vcmi/lib/CSpellHandler.h

#pragma once

#include "IHandlerBase.h"
#include "../lib/ConstTransitivePtr.h"
#include "int3.h"
#include "GameConstants.h"
#include "BattleHex.h"
#include "HeroBonus.h"


/*
 * CSpellHandler.h, 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
 *
 */

class CSpell;
class ISpellMechanics;

class CLegacyConfigParser;

class CGHeroInstance;
class CStack;

class CBattleInfoCallback;

struct CPackForClient;

struct SpellSchoolInfo
{
	ESpellSchool id; //backlink
	Bonus::BonusType damagePremyBonus;
	Bonus::BonusType immunityBonus;	
	std::string jsonName;	
};

static SpellSchoolInfo spellSchoolConfig[4] = 
{
	{
		ESpellSchool::AIR,
		Bonus::AIR_SPELL_DMG_PREMY,
		Bonus::AIR_IMMUNITY,
		"air"
	},
	{
		ESpellSchool::FIRE,
		Bonus::FIRE_SPELL_DMG_PREMY,
		Bonus::FIRE_IMMUNITY,
		"fire"
	},
	{
		ESpellSchool::WATER,
		Bonus::WATER_SPELL_DMG_PREMY,
		Bonus::WATER_IMMUNITY,
		"water"
	},
	{
		ESpellSchool::EARTH,
		Bonus::EARTH_SPELL_DMG_PREMY,
		Bonus::EARTH_IMMUNITY,
		"earth"
	}
};

///callback to be provided by server
class DLL_LINKAGE SpellCastEnvironment
{
public:
	virtual void sendAndApply(CPackForClient * info) = 0;
};

///helper struct
struct DLL_LINKAGE SpellCastContext
{
public:
	SpellCastEnvironment * env;
	
	int spellLvl;
//	BattleHex destination;
	ui8 casterSide;
	PlayerColor casterColor;
	CGHeroInstance * caster;
	CGHeroInstance * secHero;
	int usedSpellPower;
	ECastingMode::ECastingMode mode;
	CStack * targetStack;
	CStack * selectedStack;	
};


class DLL_LINKAGE CSpell
{
public:
	struct LevelInfo
	{
		std::string description; //descriptions of spell for skill level
		si32 cost; //per skill level: 0 - none, 1 - basic, etc
		si32 power; //per skill level: 0 - none, 1 - basic, etc
		si32 AIValue; //AI values: per skill level: 0 - none, 1 - basic, etc

		bool smartTarget;
		std::string range;

		std::vector<Bonus> effects;

		LevelInfo();
		~LevelInfo();

		template <typename Handler> void serialize(Handler &h, const int version)
		{
			h & description & cost & power & AIValue & smartTarget & range & effects;
		}
	};

	/** \brief Low level accessor. Don`t use it if absolutely necessary
	 *
	 * \param level. spell school level
	 * \return Spell level info structure
	 *
	 */
	const CSpell::LevelInfo& getLevelInfo(const int level) const;
public:
	enum ETargetType {NO_TARGET, CREATURE, OBSTACLE};
	enum ESpellPositiveness {NEGATIVE = -1, NEUTRAL = 0, POSITIVE = 1};

	struct TargetInfo
	{
		ETargetType type;
		bool smart;
		bool massive;
		bool onlyAlive;
		///no immunity on primary target (mostly spell-like attack)
		bool alwaysHitDirectly;
	};

	SpellID id;
	std::string identifier; //???
	std::string name;

	si32 level;
	bool earth; //deprecated
	bool water; //deprecated
	bool fire;  //deprecated
	bool air;   //deprecated
	
	std::map<ESpellSchool, bool> school; //todo: use this instead of separate boolean fields
	
	si32 power; //spell's power

	std::map<TFaction, si32> probabilities; //% chance to gain for castles

	bool combatSpell; //is this spell combat (true) or adventure (false)
	bool creatureAbility; //if true, only creatures can use this spell
	si8 positiveness; //1 if spell is positive for influenced stacks, 0 if it is indifferent, -1 if it's negative

	std::vector<SpellID> counteredSpells; //spells that are removed when effect of this spell is placed on creature (for bless-curse, haste-slow, and similar pairs)

	CSpell();
	~CSpell();

	std::vector<BattleHex> rangeInHexes(BattleHex centralHex, ui8 schoolLvl, ui8 side, bool *outDroppedHexes = nullptr ) const; //convert range to specific hexes; last optional out parameter is set to true, if spell would cover unavailable hexes (that are not included in ret)
	si16 mainEffectAnim; //main spell effect animation, in AC format (or -1 when none)
	ETargetType getTargetType() const; //deprecated

	CSpell::TargetInfo getTargetInfo(const int level) const;
	CSpell::TargetInfo getTargetInfoEx(const int level, ECastingMode::ECastingMode mode) const;

	bool isCombatSpell() const;
	bool isAdventureSpell() const;
	bool isCreatureAbility() const;

	bool isPositive() const;
	bool isNegative() const;
	bool isNeutral() const;

	bool isDamageSpell() const;
	bool isHealingSpell() const;
	bool isRisingSpell() const;	
	bool isOffensiveSpell() const;

	bool isSpecialSpell() const;

	bool hasEffects() const;
	void getEffects(std::vector<Bonus> &lst, const int level) const;
	
	//internal, for use only by Mechanics classes
	ESpellCastProblem::ESpellCastProblem isImmuneBy(const IBonusBearer *obj) const;
	
	//checks for creature immunity / anything that prevent casting *at given hex* - doesn't take into acount general problems such as not having spellbook or mana points etc.
	ESpellCastProblem::ESpellCastProblem isImmuneByStack(const CGHeroInstance * caster, const CStack * obj) const;
	
	//internal, for use only by Mechanics classes. applying secondary skills
	ui32 calculateBonus(ui32 baseDamage, const CGHeroInstance * caster, const CStack * affectedCreature) const;
	
	ui32 calculateDamage(const CGHeroInstance * caster, const CStack * affectedCreature, int spellSchoolLevel, int usedSpellPower) const;
	
	///calculate healed HP for all spells casted by hero
	ui32 calculateHealedHP(const CGHeroInstance * caster, const CStack * stack, const CStack * sacrificedStack = nullptr) const;
	
	///selects from allStacks actually affected stacks
	std::set<const CStack *> getAffectedStacks(const CBattleInfoCallback * cb, ECastingMode::ECastingMode mode, PlayerColor casterColor, int spellLvl, BattleHex destination, const CGHeroInstance * caster = nullptr) const;

	si32 getCost(const int skillLevel) const;

	/**
	 * Returns spell level power, base power ignored
	 */
	si32 getPower(const int skillLevel) const;

//	/**
//	* Returns spell power, taking base power into account
//	*/
//	si32 calculatePower(const int skillLevel) const;


	si32 getProbability(const TFaction factionId) const;

	/**
	 * Returns resource name of icon for SPELL_IMMUNITY bonus
	 */
	const std::string& getIconImmune() const;

	const std::string& getCastSound() const;

	template <typename Handler> void serialize(Handler &h, const int version)
	{
		h & identifier & id & name & level & earth & water & fire & air & power
		  & probabilities  & attributes & combatSpell & creatureAbility & positiveness & counteredSpells & mainEffectAnim;
		h & isRising & isDamage & isOffensive;
		h & targetType;
		h & immunities & limiters & absoluteImmunities & absoluteLimiters;
		h & iconImmune;
		h & defaultProbability;

		h & isSpecial;

		h & castSound & iconBook & iconEffect & iconScenarioBonus & iconScroll;

		h & levels;
		
		if(!h.saving)
			setup();
	}
	friend class CSpellHandler;
	friend class Graphics;

private:
	void setIsOffensive(const bool val);
	void setIsRising(const bool val);
	
	//call this after load or deserialization. cant be done in constructor.
	void setup();
	void setupMechanics();
private:
	si32 defaultProbability;

	bool isRising;
	bool isDamage;
	bool isOffensive;
	bool isSpecial;

	std::string attributes; //reference only attributes //todo: remove or include in configuration format, currently unused

	ETargetType targetType;

	std::vector<Bonus::BonusType> immunities; //any of these grants immunity
	std::vector<Bonus::BonusType> absoluteImmunities; //any of these grants immunity, can't be negated
	std::vector<Bonus::BonusType> limiters; //all of them are required to be affected
	std::vector<Bonus::BonusType> absoluteLimiters; //all of them are required to be affected, can't be negated

	///graphics related stuff

	std::string iconImmune;

	std::string iconBook;
	std::string iconEffect;
	std::string iconScenarioBonus;
	std::string iconScroll;

	///sound related stuff
	std::string castSound;

	std::vector<LevelInfo> levels;
	
	ISpellMechanics * mechanics;//(!) do not serialize
};

class DLL_LINKAGE ISpellMechanics
{
public:
	
	struct SpellTargetingContext
	{
		CBattleInfoCallback * cb;
		
		CSpell::TargetInfo ti;
	};
	
public:
	ISpellMechanics(CSpell * s);
	virtual ~ISpellMechanics(){};	
	
	virtual std::set<const CStack *> getAffectedStacks(SpellTargetingContext & ctx) const = 0;
	
	virtual ESpellCastProblem::ESpellCastProblem isImmuneByStack(const CGHeroInstance * caster, const CStack * obj) const = 0;
	
	
    /** \brief 
     *
     * \param 
     * \return true if no error
     *
     */                           
	virtual bool adventureCast(SpellCastContext & context) const = 0; 
	virtual bool battleCast(SpellCastContext & context) const = 0; 	
	
protected:
	CSpell * owner;	
};


bool DLL_LINKAGE isInScreenRange(const int3 &center, const int3 &pos); //for spells like Dimension Door

class DLL_LINKAGE CSpellHandler: public CHandlerBase<SpellID, CSpell>
{
public:
	CSpellHandler();
	virtual ~CSpellHandler();

	///IHandler base
	std::vector<JsonNode> loadLegacyData(size_t dataSize) override;
	void afterLoadFinalization() override;
	void beforeValidate(JsonNode & object) override;

	/**
	 * Gets a list of default allowed spells. OH3 spells are all allowed by default.
	 *
	 * @return a list of allowed spells, the index is the spell id and the value either 0 for not allowed or 1 for allowed
	 */
	std::vector<bool> getDefaultAllowed() const override;

	const std::string getTypeName() const override;

	template <typename Handler> void serialize(Handler &h, const int version)
	{
		h & objects ;
	}
protected:
	CSpell * loadFromJson(const JsonNode & json) override;
};