RIGHT, false).cloneInDirection(BattleHex::EDir::BOTTOM_RIGHT, false), output);
	}
}

PlayerStatus PlayerStatuses::operator[](PlayerColor player)
{
	boost::unique_lock<boost::mutex> l(mx);
	if (players.find(player) != players.end())
	{
		return players.at(player);
	}
	else
	{
		throw std::runtime_error("No such player!");
	}
}
void PlayerStatuses::addPlayer(PlayerColor player)
{
	boost::unique_lock<boost::mutex> l(mx);
	players[player];
}

bool PlayerStatuses::checkFlag(PlayerColor player, bool PlayerStatus::*flag)
{
	boost::unique_lock<boost::mutex> l(mx);
	if (players.find(player) != players.end())
	{
		return players[player].*flag;
	}
	else
	{
		throw std::runtime_error("No such player!");
	}
}

void PlayerStatuses::setFlag(PlayerColor player, bool PlayerStatus::*flag, bool val)
{
	boost::unique_lock<boost::mutex> l(mx);
	if (players.find(player) != players.end())
	{
		players[player].*flag = val;
	}
	else
	{
		throw std::runtime_error("No such player!");
	}
	cv.notify_all();
}

template <typename T>
void callWith(std::vector<T> args, std::function<void(T)> fun, ui32 which)
{
	fun(args[which]);
}

void CGameHandler::levelUpHero(const CGHeroInstance * hero, SecondarySkill skill)
{
	changeSecSkill(hero, skill, 1, 0);
	expGiven(hero);
}

void CGameHandler::levelUpHero(const CGHeroInstance * hero)
{
	// required exp for at least 1 lvl-up hasn't been reached
	if (!hero->gainsLevel())
	{
		return;
	}

	// give primary skill
	logGlobal->trace("%s got level %d", hero->name, hero->level);
	auto primarySkill = hero->nextPrimarySkill(getRandomGenerator());

	SetPrimSkill sps;
	sps.id = hero->id;
	sps.which = primarySkill;
	sps.abs = false;
	sps.val = 1;
	sendAndApply(&sps);

	PrepareHeroLevelUp pre;
	pre.heroId = hero->id;
	sendAndApply(&pre);

	HeroLevelUp hlu;
	hlu.player = hero->tempOwner;
	hlu.heroId = hero->id;
	hlu.primskill = primarySkill;
	hlu.skills = pre.skills;

	if (hlu.skills.size() == 0)
	{
		sendAndApply(&hlu);
		levelUpHero(hero);
	}
	else if (hlu.skills.size() == 1)
	{
		sendAndApply(&hlu);
		levelUpHero(hero, pre.skills.front());
	}
	else if (hlu.skills.size() > 1)
	{
		auto levelUpQuery = std::make_shared<CHeroLevelUpDialogQuery>(this, hlu, hero);
		hlu.queryID = levelUpQuery->queryID;
		queries.addQuery(levelUpQuery);
		sendAndApply(&hlu);
		//level up will be called on query reply
	}
}

void CGameHandler::levelUpCommander (const CCommanderInstance * c, int skill)
{
	SetCommanderProperty scp;

	auto hero = dynamic_cast<const CGHeroInstance *>(c->armyObj);
	if (hero)
		scp.heroid = hero->id;
	else
	{
		complain ("Commander is not led by hero!");
		return;
	}

	scp.accumulatedBonus.subtype = 0;
	scp.accumulatedBonus.additionalInfo = 0;
	scp.accumulatedBonus.duration = Bonus::PERMANENT;
	scp.accumulatedBonus.turnsRemain = 0;
	scp.accumulatedBonus.source = Bonus::COMMANDER;
	scp.accumulatedBonus.valType = Bonus::BASE_NUMBER;
	if (skill <= ECommander::SPELL_POWER)
	{
		scp.which = SetCommanderProperty::BONUS;

		auto difference = [](std::vector< std::vector <ui8> > skillLevels, std::vector <ui8> secondarySkills, int skill)->int
		{
			int s = std::min (skill, (int)ECommander::SPELL_POWER); //spell power level controls also casts and resistance
			return skillLevels.at(skill).at(secondarySkills.at(s)) - (secondarySkills.at(s) ? skillLevels.at(skill).at(secondarySkills.at(s)-1) : 0);
		};

		switch (skill)
		{
			case ECommander::ATTACK:
				scp.accumulatedBonus.type = Bonus::PRIMARY_SKILL;
				scp.accumulatedBonus.subtype = PrimarySkill::ATTACK;
				break;
			case ECommander::DEFENSE:
				scp.accumulatedBonus.type = Bonus::PRIMARY_SKILL;
				scp.accumulatedBonus.subtype = PrimarySkill::DEFENSE;
				break;
			case ECommander::HEALTH:
				scp.accumulatedBonus.type = Bonus::STACK_HEALTH;
				scp.accumulatedBonus.valType = Bonus::PERCENT_TO_BASE;
				break;
			case ECommander::DAMAGE:
				scp.accumulatedBonus.type = Bonus::CREATURE_DAMAGE;
				scp.accumulatedBonus.subtype = 0;
				scp.accumulatedBonus.valType = Bonus::PERCENT_TO_BASE;
				break;
			case ECommander::SPEED:
				scp.accumulatedBonus.type = Bonus::STACKS_SPEED;
				break;
			case ECommander::SPELL_POWER:
				scp.accumulatedBonus.type = Bonus::MAGIC_RESISTANCE;
				scp.accumulatedBonus.val = difference (VLC->creh->skillLevels, c->secondarySkills, ECommander::RESISTANCE);
				sendAndApply (&scp); //additional pack
				scp.accumulatedBonus.type = Bonus::CREATURE_SPELL_POWER;
				scp.accumulatedBonus.val = difference (VLC->creh->skillLevels, c->secondarySkills, ECommander::SPELL_POWER) * 100; //like hero with spellpower = ability level
				sendAndApply (&scp); //additional pack
				scp.accumulatedBonus.type = Bonus::CASTS;
				scp.accumulatedBonus.val = difference (VLC->creh->skillLevels, c->secondarySkills, ECommander::CASTS);
				sendAndApply (&scp); //additional pack
				scp.accumulatedBonus.type = Bonus::CREATURE_ENCHANT_POWER; //send normally
				break;
		}

		scp.accumulatedBonus.val = difference (VLC->creh->skillLevels, c->secondarySkills, skill);
		sendAndApply (&scp);

		scp.which = SetCommanderProperty::SECONDARY_SKILL;
		scp.additionalInfo = skill;
		scp.amount = c->secondarySkills.at(skill) + 1;
		sendAndApply (&scp);
	}
	else if (skill >= 100)
	{
		scp.which = SetCommanderProperty::SPECIAL_SKILL;
		scp.accumulatedBonus = *VLC->creh->skillRequirements.at(skill-100).first;
		scp.additionalInfo = skill; //unnormalized
		sendAndApply (&scp);
	}
	expGiven(hero);
}

void CGameHandler::levelUpCommander(const CCommanderInstance * c)
{
	if (!c->gainsLevel())
	{
		return;
	}
	CommanderLevelUp clu;

	auto hero = dynamic_cast<const CGHeroInstance *>(c->armyObj);
	if(hero)
	{
		clu.heroId = hero->id;
		clu.player = hero->tempOwner;
	}
	else
	{
		complain ("Commander is not led by hero!");
		return;
	}

	//picking sec. skills for choice

	for (int i = 0; i <= ECommander::SPELL_POWER; ++i)
	{
		if (c->secondarySkills.at(i) < ECommander::MAX_SKILL_LEVEL)
			clu.skills.push_back(i);
	}
	int i = 100;
	for (auto specialSkill : VLC->creh->skillRequirements)
	{
		if (c->secondarySkills.at(specialSkill.second.first) == ECommander::MAX_SKILL_LEVEL
			&&  c->secondarySkills.at(specialSkill.second.second) == ECommander::MAX_SKILL_LEVEL
			&&  !vstd::contains (c->specialSKills, i))
			clu.skills.push_back (i);
		++i;
	}
	int skillAmount = clu.skills.size();

	if (!skillAmount)
	{
		sendAndApply(&clu);
		levelUpCommander(c);
	}
	else if (skillAmount == 1  ||  hero->tempOwner == PlayerColor::NEUTRAL) //choose skill automatically
	{
		sendAndApply(&clu);
		levelUpCommander(c, *RandomGeneratorUtil::nextItem(clu.skills, getRandomGenerator()));
	}
	else if (skillAmount > 1) //apply and ask for secondary skill
	{
		auto commanderLevelUp = std::make_shared<CCommanderLevelUpDialogQuery>(this, clu, hero);
		clu.queryID = commanderLevelUp->queryID;
		queries.addQuery(commanderLevelUp);
		sendAndApply(&clu);
	}
}

void CGameHandler::expGiven(const CGHeroInstance *hero)
{
	if (hero->gainsLevel())
		levelUpHero(hero);
	else if (hero->commander && hero->commander->gainsLevel())
		levelUpCommander(hero->commander);

	//if (hero->commander && hero->level > hero->commander->level && hero->commander->gainsLevel())
// 		levelUpCommander(hero->commander);
// 	else
// 		levelUpHero(hero);
}

void CGameHandler::changePrimSkill(const CGHeroInstance * hero, PrimarySkill::PrimarySkill which, si64 val, bool abs)
{
	if (which == PrimarySkill::EXPERIENCE) // Check if scenario limit reached
	{
		if (gs->map->levelLimit != 0)
		{
			TExpType expLimit = VLC->heroh->reqExp(gs->map->levelLimit);
			TExpType resultingExp = abs ? val : hero->exp + val;
			if (resultingExp > expLimit)
			{
				// set given experience to max possible, but don't decrease if hero already over top
				abs = true;
				val = std::max(expLimit, hero->exp);

				InfoWindow iw;
				iw.player = hero->tempOwner;
				iw.text.addTxt(MetaString::GENERAL_TXT, 1); //can gain no more XP
				iw.text.addReplacement(hero->name);
				sendAndApply(&iw);
			}
		}
	}

	SetPrimSkill sps;
	sps.id = hero->id;
	sps.which = which;
	sps.abs = abs;
	sps.val = val;
	sendAndApply(&sps);

	//only for exp - hero may level up
	if (which == PrimarySkill::EXPERIENCE)
	{
		if (hero->commander && hero->commander->alive)
		{
			//FIXME: trim experience according to map limit?
			SetCommanderProperty scp;
			scp.heroid = hero->id;
			scp.which = SetCommanderProperty::EXPERIENCE;
			scp.amount = val;
			sendAndApply (&scp);
			CBonusSystemNode::treeHasChanged();
		}

		expGiven(hero);
	}
}

void CGameHandler::changeSecSkill(const CGHeroInstance * hero, SecondarySkill which, int val, bool abs)
{
	if(!hero)
	{
		logGlobal->error("changeSecSkill provided no hero");
		return;
	}
	SetSecSkill sss;
	sss.id = hero->id;
	sss.which = which;
	sss.val = val;
	sss.abs = abs;
	sendAndApply(&sss);

	if (which == SecondarySkill::WISDOM)
	{
		if (hero->visitedTown)
			giveSpells(hero->visitedTown, hero);
	}
}

void CGameHandler::endBattle(int3 tile, const CGHeroInstance *hero1, const CGHeroInstance *hero2)
{
	LOG_TRACE(logGlobal);

	//Fill BattleResult structure with exp info
	giveExp(*battleResult.data);

	if (battleResult.get()->result == BattleResult::NORMAL) // give 500 exp for defeating hero, unless he escaped
	{
		if (hero1)
			battleResult.data->exp[1] += 500;
		if (hero2)
			battleResult.data->exp[0] += 500;
	}

	if (hero1)
		battleResult.data->exp[0] = hero1->calculateXp(battleResult.data->exp[0]);//scholar skill
	if (hero2)
		battleResult.data->exp[1] = hero2->calculateXp(battleResult.data->exp[1]);

	const CArmedInstance *bEndArmy1 = gs->curB->sides.at(0).armyObject;
	const CArmedInstance *bEndArmy2 = gs->curB->sides.at(1).armyObject;
	const BattleResult::EResult result = battleResult.get()->result;

	auto findBattleQuery = [this]() -> std::shared_ptr<CBattleQuery>
	{
		for (auto &q : queries.allQueries())
		{
			if (auto bq = std::dynamic_pointer_cast<CBattleQuery>(q))
				if (bq->bi == gs->curB)
					return bq;
		}
		return std::shared_ptr<CBattleQuery>();
	};

	auto battleQuery = findBattleQuery();
	if (!battleQuery)
	{
		logGlobal->error("Cannot find battle query!");
	}
	if (battleQuery != queries.topQuery(gs->curB->sides[0].color))
		complain("Player " + boost::lexical_cast<std::string>(gs->curB->sides[0].color) + " although in battle has no battle query at the top!");

	battleQuery->result = boost::make_optional(*battleResult.data);

	//Check how many battle queries were created (number of players blocked by battle)
	const int queriedPlayers = battleQuery ? boost::count(queries.allQueries(), battleQuery) : 0;
	finishingBattle = make_unique<FinishingBattleHelper>(battleQuery, queriedPlayers);


	CasualtiesAfterBattle cab1(bEndArmy1, gs->curB), cab2(bEndArmy2, gs->curB); //calculate casualties before deleting battle

	ChangeSpells cs; //for Eagle Eye

	if (finishingBattle->winnerHero)
	{
		if (int eagleEyeLevel = finishingBattle->winnerHero->valOfBonuses(Bonus::SECONDARY_SKILL_VAL2, SecondarySkill::EAGLE_EYE))
		{
			double eagleEyeChance = finishingBattle->winnerHero->valOfBonuses(Bonus::SECONDARY_SKILL_PREMY, SecondarySkill::EAGLE_EYE);
			for (const CSpell *sp : gs->curB->sides.at(!battleResult.data->winner).usedSpellsHistory)
				if (sp->level <= eagleEyeLevel && !finishingBattle->winnerHero->spellbookContainsSpell(sp->id) && getRandomGenerator().nextInt(99) < eagleEyeChance)
					cs.spells.insert(sp->id);
		}
	}


	std::vector<const CArtifactInstance *> arts; //display them in window

	if (result == BattleResult::NORMAL && finishingBattle->winnerHero)
	{
		auto sendMoveArtifact = [&](const CArtifactInstance *art, MoveArtifact *ma)
		{
			arts.push_back(art);
			ma->dst = ArtifactLocation(finishingBattle->winnerHero, art->firstAvailableSlot(finishingBattle->winnerHero));
			sendAndApply(ma);
		};
		if (finishingBattle->loserHero)
		{
			//TODO: wrap it into a function, somehow (boost::variant -_-)
			auto artifactsWorn = finishingBattle->loserHero->artifactsWorn;
			for (auto artSlot : artifactsWorn)
			{
				MoveArtifact ma;
				ma.src = ArtifactLocation(finishingBattle->loserHero, artSlot.first);
				const CArtifactInstance * art =  ma.src.getArt();
				if (art && !art->artType->isBig() &&
				    art->artType->id != ArtifactID::SPELLBOOK)
						// don't move war machines or locked arts (spellbook)
				{
					sendMoveArtifact(art, &ma);
				}
			}
			while(!finishingBattle->loserHero->artifactsInBackpack.empty())
			{
				//we assume that no big artifacts can be found
				MoveArtifact ma;
				ma.src = ArtifactLocation(finishingBattle->loserHero,
					ArtifactPosition(GameConstants::BACKPACK_START)); //backpack automatically shifts arts to beginning
				const CArtifactInstance * art =  ma.src.getArt();
				if (art->artType->id != ArtifactID::GRAIL) //grail may not be won
				{
					sendMoveArtifact(art, &ma);
				}
			}
			if (finishingBattle->loserHero->commander) //TODO: what if commanders belong to no hero?
			{
				artifactsWorn = finishingBattle->loserHero->commander->artifactsWorn;
				for (auto artSlot : artifactsWorn)
				{
					MoveArtifact ma;
					ma.src = ArtifactLocation(finishingBattle->loserHero->commander.get(), artSlot.first);
					const CArtifactInstance * art =  ma.src.getArt();
					if (art && !art->artType->isBig())
					{
						sendMoveArtifact(art, &ma);
					}
				}
			}
		}
		for (auto armySlot : gs->curB->battleGetArmyObject(!battleResult.data->winner)->stacks)
		{
			auto artifactsWorn = armySlot.second->artifactsWorn;
			for (auto artSlot : artifactsWorn)
			{
				MoveArtifact ma;
				ma.src = ArtifactLocation(armySlot.second, artSlot.first);
				const CArtifactInstance * art =  ma.src.getArt();
				if (art && !art->artType->isBig())
				{
					sendMoveArtifact(art, &ma);
				}
			}
		}
	}

	sendAndApply(battleResult.data); //after this point casualties objects are destroyed

	if (arts.size()) //display loot
	{
		InfoWindow iw;
		iw.player = finishingBattle->winnerHero->tempOwner;

		iw.text.addTxt (MetaString::GENERAL_TXT, 30); //You have captured enemy artifact

		for (auto art : arts) //TODO; separate function to display loot for various ojects?
		{
			iw.components.push_back(Component(
				Component::ARTIFACT, art->artType->id,
				art->artType->id == ArtifactID::SPELL_SCROLL? art->getGivenSpellID() : 0, 0));
			if (iw.components.size() >= 14)
			{
				sendAndApply(&iw);
				iw.components.clear();
			}
		}
		if (iw.components.size())
		{
			sendAndApply(&iw);
		}
	}
	//Eagle Eye secondary skill handling
	if (!cs.spells.empty())
	{
		cs.learn = 1;
		cs.hid = finishingBattle->winnerHero->id;

		InfoWindow iw;
		iw.player = finishingBattle->winnerHero->tempOwner;
		iw.text.addTxt(MetaString::GENERAL_TXT, 221); //Through eagle-eyed observation, %s is able to learn %s
		iw.text.addReplacement(finishingBattle->winnerHero->name);

		std::ostringstream names;
		for (int i = 0; i < cs.spells.size(); i++)
		{
			names << "%s";
			if (i < cs.spells.size() - 2)
				names << ", ";
			else if (i < cs.spells.size() - 1)
				names << "%s";
		}
		names << ".";

		iw.text.addReplacement(names.str());

		auto it = cs.spells.begin();
		for (int i = 0; i < cs.spells.size(); i++, it++)
		{
			iw.text.addReplacement(MetaString::SPELL_NAME, it->toEnum());
			if (i == cs.spells.size() - 2) //we just added pre-last name
				iw.text.addReplacement(MetaString::GENERAL_TXT, 141); // " and "
			iw.components.push_back(Component(Component::SPELL, *it, 0, 0));
		}

		sendAndApply(&iw);
		sendAndApply(&cs);
	}

	cab1.updateArmy(this);
	cab2.updateArmy(this); //take casualties after battle is deleted

	//if one hero has lost we will erase him
	if (battleResult.data->winner!=0 && hero1)
	{
		RemoveObject ro(hero1->id);
		sendAndApply(&ro);
	}
	if (battleResult.data->winner!=1 && hero2)
	{
		auto town = hero2->visitedTown;
		RemoveObject ro(hero2->id);
		sendAndApply(&ro);

		if (town && !town->garrisonHero) // TODO: that must be called from CGHeroInstance or CGTownInstance
			town->battleFinished(hero1, *battleResult.get());
	}

	//give exp
	if (battleResult.data->exp[0] && hero1 && battleResult.get()->winner == 0)
		changePrimSkill(hero1, PrimarySkill::EXPERIENCE, battleResult.data->exp[0]);
	else if (battleResult.data->exp[1] && hero2 && battleResult.get()->winner == 1)
		changePrimSkill(hero2, PrimarySkill::EXPERIENCE, battleResult.data->exp[1]);

	queries.popIfTop(battleQuery);

	//--> continuation (battleAfterLevelUp) occurs after level-up queries are handled or on removing query (above)
}

void CGameHandler::battleAfterLevelUp(const BattleResult &result)
{
	LOG_TRACE(logGlobal);


	finishingBattle->remainingBattleQueriesCount--;
	logGlobal->trace("Decremented queries count to %d", finishingBattle->remainingBattleQueriesCount);

	if (finishingBattle->remainingBattleQueriesCount > 0)
		//Battle results will be handled when all battle queries are closed
		return;

	//TODO consider if we really want it to work like above. ATM each player as unblocked as soon as possible
	// but the battle consequences are applied after final player is unblocked. Hard to abuse...
	// Still, it looks like a hole.

	// Necromancy if applicable.
	const CStackBasicDescriptor raisedStack = finishingBattle->winnerHero ? finishingBattle->winnerHero->calculateNecromancy(*battleResult.data) : CStackBasicDescriptor();
	// Give raised units to winner and show dialog, if any were raised,
	// units will be given after casualties are taken
	const SlotID necroSlot = raisedStack.type ? finishingBattle->winnerHero->getSlotFor(raisedStack.type) : SlotID();

	if (necroSlot != SlotID())
	{
		finishingBattle->winnerHero->showNecromancyDialog(raisedStack, getRandomGenerator());
		addToSlot(StackLocation(finishingBattle->winnerHero, necroSlot), raisedStack.type, raisedStack.count);
	}

	BattleResultsApplied resultsApplied;
	resultsApplied.player1 = finishingBattle->victor;
	resultsApplied.player2 = finishingBattle->loser;
	sendAndApply(&resultsApplied);

	setBattle(nullptr);

	if (visitObjectAfterVictory && result.winner==0 && !finishingBattle->winnerHero->stacks.empty())
	{
		logGlobal->trace("post-victory visit");
		visitObjectOnTile(*getTile(finishingBattle->winnerHero->getPosition()), finishingBattle->winnerHero);
	}
	visitObjectAfterVictory = false;

	//handle victory/loss of engaged players
	std::set<PlayerColor> playerColors = {finishingBattle->loser, finishingBattle->victor};
	checkVictoryLossConditions(playerColors);

	if (result.result == BattleResult::SURRENDER || result.result == BattleResult::ESCAPE) //loser has escaped or surrendered
	{
		SetAvailableHeroes sah;
		sah.player = finishingBattle->loser;
		sah.hid[0] = finishingBattle->loserHero->subID;
		if (result.result == BattleResult::ESCAPE) //retreat
		{
			sah.army[0].clear();
			sah.army[0].setCreature(SlotID(0), finishingBattle->loserHero->type->initialArmy.at(0).creature, 1);
		}

		if (const CGHeroInstance *another =  getPlayer(finishingBattle->loser)->availableHeroes.at(0))
			sah.hid[1] = another->subID;
		else
			sah.hid[1] = -1;

		sendAndApply(&sah);
	}
	if (result.winner != 2 && finishingBattle->winnerHero && finishingBattle->winnerHero->stacks.empty())
	{
		RemoveObject ro(finishingBattle->winnerHero->id);
		sendAndApply(&ro);

		if (VLC->modh->settings.WINNING_HERO_WITH_NO_TROOPS_RETREATS)
		{
			SetAvailableHeroes sah;
			sah.player = finishingBattle->victor;
			sah.hid[0] = finishingBattle->winnerHero->subID;
			sah.army[0].clear();
			sah.army[0].setCreature(SlotID(0), finishingBattle->winnerHero->type->initialArmy.at(0).creature, 1);

			if (const CGHeroInstance *another =  getPlayer(finishingBattle->victor)->availableHeroes.at(0))
				sah.hid[1] = another->subID;
			else
				sah.hid[1] = -1;

			sendAndApply(&sah);
		}
	}
}

void CGameHandler::makeAttack(const CStack * attacker, const CStack * defender, int distance, BattleHex targetHex, bool first, bool ranged, bool counter)
{
	if(first && !counter)
		handleAttackBeforeCasting(ranged, attacker, defender);

	FireShieldInfo fireShield;
	BattleAttack bat;
	bat.stackAttacking = attacker->unitId();

	std::shared_ptr<battle::CUnitState> attackerState = attacker->acquireState();

	if(ranged)
		bat.flags |= BattleAttack::SHOT;
	if(counter)
		bat.flags |= BattleAttack::COUNTER;

	const int attackerLuck = attacker->LuckVal();

	auto sideHeroBlocksLuck = [](const SideInBattle &side){ return NBonus::hasOfType(side.hero, Bonus::BLOCK_LUCK); };

	if (!vstd::contains_if (gs->curB->sides, sideHeroBlocksLuck))
	{
		if (attackerLuck > 0  && getRandomGenerator().nextInt(23) < attackerLuck)
		{
			bat.flags |= BattleAttack::LUCKY;
		}
		if (VLC->modh->settings.data["hardcodedFeatures"]["NEGATIVE_LUCK"].Bool()) // negative luck enabled
		{
			if (attackerLuck < 0 && getRandomGenerator().nextInt(23) < abs(attackerLuck))
			{
				bat.flags |= BattleAttack::UNLUCKY;
			}
		}
	}

	if (getRandomGenerator().nextInt(99) < attacker->valOfBonuses(Bonus::DOUBLE_DAMAGE_CHANCE))
	{
		bat.flags |= BattleAttack::DEATH_BLOW;
	}

	if (attacker->getCreature()->idNumber == CreatureID::BALLISTA)
	{
		const CGHeroInstance * owner = gs->curB->getHero(attacker->owner);
		int chance = owner->valOfBonuses(Bonus::SECONDARY_SKILL_PREMY, SecondarySkill::ARTILLERY);
		if (chance > getRandomGenerator().nextInt(99))
		{
			bat.flags |= BattleAttack::BALLISTA_DOUBLE_DMG;
		}
	}
	// only primary target
	if(defender->alive())
		applyBattleEffects(bat, attackerState, fireShield, defender, distance, false);

	//multiple-hex normal attack
	std::set<const CStack*> attackedCreatures = gs->curB->getAttackedCreatures(attacker, targetHex, bat.shot()); //creatures other than primary target

	for(const CStack * stack : attackedCreatures)
	{
		if(stack != defender && stack->alive()) //do not hit same stack twice
			applyBattleEffects(bat, attackerState, fireShield, stack, distance, true);
	}

	const std::shared_ptr<Bonus> bonus = attacker->getBonusLocalFirst(Selector::type(Bonus::SPELL_LIKE_ATTACK));
	if(bonus && ranged) //TODO: make it work in melee?
	{
		//this is need for displaying hit animation
		bat.flags |= BattleAttack::SPELL_LIKE;
		bat.spellID = SpellID(bonus->subtype);

		//TODO: should spell override creature`s projectile?

		battle::Target target;
		target.emplace_back(defender);

		auto attackedCreatures = SpellID(bonus->subtype).toSpell()->getAffectedStacks(gs->curB, spells::Mode::SPELL_LIKE_ATTACK, attacker, bonus->val, target);

		//TODO: get exact attacked hex for defender

		for(const CStack * stack : attackedCreatures)
		{
			if(stack != defender && stack->alive()) //do not hit same stack twice
			{
				applyBattleEffects(bat, attackerState, fireShield, stack, distance, true);
			}
		}

		//now add effect info for all attacked stacks
		for (BattleStackAttacked & bsa : bat.bsa)
		{
			if (bsa.attackerID == attacker->ID) //this is our attack and not f.e. fire shield
			{
				//this is need for displaying affect animation
				bsa.flags |= BattleStackAttacked::SPELL_EFFECT;
				bsa.spellID = SpellID(bonus->subtype);
			}
		}
	}

	attackerState->afterAttack(ranged, counter);

	{
		UnitChanges info(attackerState->unitId(), UnitChanges::EOperation::RESET_STATE);
		attackerState->save(info.data);
		bat.attackerChanges.changedStacks.push_back(info);
	}

	sendAndApply(&bat);

	if(!fireShield.empty())
	{
		//todo: this should be "virtual" spell instead, we only need fire spell school bonus here
		const CSpell * fireShieldSpell = SpellID(SpellID::FIRE_SHIELD).toSpell();
		StacksInjured pack;
		int64_t totalDamage = 0;

		for(const auto & item : fireShield)
		{
			const CStack * actor = item.first;
			int64_t rawDamage = item.second;

			const CGHeroInstance * actorOwner = gs->curB->getHero(actor->owner);

			if(actorOwner)
			{
				rawDamage = fireShieldSpell->adjustRawDamage(actorOwner, attacker, rawDamage);
			}
			else
			{
				rawDamage = fireShieldSpell->adjustRawDamage(actor, attacker, rawDamage);
			}

			totalDamage+=rawDamage;
			//FIXME: add custom effect on actor
		}

		BattleStackAttacked bsa;

		bsa.stackAttacked = attacker->ID; //invert
		bsa.attackerID = uint32_t(-1);
		bsa.flags |= BattleStackAttacked::EFFECT;
		bsa.effect = 11;
		bsa.damageAmount = totalDamage;
		attacker->prepareAttacked(bsa, getRandomGenerator());

		pack.stacks.push_back(bsa);

		sendAndApply(&pack);
	}

	handleAfterAttackCasting(ranged, attacker, defender);
}
void CGameHandler::applyBattleEffects(BattleAttack & bat, std::shared_ptr<battle::CUnitState> attackerState, FireShieldInfo & fireShield, const CStack * def, int distance, bool secondary)
{
	BattleStackAttacked bsa;
	if(secondary)
		bsa.flags |= BattleStackAttacked::SECONDARY; //all other targets do not suffer from spells & spell-like abilities
	bsa.attackerID = attackerState->unitId();
	bsa.stackAttacked = def->unitId();
	{
		BattleAttackInfo bai(attackerState.get(), def, bat.shot());
		bai.chargedFields = distance;

		if(bat.deathBlow())
			bai.additiveBonus += 1.0;

		if(bat.ballistaDoubleDmg())
			bai.additiveBonus += 1.0;

		if(bat.lucky())
			bai.additiveBonus += 1.0;

		//unlucky hit, used only if negative luck is enabled
		if(bat.unlucky())
			bai.additiveBonus -= 0.5; // FIXME: how bad (and luck in general) should work with following bonuses?

		auto range = gs->curB->calculateDmgRange(bai);
		bsa.damageAmount = gs->curB->getActualDamage(range, attackerState->getCount(), getRandomGenerator());
		CStack::prepareAttacked(bsa, getRandomGenerator(), bai.defender->acquireState()); //calculate casualties
	}

	auto addLifeDrain = [&](int64_t & toHeal, EHealLevel level, EHealPower power)
	{
		attackerState->heal(toHeal, level, power);

		if(toHeal > 0)
		{
			CustomEffectInfo customEffect;
			customEffect.sound = soundBase::DRAINLIF;
			customEffect.effect = 52;
			customEffect.stack = attackerState->unitId();
			bat.customEffects.push_back(customEffect);

			MetaString text;
			attackerState->addText(text, MetaString::GENERAL_TXT, 361);
			attackerState->addNameReplacement(text, false);
			text.addReplacement(toHeal);
			def->addNameReplacement(text, true);
			bat.battleLog.push_back(text);
		}
	};

	//life drain handling
	if(attackerState->hasBonusOfType(Bonus::LIFE_DRAIN) && def->isLiving())
	{
		int64_t toHeal = bsa.damageAmount * attackerState->valOfBonuses(Bonus::LIFE_DRAIN) / 100;

		if(toHeal > 0)
			addLifeDrain(toHeal, EHealLevel::RESURRECT, EHealPower::PERMANENT);
	}

	//soul steal handling
	if(attackerState->hasBonusOfType(Bonus::SOUL_STEAL) && def->isLiving())
	{
		//we can have two bonuses - one with subtype 0 and another with subtype 1
		//try to use permanent first, use only one of two
		for(si32 subtype = 1; subtype >= 0; subtype--)
		{
			if(attackerState->hasBonusOfType(Bonus::SOUL_STEAL, subtype))
			{
				int64_t toHeal = bsa.killedAmount * attackerState->valOfBonuses(Bonus::SOUL_STEAL, subtype) * attackerState->MaxHealth();
				addLifeDrain(toHeal, EHealLevel::OVERHEAL, ((subtype == 0) ? EHealPower::ONE_BATTLE : EHealPower::PERMANENT));
				break;
			}
		}
	}
	bat.bsa.push_back(bsa); //add this stack to the list of victims after drain life has been calculated

	//fire shield handling
	if(!bat.shot() && !def->isClone() &&
		def->hasBonusOfType(Bonus::FIRE_SHIELD) && !attackerState->hasBonusOfType(Bonus::FIRE_IMMUNITY))
	{
		//TODO: use damage with bonus but without penalties
		auto fireShieldDamage = (std::min<int64_t>(def->getAvailableHealth(), bsa.damageAmount) * def->valOfBonuses(Bonus::FIRE_SHIELD)) / 100;
		fireShield.push_back(std::make_pair(def, fireShieldDamage));
	}
}

void CGameHandler::handleClientDisconnection(std::shared_ptr<CConnection> c)
{
	for(auto playerConns : connections)
	{
		for(auto conn : playerConns.second)
		{
			if(lobby->state != EServerState::SHUTDOWN && conn == c)
			{
				vstd::erase_if_present(playerConns.second, conn);
				if(playerConns.second.size())
					continue;
				PlayerCheated pc;
				pc.player = playerConns.first;
				pc.losingCheatCode = true;
				sendAndApply(&pc);
				checkVictoryLossConditionsForPlayer(playerConns.first);
			}
		}
	}
}

void CGameHandler::handleReceivedPack(CPackForServer * pack)
{
	//prepare struct informing that action was applied
	auto sendPackageResponse = [&](bool succesfullyApplied)
	{
		PackageApplied applied;
		applied.player = pack->player;
		applied.result = succesfullyApplied;
		applied.packType = typeList.getTypeID(pack);
		applied.requestID = pack->requestID;
		pack->c->sendPack(&applied);
	};

	CBaseForGHApply * apply = applier->getApplier(typeList.getTypeID(pack)); //and appropriate applier object
	if(isBlockedByQueries(pack, pack->player))
	{
		sendPackageResponse(false);
	}
	else if(apply)
	{
		const bool result = apply->applyOnGH(this, pack);
		if(result)
			logGlobal->trace("Message %s successfully applied!", typeid(*pack).name());
		else
			complain((boost::format("Got false in applying %s... that request must have been fishy!")
				% typeid(*pack).name()).str());

		sendPackageResponse(true);
	}
	else
	{
		logGlobal->error("Message cannot be applied, cannot find applier (unregistered type)!");
		sendPackageResponse(false);
	}

	vstd::clear_pointer(pack);
}

int CGameHandler::moveStack(int stack, BattleHex dest)
{
	int ret = 0;

	const CStack *curStack = gs->curB->battleGetStackByID(stack),
		*stackAtEnd = gs->curB->battleGetStackByPos(dest);

	assert(curStack);
	assert(dest < GameConstants::BFIELD_SIZE);

	if (gs->curB->tacticDistance)
	{
		assert(gs->curB->isInTacticRange(dest));
	}

	auto start = curStack->getPosition();
	if (start == dest)
		return 0;

	//initing necessary tables
	auto accessibility = getAccesibility(curStack);

	//shifting destination (if we have double wide stack and we can occupy dest but not be exactly there)
	if(!stackAtEnd && curStack->doubleWide() && !accessibility.accessible(dest, curStack))
	{
		BattleHex shifted = dest.cloneInDirection(curStack->destShiftDir(), false);

		if(accessibility.accessible(shifted, curStack))
			dest = shifted;
	}

	if((stackAtEnd && stackAtEnd!=curStack && stackAtEnd->alive()) || !accessibility.accessible(dest, curStack))
	{
		complain("Given destination is not accessible!");
		return 0;
	}

	bool canUseGate = false;
	auto dbState = gs->curB->si.gateState;
	if(battleGetSiegeLevel() > 0 && curStack->side == BattleSide::DEFENDER &&
		dbState != EGateState::DESTROYED &&
		dbState != EGateState::BLOCKED)
	{
		canUseGate = true;
	}

	std::pair< std::vector<BattleHex>, int > path = gs->curB->getPath(start, dest, curStack);

	ret = path.second;

	int creSpeed = gs->curB->tacticDistance ? GameConstants::BFIELD_SIZE : curStack->Speed(0, true);

	auto isGateDrawbridgeHex = [&](BattleHex hex) -> bool
	{
		if (gs->curB->town->subID == ETownType::FORTRESS && hex == ESiegeHex::GATE_BRIDGE)
			return true;
		if (hex == ESiegeHex::GATE_OUTER)
			return true;
		if (hex == ESiegeHex::GATE_INNER)
			return true;

		return false;
	};

	auto occupyGateDrawbridgeHex = [&](BattleHex hex) -> bool
	{
		if (isGateDrawbridgeHex(hex))
			return true;

		if (curStack->doubleWide())
		{
			BattleHex otherHex = curStack->occupiedHex(hex);
			if (otherHex.isValid() && isGateDrawbridgeHex(otherHex))
				return true;
		}

		return false;
	};

	if (curStack->hasBonusOfType(Bonus::FLYING))
	{
		if (path.second <= creSpeed && path.first.size() > 0)
		{
			if (canUseGate && dbState != EGateState::OPENED &&
				occupyGateDrawbridgeHex(dest))
			{
				BattleUpdateGateState db;
				db.state = EGateState::OPENED;
				sendAndApply(&db);
			}

			//inform clients about move
			BattleStackMoved sm;
			sm.stack = curStack->ID;
			std::vector<BattleHex> tiles;
			tiles.push_back(path.first[0]);
			sm.tilesToMove = tiles;
			sm.distance = path.second;
			sm.teleporting = false;
			sendAndApply(&sm);
		}
	}
	else //for non-flying creatures
	{
		std::vector<BattleHex> tiles;
		const int tilesToMove = std::max((int)(path.first.size() - creSpeed), 0);
		int v = path.first.size()-1;
		path.first.push_back(start);

		// check if gate need to be open or closed at some point
		BattleHex openGateAtHex, gateMayCloseAtHex;
		if (canUseGate)
		{
			for (int i = path.first.size()-1; i >= 0; i--)
			{
				auto needOpenGates = [&](BattleHex hex) -> bool
				{
					if (gs->curB->town->subID == ETownType::FORTRESS && hex == ESiegeHex::GATE_BRIDGE)
						return true;
					if (hex == ESiegeHex::GATE_BRIDGE && i-1 >= 0 && path.first[i-1] == ESiegeHex::GATE_OUTER)
						return true;
					else if (hex == ESiegeHex::GATE_OUTER || hex == ESiegeHex::GATE_INNER)
						return true;

					return false;
				};

				auto hex = path.first[i];
				if (!openGateAtHex.isValid() && dbState != EGateState::OPENED)
				{
					if (needOpenGates(hex))
						openGateAtHex = path.first[i+1];

					//TODO we need find batter way to handle double-wide stacks
					//currently if only second occupied stack part is standing on gate / bridge hex then stack will start to wait for bridge to lower before it's needed. Though this is just a visual bug.
					if (curStack->doubleWide())
					{
						BattleHex otherHex = curStack->occupiedHex(hex);
						if (otherHex.isValid() && needOpenGates(otherHex))
							openGateAtHex = path.first[i+2];
					}

					//gate may be opened and then closed during stack movement, but not other way around
					if (openGateAtHex.isValid())
						dbState = EGateState::OPENED;
				}

				if (!gateMayCloseAtHex.isValid() && dbState != EGateState::CLOSED)
				{
					if (hex == ESiegeHex::GATE_INNER && i-1 >= 0 && path.first[i-1] != ESiegeHex::GATE_OUTER)
					{
						gateMayCloseAtHex = path.first[i-1];
					}
					if (gs->curB->town->subID == ETownType::FORTRESS)
					{
						if (hex == ESiegeHex::GATE_BRIDGE && i-1 >= 0 && path.first[i-1] != ESiegeHex::GATE_OUTER)
						{
							gateMayCloseAtHex = path.first[i-1];
						}
						else if (hex == ESiegeHex::GATE_OUTER && i-1 >= 0 &&
							path.first[i-1] != ESiegeHex::GATE_INNER &&
							path.first[i-1] != ESiegeHex::GATE_BRIDGE)
						{
							gateMayCloseAtHex = path.first[i-1];
						}
					}
					else if (hex == ESiegeHex::GATE_OUTER && i-1 >= 0 && path.first[i-1] != ESiegeHex::GATE_INNER)
					{
						gateMayCloseAtHex = path.first[i-1];
					}
				}
			}
		}

		bool stackIsMoving = true;

		while(stackIsMoving)
		{
			if (v<tilesToMove)
			{
				logGlobal->error("Movement terminated abnormally");
				break;
			}

			bool gateStateChanging = false;
			//special handling for opening gate on from starting hex
			if (openGateAtHex.isValid() && openGateAtHex == start)
				gateStateChanging = true;
			else
			{
				for (bool obstacleHit = false; (!obstacleHit) && (!gateStateChanging) && (v >= tilesToMove); --v)
				{
					BattleHex hex = path.first[v];
					tiles.push_back(hex);

					if ((openGateAtHex.isValid() && openGateAtHex == hex) ||
						(gateMayCloseAtHex.isValid() && gateMayCloseAtHex == hex))
					{
						gateStateChanging = true;
					}

					//if we walked onto something, finalize this portion of stack movement check into obstacle
					if(!battleGetAllObstaclesOnPos(hex, false).empty())
						obstacleHit = true;

					if (curStack->doubleWide())
					{
						BattleHex otherHex = curStack->occupiedHex(hex);
						//two hex creature hit obstacle by backside
						auto obstacle2 = battleGetAllObstaclesOnPos(otherHex, false);
						if(otherHex.isValid() && !obstacle2.empty())
							obstacleHit = true;
					}
				}
			}

			if (tiles.size() > 0)
			{
				//commit movement
				BattleStackMoved sm;
				sm.stack = curStack->ID;
				sm.distance = path.second;
				sm.teleporting = false;
				sm.tilesToMove = tiles;
				sendAndApply(&sm);
				tiles.clear();
			}

			//we don't handle obstacle at the destination tile -> it's handled separately in the if at the end
			if (curStack->getPosition() != dest)
			{
				if(stackIsMoving && start != curStack->getPosition())
					stackIsMoving = handleDamageFromObstacle(curStack, stackIsMoving);
				if (gateStateChanging)
				{
					if (curStack->getPosition() == openGateAtHex)
					{
						openGateAtHex = BattleHex();
						//only open gate if stack is still alive
						if (curStack->alive())
						{
							BattleUpdateGateState db;
							db.state = EGateState::OPENED;
							sendAndApply(&db);
						}
					}
					else if (curStack->getPosition() == gateMayCloseAtHex)
					{
						gateMayCloseAtHex = BattleHex();
						updateGateState();
					}
				}
			}
			else
				//movement finished normally: we reached destination
				stackIsMoving = false;
		}
	}

	//handling obstacle on the final field (separate, because it affects both flying and walking stacks)
	handleDamageFromObstacle(curStack);

	return ret;
}

CGameHandler::CGameHandler(CVCMIServer * lobby)
	: lobby(lobby)
{
	QID = 1;
	IObjectInterface::cb = this;
	applier = std::make_shared<CApplier<CBaseForGHApply>>();
	registerTypesServerPacks(*applier);
	visitObjectAfterVictory = false;

	spellEnv = new ServerSpellCastEnvironment(this);
}

CGameHandler::~CGameHandler()
{
	delete spellEnv;
	delete gs;
}

void CGameHandler::init(StartInfo *si)
{
	if (si->seedToBeUsed == 0)
	{
		si->seedToBeUsed = std::time(nullptr);
	}
	CMapService mapService;
	gs = new CGameState();
	logGlobal->info("Gamestate created!");
	gs->init(&mapService, si);
	logGlobal->info("Gamestate initialized!");

	// reset seed, so that clients can't predict any following random values
	getRandomGenerator().resetSeed();

	for (auto & elem : gs->players)
	{
		states.addPlayer(elem.first);
	}
}

static bool evntCmp(const CMapEvent &a, const CMapEvent &b)
{
	return a.earlierThan(b);
}

void CGameHandler::setPortalDwelling(const CGTownInstance * town, bool forced=false, bool clear = false)
{// bool forced = true - if creature should be replaced, if false - only if no creature was set
	const PlayerState * p = getPlayer(town->tempOwner);
	if (!p)
	{
		logGlobal->warn("There is no player owner of town %s at %s", town->name, town->pos.toString());
		return;
	}

	if (forced || town->creatures.at(GameConstants::CREATURES_PER_TOWN).second.empty())//we need to change creature
		{
			SetAvailableCreatures ssi;
			ssi.tid = town->id;
			ssi.creatures = town->creatures;
			ssi.creatures[GameConstants::CREATURES_PER_TOWN].second.clear();//remove old one

			const std::vector<ConstTransitivePtr<CGDwelling> > &dwellings = p->dwellings;
			if (dwellings.empty())//no dwellings - just remove
			{
				sendAndApply(&ssi);
				return;
			}

			auto dwelling = *RandomGeneratorUtil::nextItem(dwellings, getRandomGenerator());

			// for multi-creature dwellings like Golem Factory
			auto creatureId = RandomGeneratorUtil::nextItem(dwelling->creatures, getRandomGenerator())->second[0];

			if (clear)
			{
				ssi.creatures[GameConstants::CREATURES_PER_TOWN].first = std::max((ui32)1, (VLC->creh->creatures.at(creatureId)->growth)/2);
			}
			else
			{
				ssi.creatures[GameConstants::CREATURES_PER_TOWN].first = VLC->creh->creatures.at(creatureId)->growth;
			}
			ssi.creatures[GameConstants::CREATURES_PER_TOWN].second.push_back(creatureId);
			sendAndApply(&ssi);
		}
}

void CGameHandler::newTurn()
{
	logGlobal->trace("Turn %d", gs->day+1);
	NewTurn n;
	n.specialWeek = NewTurn::NO_ACTION;
	n.creatureid = CreatureID::NONE;
	n.day = gs->day + 1;

	bool firstTurn = !getDate(Date::DAY);
	bool newWeek = getDate(Date::DAY_OF_WEEK) == 7; //day numbers are confusing, as day was not yet switched
	bool newMonth = getDate(Date::DAY_OF_MONTH) == 28;

	std::map<PlayerColor, si32> hadGold;//starting gold - for buildings like dwarven treasury

	if (firstTurn)
	{
		for (auto obj : gs->map->objects)
		{
			if (obj && obj->ID == Obj::PRISON) //give imprisoned hero 0 exp to level him up. easiest to do at this point
			{
				changePrimSkill (getHero(obj->id), PrimarySkill::EXPERIENCE, 0);
			}
		}
	}

	if (newWeek && !firstTurn)
	{
		n.specialWeek = NewTurn::NORMAL;
		bool deityOfFireBuilt = false;
		for (const CGTownInstance *t : gs->map->towns)
		{
			if (t->hasBuilt(BuildingID::GRAIL, ETownType::INFERNO))
			{
				deityOfFireBuilt = true;
				break;
			}
		}

		if (deityOfFireBuilt)
		{
			n.specialWeek = NewTurn::DEITYOFFIRE;
			n.creatureid = CreatureID::IMP;
		}
		else if(!VLC->modh->settings.NO_RANDOM_SPECIAL_WEEKS_AND_MONTHS)
		{
			int monthType = getRandomGenerator().nextInt(99);
			if (newMonth) //new month
			{
				if (monthType < 40) //double growth
				{
					n.specialWeek = NewTurn::DOUBLE_GROWTH;
					if (VLC->modh->settings.ALL_CREATURES_GET_DOUBLE_MONTHS)
					{
						std::pair<int, CreatureID> newMonster(54, VLC->creh->pickRandomMonster(getRandomGenerator()));
						n.creatureid = newMonster.second;
					}
					else if (VLC->creh->doubledCreatures.size())
					{
						const std::vector<CreatureID> doubledCreatures (VLC->creh->doubledCreatures.begin(), VLC->creh->doubledCreatures.end());
						n.creatureid = *RandomGeneratorUtil::nextItem(doubledCreatures, getRandomGenerator());
					}
					else
					{
						complain("Cannot find creature that can be spawned!");
						n.specialWeek = NewTurn::NORMAL;
					}
				}
				else if (monthType < 50)
					n.specialWeek = NewTurn::PLAGUE;
			}
			else //it's a week, but not full month
			{
				if (monthType < 25)
				{
					n.specialWeek = NewTurn::BONUS_GROWTH; //+5
					std::pair<int, CreatureID> newMonster(54, VLC->creh->pickRandomMonster(getRandomGenerator()));
					//TODO do not pick neutrals
					n.creatureid = newMonster.second;
				}
			}
		}
	}

	std::map<ui32, ConstTransitivePtr<CGHeroInstance> > pool = gs->hpool.heroesPool;

	for (auto& hp : pool)
	{
		auto hero = hp.second;
		if (hero->isInitialized() && hero->stacks.size())
		{
			// reset retreated or surrendered heroes
			auto maxmove = hero->maxMovePoints(true);
			// if movement is greater than maxmove, we should decrease it
			if (hero->movement != maxmove || hero->mana < hero->manaLimit())
			{
				NewTurn::Hero hth;
				hth.id = hero->id;
				hth.move = maxmove;
				hth.mana = hero->getManaNewTurn();
				n.heroes.insert(hth);
			}
		}
	}

	for (auto & elem : gs->players)
	{
		if (elem.first == PlayerColor::NEUTRAL)
			continue;
		else if (elem.first >= PlayerColor::PLAYER_LIMIT)
			assert(0); //illegal player number!

		std::pair<PlayerColor, si32> playerGold(elem.first, elem.second.resources.at(Res::GOLD));
		hadGold.insert(playerGold);

		if (newWeek) //new heroes in tavern
		{
			SetAvailableHeroes sah;
			sah.player = elem.first;

			//pick heroes and their armies
			CHeroClass *banned = nullptr;
			for (int j = 0; j < GameConstants::AVAILABLE_HEROES_PER_PLAYER; j++)
			{
				//first hero - native if possible, second hero -> any other class
				if (CGHeroInstance *h = gs->hpool.pickHeroFor(j == 0, elem.first, getNativeTown(elem.first), pool, getRandomGenerator(), banned))
				{
					sah.hid[j] = h->subID;
					h->initArmy(getRandomGenerator(), &sah.army[j]);
					banned = h->type->heroClass;
				}
				else
				{
					sah.hid[j] = -1;
				}
			}

			sendAndApply(&sah);
		}

		n.res[elem.first] = elem.second.resources;

		if(!firstTurn && newWeek) //weekly crystal generation if 1 or more crystal dragons in any hero army or town garrison
		{
			bool hasCrystalGenCreature = false;
			for(CGHeroInstance * hero : elem.second.heroes)
			{
				for(auto stack : hero->stacks)
				{
					if(stack.second->hasBonusOfType(Bonus::SPECIAL_CRYSTAL_GENERATION))
					{
						hasCrystalGenCreature = true;
						break;
					}
				}
			}
			if(!hasCrystalGenCreature) //not found in armies, check towns
			{
				for(CGTownInstance * town : elem.second.towns)
				{
					for(auto stack : town->stacks)
					{
						if(stack.second->hasBonusOfType(Bonus::SPECIAL_CRYSTAL_GENERATION))
						{
							hasCrystalGenCreature = true;
							break;
						}
					}
				}
			}
			if(hasCrystalGenCreature)
				n.res[elem.first][Res::CRYSTAL] += 3;
		}

		for (CGHeroInstance *h : (elem).second.heroes)
		{
			if (h->visitedTown)
				giveSpells(h->visitedTown, h);

			NewTurn::Hero hth;
			hth.id = h->id;
			auto ti = make_unique<TurnInfo>(h, 1);
			// TODO: this code executed when bonuses of previous day not yet updated (this happen in NewTurn::applyGs). See issue 2356
			hth.move = h->maxMovePointsCached(gs->map->getTile(h->getPosition(false)).terType != ETerrainType::WATER, ti.get());
			hth.mana = h->getManaNewTurn();

			n.heroes.insert(hth);

			if (!firstTurn) //not first day
			{
				n.res[elem.first][Res::GOLD] += h->valOfBonuses(Selector::typeSubtype(Bonus::SECONDARY_SKILL_PREMY, SecondarySkill::ESTATES)); //estates

				for (int k = 0; k < GameConstants::RESOURCE_QUANTITY; k++)
				{
					n.res[elem.first][k] += h->valOfBonuses(Bonus::GENERATE_RESOURCE, k);
				}
			}
		}
	}
	for (CGTownInstance *t : gs->map->towns)
	{
		PlayerColor player = t->tempOwner;
		handleTownEvents(t, n);
		if (newWeek) //first day of week
		{
			if (t->hasBuilt(BuildingID::PORTAL_OF_SUMMON, ETownType::DUNGEON))
				setPortalDwelling(t, true, (n.specialWeek == NewTurn::PLAGUE ? true : false)); //set creatures for Portal of Summoning

			if (!firstTurn)
				if (t->hasBuilt(BuildingID::TREASURY, ETownType::RAMPART) && player < PlayerColor::PLAYER_LIMIT)
						n.res[player][Res::GOLD] += hadGold.at(player)/10; //give 10% of starting gold

			if (!vstd::contains(n.cres, t->id))
			{
				n.cres[t->id].tid = t->id;
				n.cres[t->id].creatures = t->creatures;
			}
			auto & sac = n.cres.at(t->id);

			for (int k=0; k < GameConstants::CREATURES_PER_TOWN; k++) //creature growths
			{
				if (!t->creatures.at(k).second.empty()) // there are creatures at this level
				{
					ui32 &availableCount = sac.creatures.at(k).first;
					const CCreature *cre = VLC->creh->creatures.at(t->creatures.at(k).second.back());

					if (n.specialWeek == NewTurn::PLAGUE)
						availableCount = t->creatures.at(k).first / 2; //halve their number, no growth
					else
					{
						if (firstTurn) //first day of game: use only basic growths
							availableCount = cre->growth;
						else
							availableCount += t->creatureGrowth(k);

						//Deity of fire week - upgrade both imps and upgrades
						if (n.specialWeek == NewTurn::DEITYOFFIRE && vstd::contains(t->creatures.at(k).second, n.creatureid))
							availableCount += 15;

						if (cre->idNumber == n.creatureid) //bonus week, effect applies only to identical creatures
						{
							if (n.specialWeek == NewTurn::DOUBLE_GROWTH)
								availableCount *= 2;
							else if (n.specialWeek == NewTurn::BONUS_GROWTH)
								availableCount += 5;
						}
					}
				}
			}
		}
		if (!firstTurn  &&  player < PlayerColor::PLAYER_LIMIT)//not the first day and town not neutral
		{
			n.res[player] = n.res[player] + t->dailyIncome();
		}
		if (t->hasBuilt(BuildingID::GRAIL, ETownType::TOWER))
		{
			// Skyship, probably easier to handle same as Veil of darkness
			//do it every new day after veils apply
			if (player != PlayerColor::NEUTRAL) //do not reveal fow for neutral player
			{
				FoWChange fw;
				fw.mode = 1;
				fw.player = player;
				// find all hidden tiles
				const auto & fow = getPlayerTeam(player)->fogOfWarMap;
				for (size_t i=0; i<fow.size(); i++)
					for (size_t j=0; j<fow.at(i).size(); j++)
						for (size_t k=0; k<fow.at(i).at(j).size(); k++)
							if (!fow.at(i).at(j).at(k))
								fw.tiles.insert(int3(i,j,k));

				sendAndApply (&fw);
			}
		}
		if (t->hasBonusOfType (Bonus::DARKNESS))
		{
			for (auto & player : gs->players)
			{
				if (getPlayerStatus(player.first) == EPlayerStatus::INGAME &&
					getPlayerRelations(player.first, t->tempOwner) == PlayerRelations::ENEMIES)
					changeFogOfWar(t->visitablePos(), t->getBonusLocalFirst(Selector::type(Bonus::DARKNESS))->val, player.first, true);
			}
		}
	}

	if (newMonth)
	{
		SetAvailableArtifacts saa;
		saa.id = -1;
		pickAllowedArtsSet(saa.arts, getRandomGenerator());
		sendAndApply(&saa);
	}
	sendAndApply(&n);

	if (newWeek)
	{
		//spawn wandering monsters
		if (newMonth && (n.specialWeek == NewTurn::DOUBLE_GROWTH || n.specialWeek == NewTurn::DEITYOFFIRE))
		{
			spawnWanderingMonsters(n.creatureid);
		}

		//new week info popup
		if (!firstTurn)
		{
			InfoWindow iw;
			switch (n.specialWeek)
			{
				case NewTurn::DOUBLE_GROWTH:
					iw.text.addTxt(MetaString::ARRAY_TXT, 131);
					iw.text.addReplacement(MetaString::CRE_SING_NAMES, n.creatureid);
					iw.text.addReplacement(MetaString::CRE_SING_NAMES, n.creatureid);
					break;
				case NewTurn::PLAGUE:
					iw.text.addTxt(MetaString::ARRAY_TXT, 132);
					break;
				case NewTurn::BONUS_GROWTH:
					iw.text.addTxt(MetaString::ARRAY_TXT, 134);
					iw.text.addReplacement(MetaString::CRE_SING_NAMES, n.creatureid);
					iw.text.addReplacement(MetaString::CRE_SING_NAMES, n.creatureid);
					break;
				case NewTurn::DEITYOFFIRE:
					iw.text.addTxt(MetaString::ARRAY_TXT, 135);
					iw.text.addReplacement(MetaString::CRE_SING_NAMES, 42); //%s imp
					iw.text.addReplacement(MetaString::CRE_SING_NAMES, 42); //%s imp
					iw.text.addReplacement2(15);							//%+d 15
					iw.text.addReplacement(MetaString::CRE_SING_NAMES, 43); //%s familiar
					iw.text.addReplacement2(15);							//%+d 15
					break;
				default:
					if (newMonth)
					{
						iw.text.addTxt(MetaString::ARRAY_TXT, (130));
						iw.text.addReplacement(MetaString::ARRAY_TXT, getRandomGenerator().nextInt(32, 41));
					}
					else
					{
						iw.text.addTxt(MetaString::ARRAY_TXT, (133));
						iw.text.addReplacement(MetaString::ARRAY_TXT, getRandomGenerator().nextInt(43, 57));
					}
			}
			for (auto & elem : gs->players)
			{
				iw.player = elem.first;
				sendAndApply(&iw);
			}
		}
	}

	logGlobal->trace("Info about turn %d has been sent!", n.day);
	handleTimeEvents();
	//call objects
	for (auto & elem : gs->map->objects)
	{
		if (elem)
			elem->newTurn(getRandomGenerator());
	}

	synchronizeArtifactHandlerLists(); //new day events may have changed them. TODO better of managing that
}
void CGameHandler::run(bool resume)
{
	LOG_TRACE_PARAMS(logGlobal, "resume=%d", resume);

	using namespace boost::posix_time;
	for (auto cc : lobby->connections)
	{
		auto players = lobby->getAllClientPlayers(cc->connectionID);
		std::stringstream sbuffer;
		sbuffer << "Connection " << cc->connectionID << " will handle " << players.size() << " player: ";
		for (PlayerColor color : players)
		{
			sbuffer << color << " ";
			{
				boost::unique_lock<boost::recursive_mutex> lock(gsm);
				connections[color].insert(cc);
			}
		}
		logGlobal->info(sbuffer.str());
	}

	auto playerTurnOrder = generatePlayerTurnOrder();

	while(lobby->state == EServerState::GAMEPLAY)
	{
		if (!resume) newTurn();

		std::list<PlayerColor>::iterator it;
		if (resume)
		{
			it = std::find(playerTurnOrder.begin(), playerTurnOrder.end(), gs->currentPlayer);
		}
		else
		{
			it = playerTurnOrder.begin();
		}

		resume = false;
		for (; it != playerTurnOrder.end(); it++)
		{
			auto playerColor = *it;

			PlayerState * playerState = &gs->players[playerColor]; //can't copy CBonusSystemNode by value
			if (playerState->status == EPlayerStatus::INGAME)
			{
				//if player runs out of time, he shouldn't get the turn (especially AI)
				checkVictoryLossConditionsForAll();

				if (gs->players[playerColor].status != EPlayerStatus::INGAME)
				{ //player lost at the beginning of his turn
					continue;
				}
				else //give normal turn
				{
					states.setFlag(playerColor, &PlayerStatus::makingTurn, true);

					YourTurn yt;
					yt.player = playerColor;
					//Change local daysWithoutCastle counter for local interface message //TODO: needed?
					yt.daysWithoutCastle = playerState->daysWithoutCastle;
					applyAndSend(&yt);

					//wait till turn is done
					boost::unique_lock<boost::mutex> lock(states.mx);
					while(states.players.at(playerColor).makingTurn && lobby->state == EServerState::GAMEPLAY)
					{
						static time_duration p = milliseconds(100);
						states.cv.timed_wait(lock, p);
					}
				}
				if(lobby->state != EServerState::GAMEPLAY)
					break;
			}
		}
		//additional check that game is not finished
		bool activePlayer = false;
		for (auto player : playerTurnOrder)
		{
			if (gs->players[player].status == EPlayerStatus::INGAME)
					activePlayer = true;
		}
		if(!activePlayer)
			lobby->state = EServerState::GAMEPLAY_ENDED;
	}
}

std::list<PlayerColor> CGameHandler::generatePlayerTurnOrder() const
{
	// Generate player turn order
	std::list<PlayerColor> playerTurnOrder;

	for (const auto & player : gs->players) // add human players first
	{
		if (player.second.human)
			playerTurnOrder.push_back(player.first);
	}
	for (const auto & player : gs->players) // then add non-human players
	{
		if (!player.second.human)
			playerTurnOrder.push_back(player.first);
	}
	return playerTurnOrder;
}

void CGameHandler::setupBattle(int3 tile, const CArmedInstance *armies[2], const CGHeroInstance *heroes[2], bool creatureBank, const CGTownInstance *town)
{
	battleResult.set(nullptr);

	const auto t = getTile(tile);
	ETerrainType terrain = t->terType;
	if (gs->map->isCoastalTile(tile)) //coastal tile is always ground
		terrain = ETerrainType::SAND;

	BFieldType terType = gs->battleGetBattlefieldType(tile, getRandomGenerator());
	if (heroes[0] && heroes[0]->boat && heroes[1] && heroes[1]->boat)
		terType = BFieldType::SHIP_TO_SHIP;

	//send info about battles
	BattleStart bs;
	bs.info = BattleInfo::setupBattle(tile, terrain, terType, armies, heroes, creatureBank, town);
	sendAndApply(&bs);
}

void CGameHandler::checkBattleStateChanges()
{
	//check if drawbridge state need to be changes
	if (battleGetSiegeLevel() > 0)
		updateGateState();

	//check if battle ended
	if (auto result = battleIsFinished())
	{
		setBattleResult(BattleResult::NORMAL, *result);
	}
}

void CGameHandler::giveSpells(const CGTownInstance *t, const CGHeroInstance *h)
{
	if (!h->hasSpellbook())
		return; //hero hasn't spellbook
	ChangeSpells cs;
	cs.hid = h->id;
	cs.learn = true;
	if (t->hasBuilt(BuildingID::GRAIL, ETownType::CONFLUX) && t->hasBuilt(BuildingID::MAGES_GUILD_1))
	{
		// Aurora Borealis give spells of all levels even if only level 1 mages guild built
		for (int i = 0; i < h->maxSpellLevel(); i++)
		{
			std::vector<SpellID> spells;
			getAllowedSpells(spells, i+1);
			for (auto & spell : spells)
				cs.spells.insert(spell);
		}
	}
	else
	{
		for (int i = 0; i < std::min(t->mageGuildLevel(), h->maxSpellLevel()); i++)
		{
			for (int j = 0; j < t->spellsAtLevel(i+1, true) && j < t->spells.at(i).size(); j++)
			{
				if (!h->spellbookContainsSpell(t->spells.at(i).at(j)))
					cs.spells.insert(t->spells.at(i).at(j));
			}
		}
	}
	if (!cs.spells.empty())
		sendAndApply(&cs);
}

void CGameHandler::setBlockVis(ObjectInstanceID objid, bool bv)
{
	SetObjectProperty sop(objid, ObjProperty::BLOCKVIS, bv);
	sendAndApply(&sop);
}

bool CGameHandler::removeObject(const CGObjectInstance * obj)
{
	if (!obj || !getObj(obj->id))
	{
		logGlobal->error("Something wrong, that object already has been removed or hasn't existed!");
		return false;
	}

	RemoveObject ro;
	ro.id = obj->id;
	sendAndApply(&ro);

	checkVictoryLossConditionsForAll(); //eg if monster escaped (removing objs after battle is done dircetly by endBattle, not this function)
	return true;
}

void CGameHandler::setAmount(ObjectInstanceID objid, ui32 val)
{
	SetObjectProperty sop(objid, ObjProperty::PRIMARY_STACK_COUNT, val);
	sendAndApply(&sop);
}

bool CGameHandler::moveHero(ObjectInstanceID hid, int3 dst, ui8 teleporting, bool transit, PlayerColor asker)
{
	const CGHeroInstance *h = getHero(hid);
	// not turn of that hero or player can't simply teleport hero (at least not with this function)
	if (!h  || (asker != PlayerColor::NEUTRAL && (teleporting || h->getOwner() != gs->currentPlayer)))
	{
		logGlobal->error("Illegal call to move hero!");
		return false;
	}

	logGlobal->trace("Player %d (%s) wants to move hero %d from %s to %s", asker, asker.getStr(), hid.getNum(), h->pos.toString(), dst.toString());
	const int3 hmpos = CGHeroInstance::convertPosition(dst, false);

	if (!gs->map->isInTheMap(hmpos))
	{
		logGlobal->error("Destination tile is outside the map!");
		return false;
	}

	const TerrainTile t = *getTile(hmpos);
	const int3 guardPos = gs->guardingCreaturePosition(hmpos);

	const bool embarking = !h->boat && !t.visitableObjects.empty() && t.visitableObjects.back()->ID == Obj::BOAT;
	const bool disembarking = h->boat && t.terType != ETerrainType::WATER && !t.blocked;

	//result structure for start - movement failed, no move points used
	TryMoveHero tmh;
	tmh.id = hid;
	tmh.start = h->pos;
	tmh.end = dst;
	tmh.result = TryMoveHero::FAILED;
	tmh.movePoints = h->movement;

	//check if destination tile is available
	auto pathfinderHelper = make_unique<CPathfinderHelper>(gs, h, PathfinderOptions());

	pathfinderHelper->updateTurnInfo(0);
	auto ti = pathfinderHelper->getTurnInfo();

	const bool canFly = pathfinderHelper->hasBonusOfType(Bonus::FLYING_MOVEMENT);
	const bool canWalkOnSea = pathfinderHelper->hasBonusOfType(Bonus::WATER_WALKING);
	const int cost = pathfinderHelper->getMovementCost(h->getPosition(), hmpos, nullptr, nullptr, h->movement);

	//it's a rock or blocked and not visitable tile
	//OR hero is on land and dest is water and (there is not present only one object - boat)
	if (((t.terType == ETerrainType::ROCK  ||  (t.blocked && !t.visitable && !canFly))
			&& complain("Cannot move hero, destination tile is blocked!"))
		|| ((!h->boat && !canWalkOnSea && !canFly && t.terType == ETerrainType::WATER && (t.visitableObjects.size() < 1 ||  (t.visitableObjects.back()->ID != Obj::BOAT && t.visitableObjects.back()->ID != Obj::HERO)))  //hero is not on boat/water walking and dst water tile doesn't contain boat/hero (objs visitable from land) -> we test back cause boat may be on top of another object (#276)
			&& complain("Cannot move hero, destination tile is on water!"))
		|| ((h->boat && t.terType != ETerrainType::WATER && t.blocked)
			&& complain("Cannot disembark hero, tile is blocked!"))
		|| ((distance(h->pos, dst) >= 1.5 && !teleporting)
			&& complain("Tiles are not neighboring!"))
		|| ((h->inTownGarrison)
			&& complain("Can not move garrisoned hero!"))
		|| ((h->movement < cost  &&  dst != h->pos  &&  !teleporting)
			&& complain("Hero doesn't have any movement points left!"))
		|| ((transit && !canFly && !CGTeleport::isTeleport(t.topVisitableObj()))
			&& complain("Hero cannot transit over this tile!"))
		/*|| (states.checkFlag(h->tempOwner, &PlayerStatus::engagedIntoBattle)
			&& complain("Cannot move hero during the battle"))*/)
	{
		//send info about movement failure
		sendAndApply(&tmh);
		return false;
	}

	//several generic blocks of code

	// should be called if hero changes tile but before applying TryMoveHero package
	auto leaveTile = [&]()
	{
		for (CGObjectInstance *obj : gs->map->getTile(int3(h->pos.x-1, h->pos.y, h->pos.z)).visitableObjects)
		{
			obj->onHeroLeave(h);
		}
		this->getTilesInRange(tmh.fowRevealed, h->getSightCenter()+(tmh.end-tmh.start), h->getSightRadius(), h->tempOwner, 1);
	};

	auto doMove = [&](TryMoveHero::EResult result, EGuardLook lookForGuards,
								EVisitDest visitDest, ELEaveTile leavingTile) -> bool
	{
		LOG_TRACE_PARAMS(logGlobal, "Hero %s starts movement from %s to %s", h->name % tmh.start.toString() % tmh.end.toString());

		auto moveQuery = std::make_shared<CHeroMovementQuery>(this, tmh, h);
		queries.addQuery(moveQuery);

		if (leavingTile == LEAVING_TILE)
			leaveTile();

		tmh.result = result;
		sendAndApply(&tmh);

		if (visitDest == VISIT_DEST && t.topVisitableObj() && t.topVisitableObj()->id == h->id)
		{ // Hero should be always able to visit any object he staying on even if there guards around
			visitObjectOnTile(t, h);
		}
		else if (lookForGuards == CHECK_FOR_GUARDS && this->isInTheMap(guardPos))
		{
			tmh.attackedFrom = boost::make_optional(guardPos);

			const TerrainTile &guardTile = *gs->getTile(guardPos);
			objectVisited(guardTile.visitableObjects.back(), h);

			moveQuery->visitDestAfterVictory = visitDest==VISIT_DEST;
		}
		else if (visitDest == VISIT_DEST)
		{
			visitObjectOnTile(t, h);
		}

		queries.popIfTop(moveQuery);
		logGlobal->trace("Hero %s ends movement", h->name);
		return result != TryMoveHero::FAILED;
	};

	//interaction with blocking object (like resources)
	auto blockingVisit = [&]() -> bool
	{
		for (CGObjectInstance *obj : t.visitableObjects)
		{
			if (obj != h  &&  obj->blockVisit  &&  !obj->passableFor(h->tempOwner))
			{
				return doMove(TryMoveHero::BLOCKING_VISIT, this->IGNORE_GUARDS, VISIT_DEST, REMAINING_ON_TILE);
				//this-> is needed for MVS2010 to recognize scope (?)
			}
		}
		return false;
	};


	if (!transit && embarking)
	{
		tmh.movePoints = h->movementPointsAfterEmbark(h->movement, cost, false, ti);
		return doMove(TryMoveHero::EMBARK, IGNORE_GUARDS, DONT_VISIT_DEST, LEAVING_TILE);
		// In H3 embark ignore guards
	}

	if (disembarking)
	{
		tmh.movePoints = h->movementPointsAfterEmbark(h->movement, cost, true, ti);
		return doMove(TryMoveHero::DISEMBARK, CHECK_FOR_GUARDS, VISIT_DEST, LEAVING_TILE);
	}

	if (teleporting)
	{
		if (blockingVisit()) // e.g. hero on the other side of teleporter
			return true;

		doMove(TryMoveHero::TELEPORTATION, IGNORE_GUARDS, DONT_VISIT_DEST, LEAVING_TILE);

		// visit town for town portal \ castle gates
		// do not use generic visitObjectOnTile to avoid double-teleporting
		// if this moveHero call was triggered by teleporter
		if (!t.visitableObjects.empty())
		{
			if (CGTownInstance * town = dynamic_cast<CGTownInstance *>(t.visitableObjects.back()))
				town->onHeroVisit(h);
		}

		return true;
	}

	//still here? it is standard movement!
	{
		tmh.movePoints = h->movement >= cost
						? h->movement - cost
						: 0;

		EGuardLook lookForGuards = CHECK_FOR_GUARDS;
		EVisitDest visitDest = VISIT_DEST;
		if (transit)
		{
			if (CGTeleport::isTeleport(t.topVisitableObj()))
				visitDest = DONT_VISIT_DEST;

			if (canFly)
			{
				lookForGuards = IGNORE_GUARDS;
				visitDest = DONT_VISIT_DEST;
			}
		}
		else if (blockingVisit())
			return true;

		doMove(TryMoveHero::SUCCESS, lookForGuards, visitDest, LEAVING_TILE);
		return true;
	}
}

bool CGameHandler::teleportHero(ObjectInstanceID hid, ObjectInstanceID dstid, ui8 source, PlayerColor asker)
{
	const CGHeroInstance *h = getHero(hid);
	const CGTownInstance *t = getTown(dstid);

	if (!h || !t || h->getOwner() != gs->currentPlayer)
		COMPLAIN_RET("Invalid call to teleportHero!");

	const CGTownInstance *from = h->visitedTown;
	if (((h->getOwner() != t->getOwner())
		&& complain("Cannot teleport hero to another player"))
	|| ((!from || !from->hasBuilt(BuildingID::CASTLE_GATE, ETownType::INFERNO))
		&& complain("Hero must be in town with Castle gate for teleporting"))
	|| (!t->hasBuilt(BuildingID::CASTLE_GATE, ETownType::INFERNO)
		&& complain("Cannot teleport hero to town without Castle gate in it")))
			return false;
	int3 pos = t->visitablePos();
	pos += h->getVisitableOffset();
	moveHero(hid,pos,1);
	return true;
}

void CGameHandler::setOwner(const CGObjectInstance * obj, PlayerColor owner)
{
	PlayerColor oldOwner = getOwner(obj->id);
	SetObjectProperty sop(obj->id, ObjProperty::OWNER, owner.getNum());
	sendAndApply(&sop);

	std::set<PlayerColor> playerColors = {owner, oldOwner};
	checkVictoryLossConditions(playerColors);

	const CGTownInstance * town = dynamic_cast<const CGTownInstance *>(obj);
	if (town) //town captured
	{
		if (owner < PlayerColor::PLAYER_LIMIT) //new owner is real player
		{
			if (town->hasBuilt(BuildingID::PORTAL_OF_SUMMON, ETownType::DUNGEON))
				setPortalDwelling(town, true, false);
		}

		if (oldOwner < PlayerColor::PLAYER_LIMIT) //old owner is real player
		{
			if (getPlayer(oldOwner)->towns.empty()) //previous player lost last last town
			{
				InfoWindow iw;
				iw.player = oldOwner;
				iw.text.addTxt(MetaString::GENERAL_TXT, 6); //%s, you have lost your last town. If you do not conquer another town in the next week, you will be eliminated.
				iw.text.addReplacement(MetaString::COLOR, oldOwner.getNum());
				sendAndApply(&iw);
			}
		}
	}

	const PlayerState * p = getPlayer(owner);

	if ((obj->ID == Obj::CREATURE_GENERATOR1 || obj->ID == Obj::CREATURE_GENERATOR4) && p && p->dwellings.size()==1)//first dwelling captured
	{
		for (const CGTownInstance * t : getPlayer(owner)->towns)
		{
			if (t->hasBuilt(BuildingID::PORTAL_OF_SUMMON, ETownType::DUNGEON))
				setPortalDwelling(t);//set initial creatures for all portals of summoning
		}
	}
}

void CGameHandler::showBlockingDialog(BlockingDialog *iw)
{
	auto dialogQuery = std::make_shared<CBlockingDialogQuery>(this, *iw);
	queries.addQuery(dialogQuery);
	iw->queryID = dialogQuery->queryID;
	sendToAllClients(iw);
}

void CGameHandler::showTeleportDialog(TeleportDialog *iw)
{
	auto dialogQuery = std::make_shared<CTeleportDialogQuery>(this, *iw);
	queries.addQuery(dialogQuery);
	iw->queryID = dialogQuery->queryID;
	sendToAllClients(iw);
}

void CGameHandler::giveResource(PlayerColor player, Res::ERes which, int val) //TODO: cap according to Bersy's suggestion
{
	if (!val) return; //don't waste time on empty call

	TResources resources;
	resources.at(which) = val;
	giveResources(player, resources);
}

void CGameHandler::giveResources(PlayerColor player, TResources resources)
{
	SetResources sr;
	sr.abs = false;
	sr.player = player;
	sr.res = resources;
	sendAndApply(&sr);
}

void CGameHandler::giveCreatures(const CArmedInstance *obj, const CGHeroInstance * h, const CCreatureSet &creatures, bool remove)
{
	COMPLAIN_RET_IF(!creatures.stacksCount(), "Strange, giveCreatures called without args!");
	COMPLAIN_RET_IF(obj->stacksCount(), "Cannot give creatures from not-cleared object!");
	COMPLAIN_RET_IF(creatures.stacksCount() > GameConstants::ARMY_SIZE, "Too many stacks to give!");

	//first we move creatures to give to make them army of object-source
	for (auto & elem : creatures.Slots())
	{
		addToSlot(StackLocation(obj, obj->getSlotFor(elem.second->type)), elem.second->type, elem.second->count);
	}

	tryJoiningArmy(obj, h, remove, true);
}

void CGameHandler::takeCreatures(ObjectInstanceID objid, const std::vector<CStackBasicDescriptor> &creatures)
{
	std::vector<CStackBasicDescriptor> cres = creatures;
	if (cres.size() <= 0)
		return;
	const CArmedInstance* obj = static_cast<const CArmedInstance*>(getObj(objid));

	for (CStackBasicDescriptor &sbd : cres)
	{
		TQuantity collected = 0;
		while(collected < sbd.count)
		{
			bool foundSth = false;
			for (auto i = obj->Slots().begin(); i != obj->Slots().end(); i++)
			{
				if (i->second->type == sbd.type)
				{
					TQuantity take = std::min(sbd.count - collected, i->second->count); //collect as much cres as we can
					changeStackCount(StackLocation(obj, i->first), -take, false);
					collected += take;
					foundSth = true;
					break;
				}
			}

			if (!foundSth) //we went through the whole loop and haven't found appropriate cres
			{
				complain("Unexpected failure during taking creatures!");
				return;
			}
		}
	}
}

void CGameHandler::showCompInfo(ShowInInfobox * comp)
{
	sendToAllClients(comp);
}
void CGameHandler::heroVisitCastle(const CGTownInstance * obj, const CGHeroInstance * hero)
{
	HeroVisitCastle vc;
	vc.hid = hero->id;
	vc.tid = obj->id;
	vc.flags |= 1;
	sendAndApply(&vc);
	vistiCastleObjects (obj, hero);
	giveSpells (obj, hero);

	checkVictoryLossConditionsForPlayer(hero->tempOwner); //transported artifact?
}

void CGameHandler::vistiCastleObjects (const CGTownInstance *t, const CGHeroInstance *h)
{
	std::vector<CGTownBuilding*>::const_iterator i;
	for (i = t->bonusingBuildings.begin(); i != t->bonusingBuildings.end(); i++)
		(*i)->onHeroVisit (h);
}

void CGameHandler::stopHeroVisitCastle(const CGTownInstance * obj, const CGHeroInstance * hero)
{
	HeroVisitCastle vc;
	vc.hid = hero->id;
	vc.tid = obj->id;
	sendAndApply(&vc);
}

void CGameHandler::removeArtifact(const ArtifactLocation &al)
{
	EraseArtifact ea;
	ea.al = al;
	sendAndApply(&ea);
}
void CGameHandler::startBattlePrimary(const CArmedInstance *army1, const CArmedInstance *army2, int3 tile,
								const CGHeroInstance *hero1, const CGHeroInstance *hero2, bool creatureBank,
								const CGTownInstance *town) //use hero=nullptr for no hero
{
	engageIntoBattle(army1->tempOwner);
	engageIntoBattle(army2->tempOwner);

	static const CArmedInstance *armies[2];
	armies[0] = army1;
	armies[1] = army2;
	static const CGHeroInstance*heroes[2];
	heroes[0] = hero1;
	heroes[1] = hero2;


	setupBattle(tile, armies, heroes, creatureBank, town); //initializes stacks, places creatures on battlefield, blocks and informs player interfaces

	auto battleQuery = std::make_shared<CBattleQuery>(this, gs->curB);
	queries.addQuery(battleQuery);

	boost::thread(&CGameHandler::runBattle, this);
}

void CGameHandler::startBattleI(const CArmedInstance *army1, const CArmedInstance *army2, int3 tile, bool creatureBank)
{
	startBattlePrimary(army1, army2, tile,
		army1->ID == Obj::HERO ? static_cast<const CGHeroInstance*>(army1) : nullptr,
		army2->ID == Obj::HERO ? static_cast<const CGHeroInstance*>(army2) : nullptr,
		creatureBank);
}

void CGameHandler::startBattleI(const CArmedInstance *army1, const CArmedInstance *army2, bool creatureBank)
{
	startBattleI(army1, army2, army2->visitablePos(), creatureBank);
}

void CGameHandler::changeSpells(const CGHeroInstance * hero, bool give, const std::set<SpellID> &spells)
{
	ChangeSpells cs;
	cs.hid = hero->id;
	cs.spells = spells;
	cs.learn = give;
	sendAndApply(&cs);
}

void CGameHandler::sendMessageTo(std::shared_ptr<CConnection> c, const std::string &message)
{
	SystemMessage sm;
	sm.text = message;
	boost::unique_lock<boost::mutex> lock(*c->mutexWrite);
	*(c.get()) << &sm;
}

void CGameHandler::giveHeroBonus(GiveBonus * bonus)
{
	sendAndApply(bonus);
}

void CGameHandler::setMovePoints(SetMovePoints * smp)
{
	sendAndApply(smp);
}

void CGameHandler::setManaPoints(ObjectInstanceID hid, int val)
{
	SetMana sm;
	sm.hid = hid;
	sm.val = val;
	sm.absolute = true;
	sendAndApply(&sm);
}

void CGameHandler::giveHero(ObjectInstanceID id, PlayerColor player)
{
	GiveHero gh;
	gh.id = id;
	gh.player = player;
	sendAndApply(&gh);
}

void CGameHandler::changeObjPos(ObjectInstanceID objid, int3 newPos, ui8 flags)
{
	ChangeObjPos cop;
	cop.objid = objid;
	cop.nPos = newPos;
	cop.flags = flags;
	sendAndApply(&cop);
}

void CGameHandler::useScholarSkill(ObjectInstanceID fromHero, ObjectInstanceID toHero)
{
	const CGHeroInstance * h1 = getHero(fromHero);
	const CGHeroInstance * h2 = getHero(toHero);
	int h1_scholarLevel = h1->valOfBonuses(Bonus::SECONDARY_SKILL_PREMY, SecondarySkill::SCHOLAR);
	int h2_scholarLevel = h2->valOfBonuses(Bonus::SECONDARY_SKILL_PREMY, SecondarySkill::SCHOLAR);

	if (h1_scholarLevel < h2_scholarLevel)
	{
		std::swap (h1,h2);//1st hero need to have higher scholar level for correct message
		std::swap(fromHero, toHero);
	}

	int ScholarLevel = std::max(h1_scholarLevel, h2_scholarLevel);//heroes can trade up to this level
	if (!ScholarLevel || !h1->hasSpellbook() || !h2->hasSpellbook())
		return;//no scholar skill or no spellbook

	int h1Lvl = std::min(ScholarLevel, h1->maxSpellLevel()),
		h2Lvl = std::min(ScholarLevel, h2->maxSpellLevel());//heroes can receive this levels

	ChangeSpells cs1;
	cs1.learn = true;
	cs1.hid = toHero;//giving spells to first hero
	for (auto it : h1->getSpellsInSpellbook())
		if (h2Lvl >= it.toSpell()->level && !h2->spellbookContainsSpell(it))//hero can learn it and don't have it yet
			cs1.spells.insert(it);//spell to learn

	ChangeSpells cs2;
	cs2.learn = true;
	cs2.hid = fromHero;

	for (auto it : h2->getSpellsInSpellbook())
		if (h1Lvl >= it.toSpell()->level && !h1->spellbookContainsSpell(it))
			cs2.spells.insert(it);

	if (!cs1.spells.empty() || !cs2.spells.empty())//create a message
	{
		InfoWindow iw;
		iw.player = h1->tempOwner;
		iw.components.push_back(Component(Component::SEC_SKILL, 18, ScholarLevel, 0));

		iw.text.addTxt(MetaString::GENERAL_TXT, 139);//"%s, who has studied magic extensively,
		iw.text.addReplacement(h1->name);

		if (!cs2.spells.empty())//if found new spell - apply
		{
			iw.text.addTxt(MetaString::GENERAL_TXT, 140);//learns
			int size = cs2.spells.size();
			for (auto it : cs2.spells)
			{
				iw.components.push_back(Component(Component::SPELL, it, 1, 0));
				iw.text.addTxt(MetaString::SPELL_NAME, it.toEnum());
				switch (size--)
				{
					case 2:	iw.text.addTxt(MetaString::GENERAL_TXT, 141);
					case 1:	break;
					default:	iw.text << ", ";
				}
			}
			iw.text.addTxt(MetaString::GENERAL_TXT, 142);//from %s
			iw.text.addReplacement(h2->name);
			sendAndApply(&cs2);
		}

		if (!cs1.spells.empty() && !cs2.spells.empty())
		{
			iw.text.addTxt(MetaString::GENERAL_TXT, 141);//and
		}

		if (!cs1.spells.empty())
		{
			iw.text.addTxt(MetaString::GENERAL_TXT, 147);//teaches
			int size = cs1.spells.size();
			for (auto it : cs1.spells)
			{
				iw.components.push_back(Component(Component::SPELL, it, 1, 0));
				iw.text.addTxt(MetaString::SPELL_NAME, it.toEnum());
				switch (size--)
				{
					case 2:	iw.text.addTxt(MetaString::GENERAL_TXT, 141);
					case 1:	break;
					default:	iw.text << ", ";
				}			}
			iw.text.addTxt(MetaString::GENERAL_TXT, 148);//from %s
			iw.text.addReplacement(h2->name);
			sendAndApply(&cs1);
		}
		sendAndApply(&iw);
	}
}

void CGameHandler::heroExchange(ObjectInstanceID hero1, ObjectInstanceID hero2)
{
	auto h1 = getHero(hero1), h2 = getHero(hero2);

	if (getPlayerRelations(h1->getOwner(), h2->getOwner()))
	{
		auto exchange = std::make_shared<CGarrisonDialogQuery>(this, h1, h2);
		ExchangeDialog hex;
		hex.queryID = exchange->queryID;
		hex.player = h1->getOwner();
		hex.hero1 = hero1;
		hex.hero2 = hero2;
		sendAndApply(&hex);

		useScholarSkill(hero1,hero2);
		queries.addQuery(exchange);
	}
}

void CGameHandler::sendToAllClients(CPackForClient * pack)
{
	logNetwork->trace("\tSending to all clients: %s", typeid(*pack).name());
	for (auto c : lobby->connections)
	{
		if(!c->isOpen())
			continue;

		c->sendPack(pack);
	}
}

void CGameHandler::sendAndApply(CPackForClient * pack)
{
	sendToAllClients(pack);
	gs->apply(pack);
	logNetwork->trace("\tApplied on gs: %s", typeid(*pack).name());
}

void CGameHandler::applyAndSend(CPackForClient * pack)
{
	gs->apply(pack);
	sendToAllClients(pack);
}

void CGameHandler::sendAndApply(CGarrisonOperationPack * pack)
{
	sendAndApply(static_cast<CPackForClient *>(pack));
	checkVictoryLossConditionsForAll();
}

void CGameHandler::sendAndApply(SetResources * pack)
{
	sendAndApply(static_cast<CPackForClient *>(pack));
	checkVictoryLossConditionsForPlayer(pack->player);
}

void CGameHandler::sendAndApply(NewStructures * pack)
{
	sendAndApply(static_cast<CPackForClient *>(pack));
	checkVictoryLossConditionsForPlayer(getTown(pack->tid)->tempOwner);
}

void CGameHandler::save(const std::string & filename)
{
	logGlobal->info("Loading from %s", filename);
	const auto stem	= FileInfo::GetPathStem(filename);
	const auto savefname = stem.to_string() + ".vsgm1";
	CResourceHandler::get("local")->createResource(savefname);

	{
		logGlobal->info("Ordering clients to serialize...");
		SaveGameClient sg(savefname);
		sendToAllClients(&sg);
	}

	try
	{
		{
			CSaveFile save(*CResourceHandler::get("local")->getResourceName(ResourceID(stem.to_string(), EResType::SERVER_SAVEGAME)));
			saveCommonState(save);
			logGlobal->info("Saving server state");
			save << *this;
		}
		logGlobal->info("Game has been successfully saved!");
	}
	catch(std::exception &e)
	{
		logGlobal->error("Failed to save game: %s", e.what());
	}
}

void CGameHandler::load(const std::string & filename)
{
	logGlobal->info("Loading from %s", filename);
	const auto stem	= FileInfo::GetPathStem(filename);

	try
	{
		{
			CLoadFile lf(*CResourceHandler::get("local")->getResourceName(ResourceID(stem.to_string(), EResType::SERVER_SAVEGAME)), MINIMAL_SERIALIZATION_VERSION);
			loadCommonState(lf);
			logGlobal->info("Loading server state");
			lf >> *this;
		}
		logGlobal->info("Game has been successfully loaded!");
	}
	catch(std::exception &e)
	{
		logGlobal->error("Failed to load game: %s", e.what());
	}
	gs->updateOnLoad(lobby->si.get());
}

bool CGameHandler::arrangeStacks(ObjectInstanceID id1, ObjectInstanceID id2, ui8 what, SlotID p1, SlotID p2, si32 val, PlayerColor player)
{
	const CArmedInstance * s1 = static_cast<const CArmedInstance *>(getObjInstance(id1)),
		* s2 = static_cast<const CArmedInstance *>(getObjInstance(id2));
	const CCreatureSet &S1 = *s1, &S2 = *s2;
	StackLocation sl1(s1, p1), sl2(s2, p2);
	if (!sl1.slot.validSlot()  ||  !sl2.slot.validSlot())
	{
		complain("Invalid slot accessed!");
		return false;
	}

	if (!isAllowedExchange(id1,id2))
	{
		complain("Cannot exchange stacks between these two objects!\n");
		return false;
	}

	// We can always put stacks into locked garrison, but not take them out of it
	auto notRemovable = [&](const CArmedInstance * army)
	{
		if (id1 != id2) // Stack arrangement inside locked garrison is allowed
		{
			auto g = dynamic_cast<const CGGarrison *>(army);
			if (g && !g->removableUnits)
			{
				complain("Stacks in this garrison are not removable!\n");
				return true;
			}
		}
		return false;
	};

	if (what==1) //swap
	{
		if (((s1->tempOwner != player && s1->tempOwner != PlayerColor::UNFLAGGABLE) && s1->getStackCount(p1))
		  || ((s2->tempOwner != player && s2->tempOwner != PlayerColor::UNFLAGGABLE) && s2->getStackCount(p2)))
		{
			complain("Can't take troops from another player!");
			return false;
		}

		if (sl1.army == sl2.army && sl1.slot == sl2.slot)
		{
			complain("Cannot swap stacks - slots are the same!");
			return false;
		}

		if (!s1->slotEmpty(p1) && !s2->slotEmpty(p2))
		{
			if (notRemovable(sl1.army) || notRemovable(sl2.army))
				return false;
		}
		if (s1->slotEmpty(p1) && notRemovable(sl2.army))
			return false;
		else if (s2->slotEmpty(p2) && notRemovable(sl1.army))
			return false;

		swapStacks(sl1, sl2);
	}
	else if (what==2)//merge
	{
		if ((s1->getCreature(p1) != s2->getCreature(p2) && complain("Cannot merge different creatures stacks!"))
		|| (((s1->tempOwner != player && s1->tempOwner != PlayerColor::UNFLAGGABLE) && s2->getStackCount(p2)) && complain("Can't take troops from another player!")))
			return false;

		if (s1->slotEmpty(p1) || s2->slotEmpty(p2))
		{
			complain("Cannot merge empty stack!");
			return false;
		}
		else if (notRemovable(sl1.army))
			return false;

		moveStack(sl1, sl2);
	}
	else if (what==3) //split
	{
		const int countToMove = val - s2->getStackCount(p2);
		const int countLeftOnSrc = s1->getStackCount(p1) - countToMove;

		if (  (s1->tempOwner != player && countLeftOnSrc < s1->getStackCount(p1))
			|| (s2->tempOwner != player && val < s2->getStackCount(p2)))
		{
			complain("Can't move troops of another player!");
			return false;
		}

		//general conditions checking
		if ((!vstd::contains(S1.stacks,p1) && complain("no creatures to split"))
			|| (val<1  && complain("no creatures to split")) )
		{
			return false;
		}


		if (vstd::contains(S2.stacks,p2))	 //dest. slot not free - it must be "rebalancing"...
		{
			int total = s1->getStackCount(p1) + s2->getStackCount(p2);
			if ((total < val   &&   complain("Cannot split that stack, not enough creatures!"))
				|| (s1->getCreature(p1) != s2->getCreature(p2) && complain("Cannot rebalance different creatures stacks!"))
			)
			{
				return false;
			}

			if (notRemovable(sl1.army))
			{
				if (s1->getStackCount(p1) > countLeftOnSrc)
					return false;
			}
			else if (notRemovable(sl2.army))
			{
				if (s2->getStackCount(p1) < countLeftOnSrc)
					return false;
			}

			moveStack(sl1, sl2, countToMove);
			//S2.slots[p2]->count = val;
			//S1.slots[p1]->count = total - val;
		}
		else //split one stack to the two
		{
			if (s1->getStackCount(p1) < val)//not enough creatures
			{
				complain("Cannot split that stack, not enough creatures!");
				return false;
			}

			if (notRemovable(sl1.army))
				return false;

			moveStack(sl1, sl2, val);
		}

	}
	return true;
}

PlayerColor CGameHandler::getPlayerAt(std::shared_ptr<CConnection> c) const
{
	std::set<PlayerColor> all;
	for (auto i=connections.cbegin(); i!=connections.cend(); i++)
		if(vstd::contains(i->second, c))
			all.insert(i->first);

	switch(all.size())
	{
	case 0:
		return PlayerColor::NEUTRAL;
	case 1:
		return *all.begin();
	default:
		{
			//if we have more than one player at this connection, try to pick active one
			if (vstd::contains(all, gs->currentPlayer))
				return gs->currentPlayer;
			else
				return PlayerColor::CANNOT_DETERMINE; //cannot say which player is it
		}
	}
}

bool CGameHandler::disbandCreature(ObjectInstanceID id, SlotID pos)
{
	const CArmedInstance * s1 = static_cast<const CArmedInstance *>(getObjInstance(id));
	if (!vstd::contains(s1->stacks,pos))
	{
		complain("Illegal call to disbandCreature - no such stack in army!");
		return false;
	}

	eraseStack(StackLocation(s1, pos));
	return true;
}

bool CGameHandler::buildStructure(ObjectInstanceID tid, BuildingID requestedID, bool force)
{
	const CGTownInstance * t = getTown(tid);
	if (!t)
		COMPLAIN_RETF("No such town (ID=%s)!", tid);
	if (!t->town->buildings.count(requestedID))
		COMPLAIN_RETF("Town of faction %s does not have info about building ID=%s!", t->town->faction->name % tid);
	if (t->hasBuilt(requestedID))
		COMPLAIN_RETF("Building %s is already built in %s", t->town->buildings.at(requestedID)->Name() % t->name);

	const CBuilding * requestedBuilding = t->town->buildings.at(requestedID);

	//Vector with future list of built building and buildings in auto-mode that are not yet built.
	std::vector<const CBuilding*> remainingAutoBuildings;
	std::set<BuildingID> buildingsThatWillBe;

	//Check validity of request
	if (!force)
	{
		switch (requestedBuilding->mode)
		{
		case CBuilding::BUILD_NORMAL :
			if (canBuildStructure(t, requestedID) != EBuildingState::ALLOWED)
				COMPLAIN_RET("Cannot build that building!");
			break;

		case CBuilding::BUILD_AUTO   :
		case CBuilding::BUILD_SPECIAL:
			COMPLAIN_RET("This building can not be constructed normally!");

		case CBuilding::BUILD_GRAIL  :
			if (requestedBuilding->mode == CBuilding::BUILD_GRAIL) //needs grail
			{
				if (!t->visitingHero || !t->visitingHero->hasArt(ArtifactID::GRAIL))
					COMPLAIN_RET("Cannot build this without grail!")
				else
					removeArtifact(ArtifactLocation(t->visitingHero, t->visitingHero->getArtPos(ArtifactID::GRAIL, false)));
			}
			break;
		}
	}

	//Performs stuff that has to be done before new building is built
	auto processBeforeBuiltStructure = [t, this](const BuildingID buildingID)
	{
		if (buildingID >= BuildingID::DWELL_FIRST) //dwelling
		{
			int level = (buildingID - BuildingID::DWELL_FIRST) % GameConstants::CREATURES_PER_TOWN;
			int upgradeNumber = (buildingID - BuildingID::DWELL_FIRST) / GameConstants::CREATURES_PER_TOWN;

			if (upgradeNumber >= t->town->creatures.at(level).size())
			{
				complain(boost::str(boost::format("Error ecountered when building dwelling (bid=%s):"
													"no creature found (upgrade number %d, level %d!")
												% buildingID % upgradeNumber % level));
				return;
			}

			CCreature * crea = VLC->creh->creatures.at(t->town->creatures.at(level).at(upgradeNumber));

			SetAvailableCreatures ssi;
			ssi.tid = t->id;
			ssi.creatures = t->creatures;
			if (ssi.creatures[level].second.empty()) // first creature in a dwelling
				ssi.creatures[level].first = crea->growth;
			ssi.creatures[level].second.push_back(crea->idNumber);
			sendAndApply(&ssi);
		}
		if (t->subID == ETownType::DUNGEON && buildingID == BuildingID::PORTAL_OF_SUMMON)
		{
			setPortalDwelling(t);
		}
	};

	//Performs stuff that has to be done after new building is built
	auto processAfterBuiltStructure = [t, this](const BuildingID buildingID)
	{
		if (buildingID <= BuildingID::MAGES_GUILD_5 || //it's mage guild
			(t->subID == ETownType::TOWER && buildingID == BuildingID::LIBRARY) ||
			(t->subID == ETownType::CONFLUX && buildingID == BuildingID::GRAIL))
		{
			if (t->visitingHero)
				giveSpells(t,t->visitingHero);
			if (t->garrisonHero)
				giveSpells(t,t->garrisonHero);
		}
	};

	//Checks if all requirements will be met with expected building list "buildingsThatWillBe"
	auto areRequirementsFullfilled = [&](const BuildingID & buildID)
	{
		return buildingsThatWillBe.count(buildID);
	};

	//Init the vectors
	for (auto & build : t->town->buildings)
	{
		if (t->hasBuilt(build.first))
			buildingsThatWillBe.insert(build.first);
		else
		{
			if (build.second->mode == CBuilding::BUILD_AUTO) //not built auto building
				remainingAutoBuildings.push_back(build.second);
		}
	}

	//Prepare structure (list of building ids will be filled later)
	NewStructures ns;
	ns.tid = tid;
	ns.builded = force ? t->builded : (t->builded+1);

	std::queue<const CBuilding*> buildingsToAdd;
	buildingsToAdd.push(requestedBuilding);

	while(!buildingsToAdd.empty())
	{
		auto b = buildingsToAdd.front();
		buildingsToAdd.pop();

		ns.bid.insert(b->bid);
		buildingsThatWillBe.insert(b->bid);
		remainingAutoBuildings -= b;

		for(auto autoBuilding : remainingAutoBuildings)
		{
			auto actualRequirements = t->genBuildingRequirements(autoBuilding->bid);

			if(actualRequirements.test(areRequirementsFullfilled))
				buildingsToAdd.push(autoBuilding);
		}
	}

	// FIXME: it's done before NewStructures applied because otherwise town window wont be properly updated on client. That should be actually fixed on client and not on server.
	for (auto builtID : ns.bid)
		processBeforeBuiltStructure(builtID);

	//Take cost
	if (!force)
	{
		giveResources(t->tempOwner, -requestedBuilding->resources);
	}

	//We know what has been built, appluy changes. Do this as final step to properly update town window
	sendAndApply(&ns);

	//Other post-built events. To some logic like giving spells to work gamestate changes for new building must be already in place!
	for (auto builtID : ns.bid)
		processAfterBuiltStructure(builtID);

	// now when everything is built - reveal tiles for lookout tower
	FoWChange fw;
	fw.player = t->tempOwner;
	fw.mode = 1;
	getTilesInRange(fw.tiles, t->getSightCenter(), t->getSightRadius(), t->tempOwner, 1);
	sendAndApply(&fw);

	if (t->visitingHero)
		vistiCastleObjects (t, t->visitingHero);
	if (t->garrisonHero)
		vistiCastleObjects (t, t->garrisonHero);

	checkVictoryLossConditionsForPlayer(t->tempOwner);
	return true;
}
bool CGameHandler::razeStructure (ObjectInstanceID tid, BuildingID bid)
{
///incomplete, simply erases target building
	const CGTownInstance * t = getTown(tid);
	if (!vstd::contains(t->builtBuildings, bid))
		return false;
	RazeStructures rs;
	rs.tid = tid;
	rs.bid.insert(bid);
	rs.destroyed = t->destroyed + 1;
	sendAndApply(&rs);
//TODO: Remove dwellers
// 	if (t->subID == 4 && bid == 17) //Veil of Darkness
// 	{
// 		RemoveBonus rb(RemoveBonus::TOWN);
// 		rb.whoID = t->id;
// 		rb.source = Bonus::TOWN_STRUCTURE;
// 		rb.id = 17;
// 		sendAndApply(&rb);
// 	}
	return true;
}

void CGameHandler::sendMessageToAll(const std::string &message)
{
	SystemMessage sm;
	sm.text = message;
	sendToAllClients(&sm);
}

bool CGameHandler::recruitCreatures(ObjectInstanceID objid, ObjectInstanceID dstid, CreatureID crid, ui32 cram, si32 fromLvl)
{
	const CGDwelling * dw = static_cast<const CGDwelling *>(getObj(objid));
	const CArmedInstance *dst = nullptr;
	const CCreature *c = VLC->creh->creatures.at(crid);
	const bool warMachine = c->warMachine != ArtifactID::NONE;

	//TODO: test for owning
	//TODO: check if dst can recruit objects (e.g. hero is actually visiting object, town and source are same, etc)
	dst = dynamic_cast<const CArmedInstance*>(getObj(dstid));

	assert(dw && dst);

	//verify
	bool found = false;
	int level = 0;

	for (; level < dw->creatures.size(); level++) //iterate through all levels
	{
		if ((fromLvl != -1) && (level !=fromLvl))
			continue;
		const auto &cur = dw->creatures.at(level); //current level info <amount, list of cr. ids>
		int i = 0;
		for (; i < cur.second.size(); i++) //look for crid among available creatures list on current level
			if (cur.second.at(i) == crid)
				break;

		if (i < cur.second.size())
		{
			found = true;
			cram = std::min(cram, cur.first); //reduce recruited amount up to available amount
			break;
		}
	}
	SlotID slot = dst->getSlotFor(crid);

	if ((!found && complain("Cannot recruit: no such creatures!"))
		|| (cram  >  VLC->creh->creatures.at(crid)->maxAmount(getPlayer(dst->tempOwner)->resources) && complain("Cannot recruit: lack of resources!"))
		|| (cram<=0  &&  complain("Cannot recruit: cram <= 0!"))
		|| (!slot.validSlot()  && !warMachine && complain("Cannot recruit: no available slot!")))
	{
		return false;
	}

	//recruit
	giveResources(dst->tempOwner, -(c->cost * cram));

	SetAvailableCreatures sac;
	sac.tid = objid;
	sac.creatures = dw->creatures;
	sac.creatures[level].first -= cram;
	sendAndApply(&sac);

	if (warMachine)
	{
		const CGHeroInstance *h = dynamic_cast<const CGHeroInstance*>(dst);

		COMPLAIN_RET_FALSE_IF(!h, "Only hero can buy war machines");

		ArtifactID artId = c->warMachine;

		COMPLAIN_RET_FALSE_IF(artId == ArtifactID::CATAPULT, "Catapult cannot be recruited!");

		const CArtifact * art = artId.toArtifact();

		COMPLAIN_RET_FALSE_IF(nullptr == art, "Invalid war machine artifact");

		return giveHeroNewArtifact(h, art);
	}
	else
	{
		addToSlot(StackLocation(dst, slot), c, cram);
	}
	return true;
}

bool CGameHandler::upgradeCreature(ObjectInstanceID objid, SlotID pos, CreatureID upgID)
{
	const CArmedInstance * obj = static_cast<const CArmedInstance *>(getObjInstance(objid));
	if (!obj->hasStackAtSlot(pos))
	{
		COMPLAIN_RET("Cannot upgrade, no stack at slot " + boost::to_string(pos));
	}
	UpgradeInfo ui;
	getUpgradeInfo(obj, pos, ui);
	PlayerColor player = obj->tempOwner;
	const PlayerState *p = getPlayer(player);
	int crQuantity = obj->stacks.at(pos)->count;
	int newIDpos= vstd::find_pos(ui.newID, upgID);//get position of new id in UpgradeInfo

	//check if upgrade is possible
	if ((ui.oldID<0 || newIDpos == -1) && complain("That upgrade is not possible!"))
	{
		return false;
	}
	TResources totalCost = ui.cost.at(newIDpos) * crQuantity;

	//check if player has enough resources
	if (!p->resources.canAfford(totalCost))
		COMPLAIN_RET("Cannot upgrade, not enough resources!");

	//take resources
	giveResources(player, -totalCost);

	//upgrade creature
	changeStackType(StackLocation(obj, pos), VLC->creh->creatures.at(upgID));
	return true;
}

bool CGameHandler::changeStackType(const StackLocation &sl, const CCreature *c)
{
	if (!sl.army->hasStackAtSlot(sl.slot))
		COMPLAIN_RET("Cannot find a stack to change type");

	SetStackType sst;
	sst.army = sl.army->id;
	sst.slot = sl.slot;
	sst.type = c->idNumber;
	sendAndApply(&sst);
	return true;
}

void CGameHandler::moveArmy(const CArmedInstance *src, const CArmedInstance *dst, bool allowMerging)
{
	assert(src->canBeMergedWith(*dst, allowMerging));
	while(src->stacksCount())//while there are unmoved creatures
	{
		auto i = src->Slots().begin(); //iterator to stack to move
		StackLocation sl(src, i->first); //location of stack to move

		SlotID pos = dst->getSlotFor(i->second->type);
		if (!pos.validSlot())
		{
			//try to merge two other stacks to make place
			std::pair<SlotID, SlotID> toMerge;
			if (dst->mergableStacks(toMerge, i->first) && allowMerging)
			{
				moveStack(StackLocation(dst, toMerge.first), StackLocation(dst, toMerge.second)); //merge toMerge.first into toMerge.second
				assert(!dst->hasStackAtSlot(toMerge.first)); //we have now a new free slot
				moveStack(sl, StackLocation(dst, toMerge.first)); //move stack to freed slot
			}
			else
			{
				complain("Unexpected failure during an attempt to move army from " + src->nodeName() + " to " + dst->nodeName() + "!");
				return;
			}
		}
		else
		{
			moveStack(sl, StackLocation(dst, pos));
		}
	}
}

bool CGameHandler::garrisonSwap(ObjectInstanceID tid)
{
	const CGTownInstance * town = getTown(tid);
	if (!town->garrisonHero && town->visitingHero) //visiting => garrison, merge armies: town army => hero army
	{

		if (!town->visitingHero->canBeMergedWith(*town))
		{
			complain("Cannot make garrison swap, not enough free slots!");
			return false;
		}

		moveArmy(town, town->visitingHero, true);

		SetHeroesInTown intown;
		intown.tid = tid;
		intown.visiting = ObjectInstanceID();
		intown.garrison = town->visitingHero->id;
		sendAndApply(&intown);
		return true;
	}
	else if (town->garrisonHero && !town->visitingHero) //move hero out of the garrison
	{
		//check if moving hero out of town will break 8 wandering heroes limit
		if (getHeroCount(town->garrisonHero->tempOwner,false) >= 8)
		{
			complain("Cannot move hero out of the garrison, there are already 8 wandering heroes!");
			return false;
		}

		SetHeroesInTown intown;
		intown.tid = tid;
		intown.garrison = ObjectInstanceID();
		intown.visiting =  town->garrisonHero->id;
		sendAndApply(&intown);
		return true;
	}
	else if (!!town->garrisonHero && town->visitingHero) //swap visiting and garrison hero
	{
		SetHeroesInTown intown;
		intown.tid = tid;
		intown.garrison = town->visitingHero->id;
		intown.visiting =  town->garrisonHero->id;
		sendAndApply(&intown);
		return true;
	}
	else
	{
		complain("Cannot swap garrison hero!");
		return false;
	}
}

// With the amount of changes done to the function, it's more like transferArtifacts.
// Function moves artifact from src to dst. If dst is not a backpack and is already occupied, old dst art goes to backpack and is replaced.
bool CGameHandler::moveArtifact(const ArtifactLocation &al1, const ArtifactLocation &al2)
{
	ArtifactLocation src = al1, dst = al2;
	const PlayerColor srcPlayer = src.owningPlayer(), dstPlayer = dst.owningPlayer();
	const CArmedInstance *srcObj = src.relatedObj(), *dstObj = dst.relatedObj();

	// Make sure exchange is even possible between the two heroes.
	if (!isAllowedExchange(srcObj->id, dstObj->id))
		COMPLAIN_RET("That heroes cannot make any exchange!");

	const CArtifactInstance *srcArtifact = src.getArt();
	const CArtifactInstance *destArtifact = dst.getArt();

	if (srcArtifact == nullptr)
		COMPLAIN_RET("No artifact to move!");
	if (destArtifact && srcPlayer != dstPlayer)
		COMPLAIN_RET("Can't touch artifact on hero of another player!");

	// Check if src/dest slots are appropriate for the artifacts exchanged.
	// Moving to the backpack is always allowed.
	if ((!srcArtifact || dst.slot < GameConstants::BACKPACK_START)
		&& srcArtifact && !srcArtifact->canBePutAt(dst, true))
		COMPLAIN_RET("Cannot move artifact!");

	auto srcSlot = src.getSlot();
	auto dstSlot = dst.getSlot();

	if ((srcSlot && srcSlot->locked) || (dstSlot && dstSlot->locked))
		COMPLAIN_RET("Cannot move artifact locks.");

	if (dst.slot >= GameConstants::BACKPACK_START && srcArtifact->artType->isBig())
		COMPLAIN_RET("Cannot put big artifacts in backpack!");
	if (src.slot == ArtifactPosition::MACH4 || dst.slot == ArtifactPosition::MACH4)
		COMPLAIN_RET("Cannot move catapult!");

	if (dst.slot >= GameConstants::BACKPACK_START)
		vstd::amin(dst.slot, ArtifactPosition(GameConstants::BACKPACK_START + dst.getHolderArtSet()->artifactsInBackpack.size()));

	if (src.slot == dst.slot  &&  src.artHolder == dst.artHolder)
		COMPLAIN_RET("Won't move artifact: Dest same as source!");

	if (dst.slot < GameConstants::BACKPACK_START  &&  destArtifact) //moving art to another slot
	{
		//old artifact must be removed first
		moveArtifact(dst, ArtifactLocation(dst.artHolder, ArtifactPosition(
			dst.getHolderArtSet()->artifactsInBackpack.size() + GameConstants::BACKPACK_START)));
	}

	MoveArtifact ma;
	ma.src = src;
	ma.dst = dst;
	sendAndApply(&ma);
	return true;
}

/**
 * Assembles or disassembles a combination artifact.
 * @param heroID ID of hero holding the artifact(s).
 * @param artifactSlot The worn slot ID of the combination- or constituent artifact.
 * @param assemble True for assembly operation, false for disassembly.
 * @param assembleTo If assemble is true, this represents the artifact ID of the combination
 * artifact to assemble to. Otherwise it's not used.
 */
bool CGameHandler::assembleArtifacts (ObjectInstanceID heroID, ArtifactPosition artifactSlot, bool assemble, ArtifactID assembleTo)
{
	const CGHeroInstance * hero = getHero(heroID);
	const CArtifactInstance *destArtifact = hero->getArt(artifactSlot);

	if (!destArtifact)
		COMPLAIN_RET("assembleArtifacts: there is no such artifact instance!");

	if (assemble)
	{
		CArtifact *combinedArt = VLC->arth->artifacts[assembleTo];
		if (!combinedArt->constituents)
			COMPLAIN_RET("assembleArtifacts: Artifact being attempted to assemble is not a combined artifacts!");
		if (!vstd::contains(destArtifact->assemblyPossibilities(hero), combinedArt))
			COMPLAIN_RET("assembleArtifacts: It's impossible to assemble requested artifact!");

		AssembledArtifact aa;
		aa.al = ArtifactLocation(hero, artifactSlot);
		aa.builtArt = combinedArt;
		sendAndApply(&aa);
	}
	else
	{
		if (!destArtifact->artType->constituents)
			COMPLAIN_RET("assembleArtifacts: Artifact being attempted to disassemble is not a combined artifact!");

		DisassembledArtifact da;
		da.al = ArtifactLocation(hero, artifactSlot);
		sendAndApply(&da);
	}

	return true;
}

bool CGameHandler::buyArtifact(ObjectInstanceID hid, ArtifactID aid)
{
	const CGHeroInstance * hero = getHero(hid);
	COMPLAIN_RET_FALSE_IF(nullptr == hero, "Invalid hero index");
	const CGTownInstance * town = hero->visitedTown;
	COMPLAIN_RET_FALSE_IF(nullptr == town, "Hero not in town");

	if (aid==ArtifactID::SPELLBOOK)
	{
		if ((!town->hasBuilt(BuildingID::MAGES_GUILD_1) && complain("Cannot buy a spellbook, no mage guild in the town!"))
		    || (getResource(hero->getOwner(), Res::GOLD) < GameConstants::SPELLBOOK_GOLD_COST && complain("Cannot buy a spellbook, not enough gold!"))
		    || (hero->getArt(ArtifactPosition::SPELLBOOK) && complain("Cannot buy a spellbook, hero already has a one!"))
		   )
			return false;

		giveResource(hero->getOwner(),Res::GOLD,-GameConstants::SPELLBOOK_GOLD_COST);
		giveHeroNewArtifact(hero, VLC->arth->artifacts[ArtifactID::SPELLBOOK], ArtifactPosition::SPELLBOOK);
		assert(hero->getArt(ArtifactPosition::SPELLBOOK));
		giveSpells(town,hero);
		return true;
	}
	else
	{
		const CArtifact * art = aid.toArtifact();
		COMPLAIN_RET_FALSE_IF(nullptr == art, "Invalid artifact index to buy");
		COMPLAIN_RET_FALSE_IF(art->warMachine == CreatureID::NONE, "War machine artifact required");
		COMPLAIN_RET_FALSE_IF(hero->hasArt(aid),"Hero already has this machine!");
		const int price = art->price;
		COMPLAIN_RET_FALSE_IF(getPlayer(hero->getOwner())->resources.at(Res::GOLD) < price, "Not enough gold!");

		if  ((town->hasBuilt(BuildingID::BLACKSMITH) && town->town->warMachine == aid)
		 || ((town->hasBuilt(BuildingID::BALLISTA_YARD, ETownType::STRONGHOLD)) && aid == ArtifactID::BALLISTA))
		{
			giveResource(hero->getOwner(),Res::GOLD,-price);
			return giveHeroNewArtifact(hero, art);
		}
		else
			COMPLAIN_RET("This machine is unavailable here!");
	}
}

bool CGameHandler::buyArtifact(const IMarket *m, const CGHeroInstance *h, Res::ERes rid, ArtifactID aid)
{
	if(!h)
		COMPLAIN_RET("Only hero can buy artifacts!");

	if (!vstd::contains(m->availableItemsIds(EMarketMode::RESOURCE_ARTIFACT), aid))
		COMPLAIN_RET("That artifact is unavailable!");

	int b1, b2;
	m->getOffer(rid, aid, b1, b2, EMarketMode::RESOURCE_ARTIFACT);

	if (getResource(h->tempOwner, rid) < b1)
		COMPLAIN_RET("You can't afford to buy this artifact!");

	giveResource(h->tempOwner, rid, -b1);

	SetAvailableArtifacts saa;
	if (m->o->ID == Obj::TOWN)
	{
		saa.id = -1;
		saa.arts = CGTownInstance::merchantArtifacts;
	}
	else if (const CGBlackMarket *bm = dynamic_cast<const CGBlackMarket *>(m->o)) //black market
	{
		saa.id = bm->id.getNum();
		saa.arts = bm->artifacts;
	}
	else
		COMPLAIN_RET("Wrong marktet...");

	bool found = false;
	for (const CArtifact *&art : saa.arts)
	{
		if (art && art->id == aid)
		{
			art = nullptr;
			found = true;
			break;
		}
	}

	if (!found)
		COMPLAIN_RET("Cannot find selected artifact on the list");

	sendAndApply(&saa);

	giveHeroNewArtifact(h, VLC->arth->artifacts[aid], ArtifactPosition::FIRST_AVAILABLE);
	return true;
}

bool CGameHandler::sellArtifact(const IMarket *m, const CGHeroInstance *h, ArtifactInstanceID aid, Res::ERes rid)
{
	COMPLAIN_RET_FALSE_IF((!h), "Only hero can sell artifacts!");
	const CArtifactInstance *art = h->getArtByInstanceId(aid);
	COMPLAIN_RET_FALSE_IF((!art), "There is no artifact to sell!");
	COMPLAIN_RET_FALSE_IF((!art->artType->isTradable()), "Cannot sell a war machine or spellbook!");

	int resVal = 0, dump = 1;
	m->getOffer(art->artType->id, rid, dump, resVal, EMarketMode::ARTIFACT_RESOURCE);

	removeArtifact(ArtifactLocation(h, h->getArtPos(art)));
	giveResource(h->tempOwner, rid, resVal);
	return true;
}

bool CGameHandler::buySecSkill(const IMarket *m, const CGHeroInstance *h, SecondarySkill skill)
{
	if (!h)
		COMPLAIN_RET("You need hero to buy a skill!");

	if (h->getSecSkillLevel(SecondarySkill(skill)))
		COMPLAIN_RET("Hero already know this skill");

	if (!h->canLearnSkill())
		COMPLAIN_RET("Hero can't learn any more skills");

	if (h->type->heroClass->secSkillProbability.at(skill)==0)//can't learn this skill (like necromancy for most of non-necros)
		COMPLAIN_RET("The hero can't learn this skill!");

	if (!vstd::contains(m->availableItemsIds(EMarketMode::RESOURCE_SKILL), skill))
		COMPLAIN_RET("That skill is unavailable!");

	if (getResource(h->tempOwner, Res::GOLD) < GameConstants::SKILL_GOLD_COST)//TODO: remove hardcoded resource\summ?
		COMPLAIN_RET("You can't afford to buy this skill");

	giveResource(h->tempOwner, Res::GOLD, -GameConstants::SKILL_GOLD_COST);

	changeSecSkill(h, skill, 1, true);
	return true;
}

bool CGameHandler::tradeResources(const IMarket *market, ui32 val, PlayerColor player, ui32 id1, ui32 id2)
{
	TResourceCap r1 = getPlayer(player)->resources.at(id1);

	vstd::amin(val, r1); //can't trade more resources than have

	int b1, b2; //base quantities for trade
	market->getOffer(id1, id2, b1, b2, EMarketMode::RESOURCE_RESOURCE);
	int units = val / b1; //how many base quantities we trade

	if (val%b1) //all offered units of resource should be used, if not -> somewhere in calculations must be an error
	{
		COMPLAIN_RET("Invalid deal, not all offered units of resource were used.");
	}

	giveResource(player, static_cast<Res::ERes>(id1), - b1 * units);
	giveResource(player, static_cast<Res::ERes>(id2), b2 * units);

	return true;
}

bool CGameHandler::sellCreatures(ui32 count, const IMarket *market, const CGHeroInstance * hero, SlotID slot, Res::ERes resourceID)
{
	if(!hero)
		COMPLAIN_RET("Only hero can sell creatures!");
	if (!vstd::contains(hero->Slots(), slot))
		COMPLAIN_RET("Hero doesn't have any creature in that slot!");

	const CStackInstance &s = hero->getStack(slot);

	if (s.count < count //can't sell more creatures than have
		|| (hero->stacksCount() == 1 && hero->needsLastStack() && s.count == count)) //can't sell last stack
	{
		COMPLAIN_RET("Not enough creatures in army!");
	}

	int b1, b2; //base quantities for trade
	market->getOffer(s.type->idNumber, resourceID, b1, b2, EMarketMode::CREATURE_RESOURCE);
	int units = count / b1; //how many base quantities we trade

	if (count%b1) //all offered units of resource should be used, if not -> somewhere in calculations must be an error
	{
		//TODO: complain?
		assert(0);
	}

	changeStackCount(StackLocation(hero, slot), -count);

	giveResource(hero->tempOwner, resourceID, b2 * units);

	return true;
}

bool CGameHandler::transformInUndead(const IMarket *market, const CGHeroInstance * hero, SlotID slot)
{
	const CArmedInstance *army = nullptr;
	if (hero)
		army = hero;
	else
		army = dynamic_cast<const CGTownInstance *>(market->o);

	if (!army)
		COMPLAIN_RET("Incorrect call to transform in undead!");
	if (!army->hasStackAtSlot(slot))
		COMPLAIN_RET("Army doesn't have any creature in that slot!");


	const CStackInstance &s = army->getStack(slot);

	//resulting creature - bone dragons or skeletons
	CreatureID resCreature = CreatureID::SKELETON;

	if ((s.hasBonusOfType(Bonus::DRAGON_NATURE)
			&& !(s.hasBonusOfType(Bonus::UNDEAD)))
			|| (s.getCreatureID() == CreatureID::HYDRA)
			|| (s.getCreatureID() == CreatureID::CHAOS_HYDRA))
		resCreature = CreatureID::BONE_DRAGON;
	changeStackType(StackLocation(army, slot), resCreature.toCreature());
	return true;
}

bool CGameHandler::sendResources(ui32 val, PlayerColor player, Res::ERes r1, PlayerColor r2)
{
	const PlayerState *p2 = getPlayer(r2, false);
	if (!p2  ||  p2->status != EPlayerStatus::INGAME)
	{
		complain("Dest player must be in game!");
		return false;
	}

	TResourceCap curRes1 = getPlayer(player)->resources.at(r1);

	vstd::amin(val, curRes1);

	giveResource(player, r1, -val);
	giveResource(r2, r1, val);

	return true;
}

bool CGameHandler::setFormation(ObjectInstanceID hid, ui8 formation)
{
	const CGHeroInstance *h = getHero(hid);
	if (!h)
	{
		logGlobal->error("Hero doesn't exist!");
		return false;
	}

	ChangeFormation cf;
	cf.hid = hid;
	cf.formation = formation;
	sendAndApply(&cf);

	return true;
}

bool CGameHandler::hireHero(const CGObjectInstance *obj, ui8 hid, PlayerColor player)
{
	const PlayerState * p = getPlayer(player);
	const CGTownInstance * t = getTown(obj->id);

	//common preconditions
//	if ((p->resources.at(Res::GOLD)<GOLD_NEEDED  && complain("Not enough gold for buying hero!"))
//		|| (getHeroCount(player, false) >= GameConstants::MAX_HEROES_PER_PLAYER && complain("Cannot hire hero, only 8 wandering heroes are allowed!")))
	if ((p->resources.at(Res::GOLD) < GameConstants::HERO_GOLD_COST && complain("Not enough gold for buying hero!"))
		|| ((!t) && (getHeroCount(player, false) >= VLC->modh->settings.MAX_HEROES_ON_MAP_PER_PLAYER && complain("Cannot hire hero, too many wandering heroes already!")))
		|| ((t) && (getHeroCount(player, true) >= VLC->modh->settings.MAX_HEROES_AVAILABLE_PER_PLAYER && complain("Cannot hire hero, too many heroes garrizoned and wandering already!"))))
	{
		return false;
	}

	if (t) //tavern in town
	{
		if ((!t->hasBuilt(BuildingID::TAVERN) && complain("No tavern!"))
			 || (t->visitingHero  && complain("There is visiting hero - no place!")))
		{
			return false;
		}
	}
	else if (obj->ID == Obj::TAVERN)
	{
		if (getTile(obj->visitablePos())->visitableObjects.back() != obj && complain("Tavern entry must be unoccupied!"))
		{
			return false;
		}
	}

	const CGHeroInstance *nh = p->availableHeroes.at(hid);
	if (!nh)
	{
		complain ("Hero is not available for hiring!");
		return false;
	}

	HeroRecruited hr;
	hr.tid = obj->id;
	hr.hid = nh->subID;
	hr.player = player;
	hr.tile = obj->visitablePos() + nh->getVisitableOffset();
	sendAndApply(&hr);

	std::map<ui32, ConstTransitivePtr<CGHeroInstance> > pool = gs->unusedHeroesFromPool();

	const CGHeroInstance *theOtherHero = p->availableHeroes.at(!hid);
	const CGHeroInstance *newHero = nullptr;
	if (theOtherHero) //on XXL maps all heroes can be imprisoned :(
	{
		newHero = gs->hpool.pickHeroFor(false, player, getNativeTown(player), pool, getRandomGenerator(), theOtherHero->type->heroClass);
	}

	SetAvailableHeroes sah;
	sah.player = player;

	if (newHero)
	{
		sah.hid[hid] = newHero->subID;
		sah.army[hid].clear();
		sah.army[hid].setCreature(SlotID(0), newHero->type->initialArmy[0].creature, 1);
	}
	else
	{
		sah.hid[hid] = -1;
	}

	sah.hid[!hid] = theOtherHero ? theOtherHero->subID : -1;
	sendAndApply(&sah);

	giveResource(player, Res::GOLD, -GameConstants::HERO_GOLD_COST);

	if (t)
	{
		vistiCastleObjects (t, nh);
		giveSpells (t,nh);
	}
	return true;
}

bool CGameHandler::queryReply(QueryID qid, const JsonNode & answer, PlayerColor player)
{
	boost::unique_lock<boost::recursive_mutex> lock(gsm);

	logGlobal->trace("Player %s attempts answering query %d with answer:", player, qid);
	logGlobal->trace(answer.toJson());

	auto topQuery = queries.topQuery(player);
	COMPLAIN_RET_FALSE_IF(!topQuery, "This player doesn't have any queries!");
	COMPLAIN_RET_FALSE_IF(topQuery->queryID != qid, "This player top query has different ID!");
	COMPLAIN_RET_FALSE_IF(!topQuery->endsByPlayerAnswer(), "This query cannot be ended by player's answer!");

	topQuery->setReply(answer);
	queries.popQuery(topQuery);
	return true;
}

static EndAction end_action;

void CGameHandler::updateGateState()
{
	BattleUpdateGateState db;
	db.state = gs->curB->si.gateState;
	if (gs->curB->si.wallState[EWallPart::GATE] == EWallState::DESTROYED)
	{
		db.state = EGateState::DESTROYED;
	}
	else if (db.state == EGateState::OPENED)
	{
		if (!gs->curB->battleGetStackByPos(BattleHex(ESiegeHex::GATE_OUTER), false) &&
			!gs->curB->battleGetStackByPos(BattleHex(ESiegeHex::GATE_INNER), false))
		{
			if (gs->curB->town->subID == ETownType::FORTRESS)
			{
				if (!gs->curB->battleGetStackByPos(BattleHex(ESiegeHex::GATE_BRIDGE), false))
					db.state = EGateState::CLOSED;
			}
			else if (gs->curB->battleGetStackByPos(BattleHex(ESiegeHex::GATE_BRIDGE)))
				db.state = EGateState::BLOCKED;
			else
				db.state = EGateState::CLOSED;
		}
	}
	else if (gs->curB->battleGetStackByPos(BattleHex(ESiegeHex::GATE_BRIDGE), false))
		db.state = EGateState::BLOCKED;
	else
		db.state = EGateState::CLOSED;

	if (db.state != gs->curB->si.gateState)
		sendAndApply(&db);
}

bool CGameHandler::makeBattleAction(BattleAction &ba)
{
	bool ok = true;

	battle::Target target = ba.getTarget(gs->curB);

	const CStack * stack = battleGetStackByID(ba.stackNumber); //may be nullptr if action is not about stack

	const bool isAboutActiveStack = stack && (ba.stackNumber == gs->curB->getActiveStackID());

	logGlobal->trace("Making action: %s", ba.toString());

	switch(ba.actionType)
	{
	case EActionType::WALK: //walk
	case EActionType::DEFEND: //defend
	case EActionType::WAIT: //wait
	case EActionType::WALK_AND_ATTACK: //walk or attack
	case EActionType::SHOOT: //shoot
	case EActionType::CATAPULT: //catapult
	case EActionType::STACK_HEAL: //healing with First Aid Tent
	case EActionType::DAEMON_SUMMONING:
	case EActionType::MONSTER_SPELL:

		if (!stack)
		{
			complain("No such stack!");
			return false;
		}
		if (!stack->alive())
		{
			complain("This stack is dead: " + stack->nodeName());
			return false;
		}

		if (battleTacticDist())
		{
			if (stack && stack->side != battleGetTacticsSide())
			{
				complain("This is not a stack of side that has tactics!");
				return false;
			}
		}
		else if (!isAboutActiveStack)
		{
			complain("Action has to be about active stack!");
			return false;
		}
	}

	auto wrapAction = [this](BattleAction &ba)
	{
		StartAction startAction(ba);
		sendAndApply(&startAction);

		return vstd::makeScopeGuard([&]()
		{
			sendAndApply(&end_action);
		});
	};

	switch(ba.actionType)
	{
	case EActionType::END_TACTIC_PHASE: //wait
	case EActionType::BAD_MORALE:
	case EActionType::NO_ACTION:
		{
			auto wrapper = wrapAction(ba);
			break;
		}
	case EActionType::WALK:
		{
			auto wrapper = wrapAction(ba);
			if(target.size() < 1)
			{
				complain("Destination required for move action.");
				ok = false;
				break;
			}
			int walkedTiles = moveStack(ba.stackNumber, target.at(0).hexValue); //move
			if (!walkedTiles)
				complain("Stack failed movement!");
			break;
		}
	case EActionType::DEFEND:
		{
			//defensive stance, TODO: filter out spell boosts from bonus (stone skin etc.)
			SetStackEffect sse;
			Bonus defenseBonusToAdd(Bonus::STACK_GETS_TURN, Bonus::PRIMARY_SKILL, Bonus::OTHER, 20, -1, PrimarySkill::DEFENSE, Bonus::PERCENT_TO_ALL);
			Bonus bonus2(Bonus::STACK_GETS_TURN, Bonus::PRIMARY_SKILL, Bonus::OTHER, stack->valOfBonuses(Bonus::DEFENSIVE_STANCE),
				 -1, PrimarySkill::DEFENSE, Bonus::ADDITIVE_VALUE);
			Bonus alternativeWeakCreatureBonus(Bonus::STACK_GETS_TURN, Bonus::PRIMARY_SKILL, Bonus::OTHER, 1, -1, PrimarySkill::DEFENSE, Bonus::ADDITIVE_VALUE);

			BonusList defence = *stack->getBonuses(Selector::typeSubtype(Bonus::PRIMARY_SKILL, PrimarySkill::DEFENSE));
			int oldDefenceValue = defence.totalValue();

			defence.push_back(std::make_shared<Bonus>(defenseBonusToAdd));
			defence.push_back(std::make_shared<Bonus>(bonus2));

			int difference = defence.totalValue() - oldDefenceValue;
			std::vector<Bonus> buffer;
			if(difference == 0) //give replacement bonus for creatures not reaching 5 defense points (20% of def becomes 0)
			{
				difference = 1;
				buffer.push_back(alternativeWeakCreatureBonus);
			}
			else
			{
				buffer.push_back(defenseBonusToAdd);
			}

			buffer.push_back(bonus2);

			MetaString text;
			stack->addText(text, MetaString::GENERAL_TXT, 120);
			stack->addNameReplacement(text);
			text.addReplacement(difference);
			sse.battleLog.push_back(text);
			sse.toUpdate.push_back(std::make_pair(ba.stackNumber, buffer));
			sendAndApply(&sse);

			//don't break - we share code with next case
		}
		FALLTHROUGH
	case EActionType::WAIT:
		{
			auto wrapper = wrapAction(ba);
			break;
		}
	case EActionType::RETREAT: //retreat/flee
		{
			if (!gs->curB->battleCanFlee(gs->curB->sides.at(ba.side).color))
				complain("Cannot retreat!");
			else
				setBattleResult(BattleResult::ESCAPE, !ba.side); //surrendering side loses
			break;
		}
	case EActionType::SURRENDER:
		{
			PlayerColor player = gs->curB->sides.at(ba.side).color;
			int cost = gs->curB->battleGetSurrenderCost(player);
			if (cost < 0)
				complain("Cannot surrender!");
			else if (getResource(player, Res::GOLD) < cost)
				complain("Not enough gold to surrender!");
			else
			{
				giveResource(player, Res::GOLD, -cost);
				setBattleResult(BattleResult::SURRENDER, !ba.side); //surrendering side loses
			}
			break;
		}
	case EActionType::WALK_AND_ATTACK: //walk or attack
		{
			auto wrapper = wrapAction(ba);

			if(!stack)
			{
				complain("No attacker");
				ok = false;
				break;
			}

			if(target.size() < 2)
			{
				complain("Two destinations required for attack action.");
				ok = false;
				break;
			}

			BattleHex attackPos = target.at(0).hexValue;
			BattleHex destinationTile = target.at(1).hexValue;
			const CStack * destinationStack = gs->curB->battleGetStackByPos(destinationTile, true);

			if(!destinationStack)
			{
				complain("Invalid target to attack");
				ok = false;
				break;
			}

			BattleHex startingPos = stack->getPosition();
			int distance = moveStack(ba.stackNumber, attackPos);

			logGlobal->trace("%s will attack %s", stack->nodeName(), destinationStack->nodeName());

			if(stack->getPosition() != attackPos //we wasn't able to reach destination tile
				&& !(stack->doubleWide() && (stack->getPosition() == attackPos.cloneInDirection(stack->destShiftDir(), false))) //nor occupy specified hex
				)
			{
				complain("We cannot move this stack to its destination " + stack->getCreature()->namePl);
				ok = false;
				break;
			}

			if(destinationStack && stack->ID == destinationStack->ID) //we should just move, it will be handled by following check
			{
				destinationStack = nullptr;
			}

			if(!destinationStack)
			{
				complain("Unit can not attack itself");
				ok = false;
				break;
			}

			if(!CStack::isMeleeAttackPossible(stack, destinationStack))
			{
				complain("Attack cannot be performed!");
				ok = false;
				break;
			}

			//attack
			int totalAttacks = stack->totalAttacks.getMeleeValue();

			const bool firstStrike = destinationStack->hasBonusOfType(Bonus::FIRST_STRIKE);
			const bool retaliation = destinationStack->ableToRetaliate();
			for (int i = 0; i < totalAttacks; ++i)
			{
				//first strike
				if(i == 0 && firstStrike && retaliation)
				{
					makeAttack(destinationStack, stack, 0, stack->getPosition(), true, false, true);
				}

				//move can cause death, eg. by walking into the moat, first strike can cause death as well
				if(stack->alive() && destinationStack->alive())
				{
					makeAttack(stack, destinationStack, (i ? 0 : distance), destinationTile, i==0, false, false);//no distance travelled on second attack
				}

				//counterattack
				//we check retaliation twice, so if it unblocked during attack it will work only on next attack
				if(stack->alive()
					&& !stack->hasBonusOfType(Bonus::BLOCKS_RETALIATION)
					&& (i == 0 && !firstStrike)
					&& retaliation && destinationStack->ableToRetaliate())
				{
					makeAttack(destinationStack, stack, 0, stack->getPosition(), true, false, true);
				}
			}

			//return
			if(stack->hasBonusOfType(Bonus::RETURN_AFTER_STRIKE)
				&& target.size() == 3
				&& startingPos != stack->getPosition()
				&& startingPos == target.at(2).hexValue
				&& stack->alive())
			{
				moveStack(ba.stackNumber, startingPos);
				//NOTE: curStack->ID == ba.stackNumber (rev 1431)
			}
			break;
		}
	case EActionType::SHOOT:
		{
			if(target.size() < 1)
			{
				complain("Destination required for shot action.");
				ok = false;
				break;
			}

			auto destination = target.at(0).hexValue;

			const CStack * destinationStack = gs->curB->battleGetStackByPos(destination);

			if (!gs->curB->battleCanShoot(stack, destination))
			{
				complain("Cannot shoot!");
				break;
			}
			if (!destinationStack)
			{
				complain("No target to shoot!");
				break;
			}

			auto wrapper = wrapAction(ba);

			makeAttack(stack, destinationStack, 0, destination, true, true, false);

			//ranged counterattack
			if (destinationStack->hasBonusOfType(Bonus::RANGED_RETALIATION)
				&& !stack->hasBonusOfType(Bonus::BLOCKS_RANGED_RETALIATION)
				&& destinationStack->ableToRetaliate()
				&& gs->curB->battleCanShoot(destinationStack, stack->getPosition())
				&& stack->alive()) //attacker may have died (fire shield)
			{
				makeAttack(destinationStack, stack, 0, stack->getPosition(), true, true, true);
			}

			//TODO: move to CUnitState
			//extra shot(s) for ballista, based on artillery skill
			if(stack->creatureIndex() == CreatureID::BALLISTA)
			{
				const CGHeroInstance * attackingHero = gs->curB->battleGetFightingHero(ba.side);

				if(attackingHero)
				{
					int ballistaBonusAttacks = attackingHero->valOfBonuses(Bonus::SECONDARY_SKILL_VAL2, SecondarySkill::ARTILLERY);
					while(destinationStack->alive() && ballistaBonusAttacks-- > 0)
					{
						makeAttack(stack, destinationStack, 0, destination, false, true, false);
					}
				}
			}
			//allow more than one additional attack

			int totalRangedAttacks = stack->totalAttacks.getRangedValue();

			for(int i = 1; i < totalRangedAttacks; ++i)
			{
				if(
					stack->alive()
					&& destinationStack->alive()
					&& stack->shots.canUse()
					)
				{
					makeAttack(stack, destinationStack, 0, destination, false, true, false);
				}
			}
			break;
		}
	case EActionType::CATAPULT:
		{
			//TODO: unify with spells::effects:Catapult
			auto getCatapultHitChance = [&](EWallPart::EWallPart part, const CHeroHandler::SBallisticsLevelInfo & sbi) -> int
			{
				switch(part)
				{
				case EWallPart::GATE:
					return sbi.gate;
				case EWallPart::KEEP:
					return sbi.keep;
				case EWallPart::BOTTOM_TOWER:
				case EWallPart::UPPER_TOWER:
					return sbi.tower;
				case EWallPart::BOTTOM_WALL:
				case EWallPart::BELOW_GATE:
				case EWallPart::OVER_GATE:
				case EWallPart::UPPER_WALL:
					return sbi.wall;
				default:
					return 0;
				}
			};

			auto wrapper = wrapAction(ba);

			if(target.size() < 1)
			{
				complain("Destination required for catapult action.");
				ok = false;
				break;
			}
			auto destination = target.at(0).hexValue;

			const CGHeroInstance * attackingHero = gs->curB->battleGetFightingHero(ba.side);

			CHeroHandler::SBallisticsLevelInfo stackBallisticsParameters;
			if(stack->getCreature()->idNumber == CreatureID::CATAPULT)
				stackBallisticsParameters = VLC->heroh->ballistics.at(attackingHero->valOfBonuses(Bonus::SECONDARY_SKILL_PREMY, SecondarySkill::BALLISTICS));
			else
			{
				if(stack->hasBonusOfType(Bonus::CATAPULT_EXTRA_SHOTS)) //by design use advanced ballistics parameters with this bonus present, upg. cyclops use advanced ballistics, nonupg. use basic in OH3
				{
					stackBallisticsParameters = VLC->heroh->ballistics.at(2);
					stackBallisticsParameters.shots = 1; //skip default "2 shots" from adv. ballistics
				}
				else
					stackBallisticsParameters = VLC->heroh->ballistics.at(1);

				stackBallisticsParameters.shots += std::max(stack->valOfBonuses(Bonus::CATAPULT_EXTRA_SHOTS), 0); //0 is allowed minimum to let modders force advanced ballistics for "oneshotting creatures"
			}

			auto wallPart = gs->curB->battleHexToWallPart(destination);
			if (!gs->curB->isWallPartPotentiallyAttackable(wallPart))
			{
				complain("catapult tried to attack non-catapultable hex!");
				break;
			}

			//in successive iterations damage is dealt but not yet subtracted from wall's HPs
			auto &currentHP = gs->curB->si.wallState;

			if (currentHP.at(wallPart) == EWallState::DESTROYED  ||  currentHP.at(wallPart) == EWallState::NONE)
			{
				complain("catapult tried to attack already destroyed wall part!");
				break;
			}

			for (int g=0; g<stackBallisticsParameters.shots; ++g)
			{
				bool hitSuccessfull = false;
				auto attackedPart = wallPart;

				do // catapult has chance to attack desired target. Otherwise - attacks randomly
				{
					if (currentHP.at(attackedPart) != EWallState::DESTROYED && // this part can be hit
					   currentHP.at(attackedPart) != EWallState::NONE &&
					   getRandomGenerator().nextInt(99) < getCatapultHitChance(attackedPart, stackBallisticsParameters))//hit is successful
					{
						hitSuccessfull = true;
					}
					else // select new target
					{
						std::vector<EWallPart::EWallPart> allowedTargets;
						for (size_t i=0; i< currentHP.size(); i++)
						{
							if(currentHP.at(i) != EWallState::DESTROYED &&
								currentHP.at(i) != EWallState::NONE)
								allowedTargets.push_back(EWallPart::EWallPart(i));
						}
						if (allowedTargets.empty())
							break;
						attackedPart = *RandomGeneratorUtil::nextItem(allowedTargets, getRandomGenerator());
					}
				}
				while (!hitSuccessfull);

				if (!hitSuccessfull) // break triggered - no target to shoot at
					break;

				CatapultAttack ca; //package for clients
				CatapultAttack::AttackInfo attack;
				attack.attackedPart = attackedPart;
				attack.destinationTile = destination;
				attack.damageDealt = 0;
				BattleUnitsChanged removeUnits;

				int dmgChance[] = { stackBallisticsParameters.noDmg, stackBallisticsParameters.oneDmg, stackBallisticsParameters.twoDmg }; //dmgChance[i] - chance for doing i dmg when hit is successful

				int dmgRand = getRandomGenerator().nextInt(99);
				//accumulating dmgChance
				dmgChance[1] += dmgChance[0];
				dmgChance[2] += dmgChance[1];
				//calculating dealt damage
				for (int damage = 0; damage < ARRAY_COUNT(dmgChance); ++damage)
				{
					if (dmgRand <= dmgChance[damage])
					{
						attack.damageDealt = damage;
						break;
					}
				}
				// attacked tile may have changed - update destination
				attack.destinationTile = gs->curB->wallPartToBattleHex(EWallPart::EWallPart(attack.attackedPart));

				logGlobal->trace("Catapult attacks %d dealing %d damage", (int)attack.attackedPart, (int)attack.damageDealt);

				//removing creatures in turrets / keep if one is destroyed
				if (currentHP.at(attackedPart) - attack.damageDealt <= 0 && (attackedPart == EWallPart::KEEP || //HP enum subtraction not intuitive, consider using SiegeInfo::applyDamage
					attackedPart == EWallPart::BOTTOM_TOWER || attackedPart == EWallPart::UPPER_TOWER))
				{
					int posRemove = -1;
					switch(attackedPart)
					{
					case EWallPart::KEEP:
						posRemove = -2;
						break;
					case EWallPart::BOTTOM_TOWER:
						posRemove = -3;
						break;
					case EWallPart::UPPER_TOWER:
						posRemove = -4;
						break;
					}

					for(auto & elem : gs->curB->stacks)
					{
						if(elem->initialPosition == posRemove)
						{
							removeUnits.changedStacks.emplace_back(elem->unitId(), UnitChanges::EOperation::REMOVE);
							break;
						}
					}
				}
				ca.attacker = ba.stackNumber;
				ca.attackedParts.push_back(attack);

				sendAndApply(&ca);

				if(!removeUnits.changedStacks.empty())
					sendAndApply(&removeUnits);
			}
			//finish by scope guard
			break;
		}
		case EActionType::STACK_HEAL: //healing with First Aid Tent
		{
			auto wrapper = wrapAction(ba);
			const CGHeroInstance * attackingHero = gs->curB->battleGetFightingHero(ba.side);
			const CStack * healer = gs->curB->battleGetStackByID(ba.stackNumber);

			if(target.size() < 1)
			{
				complain("Destination required for heal action.");
				ok = false;
				break;
			}

			const battle::Unit * destStack = nullptr;

			if(target.at(0).unitValue)
				destStack = target.at(0).unitValue;
			else
				destStack = gs->curB->battleGetStackByPos(target.at(0).hexValue);

			if(healer == nullptr || destStack == nullptr || !healer->hasBonusOfType(Bonus::HEALER))
			{
				complain("There is either no healer, no destination, or healer cannot heal :P");
			}
			else
			{
				int64_t toHeal = healer->getCount() * std::max(10, attackingHero->valOfBonuses(Bonus::SECONDARY_SKILL_PREMY, SecondarySkill::FIRST_AID));

				//TODO: allow resurrection for mods
				auto state = destStack->acquireState();
				state->heal(toHeal, EHealLevel::HEAL, EHealPower::PERMANENT);

				if(toHeal == 0)
				{
					logGlobal->warn("Nothing to heal");
				}
				else
				{
					BattleUnitsChanged pack;

					MetaString text;
					text.addTxt(MetaString::GENERAL_TXT, 414);
					healer->addNameReplacement(text, false);
					destStack->addNameReplacement(text, false);
					text.addReplacement(toHeal);
					pack.battleLog.push_back(text);

					UnitChanges info(state->unitId(), UnitChanges::EOperation::RESET_STATE);
					info.healthDelta = toHeal;
					state->save(info.data);
					pack.changedStacks.push_back(info);
					sendAndApply(&pack);
				}
			}
			break;
		}
		case EActionType::DAEMON_SUMMONING:
			//TODO: From Strategija:
			//Summon Demon is a level 2 spell.
		{
			if(target.size() < 1)
			{
				complain("Destination required for summon action.");
				ok = false;
				break;
			}

			const CStack * summoner = gs->curB->battleGetStackByID(ba.stackNumber);
			const CStack * destStack = gs->curB->battleGetStackByPos(target.at(0).hexValue, false);

			CreatureID summonedType(summoner->getBonusLocalFirst(Selector::type(Bonus::DAEMON_SUMMONING))->subtype);//in case summoner can summon more than one type of monsters... scream!

			ui64 risedHp = summoner->getCount() * summoner->valOfBonuses(Bonus::DAEMON_SUMMONING, summonedType.toEnum());
			ui64 targetHealth = destStack->getCreature()->MaxHealth() * destStack->baseAmount;

			ui64 canRiseHp = std::min(targetHealth, risedHp);
			ui32 canRiseAmount = canRiseHp / summonedType.toCreature()->MaxHealth();

			battle::UnitInfo info;
			info.id = gs->curB->battleNextUnitId();
			info.count = std::min(canRiseAmount, destStack->baseAmount);
			info.type = summonedType;
			info.side = summoner->side;
			info.position = gs->curB->getAvaliableHex(summonedType, summoner->side, destStack->getPosition());
			info.summoned = false;

			BattleUnitsChanged addUnits;
			addUnits.changedStacks.emplace_back(info.id, UnitChanges::EOperation::ADD);
			info.save(addUnits.changedStacks.back().data);

			if(info.count > 0) //there's rare possibility single creature cannot rise desired type
			{
				auto wrapper = wrapAction(ba);

				BattleUnitsChanged removeUnits;
				removeUnits.changedStacks.emplace_back(destStack->unitId(), UnitChanges::EOperation::REMOVE);
				sendAndApply(&removeUnits);
				sendAndApply(&addUnits);

				BattleSetStackProperty ssp;
				ssp.stackID = ba.stackNumber;
				ssp.which = BattleSetStackProperty::CASTS; //reduce number of casts
				ssp.val = -1;
				ssp.absolute = false;
				sendAndApply(&ssp);
			}
			break;
		}
		case EActionType::MONSTER_SPELL:
		{
			auto wrapper = wrapAction(ba);

			const CStack * stack = gs->curB->battleGetStackByID(ba.stackNumber);
			SpellID spellID = SpellID(ba.actionSubtype);

			const std::shared_ptr<Bonus> randSpellcaster = stack->getBonusLocalFirst(Selector::type(Bonus::RANDOM_SPELLCASTER));
			const std::shared_ptr<Bonus> spellcaster = stack->getBonusLocalFirst(Selector::typeSubtype(Bonus::SPELLCASTER, spellID));

			//TODO special bonus for genies ability
			if (randSpellcaster && battleGetRandomStackSpell(getRandomGenerator(), stack, CBattleInfoCallback::RANDOM_AIMED) < 0)
				spellID = battleGetRandomStackSpell(getRandomGenerator(), stack, CBattleInfoCallback::RANDOM_GENIE);

			if (spellID < 0)
				complain("That stack can't cast spells!");
			else
			{
				const CSpell * spell = SpellID(spellID).toSpell();
				spells::BattleCast parameters(gs->curB, stack, spells::Mode::CREATURE_ACTIVE, spell);
				int32_t spellLvl = 0;
				if(spellcaster)
					vstd::amax(spellLvl, spellcaster->val);
				if(randSpellcaster)
					vstd::amax(spellLvl, randSpellcaster->val);
				parameters.setSpellLevel(spellLvl);

				parameters.target = target;
				parameters.cast(spellEnv);
			}
			break;
		}
	}
	if(ba.actionType == EActionType::DAEMON_SUMMONING || ba.actionType == EActionType::WAIT || ba.actionType == EActionType::DEFEND
			|| ba.actionType == EActionType::SHOOT || ba.actionType == EActionType::MONSTER_SPELL)
		handleDamageFromObstacle(stack);
	if(ba.stackNumber == gs->curB->activeStack || battleResult.get()) //active stack has moved or battle has finished
		battleMadeAction.setn(true);
	return ok;
}

void CGameHandler::playerMessage(PlayerColor player, const std::string &message, ObjectInstanceID currObj)
{
	bool cheated = true;
	PlayerMessageClient temp_message(player, message);
	sendAndApply(&temp_message);

	std::vector<std::string> cheat;
	boost::split(cheat, message, boost::is_any_of(" "));
	int obj = 0;
	if (cheat.size() == 2)
	{
		obj = std::atoi(cheat[1].c_str());
		if (obj)
			currObj = ObjectInstanceID(obj);
	}

	const CGHeroInstance * hero = getHero(currObj);
	const CGTownInstance * town = getTown(currObj);
	if (!town && hero)
		town = hero->visitedTown;

	if (cheat.size() == 1 || obj)
		handleCheatCode(cheat[0], player, hero, town, cheated);
	else
	{
		for (const auto & i : gs->players)
		{
			if (i.first == PlayerColor::NEUTRAL)
				continue;
			if (cheat[1] == "ai")
			{
				if (i.second.human)
					continue;
			}
			else if (cheat[1] != "all" && cheat[1] != i.first.getStr())
				continue;

			if (cheat[0] == "vcmiformenos" || cheat[0] == "vcmieagles" || cheat[0] == "vcmiungoliant")
			{
				handleCheatCode(cheat[0], i.first, nullptr, nullptr, cheated);
			}
			else if (cheat[0] == "vcmiarmenelos")
			{
				for (const auto & t : i.second.towns)
				{
					handleCheatCode(cheat[0], i.first, nullptr, t, cheated);
				}
			}
			else
			{
				for (const auto & h : i.second.heroes)
				{
					handleCheatCode(cheat[0], i.first, h, nullptr, cheated);
				}
			}
		}
	}

	if (cheated)
	{
		SystemMessage temp_message(VLC->generaltexth->allTexts.at(260));
		sendAndApply(&temp_message);

		if(!player.isSpectator())
			checkVictoryLossConditionsForPlayer(player);//Player enter win code or got required art\creature
	}
}

bool CGameHandler::makeCustomAction(BattleAction & ba)
{
	switch(ba.actionType)
	{
	case EActionType::HERO_SPELL:
		{
			COMPLAIN_RET_FALSE_IF(ba.side > 1, "Side must be 0 or 1!");

			const CGHeroInstance *h = gs->curB->battleGetFightingHero(ba.side);
			COMPLAIN_RET_FALSE_IF((!h), "Wrong caster!");

			const CSpell * s = SpellID(ba.actionSubtype).toSpell();
			if (!s)
			{
				logGlobal->error("Wrong spell id (%d)!", ba.actionSubtype);
				return false;
			}

			spells::BattleCast parameters(gs->curB, h, spells::Mode::HERO, s);
			parameters.target = ba.getTarget(gs->curB);

			spells::detail::ProblemImpl problem;
			if(!s->canBeCast(problem, gs->curB, spells::Mode::HERO, h))//todo: should we check aimed cast?
			{
				logGlobal->warn("Spell cannot be cast!");
				std::vector<std::string> texts;
				problem.getAll(texts);
				for(auto s : texts)
					logGlobal->warn(s);
				return false;
			}

			StartAction start_action(ba);
			sendAndApply(&start_action); //start spell casting

			parameters.cast(spellEnv);

			sendAndApply(&end_action);
			if (!gs->curB->battleGetStackByID(gs->curB->activeStack))
			{
				battleMadeAction.setn(true);
			}
			checkBattleStateChanges();
			if (battleResult.get())
			{
				battleMadeAction.setn(true);
				//battle will be ended by startBattle function
				//endBattle(gs->curB->tile, gs->curB->heroes[0], gs->curB->heroes[1]);
			}

			return true;

		}
	}
	return false;
}

void CGameHandler::stackEnchantedTrigger(const CStack * st)
{
	auto bl = *(st->getBonuses(Selector::type(Bonus::ENCHANTED)));
	for(auto b : bl)
	{
		const CSpell * sp = SpellID(b->subtype).toSpell();
		if(!sp)
			continue;

		const int32_t val = bl.valOfBonuses(Selector::typeSubtype(b->type, b->subtype));
		const int32_t level = ((val > 3) ? (val - 3) : val);

		spells::BattleCast battleCast(gs->curB, st, spells::Mode::PASSIVE, sp);
		//this makes effect accumulate for at most 50 turns by default, but effect may be permanent and last till the end of battle
		battleCast.setEffectDuration(50);
		battleCast.setSpellLevel(level);

		if(val > 3)
		{
			for(auto s : gs->curB->battleGetAllStacks())
				if(battleMatchOwner(st, s, true) && s->isValidTarget()) //all allied
					battleCast.aimToUnit(s);
		}
		else
		{
			battleCast.aimToUnit(st);
		}
		battleCast.applyEffects(spellEnv, false, true);
	}
}

void CGameHandler::stackTurnTrigger(const CStack *st)
{
	BattleTriggerEffect bte;
	bte.stackID = st->ID;
	bte.effect = -1;
	bte.val = 0;
	bte.additionalInfo = 0;
	if (st->alive())
	{
		//unbind
		if (st->hasBonus(Selector::type(Bonus::BIND_EFFECT)))
		{
			bool unbind = true;
			BonusList bl = *(st->getBonuses(Selector::type(Bonus::BIND_EFFECT)));
			auto adjacent = gs->curB->battleAdjacentUnits(st);

			for (auto b : bl)
			{
				if(b->additionalInfo != CAddInfo::NONE)
				{
					const CStack * stack = gs->curB->battleGetStackByID(b->additionalInfo[0]); //binding stack must be alive and adjacent
					if(stack)
					{
						if(vstd::contains(adjacent, stack)) //binding stack is still present
							unbind = false;
					}
				}
				else
				{
					unbind = false;
				}
			}
			if (unbind)
			{
				BattleSetStackProperty ssp;
				ssp.which = BattleSetStackProperty::UNBIND;
				ssp.stackID = st->ID;
				sendAndApply(&ssp);
			}
		}
		//regeneration
		if (st->hasBonusOfType(Bonus::HP_REGENERATION))
		{
			bte.effect = Bonus::HP_REGENERATION;
			bte.val = std::min((int)(st->MaxHealth() - st->getFirstHPleft()), st->valOfBonuses(Bonus::HP_REGENERATION));
		}
		if (st->hasBonusOfType(Bonus::FULL_HP_REGENERATION))
		{
			bte.effect = Bonus::HP_REGENERATION;
			bte.val = st->MaxHealth() - st->getFirstHPleft();
		}
		if (bte.val) //anything to heal
			sendAndApply(&bte);

		if (st->hasBonusOfType(Bonus::POISON))
		{
			const std::shared_ptr<Bonus> b = st->getBonusLocalFirst(Selector::source(Bonus::SPELL_EFFECT, SpellID::POISON).And(Selector::type(Bonus::STACK_HEALTH)));
			if (b) //TODO: what if not?...
			{
				bte.val = std::max (b->val - 10, -(st->valOfBonuses(Bonus::POISON)));
				if (bte.val < b->val) //(negative) poison effect increases - update it
				{
					bte.effect = Bonus::POISON;
					sendAndApply(&bte);
				}
			}
		}
		if(st->hasBonusOfType(Bonus::MANA_DRAIN) && !st->drainedMana)
		{
			const PlayerColor opponent = gs->curB->otherPlayer(gs->curB->battleGetOwner(st));
			const CGHeroInstance * opponentHero = gs->curB->getHero(opponent);
			if(opponentHero)
			{
				ui32 manaDrained = st->valOfBonuses(Bonus::MANA_DRAIN);
				vstd::amin(manaDrained, opponentHero->mana);
				if(manaDrained)
				{
					bte.effect = Bonus::MANA_DRAIN;
					bte.val = manaDrained;
					bte.additionalInfo = opponentHero->id.getNum(); //for sanity
					sendAndApply(&bte);
				}
			}
		}
		if (st->isLiving() && !st->hasBonusOfType(Bonus::FEARLESS))
		{
			bool fearsomeCreature = false;
			for (CStack * stack : gs->curB->stacks)
			{
				if (battleMatchOwner(st, stack) && stack->alive() && stack->hasBonusOfType(Bonus::FEAR))
				{
					fearsomeCreature = true;
					break;
				}
			}
			if (fearsomeCreature)
			{
				if (getRandomGenerator().nextInt(99) < 10) //fixed 10%
				{
					bte.effect = Bonus::FEAR;
					sendAndApply(&bte);
				}
			}
		}
		BonusList bl = *(st->getBonuses(Selector::type(Bonus::ENCHANTER)));
		int side = gs->curB->whatSide(st->owner);
		if(st->canCast() && gs->curB->battleGetEnchanterCounter(side) == 0)
		{
			bool cast = false;
			while(!bl.empty() && !cast)
			{
				auto bonus = *RandomGeneratorUtil::nextItem(bl, getRandomGenerator());
				auto spellID = SpellID(bonus->subtype);
				const CSpell * spell = SpellID(spellID).toSpell();
				bl.remove_if([&bonus](const Bonus * b)
				{
					return b == bonus.get();
				});
				spells::BattleCast parameters(gs->curB, st, spells::Mode::ENCHANTER, spell);
				parameters.setSpellLevel(bonus->val);
				parameters.massive = true;
				parameters.smart = true;
				//todo: recheck effect level
				if(parameters.castIfPossible(spellEnv))
				{
					cast = true;

					int cooldown = bonus->additionalInfo[0];
					BattleSetStackProperty ssp;
					ssp.which = BattleSetStackProperty::ENCHANTER_COUNTER;
					ssp.absolute = false;
					ssp.val = cooldown;
					ssp.stackID = st->unitId();
					sendAndApply(&ssp);
				}
			}
		}
	}
}

bool CGameHandler::handleDamageFromObstacle(const CStack * curStack, bool stackIsMoving)
{
	if(!curStack->alive())
		return false;
	bool containDamageFromMoat = false;
	bool movementStoped = false;
	for(auto & obstacle : getAllAffectedObstaclesByStack(curStack))
	{
		if(obstacle->obstacleType == CObstacleInstance::SPELL_CREATED)
		{
			//helper info
			const SpellCreatedObstacle * spellObstacle = dynamic_cast<const SpellCreatedObstacle *>(obstacle.get());
			const ui8 side = curStack->side;

			if(!spellObstacle)
				COMPLAIN_RET("Invalid obstacle instance");

			if(spellObstacle->trigger)
			{
				const bool oneTimeObstacle = spellObstacle->removeOnTrigger;

				//hidden obstacle triggers effects until revealed
				if(!(spellObstacle->hidden && gs->curB->battleIsObstacleVisibleForSide(*obstacle, (BattlePerspective::BattlePerspective)side)))
				{
					const CGHeroInstance * hero = gs->curB->battleGetFightingHero(spellObstacle->casterSide);
					spells::ObstacleCasterProxy caster(gs->curB->sides.at(spellObstacle->casterSide).color, hero, spellObstacle);

					const CSpell * sp = SpellID(spellObstacle->ID).toSpell();
					if(!sp)
						COMPLAIN_RET("Invalid obstacle instance");

					spells::BattleCast battleCast(gs->curB, &caster, spells::Mode::HERO, sp);
					battleCast.aimToUnit(curStack);
					battleCast.applyEffects(spellEnv, true);

					if(oneTimeObstacle)
						removeObstacle(*obstacle);
				}
			}
		}
		else if(obstacle->obstacleType == CObstacleInstance::MOAT)
		{
			auto town = gs->curB->town;
			int damage = (town == nullptr) ? 0 : town->town->moatDamage;
			if(!containDamageFromMoat)
			{
				containDamageFromMoat = true;

				BattleStackAttacked bsa;
				bsa.damageAmount = damage;
				bsa.stackAttacked = curStack->ID;
				bsa.attackerID = -1;
				curStack->prepareAttacked(bsa, getRandomGenerator());

				StacksInjured si;
				si.stacks.push_back(bsa);
				sendAndApply(&si);
			}
		}

		if(!curStack->alive())
			return false;

		if((obstacle->stopsMovement() && stackIsMoving))
			movementStoped = true;
	}

	if(stackIsMoving)
		return curStack->alive() && !movementStoped;
	else
		return curStack->alive();
}

void CGameHandler::handleTimeEvents()
{
	gs->map->events.sort(evntCmp);
	while(gs->map->events.size() && gs->map->events.front().firstOccurence+1 == gs->day)
	{
		CMapEvent ev = gs->map->events.front();

		for (int player = 0; player < PlayerColor::PLAYER_LIMIT_I; player++)
		{
			auto color = PlayerColor(player);

			const PlayerState * pinfo = getPlayer(color, false); //do not output error if player does not exist

			if (pinfo  //player exists
				&& (ev.players & 1<<player) //event is enabled to this player
				&& ((ev.computerAffected && !pinfo->human)
					|| (ev.humanAffected && pinfo->human)
				)
			)
			{
				//give resources
				giveResources(color, ev.resources);

				//prepare dialog
				InfoWindow iw;
				iw.player = color;
				iw.text << ev.message;

				for (int i=0; i<ev.resources.size(); i++)
				{
					if (ev.resources.at(i)) //if resource is changed, we add it to the dialog
						iw.components.push_back(Component(Component::RESOURCE,i,ev.resources.at(i),0));
				}

				sendAndApply(&iw); //show dialog
			}
		} //PLAYERS LOOP

		if (ev.nextOccurence)
		{
			gs->map->events.pop_front();

			ev.firstOccurence += ev.nextOccurence;
			auto it = gs->map->events.begin();
			while(it != gs->map->events.end() && it->earlierThanOrEqual(ev))
				it++;
			gs->map->events.insert(it, ev);
		}
		else
		{
			gs->map->events.pop_front();
		}
	}

	//TODO send only if changed
	UpdateMapEvents ume;
	ume.events = gs->map->events;
	sendAndApply(&ume);
}

void CGameHandler::handleTownEvents(CGTownInstance * town, NewTurn &n)
{
	town->events.sort(evntCmp);
	while(town->events.size() && town->events.front().firstOccurence == gs->day)
	{
		PlayerColor player = town->tempOwner;
		CCastleEvent ev = town->events.front();
		const PlayerState * pinfo = getPlayer(player, false);

		if (pinfo  //player exists
			&& (ev.players & 1<<player.getNum()) //event is enabled to this player
			&& ((ev.computerAffected && !pinfo->human)
				|| (ev.humanAffected && pinfo->human)))
		{


			// dialog
			InfoWindow iw;
			iw.player = player;
			iw.text << ev.message;

			if (ev.resources.nonZero())
			{
				TResources was = n.res[player];
				n.res[player] += ev.resources;
				n.res[player].amax(0);

				for (int i=0; i<ev.resources.size(); i++)
					if (ev.resources.at(i) && pinfo->resources.at(i) != n.res.at(player).at(i)) //if resource had changed, we add it to the dialog
						iw.components.push_back(Component(Component::RESOURCE,i,n.res.at(player).at(i)-was.at(i),0));

			}

			for (auto & i : ev.buildings)
			{
				if (!town->hasBuilt(i))
				{
					buildStructure(town->id, i, true);
					iw.components.push_back(Component(Component::BUILDING, town->subID, i, 0));
				}
			}

			if (!ev.creatures.empty() && !vstd::contains(n.cres, town->id))
			{
				n.cres[town->id].tid = town->id;
				n.cres[town->id].creatures = town->creatures;
			}
			auto & sac = n.cres[town->id];

			for (si32 i=0;i<ev.creatures.size();i++) //creature growths
			{
				if (!town->creatures.at(i).second.empty() && ev.creatures.at(i) > 0)//there is dwelling
				{
					sac.creatures[i].first += ev.creatures.at(i);
					iw.components.push_back(Component(Component::CREATURE,
							town->creatures.at(i).second.back(), ev.creatures.at(i), 0));
				}
			}
			sendAndApply(&iw); //show dialog
		}

		if (ev.nextOccurence)
		{
			town->events.pop_front();

			ev.firstOccurence += ev.nextOccurence;
			auto it = town->events.begin();
			while(it != town->events.end() && it->earlierThanOrEqual(ev))
				it++;
			town->events.insert(it, ev);
		}
		else
		{
			town->events.pop_front();
		}
	}

	//TODO send only if changed
	UpdateCastleEvents uce;
	uce.town = town->id;
	uce.events = town->events;
	sendAndApply(&uce);
}

bool CGameHandler::complain(const std::string &problem)
{
	sendMessageToAll("Server encountered a problem: " + problem);
	logGlobal->error(problem);
	return true;
}

void CGameHandler::showGarrisonDialog(ObjectInstanceID upobj, ObjectInstanceID hid, bool removableUnits)
{
	//PlayerColor player = getOwner(hid);
	auto upperArmy = dynamic_cast<const CArmedInstance*>(getObj(upobj));
	auto lowerArmy = dynamic_cast<const CArmedInstance*>(getObj(hid));

	assert(lowerArmy);
	assert(upperArmy);

	auto garrisonQuery = std::make_shared<CGarrisonDialogQuery>(this, upperArmy, lowerArmy);
	queries.addQuery(garrisonQuery);

	GarrisonDialog gd;
	gd.hid = hid;
	gd.objid = upobj;
	gd.removableUnits = removableUnits;
	gd.queryID = garrisonQuery->queryID;
	sendAndApply(&gd);
}

void CGameHandler::showThievesGuildWindow(PlayerColor player, ObjectInstanceID requestingObjId)
{
	OpenWindow ow;
	ow.window = OpenWindow::THIEVES_GUILD;
	ow.id1 = player.getNum();
	ow.id2 = requestingObjId.getNum();
	sendAndApply(&ow);
}

bool CGameHandler::isAllowedExchange(ObjectInstanceID id1, ObjectInstanceID id2)
{
	if (id1 == id2)
		return true;

	const CGObjectInstance *o1 = getObj(id1), *o2 = getObj(id2);
	if (!o1 || !o2)
		return true; //arranging stacks within an object should be always allowed

	if (o1 && o2)
	{
		if (o1->ID == Obj::TOWN)
		{
			const CGTownInstance *t = static_cast<const CGTownInstance*>(o1);
			if (t->visitingHero == o2  ||  t->garrisonHero == o2)
				return true;
		}
		if (o2->ID == Obj::TOWN)
		{
			const CGTownInstance *t = static_cast<const CGTownInstance*>(o2);
			if (t->visitingHero == o1  ||  t->garrisonHero == o1)
				return true;
		}

		if (o1->ID == Obj::HERO && o2->ID == Obj::HERO)
		{
			const CGHeroInstance *h1 = static_cast<const CGHeroInstance*>(o1);
			const CGHeroInstance *h2 = static_cast<const CGHeroInstance*>(o2);

			// two heroes in same town (garrisoned and visiting)
			if (h1->visitedTown != nullptr && h2->visitedTown != nullptr && h1->visitedTown == h2->visitedTown)
				return true;
		}

		//Ongoing garrison exchange
		if (auto dialog = std::dynamic_pointer_cast<CGarrisonDialogQuery>(queries.topQuery(o1->tempOwner)))
		{
			if (dialog->exchangingArmies.at(0) == o1 && dialog->exchangingArmies.at(1) == o2)
				return true;

			if (dialog->exchangingArmies.at(1) == o1 && dialog->exchangingArmies.at(0) == o2)
				return true;
		}
	}

	return false;
}

void CGameHandler::objectVisited(const CGObjectInstance * obj, const CGHeroInstance * h)
{
	logGlobal->debug("%s visits %s (%d:%d)", h->nodeName(), obj->getObjectName(), obj->ID, obj->subID);
	auto visitQuery = std::make_shared<CObjectVisitQuery>(this, obj, h, obj->visitablePos());
	queries.addQuery(visitQuery); //TODO real visit pos

	HeroVisit hv;
	hv.objId = obj->id;
	hv.heroId = h->id;
	hv.player = h->tempOwner;
	hv.starting = true;
	sendAndApply(&hv);

	obj->onHeroVisit(h);

	queries.popIfTop(visitQuery); //visit ends here if no queries were created
}

void CGameHandler::objectVisitEnded(const CObjectVisitQuery &query)
{
	logGlobal->debug("%s visit ends.\n", query.visitingHero->nodeName());

	HeroVisit hv;
	hv.player = query.players.front();
	hv.heroId = query.visitingHero->id;
	hv.starting = false;
	sendAndApply(&hv);
}

bool CGameHandler::buildBoat(ObjectInstanceID objid)
{
	const IShipyard *obj = IShipyard::castFrom(getObj(objid));

	if (obj->shipyardStatus() != IBoatGenerator::GOOD)
	{
		complain("Cannot build boat in this shipyard!");
		return false;
	}
	else if (obj->o->ID == Obj::TOWN
	        && !static_cast<const CGTownInstance*>(obj)->hasBuilt(BuildingID::SHIPYARD))
	{
		complain("Cannot build boat in the town - no shipyard!");
		return false;
	}

	const PlayerColor playerID = obj->o->tempOwner;
	TResources boatCost;
	obj->getBoatCost(boatCost);
	TResources aviable = getPlayer(playerID)->resources;

	if (!aviable.canAfford(boatCost))
	{
		complain("Not enough resources to build a boat!");
		return false;
	}

	int3 tile = obj->bestLocation();
	if (!gs->map->isInTheMap(tile))
	{
		complain("Cannot find appropriate tile for a boat!");
		return false;
	}

	//take boat cost
	giveResources(playerID, -boatCost);

	//create boat
	NewObject no;
	no.ID = Obj::BOAT;
	no.subID = obj->getBoatType();
	no.pos = tile + int3(1,0,0);
	sendAndApply(&no);

	return true;
}

void CGameHandler::engageIntoBattle(PlayerColor player)
{
	//notify interfaces
	PlayerBlocked pb;
	pb.player = player;
	pb.reason = PlayerBlocked::UPCOMING_BATTLE;
	pb.startOrEnd = PlayerBlocked::BLOCKADE_STARTED;
	sendAndApply(&pb);
}

void CGameHandler::checkVictoryLossConditions(const std::set<PlayerColor> & playerColors)
{
	for (auto playerColor : playerColors)
	{
		if (getPlayer(playerColor, false))
			checkVictoryLossConditionsForPlayer(playerColor);
	}
}

void CGameHandler::checkVictoryLossConditionsForAll()
{
	std::set<PlayerColor> playerColors;
	for (int i = 0; i < PlayerColor::PLAYER_LIMIT_I; ++i)
	{
		playerColors.insert(PlayerColor(i));
	}
	checkVictoryLossConditions(playerColors);
}

void CGameHandler::checkVictoryLossConditionsForPlayer(PlayerColor player)
{
	const PlayerState * p = getPlayer(player);
	if (p->status != EPlayerStatus::INGAME) return;

	auto victoryLossCheckResult = gs->checkForVictoryAndLoss(player);

	if (victoryLossCheckResult.victory() || victoryLossCheckResult.loss())
	{
		InfoWindow iw;
		getVictoryLossMessage(player, victoryLossCheckResult, iw);
		sendAndApply(&iw);

		PlayerEndsGame peg;
		peg.player = player;
		peg.victoryLossCheckResult = victoryLossCheckResult;
		sendAndApply(&peg);

		if (victoryLossCheckResult.victory())
		{
			//one player won -> all enemies lost
			for (auto i = gs->players.cbegin(); i!=gs->players.cend(); i++)
			{
				if (i->first != player && getPlayer(i->first)->status == EPlayerStatus::INGAME)
				{
					peg.player = i->first;
					peg.victoryLossCheckResult = getPlayerRelations(player, i->first) == PlayerRelations::ALLIES ?
								victoryLossCheckResult : victoryLossCheckResult.invert(); // ally of winner

					InfoWindow iw;
					getVictoryLossMessage(player, peg.victoryLossCheckResult, iw);
					iw.player = i->first;

					sendAndApply(&iw);
					sendAndApply(&peg);
				}
			}

			if(p->human)
			{
				lobby->state = EServerState::GAMEPLAY_ENDED;
			}
		}
		else
		{
			//copy heroes vector to avoid iterator invalidation as removal change PlayerState
			auto hlp = p->heroes;
			for (auto h : hlp) //eliminate heroes
			{
				if (h.get())
					removeObject(h);
			}

			//player lost -> all his objects become unflagged (neutral)
			for (auto obj : gs->map->objects) //unflag objs
			{
				if (obj.get() && obj->tempOwner == player)
					setOwner(obj, PlayerColor::NEUTRAL);
			}

			//eliminating one player may cause victory of another:
			std::set<PlayerColor> playerColors;

			//do not copy player state (CBonusSystemNode) by value
			for (auto &p : gs->players) //players may have different colors, iterate over players and not integers
			{
				if (p.first != player)
					playerColors.insert(p.first);
			}

			//notify all players
			for (auto pc : playerColors)
			{
				if (getPlayer(pc)->status == EPlayerStatus::INGAME)
				{
					InfoWindow iw;
					getVictoryLossMessage(player, victoryLossCheckResult.invert(), iw);
					iw.player = pc;
					sendAndApply(&iw);
				}
			}
			checkVictoryLossConditions(playerColors);
		}

		auto playerInfo = getPlayer(gs->currentPlayer, false);
		// If we are called before the actual game start, there might be no current player
		if (playerInfo && playerInfo->status != EPlayerStatus::INGAME)
		{
			// If player making turn has lost his turn must be over as well
			states.setFlag(gs->currentPlayer, &PlayerStatus::makingTurn, false);
		}
	}
}

void CGameHandler::getVictoryLossMessage(PlayerColor player, const EVictoryLossCheckResult & victoryLossCheckResult, InfoWindow & out) const
{
	out.player = player;
	out.text.clear();
	out.text << victoryLossCheckResult.messageToSelf;
	// hackish, insert one player-specific string, if applicable
	if (victoryLossCheckResult.messageToSelf.find("%s") != std::string::npos)
		out.text.addReplacement(MetaString::COLOR, player.getNum());

	out.components.push_back(Component(Component::FLAG, player.getNum(), 0, 0));
}

bool CGameHandler::dig(const CGHeroInstance *h)
{
	for (auto i = gs->map->objects.cbegin(); i != gs->map->objects.cend(); i++) //unflag objs
	{
		if (*i && (*i)->ID == Obj::HOLE  &&  (*i)->pos == h->getPosition())
		{
			complain("Cannot dig - there is already a hole under the hero!");
			return false;
		}
	}

	if (h->diggingStatus() != EDiggingStatus::CAN_DIG) //checks for terrain and movement
		COMPLAIN_RETF("Hero cannot dig (error code %d)!", h->diggingStatus());

	//create a hole
	NewObject no;
	no.ID = Obj::HOLE;
	no.pos = h->getPosition();
	no.subID = 0;
	sendAndApply(&no);

	//take MPs
	SetMovePoints smp;
	smp.hid = h->id;
	smp.val = 0;
	sendAndApply(&smp);

	InfoWindow iw;
	iw.player = h->tempOwner;
	if (gs->map->grailPos == h->getPosition())
	{
		iw.text.addTxt(MetaString::GENERAL_TXT, 58); //"Congratulations! After spending many hours digging here, your hero has uncovered the "
		iw.text.addTxt(MetaString::ART_NAMES, ArtifactID::GRAIL);
		iw.soundID = soundBase::ULTIMATEARTIFACT;
		giveHeroNewArtifact(h, VLC->arth->artifacts[ArtifactID::GRAIL], ArtifactPosition::PRE_FIRST); //give grail
		sendAndApply(&iw);

		iw.soundID = soundBase::invalid;
		iw.text.clear();
		iw.text.addTxt(MetaString::ART_DESCR, ArtifactID::GRAIL);
		sendAndApply(&iw);
	}
	else
	{
		iw.text.addTxt(MetaString::GENERAL_TXT, 59); //"Nothing here. \n Where could it be?"
		iw.soundID = soundBase::Dig;
		sendAndApply(&iw);
	}

	return true;
}

void CGameHandler::attackCasting(bool ranged, Bonus::BonusType attackMode, const battle::Unit * attacker, const battle::Unit * defender)
{
	if(attacker->hasBonusOfType(attackMode))
	{
		std::set<SpellID> spellsToCast;
		TBonusListPtr spells = attacker->getBonuses(Selector::type(attackMode));
		for(const std::shared_ptr<Bonus> sf : *spells)
		{
			spellsToCast.insert(SpellID(sf->subtype));
		}
		for(SpellID spellID : spellsToCast)
		{
			bool castMe = false;
			if(!defender->alive())
			{
				logGlobal->debug("attackCasting: all attacked creatures have been killed");
				return;
			}
			int32_t spellLevel = 0;
			TBonusListPtr spellsByType = attacker->getBonuses(Selector::typeSubtype(attackMode, spellID));
			for(const std::shared_ptr<Bonus> sf : *spellsByType)
			{
				int meleeRanged;
				if(sf->additionalInfo.size() < 2)
				{
					// legacy format
					vstd::amax(spellLevel, sf->additionalInfo[0] % 1000);
					meleeRanged = sf->additionalInfo[0] / 1000;
				}
				else
				{
					vstd::amax(spellLevel, sf->additionalInfo[0]);
					meleeRanged = sf->additionalInfo[1];
				}
				if (meleeRanged == 0 || (meleeRanged == 1 && ranged) || (meleeRanged == 2 && !ranged))
					castMe = true;
			}
			int chance = attacker->valOfBonuses((Selector::typeSubtype(attackMode, spellID)));
			vstd::amin(chance, 100);

			const CSpell * spell = SpellID(spellID).toSpell();
			spells::AbilityCaster caster(attacker, spellLevel);

			if(!spell->canBeCastAt(gs->curB, spells::Mode::PASSIVE, &caster, defender->getPosition()))
				continue;

			//check if spell should be cast (probability handling)
			if(getRandomGenerator().nextInt(99) >= chance)
				continue;

			//casting
			if(castMe)
			{
				spells::BattleCast parameters(gs->curB, &caster, spells::Mode::PASSIVE, spell);
				parameters.aimToUnit(defender);
				parameters.cast(spellEnv);
			}
		}
	}
}

void CGameHandler::handleAttackBeforeCasting(bool ranged, const CStack * attacker, const CStack * defender)
{
	attackCasting(ranged, Bonus::SPELL_BEFORE_ATTACK, attacker, defender); //no death stare / acid breath needed?
}

void CGameHandler::handleAfterAttackCasting(bool ranged, const CStack * attacker, const CStack * defender)
{
	if(!attacker->alive() || !defender->alive()) // can be already dead
		return;

	attackCasting(ranged, Bonus::SPELL_AFTER_ATTACK, attacker, defender);

	if(!defender->alive())
	{
		//don't try death stare or acid breath on dead stack (crash!)
		return;
	}

	if(attacker->hasBonusOfType(Bonus::DEATH_STARE))
	{
		// mechanics of Death Stare as in H3:
		// each gorgon have 10% chance to kill (counted separately in H3) -> binomial distribution
		//original formula x = min(x, (gorgons_count + 9)/10);

		double chanceToKill = attacker->valOfBonuses(Bonus::DEATH_STARE, 0) / 100.0f;
		vstd::amin(chanceToKill, 1); //cap at 100%

		std::binomial_distribution<> distribution(attacker->getCount(), chanceToKill);

		int staredCreatures = distribution(getRandomGenerator().getStdGenerator());

		double cap = 1 / std::max(chanceToKill, (double)(0.01));//don't divide by 0
		int maxToKill = (attacker->getCount() + cap - 1) / cap; //not much more than chance * count
		vstd::amin(staredCreatures, maxToKill);

		staredCreatures += (attacker->level() * attacker->valOfBonuses(Bonus::DEATH_STARE, 1)) / defender->level();
		if(staredCreatures)
		{
			//TODO: death stare was not originally available for multiple-hex attacks, but...
			const CSpell * spell = SpellID(SpellID::DEATH_STARE).toSpell();

			spells::AbilityCaster caster(attacker, 0);

			spells::BattleCast parameters(gs->curB, &caster, spells::Mode::PASSIVE, spell);
			parameters.aimToUnit(defender);
			parameters.setEffectValue(staredCreatures);
			parameters.cast(spellEnv);
		}
	}

	if(!defender->alive())
		return;

	int64_t acidDamage = 0;
	TBonusListPtr acidBreath = attacker->getBonuses(Selector::type(Bonus::ACID_BREATH));
	for(const std::shared_ptr<Bonus> b : *acidBreath)
	{
		if(b->additionalInfo[0] > getRandomGenerator().nextInt(99))
			acidDamage += b->val;
	}

	if(acidDamage > 0)
	{
		const CSpell * spell = SpellID(SpellID::ACID_BREATH_DAMAGE).toSpell();

		spells::AbilityCaster caster(attacker, 0);

		spells::BattleCast parameters(gs->curB, &caster, spells::Mode::PASSIVE, spell);
		parameters.aimToUnit(defender);
		parameters.setEffectValue(acidDamage * attacker->getCount());
		parameters.cast(spellEnv);
	}


	if(!defender->alive())
		return;

	if(attacker->hasBonusOfType(Bonus::TRANSMUTATION) && defender->isLiving()) //transmutation mechanics, similar to WoG werewolf ability
	{
		double chanceToTrigger = attacker->valOfBonuses(Bonus::TRANSMUTATION) / 100.0f;
		vstd::amin(chanceToTrigger, 1); //cap at 100%

		if(getRandomGenerator().getDoubleRange(0, 1)() > chanceToTrigger)
			return;

		int bonusAdditionalInfo = attacker->getBonus(Selector::type(Bonus::TRANSMUTATION))->additionalInfo[0];

		if(defender->getCreature()->idNumber == bonusAdditionalInfo ||
			(bonusAdditionalInfo == CAddInfo::NONE && defender->getCreature()->idNumber == attacker->getCreature()->idNumber))
			return;

		battle::UnitInfo resurrectInfo;
		resurrectInfo.id = gs->curB->battleNextUnitId();
		resurrectInfo.summoned = false;
		resurrectInfo.position = defender->getPosition();
		resurrectInfo.side = defender->unitSide();

		if(bonusAdditionalInfo != CAddInfo::NONE)
			resurrectInfo.type = CreatureID(bonusAdditionalInfo);
		else
			resurrectInfo.type = attacker->creatureId();

		if(attacker->hasBonusOfType((Bonus::TRANSMUTATION), 0))
			resurrectInfo.count = std::max((defender->getCount() * defender->MaxHealth()) / resurrectInfo.type.toCreature()->MaxHealth(), 1u);
		else if (attacker->hasBonusOfType((Bonus::TRANSMUTATION), 1))
			resurrectInfo.count = defender->getCount();
		else
			return; //wrong subtype

		BattleUnitsChanged addUnits;
		addUnits.changedStacks.emplace_back(resurrectInfo.id, UnitChanges::EOperation::ADD);
		resurrectInfo.save(addUnits.changedStacks.back().data);

		BattleUnitsChanged removeUnits;
		removeUnits.changedStacks.emplace_back(defender->unitId(), UnitChanges::EOperation::REMOVE);
		sendAndApply(&removeUnits);
		sendAndApply(&addUnits);
	}

	if(attacker->hasBonusOfType(Bonus::DESTRUCTION, 0) || attacker->hasBonusOfType(Bonus::DESTRUCTION, 1))
	{
		double chanceToTrigger = 0;
		int amountToDie = 0;

		if(attacker->hasBonusOfType(Bonus::DESTRUCTION, 0)) //killing by percentage
		{
			chanceToTrigger = attacker->valOfBonuses(Bonus::DESTRUCTION, 0) / 100.0f;
			int percentageToDie = attacker->getBonus(Selector::type(Bonus::DESTRUCTION).And(Selector::subtype(0)))->additionalInfo[0];
			amountToDie = defender->getCount() * percentageToDie * 0.01f;
		}
		else if(attacker->hasBonusOfType(Bonus::DESTRUCTION, 1)) //killing by count
		{
			chanceToTrigger = attacker->valOfBonuses(Bonus::DESTRUCTION, 1) / 100.0f;
			amountToDie = attacker->getBonus(Selector::type(Bonus::DESTRUCTION).And(Selector::subtype(1)))->additionalInfo[0];
		}

		vstd::amin(chanceToTrigger, 1); //cap trigger chance at 100%

		if(getRandomGenerator().getDoubleRange(0, 1)() > chanceToTrigger)
			return;

		BattleStackAttacked bsa;
		bsa.attackerID = -1;
		bsa.stackAttacked = defender->ID;
		bsa.damageAmount = amountToDie * defender->MaxHealth();
		bsa.flags = BattleStackAttacked::SPELL_EFFECT;
		bsa.spellID = SpellID::SLAYER;
		defender->prepareAttacked(bsa, getRandomGenerator());

		StacksInjured si;
		si.stacks.push_back(bsa);

		sendAndApply(&si);
	}
}

void CGameHandler::visitObjectOnTile(const TerrainTile &t, const CGHeroInstance * h)
{
	if (!t.visitableObjects.empty())
	{
		//to prevent self-visiting heroes on space press
		if (t.visitableObjects.back() != h)
			objectVisited(t.visitableObjects.back(), h);
		else if (t.visitableObjects.size() > 1)
			objectVisited(*(t.visitableObjects.end()-2),h);
	}
}

bool CGameHandler::sacrificeCreatures(const IMarket * market, const CGHeroInstance * hero, const std::vector<SlotID> & slot, const std::vector<ui32> & count)
{
	if (!hero)
		COMPLAIN_RET("You need hero to sacrifice creature!");

	int expSum = 0;
	auto finish = [this, &hero, &expSum]()
	{
		changePrimSkill(hero, PrimarySkill::EXPERIENCE, hero->calculateXp(expSum));
	};

	for(int i = 0; i < slot.size(); ++i)
	{
		int oldCount = hero->getStackCount(slot[i]);

		if(oldCount < count[i])
		{
			finish();
			COMPLAIN_RET("Not enough creatures to sacrifice!")
		}
		else if(oldCount == count[i] && hero->stacksCount() == 1 && hero->needsLastStack())
		{
			finish();
			COMPLAIN_RET("Cannot sacrifice last creature!");
		}

		int crid = hero->getStack(slot[i]).type->idNumber;

		changeStackCount(StackLocation(hero, slot[i]), -count[i]);

		int dump, exp;
		market->getOffer(crid, 0, dump, exp, EMarketMode::CREATURE_EXP);
		exp *= count[i];
		expSum += exp;
	}

	finish();

	return true;
}

bool CGameHandler::sacrificeArtifact(const IMarket * m, const CGHeroInstance * hero, const std::vector<ArtifactPosition> & slot)
{
	if (!hero)
		COMPLAIN_RET("You need hero to sacrifice artifact!");

	int expSum = 0;
	auto finish = [this, &hero, &expSum]()
	{
		changePrimSkill(hero, PrimarySkill::EXPERIENCE, hero->calculateXp(expSum));
	};

	for(int i = 0; i < slot.size(); ++i)
	{
		ArtifactLocation al(hero, slot[i]);
		const CArtifactInstance * a = al.getArt();

		if(!a)
		{
			finish();
			COMPLAIN_RET("Cannot find artifact to sacrifice!");
		}

		const CArtifactInstance * art = hero->getArt(slot[i]);

		if(!art)
		{
			finish();
			COMPLAIN_RET("No artifact at position to sacrifice!");
		}

		si32 typId = art->artType->id;
		int dmp, expToGive;

		m->getOffer(typId, 0, dmp, expToGive, EMarketMode::ARTIFACT_EXP);

		expSum += expToGive;

		removeArtifact(al);
	}

	finish();

	return true;
}

void CGameHandler::makeStackDoNothing(const CStack * next)
{
	BattleAction doNothing;
	doNothing.actionType = EActionType::NO_ACTION;
	doNothing.side = next->side;
	doNothing.stackNumber = next->ID;

	makeAutomaticAction(next, doNothing);
}

bool CGameHandler::insertNewStack(const StackLocation &sl, const CCreature *c, TQuantity count)
{
	if (sl.army->hasStackAtSlot(sl.slot))
		COMPLAIN_RET("Slot is already taken!");

	if (!sl.slot.validSlot())
		COMPLAIN_RET("Cannot insert stack to that slot!");

	InsertNewStack ins;
	ins.army = sl.army->id;
	ins.slot = sl.slot;
	ins.type = c->idNumber;
	ins.count = count;
	sendAndApply(&ins);
	return true;
}

bool CGameHandler::eraseStack(const StackLocation &sl, bool forceRemoval)
{
	if (!sl.army->hasStackAtSlot(sl.slot))
		COMPLAIN_RET("Cannot find a stack to erase");

	if (sl.army->stacksCount() == 1 //from the last stack
		&& sl.army->needsLastStack() //that must be left
		&& !forceRemoval) //ignore above conditions if we are forcing removal
	{
		COMPLAIN_RET("Cannot erase the last stack!");
	}

	EraseStack es;
	es.army = sl.army->id;
	es.slot = sl.slot;
	sendAndApply(&es);
	return true;
}

bool CGameHandler::changeStackCount(const StackLocation &sl, TQuantity count, bool absoluteValue)
{
	TQuantity currentCount = sl.army->getStackCount(sl.slot);
	if ((absoluteValue && count < 0)
		|| (!absoluteValue && -count > currentCount))
	{
		COMPLAIN_RET("Cannot take more stacks than present!");
	}

	if ((currentCount == -count  &&  !absoluteValue)
	   || (!count && absoluteValue))
	{
		eraseStack(sl);
	}
	else
	{
		ChangeStackCount csc;
		csc.army = sl.army->id;
		csc.slot = sl.slot;
		csc.count = count;
		csc.absoluteValue = absoluteValue;
		sendAndApply(&csc);
	}
	return true;
}

bool CGameHandler::addToSlot(const StackLocation &sl, const CCreature *c, TQuantity count)
{
	const CCreature *slotC = sl.army->getCreature(sl.slot);
	if (!slotC) //slot is empty
		insertNewStack(sl, c, count);
	else if (c == slotC)
		changeStackCount(sl, count);
	else
	{
		COMPLAIN_RET("Cannot add " + c->namePl + " to slot " + boost::lexical_cast<std::string>(sl.slot) + "!");
	}
	return true;
}

void CGameHandler::tryJoiningArmy(const CArmedInstance *src, const CArmedInstance *dst, bool removeObjWhenFinished, bool allowMerging)
{
	if (removeObjWhenFinished)
		removeAfterVisit(src);

	if (!src->canBeMergedWith(*dst, allowMerging))
	{
		if (allowMerging) //do that, add all matching creatures.
		{
			bool cont = true;
			while (cont)
			{
				for (auto i = src->stacks.begin(); i != src->stacks.end(); i++)//while there are unmoved creatures
				{
					SlotID pos = dst->getSlotFor(i->second->type);
					if (pos.validSlot())
					{
						moveStack(StackLocation(src, i->first), StackLocation(dst, pos));
						cont = true;
						break; //or iterator crashes
					}
					cont = false;
				}
			}
		}
		showGarrisonDialog(src->id, dst->id, true); //show garrison window and optionally remove ourselves from map when player ends
	}
	else //merge
	{
		moveArmy(src, dst, allowMerging);
	}
}

bool CGameHandler::moveStack(const StackLocation &src, const StackLocation &dst, TQuantity count)
{
	if (!src.army->hasStackAtSlot(src.slot))
		COMPLAIN_RET("No stack to move!");

	if (dst.army->hasStackAtSlot(dst.slot) && dst.army->getCreature(dst.slot) != src.army->getCreature(src.slot))
		COMPLAIN_RET("Cannot move: stack of different type at destination pos!");

	if (!dst.slot.validSlot())
		COMPLAIN_RET("Cannot move stack to that slot!");

	if (count == -1)
	{
		count = src.army->getStackCount(src.slot);
	}

	if (src.army != dst.army  //moving away
		&&  count == src.army->getStackCount(src.slot) //all creatures
		&& src.army->stacksCount() == 1 //from the last stack
		&& src.army->needsLastStack()) //that must be left
	{
		COMPLAIN_RET("Cannot move away the last creature!");
	}

	RebalanceStacks rs;
	rs.srcArmy = src.army->id;
	rs.dstArmy = dst.army->id;
	rs.srcSlot = src.slot;
	rs.dstSlot = dst.slot;
	rs.count = count;
	sendAndApply(&rs);
	return true;
}

bool CGameHandler::swapStacks(const StackLocation & sl1, const StackLocation & sl2)
{
	if(!sl1.army->hasStackAtSlot(sl1.slot))
	{
		return moveStack(sl2, sl1);
	}
	else if(!sl2.army->hasStackAtSlot(sl2.slot))
	{
		return moveStack(sl1, sl2);
	}
	else
	{
		SwapStacks ss;
		ss.srcArmy = sl1.army->id;
		ss.dstArmy = sl2.army->id;
		ss.srcSlot = sl1.slot;
		ss.dstSlot = sl2.slot;
		sendAndApply(&ss);
		return true;
	}
}

void CGameHandler::runBattle()
{
	setBattle(gs->curB);
	assert(gs->curB);
	//TODO: pre-tactic stuff, call scripts etc.

	//tactic round
	{
		while (gs->curB->tacticDistance && !battleResult.get())
			boost::this_thread::sleep(boost::posix_time::milliseconds(50));
	}

	//initial stacks appearance triggers, e.g. built-in bonus spells
	auto initialStacks = gs->curB->stacks; //use temporary variable to outclude summoned stacks added to gs->curB->stacks from processing

	for (CStack * stack : initialStacks)
	{
		if (stack->hasBonusOfType(Bonus::SUMMON_GUARDIANS))
		{
			const std::shared_ptr<Bonus> summonInfo = stack->getBonus(Selector::type(Bonus::SUMMON_GUARDIANS));
			auto accessibility = getAccesibility();
			CreatureID creatureData = CreatureID(summonInfo->subtype);
			std::vector<BattleHex> targetHexes;
			const bool targetIsBig = stack->getCreature()->isDoubleWide(); //target = creature to guard
			const bool guardianIsBig = creatureData.toCreature()->isDoubleWide();

			/*Chosen idea for two hex units was to cover all possible surrounding hexes of target unit with as small number of stacks as possible.
			For one-hex targets there are four guardians - front, back and one per side (up + down).
			Two-hex targets are wider and the difference is there are two guardians per side to cover 3 hexes + extra hex in the front
			Additionally, there are special cases for starting positions etc., where guardians would be outside of battlefield if spawned normally*/
			if (!guardianIsBig)
				targetHexes = stack->getSurroundingHexes();
			else
				summonGuardiansHelper(targetHexes, stack->getPosition(), stack->side, targetIsBig);

			for(auto hex : targetHexes)
			{
				if(accessibility.accessible(hex, guardianIsBig, stack->side)) //without this multiple creatures can occupy one hex
				{
					battle::UnitInfo info;
					info.id = gs->curB->battleNextUnitId();
					info.count =  std::max(1, (int)(stack->getCount() * 0.01 * summonInfo->val));
					info.type = creatureData;
					info.side = stack->side;
					info.position = hex;
					info.summoned = true;

					BattleUnitsChanged pack;
					pack.changedStacks.emplace_back(info.id, UnitChanges::EOperation::ADD);
					info.save(pack.changedStacks.back().data);
					sendAndApply(&pack);
				}
			}
		}

		stackEnchantedTrigger(stack);
	}

	//spells opening battle
	for (int i = 0; i < 2; ++i)
	{
		auto h = gs->curB->battleGetFightingHero(i);
		if (h)
		{
			TBonusListPtr bl = h->getBonuses(Selector::type(Bonus::OPENING_BATTLE_SPELL));

			for (auto b : *bl)
			{
				spells::BonusCaster caster(h, b);

				const CSpell * spell = SpellID(b->subtype).toSpell();

				spells::BattleCast parameters(gs->curB, &caster, spells::Mode::PASSIVE, spell);
				parameters.setSpellLevel(3);
				parameters.setEffectDuration(b->val);
				parameters.massive = true;
				parameters.castIfPossible(spellEnv);
			}
		}
	}

	bool firstRound = true;//FIXME: why first round is -1?

	//main loop
	while (!battleResult.get()) //till the end of the battle ;]
	{
		BattleNextRound bnr;
		bnr.round = gs->curB->round + 1;
		logGlobal->debug("Round %d", bnr.round);
		sendAndApply(&bnr);

		auto obstacles = gs->curB->obstacles; //we copy container, because we're going to modify it
		for (auto &obstPtr : obstacles)
		{
			if (const SpellCreatedObstacle *sco = dynamic_cast<const SpellCreatedObstacle *>(obstPtr.get()))
				if (sco->turnsRemaining == 0)
					removeObstacle(*obstPtr);
		}

		const BattleInfo & curB = *gs->curB;

		for(auto stack : curB.stacks)
		{
			if(stack->alive() && !firstRound)
				stackEnchantedTrigger(stack);
		}

		//stack loop

		auto getNextStack = [this]() -> const CStack *
		{
			if(battleResult.get())
				return nullptr;

			std::vector<battle::Units> q;
			gs->curB->battleGetTurnOrder(q, 1, 0, -1); //todo: get rid of "turn -1"

			if(!q.empty())
			{
				if(!q.front().empty())
				{
					auto next = q.front().front();
					if(next->willMove())
						return dynamic_cast<const CStack *>(next);
				}
			}

			return nullptr;
		};

		const CStack * next = nullptr;
		while((next = getNextStack()))
		{
			BattleUnitsChanged removeGhosts;
			for(auto stack : curB.stacks)
			{
				if(stack->ghostPending)
					removeGhosts.changedStacks.emplace_back(stack->unitId(), UnitChanges::EOperation::REMOVE);
			}

			if(!removeGhosts.changedStacks.empty())
				sendAndApply(&removeGhosts);

			//check for bad morale => freeze
			int nextStackMorale = next->MoraleVal();
			if (nextStackMorale < 0 &&
				!(NBonus::hasOfType(gs->curB->battleGetFightingHero(0), Bonus::BLOCK_MORALE)
				   || NBonus::hasOfType(gs->curB->battleGetFightingHero(1), Bonus::BLOCK_MORALE)) //checking if gs->curB->heroes have (or don't have) morale blocking bonuses)
				)
			{
				if (getRandomGenerator().nextInt(23) < -2 * nextStackMorale)
				{
					//unit loses its turn - empty freeze action
					BattleAction ba;
					ba.actionType = EActionType::BAD_MORALE;
					ba.side = next->side;
					ba.stackNumber = next->ID;

					makeAutomaticAction(next, ba);
					continue;
				}
			}

			if (next->hasBonusOfType(Bonus::ATTACKS_NEAREST_CREATURE)) //while in berserk
			{
				logGlobal->trace("Handle Berserk effect");
				std::pair<const battle::Unit *, BattleHex> attackInfo = curB.getNearestStack(next);
				if (attackInfo.first != nullptr)
				{
					BattleAction attack;
					attack.actionType = EActionType::WALK_AND_ATTACK;
					attack.side = next->side;
					attack.stackNumber = next->ID;
					attack.aimToHex(attackInfo.second);
					attack.aimToUnit(attackInfo.first);

					makeAutomaticAction(next, attack);
					logGlobal->trace("Attacked nearest target %s", attackInfo.first->getDescription());
				}
				else
				{
					makeStackDoNothing(next);
					logGlobal->trace("No target found");
				}
				continue;
			}

			const CGHeroInstance * curOwner = battleGetOwnerHero(next);
			const int stackCreatureId = next->getCreature()->idNumber;

			if ((stackCreatureId == CreatureID::ARROW_TOWERS || stackCreatureId == CreatureID::BALLISTA)
				&& (!curOwner || getRandomGenerator().nextInt(99) >= curOwner->valOfBonuses(Bonus::MANUAL_CONTROL, stackCreatureId)))
			{
				BattleAction attack;
				attack.actionType = EActionType::SHOOT;
				attack.side = next->side;
				attack.stackNumber = next->ID;

				//TODO: select target by priority

				const battle::Unit * target = nullptr;

				for(auto & elem : gs->curB->stacks)
				{
					if(elem->owner != next->owner && elem->isValidTarget())
					{
						target = elem;
						break;
					}
				}

				if(target == nullptr)
				{
					makeStackDoNothing(next);
				}
				else
				{
					attack.aimToUnit(target);
					makeAutomaticAction(next, attack);
				}
				continue;
			}

			if (next->getCreature()->idNumber == CreatureID::CATAPULT)
			{
				const auto & attackableBattleHexes = curB.getAttackableBattleHexes();

				if (attackableBattleHexes.empty())
				{
					makeStackDoNothing(next);
					continue;
				}

				if (!curOwner || getRandomGenerator().nextInt(99) >= curOwner->valOfBonuses(Bonus::MANUAL_CONTROL, CreatureID::CATAPULT))
				{
					BattleAction attack;
					auto destination = *RandomGeneratorUtil::nextItem(attackableBattleHexes, getRandomGenerator());
					attack.aimToHex(destination);
					attack.actionType = EActionType::CATAPULT;
					attack.side = next->side;
					attack.stackNumber = next->ID;

					makeAutomaticAction(next, attack);
					continue;
				}
			}

			if (next->getCreature()->idNumber == CreatureID::FIRST_AID_TENT)
			{
				TStacks possibleStacks = battleGetStacksIf([=](const CStack * s)
				{
					return s->owner == next->owner && s->canBeHealed();
				});

				if (!possibleStacks.size())
				{
					makeStackDoNothing(next);
					continue;
				}

				if (!curOwner || getRandomGenerator().nextInt(99) >= curOwner->valOfBonuses(Bonus::MANUAL_CONTROL, CreatureID::FIRST_AID_TENT))
				{
					RandomGeneratorUtil::randomShuffle(possibleStacks, getRandomGenerator());
					const CStack * toBeHealed = possibleStacks.front();

					BattleAction heal;
					heal.actionType = EActionType::STACK_HEAL;
					heal.aimToUnit(toBeHealed);
					heal.side = next->side;
					heal.stackNumber = next->ID;

					makeAutomaticAction(next, heal);
					continue;
				}
			}

			int numberOfAsks = 1;
			bool breakOuter = false;
			do
			{//ask interface and wait for answer
				if (!battleResult.get())
				{
					stackTurnTrigger(next); //various effects

					if(next->fear)
					{
						makeStackDoNothing(next); //end immediately if stack was affected by fear
					}
					else
					{
						logGlobal->trace("Activating %s", next->nodeName());
						auto nextId = next->ID;
						BattleSetActiveStack sas;
						sas.stack = nextId;
						sendAndApply(&sas);

						auto actionWasMade = [&]() -> bool
						{
							if (battleMadeAction.data)//active stack has made its action
								return true;
							if (battleResult.get())// battle is finished
								return true;
							if (next == nullptr)//active stack was been removed
								return true;
							return !next->alive();//active stack is dead
						};

						boost::unique_lock<boost::mutex> lock(battleMadeAction.mx);
						battleMadeAction.data = false;
						while (!actionWasMade())
						{
							battleMadeAction.cond.wait(lock);
							if (battleGetStackByID(nextId, false) != next)
								next = nullptr; //it may be removed, while we wait
						}
					}
				}

				if (battleResult.get()) //don't touch it, battle could be finished while waiting got action
				{
					breakOuter = true;
					break;
				}
				//we're after action, all results applied
				checkBattleStateChanges(); //check if this action ended the battle

				if(next != nullptr)
				{
					//check for good morale
					nextStackMorale = next->MoraleVal();
					if(!next->hadMorale  //only one extra move per turn possible
						&& !next->defending
						&& !next->waited()
						&& !next->fear
						&&  next->alive()
						&&  nextStackMorale > 0
						&& !(NBonus::hasOfType(gs->curB->battleGetFightingHero(0), Bonus::BLOCK_MORALE)
							|| NBonus::hasOfType(gs->curB->battleGetFightingHero(1), Bonus::BLOCK_MORALE)) //checking if gs->curB->heroes have (or don't have) morale blocking bonuses
						)
					{
						if(getRandomGenerator().nextInt(23) < nextStackMorale) //this stack hasn't got morale this turn
						{
							BattleTriggerEffect bte;
							bte.stackID = next->ID;
							bte.effect = Bonus::MORALE;
							bte.val = 1;
							bte.additionalInfo = 0;
							sendAndApply(&bte); //play animation

							++numberOfAsks; //move this stack once more
						}
					}
				}
				--numberOfAsks;
			} while (numberOfAsks > 0);

			if (breakOuter)
			{
				break;
			}

		}
		firstRound = false;
	}

	endBattle(gs->curB->tile, gs->curB->battleGetFightingHero(0), gs->curB->battleGetFightingHero(1));
}

bool CGameHandler::makeAutomaticAction(const CStack *stack, BattleAction &ba)
{
	BattleSetActiveStack bsa;
	bsa.stack = stack->ID;
	bsa.askPlayerInterface = false;
	sendAndApply(&bsa);

	bool ret = makeBattleAction(ba);
	checkBattleStateChanges();
	return ret;
}

void CGameHandler::giveHeroArtifact(const CGHeroInstance *h, const CArtifactInstance *a, ArtifactPosition pos)
{
	assert(a->artType);
	ArtifactLocation al;
	al.artHolder = const_cast<CGHeroInstance*>(h);

	ArtifactPosition slot = ArtifactPosition::PRE_FIRST;
	if (pos < 0)
	{
		if (pos == ArtifactPosition::FIRST_AVAILABLE)
			slot = a->firstAvailableSlot(h);
		else
			slot = a->firstBackpackSlot(h);
	}
	else
	{
		slot = pos;
	}

	al.slot = slot;

	if (slot < 0 || !a->canBePutAt(al))
	{
		complain("Cannot put artifact in that slot!");
		return;
	}

	putArtifact(al, a);
}
void CGameHandler::putArtifact(const ArtifactLocation &al, const CArtifactInstance *a)
{
	PutArtifact pa;
	pa.art = a;
	pa.al = al;
	sendAndApply(&pa);
}

bool CGameHandler::giveHeroNewArtifact(const CGHeroInstance * h, const CArtifact * art)
{
	COMPLAIN_RET_FALSE_IF(art->possibleSlots.at(ArtBearer::HERO).empty(), "Not a hero artifact!");

	ArtifactPosition slot = art->possibleSlots.at(ArtBearer::HERO).front();

	COMPLAIN_RET_FALSE_IF(nullptr != h->getArt(slot, false), "Hero already has artifact in slot");

	giveHeroNewArtifact(h, art, slot);
	return true;
}

void CGameHandler::giveHeroNewArtifact(const CGHeroInstance *h, const CArtifact *artType, ArtifactPosition pos)
{
	CArtifactInstance *a = nullptr;
	if (!artType->constituents)
	{
		a = new CArtifactInstance();
	}
	else
	{
		a = new CCombinedArtifactInstance();
	}
	a->artType = artType; //*NOT* via settype -> all bonus-related stuff must be done by NewArtifact apply

	NewArtifact na;
	na.art = a;
	sendAndApply(&na); // -> updates a!!!, will create a on other machines

	giveHeroArtifact(h, a, pos);
}

void CGameHandler::setBattleResult(BattleResult::EResult resultType, int victoriusSide)
{
	boost::unique_lock<boost::mutex> guard(battleResult.mx);
	if (battleResult.data)
	{
		complain((boost::format("The battle result has been already set (to %d, asked to %d)")
		          % battleResult.data->result % resultType).str());
		return;
	}
	auto br = new BattleResult();
	br->result = resultType;
	br->winner = victoriusSide; //surrendering side loses
	gs->curB->calculateCasualties(br->casualties);
	battleResult.data = br;
}

void CGameHandler::commitPackage(CPackForClient *pack)
{
	sendAndApply(pack);
}

void CGameHandler::spawnWanderingMonsters(CreatureID creatureID)
{
	std::vector<int3>::iterator tile;
	std::vector<int3> tiles;
	getFreeTiles(tiles);
	ui32 amount = tiles.size() / 200; //Chance is 0.5% for each tile

	RandomGeneratorUtil::randomShuffle(tiles, getRandomGenerator());
	logGlobal->trace("Spawning wandering monsters. Found %d free tiles. Creature type: %d", tiles.size(), creatureID.num);
	const CCreature *cre = VLC->creh->creatures.at(creatureID);
	for (int i = 0; i < amount; ++i)
	{
		tile = tiles.begin();
		logGlobal->trace("\tSpawning monster at %s", tile->toString());
		putNewMonster(creatureID, cre->getRandomAmount(std::rand), *tile);
		tiles.erase(tile); //not use it again
	}
}

void CGameHandler::handleCheatCode(std::string & cheat, PlayerColor player, const CGHeroInstance * hero, const CGTownInstance * town, bool & cheated)
{
	if (cheat == "vcmiistari")
	{
		if (!hero) return;
		///Give hero spellbook
		if (!hero->hasSpellbook())
			giveHeroNewArtifact(hero, VLC->arth->artifacts[ArtifactID::SPELLBOOK], ArtifactPosition::SPELLBOOK);

		///Give all spells with bonus (to allow banned spells)
		GiveBonus giveBonus(GiveBonus::HERO);
		giveBonus.id = hero->id.getNum();
		giveBonus.bonus = Bonus(Bonus::PERMANENT, Bonus::SPELLS_OF_LEVEL, Bonus::OTHER, 0, 0);
		//start with level 0 to skip abilities
		for (int level = 1; level <= GameConstants::SPELL_LEVELS; level++)
		{
			giveBonus.bonus.subtype = level;
			sendAndApply(&giveBonus);
		}

		///Give mana
		SetMana sm;
		sm.hid = hero->id;
		sm.val = 999;
		sm.absolute = true;
		sendAndApply(&sm);
	}
	else if (cheat == "vcmiarmenelos")
	{
		if (!town) return;
		///Build all buildings in selected town
		for (auto & build : town->town->buildings)
		{
			if (!town->hasBuilt(build.first)
				&& !build.second->Name().empty()
				&& build.first != BuildingID::SHIP)
			{
				buildStructure(town->id, build.first, true);
			}
		}
	}
	else if (cheat == "vcmiainur" || cheat == "vcmiangband" || cheat == "vcmiglaurung")
	{
		if (!hero) return;
		///Gives N creatures into each slot
		std::map<std::string, std::pair<int, int>> creatures;
		creatures.insert(std::make_pair("vcmiainur", std::make_pair(13, 5))); //5 archangels
		creatures.insert(std::make_pair("vcmiangband", std::make_pair(66, 10))); //10 black knights
		creatures.insert(std::make_pair("vcmiglaurung", std::make_pair(133, 5000))); //5000 crystal dragons

		const CCreature * creature = VLC->creh->creatures.at(creatures[cheat].first);
		for (int i = 0; i < GameConstants::ARMY_SIZE; i++)
			if (!hero->hasStackAtSlot(SlotID(i)))
				insertNewStack(StackLocation(hero, SlotID(i)), creature, creatures[cheat].second);
	}
	else if (cheat == "vcminoldor")
	{
		if (!hero) return;
		///Give all war machines to hero
		if (!hero->getArt(ArtifactPosition::MACH1))
			giveHeroNewArtifact(hero, VLC->arth->artifacts[ArtifactID::BALLISTA], ArtifactPosition::MACH1);
		if (!hero->getArt(ArtifactPosition::MACH2))
			giveHeroNewArtifact(hero, VLC->arth->artifacts[ArtifactID::AMMO_CART], ArtifactPosition::MACH2);
		if (!hero->getArt(ArtifactPosition::MACH3))
			giveHeroNewArtifact(hero, VLC->arth->artifacts[ArtifactID::FIRST_AID_TENT], ArtifactPosition::MACH3);
	}
	else if (cheat == "vcmiforgeofnoldorking")
	{
		if (!hero) return;
		///Give hero all artifacts except war machines, spell scrolls and spell book
		for (int g = 7; g < VLC->arth->artifacts.size(); ++g) //including artifacts from mods
			giveHeroNewArtifact(hero, VLC->arth->artifacts[g], ArtifactPosition::PRE_FIRST);
	}
	else if (cheat == "vcmiglorfindel")
	{
		if (!hero) return;
		///selected hero gains a new level
		changePrimSkill(hero, PrimarySkill::EXPERIENCE, VLC->heroh->reqExp(hero->level + 1) - VLC->heroh->reqExp(hero->level));
	}
	else if (cheat == "vcminahar")
	{
		if (!hero) return;
		///Give 1000000 movement points to hero
		SetMovePoints smp;
		smp.hid = hero->id;
		smp.val = 1000000;
		sendAndApply(&smp);

		GiveBonus gb(GiveBonus::HERO);
		gb.bonus.type = Bonus::FREE_SHIP_BOARDING;
		gb.bonus.duration = Bonus::ONE_DAY;
		gb.bonus.source = Bonus::OTHER;
		gb.id = hero->id.getNum();
		giveHeroBonus(&gb);
	}
	else if (cheat == "vcmiformenos")
	{
		///Give resources to player
		TResources resources;
		resources[Res::GOLD] = 100000;
		for (Res::ERes i = Res::WOOD; i < Res::GOLD; vstd::advance(i, 1))
			resources[i] = 100;

		giveResources(player, resources);
	}
	else if (cheat == "vcmisilmaril")
	{
		///Player wins
		PlayerCheated pc;
		pc.player = player;
		pc.winningCheatCode = true;
		sendAndApply(&pc);
	}
	else if (cheat == "vcmimelkor")
	{
		///Player looses
		PlayerCheated pc;
		pc.player = player;
		pc.losingCheatCode = true;
		sendAndApply(&pc);
	}
	else if (cheat == "vcmieagles" || cheat == "vcmiungoliant")
	{
		///Reveal or conceal FoW
		FoWChange fc;
		fc.mode = (cheat == "vcmieagles" ? 1 : 0);
		fc.player = player;
		const auto & fowMap = gs->getPlayerTeam(player)->fogOfWarMap;
		auto hlp_tab = new int3[gs->map->width * gs->map->height * (gs->map->twoLevel ? 2 : 1)];
		int lastUnc = 0;
		for (int i = 0; i < gs->map->width; i++)
			for (int j = 0; j < gs->map->height; j++)
				for (int k = 0; k < (gs->map->twoLevel ? 2 : 1); k++)
					if (!fowMap.at(i).at(j).at(k) || !fc.mode)
						hlp_tab[lastUnc++] = int3(i, j, k);
		fc.tiles.insert(hlp_tab, hlp_tab + lastUnc);
		delete [] hlp_tab;
		sendAndApply(&fc);
	}
	else
		cheated = false;
}

void CGameHandler::removeObstacle(const CObstacleInstance & obstacle)
{
	BattleObstaclesChanged obsRem;
	obsRem.changes.emplace_back(obstacle.uniqueID, BattleChanges::EOperation::REMOVE);
	sendAndApply(&obsRem);
}

void CGameHandler::synchronizeArtifactHandlerLists()
{
	UpdateArtHandlerLists uahl;
	uahl.treasures = VLC->arth->treasures;
	uahl.minors = VLC->arth->minors;
	uahl.majors = VLC->arth->majors;
	uahl.relics = VLC->arth->relics;
	sendAndApply(&uahl);
}

bool CGameHandler::isValidObject(const CGObjectInstance *obj) const
{
	return vstd::contains(gs->map->objects, obj);
}

bool CGameHandler::isBlockedByQueries(const CPack *pack, PlayerColor player)
{
	if (!strcmp(typeid(*pack).name(), typeid(PlayerMessage).name()))
		return false;

	auto query = queries.topQuery(player);
	if (query && query->blocksPack(pack))
	{
		complain(boost::str(boost::format("Player %s has to answer queries  before attempting any further actions. Top query is %s!") % player % query->toString()));
		return true;
	}

	return false;
}

void CGameHandler::removeAfterVisit(const CGObjectInstance *object)
{
	//If the object is being visited, there must be a matching query
	for (const auto &query : queries.allQueries())
	{
		if (auto someVistQuery = std::dynamic_pointer_cast<CObjectVisitQuery>(query))
		{
			if (someVistQuery->visitedObject == object)
			{
				someVistQuery->removeObjectAfterVisit = true;
				return;
			}
		}
	}

	//If we haven't returned so far, there is no query and no visit, call was wrong
	assert("This function needs to be called during the object visit!");
}

void CGameHandler::changeFogOfWar(int3 center, ui32 radius, PlayerColor player, bool hide)
{
	std::unordered_set<int3, ShashInt3> tiles;
	getTilesInRange(tiles, center, radius, player, hide? -1 : 1);
	if (hide)
	{
		std::unordered_set<int3, ShashInt3> observedTiles; //do not hide tiles observed by heroes. May lead to disastrous AI problems
		auto p = getPlayer(player);
		for (auto h : p->heroes)
		{
			getTilesInRange(observedTiles, h->getSightCenter(), h->getSightRadius(), h->tempOwner, -1);
		}
		for (auto t : p->towns)
		{
			getTilesInRange(observedTiles, t->getSightCenter(), t->getSightRadius(), t->tempOwner, -1);
		}
		for (auto tile : observedTiles)
			vstd::erase_if_present (tiles, tile);
	}
	changeFogOfWar(tiles, player, hide);
}

void CGameHandler::changeFogOfWar(std::unordered_set<int3, ShashInt3> &tiles, PlayerColor player, bool hide)
{
	FoWChange fow;
	fow.tiles = tiles;
	fow.player = player;
	fow.mode = hide? 0 : 1;
	sendAndApply(&fow);
}

bool CGameHandler::isVisitCoveredByAnotherQuery(const CGObjectInstance *obj, const CGHeroInstance *hero)
{
	if (auto topQuery = queries.topQuery(hero->getOwner()))
		if (auto visit = std::dynamic_pointer_cast<const CObjectVisitQuery>(topQuery))
			return !(visit->visitedObject == obj && visit->visitingHero == hero);

	return true;
}

CasualtiesAfterBattle::CasualtiesAfterBattle(const CArmedInstance * _army, BattleInfo *bat):
	army(_army)
{
	heroWithDeadCommander = ObjectInstanceID();

	PlayerColor color = army->tempOwner;
	if(color == PlayerColor::UNFLAGGABLE)
		color = PlayerColor::NEUTRAL;

	for(CStack * st : bat->stacks)
	{
		if(st->summoned) //don't take into account temporary summoned stacks
			continue;
		if(st->owner != color) //remove only our stacks
			continue;

		logGlobal->debug("Calculating casualties for %s", st->nodeName());

		st->health.takeResurrected();

		if(st->slot == SlotID::ARROW_TOWERS_SLOT)
		{
			logGlobal->debug("Ignored arrow towers stack.");
		}
		else if(st->slot == SlotID::WAR_MACHINES_SLOT)
		{
			auto warMachine = st->type->warMachine;

			if(warMachine == ArtifactID::NONE)
			{
				logGlobal->error("Invalid creature in war machine virtual slot. Stack: %s", st->nodeName());
			}
			//catapult artifact remain even if "creature" killed in siege
			else if(warMachine != ArtifactID::CATAPULT && st->getCount() <= 0)
			{
				logGlobal->debug("War machine has been destroyed");
				auto hero = dynamic_ptr_cast<CGHeroInstance> (army);
				if (hero)
					removedWarMachines.push_back (ArtifactLocation(hero, hero->getArtPos(warMachine, true)));
				else
					logGlobal->error("War machine in army without hero");
			}
		}
		else if(st->slot == SlotID::SUMMONED_SLOT_PLACEHOLDER)
		{
			if(st->alive() && st->getCount() > 0)
			{
				logGlobal->debug("Permanently summoned %d units.", st->getCount());
				const CreatureID summonedType = st->type->idNumber;
				summoned[summonedType] += st->getCount();
			}
		}
		else if(st->slot == SlotID::COMMANDER_SLOT_PLACEHOLDER)
		{
			if (nullptr == st->base)
			{
				logGlobal->error("Stack with no base in commander slot. Stack: %s", st->nodeName());
			}
			else
			{
				auto c = dynamic_cast <const CCommanderInstance *>(st->base);
				if(c)
				{
					auto h = dynamic_cast <const CGHeroInstance *>(army);
					if(h && h->commander == c && (st->getCount() == 0 || !st->alive()))
					{
						logGlobal->debug("Commander is dead.");
						heroWithDeadCommander = army->id; //TODO: unify commander handling
					}
				}
				else
					logGlobal->error("Stack with invalid instance in commander slot. Stack: %s", st->nodeName());
			}
		}
		else if(st->base && !army->slotEmpty(st->slot))
		{
			logGlobal->debug("Count: %d; base count: %d", st->getCount(), army->getStackCount(st->slot));
			if(st->getCount() == 0 || !st->alive())
			{
				logGlobal->debug("Stack has been destroyed.");
				StackLocation sl(army, st->slot);
				newStackCounts.push_back(TStackAndItsNewCount(sl, 0));
			}
			else if(st->getCount() < army->getStackCount(st->slot))
			{
				logGlobal->debug("Stack lost %d units.", army->getStackCount(st->slot) - st->getCount());
				StackLocation sl(army, st->slot);
				newStackCounts.push_back(TStackAndItsNewCount(sl, st->getCount()));
			}
			else if(st->getCount() > army->getStackCount(st->slot))
			{
				logGlobal->debug("Stack gained %d units.", st->getCount() - army->getStackCount(st->slot));
				StackLocation sl(army, st->slot);
				newStackCounts.push_back(TStackAndItsNewCount(sl, st->getCount()));
			}
		}
		else
		{
			logGlobal->warn("Unable to process stack: %s", st->nodeName());
		}
	}
}

void CasualtiesAfterBattle::updateArmy(CGameHandler *gh)
{
	for (TStackAndItsNewCount &ncount : newStackCounts)
	{
		if (ncount.second > 0)
			gh->changeStackCount(ncount.first, ncount.second, true);
		else
			gh->eraseStack(ncount.first, true);
	}
	for (auto summoned_iter : summoned)
	{
		SlotID slot = army->getSlotFor(summoned_iter.first);
		if (slot.validSlot())
		{
			StackLocation location(army, slot);
			gh->addToSlot(location, summoned_iter.first.toCreature(), summoned_iter.second);
		}
		else
		{
			//even if it will be possible to summon anything permanently it should be checked for free slot
			//necromancy is handled separately
			gh->complain("No free slot to put summoned creature");
		}
	}
	for (auto al : removedWarMachines)
	{
		gh->removeArtifact(al);
	}
	if (heroWithDeadCommander != ObjectInstanceID())
	{
		SetCommanderProperty scp;
		scp.heroid = heroWithDeadCommander;
		scp.which = SetCommanderProperty::ALIVE;
		scp.amount = 0;
		gh->sendAndApply(&scp);
	}
}

CGameHandler::FinishingBattleHelper::FinishingBattleHelper(std::shared_ptr<const CBattleQuery> Query, int RemainingBattleQueriesCount)
{
	assert(Query->result);
	assert(Query->bi);
	auto &result = *Query->result;
	auto &info = *Query->bi;

	winnerHero = result.winner != 0 ? info.sides[1].hero : info.sides[0].hero;
	loserHero = result.winner != 0 ? info.sides[0].hero : info.sides[1].hero;
	victor = info.sides[result.winner].color;
	loser = info.sides[!result.winner].color;
	remainingBattleQueriesCount = RemainingBattleQueriesCount;
}

CGameHandler::FinishingBattleHelper::FinishingBattleHelper()
{
	winnerHero = loserHero = nullptr;
	remainingBattleQueriesCount = 0;
}

CRandomGenerator & CGameHandler::getRandomGenerator()
{
	return CRandomGenerator::getDefault();
}

///ServerSpellCastEnvironment
ServerSpellCastEnvironment::ServerSpellCastEnvironment(CGameHandler * gh): gh(gh)
{

}

void ServerSpellCastEnvironment::sendAndApply(CPackForClient * pack) const
{
	gh->sendAndApply(pack);
}

CRandomGenerator & ServerSpellCastEnvironment::getRandomGenerator() const
{
	return gh->getRandomGenerator();
}

void ServerSpellCastEnvironment::complain(const std::string& problem) const
{
	gh->complain(problem);
}

const CGameInfoCallback * ServerSpellCastEnvironment::getCb() const
{
	return gh;
}

const CMap * ServerSpellCastEnvironment::getMap() const
{
	return gh->gameState()->map;
}

bool ServerSpellCastEnvironment::moveHero(ObjectInstanceID hid, int3 dst, bool teleporting) const
{
	return gh->moveHero(hid, dst, teleporting, false);
}

void ServerSpellCastEnvironment::genericQuery(Query * request, PlayerColor color, std::function<void(const JsonNode&)> callback) const
{
	auto query = std::make_shared<CGenericQuery>(&gh->queries, color, callback);
	request->queryID = query->queryID;
	gh->queries.addQuery(query);
	gh->sendAndApply(request);
}