One more file:

* lib/IGameEventsReceiver.h

Workaround for crash on post-visit.

lib/ERMScriptModule.cpp

@@ -33,6 +33,9 @@ void CERMScriptModule::init()
 
 void CERMScriptModule::heroVisit(const CGHeroInstance *visitor, const CGObjectInstance *visitedObj, bool start)
 {
+	if(!visitedObj)
+		return;
+
 	ERMInterpreter::TIDPattern tip;
 	tip[1] = list_of(visitedObj->ID);
 	tip[2] = list_of(visitedObj->ID)(visitedObj->subID);

lib/IGameEventsReceiver.h

@@ -0,0 +1,113 @@
+#pragma once
+#include "../global.h"
+#include <set>
+
+class CGTownInstance;
+class CCreature;
+class CArmedInstance;
+struct StackLocation;
+struct TryMoveHero;
+struct ArtifactLocation;
+class CGHeroInstance;
+class CCallback;
+class IShipyard;
+class CGDwelling;
+struct Component;
+class CStackInstance;
+class CGBlackMarket;
+class CGObjectInstance;
+struct Bonus;
+class IMarket;
+struct SetObjectProperty;
+struct PackageApplied;
+struct BattleAction;
+struct BattleStackAttacked;
+struct BattleResult;
+struct BattleSpellCast;
+struct CatapultAttack;
+struct BattleStacksRemoved;
+class CStack;
+class CCreatureSet;
+struct BattleAttack;
+struct SetStackEffect;
+
+
+class DLL_EXPORT IBattleEventsReceiver
+{
+public:
+	virtual void actionFinished(const BattleAction *action){};//occurs AFTER every action taken by any stack or by the hero
+	virtual void actionStarted(const BattleAction *action){};//occurs BEFORE every action taken by any stack or by the hero
+	virtual void battleAttack(const BattleAttack *ba){}; //called when stack is performing attack
+	virtual void battleStacksAttacked(const std::vector<BattleStackAttacked> & bsa){}; //called when stack receives damage (after battleAttack())
+	virtual void battleEnd(const BattleResult *br){};
+	virtual void battleNewRoundFirst(int round){}; //called at the beginning of each turn before changes are applied;
+	virtual void battleNewRound(int round){}; //called at the beginning of each turn, round=-1 is the tactic phase, round=0 is the first "normal" turn
+	virtual void battleStackMoved(const CStack * stack, THex dest, int distance, bool end){};
+	virtual void battleSpellCast(const BattleSpellCast *sc){};
+	virtual void battleStacksEffectsSet(const SetStackEffect & sse){};//called when a specific effect is set to stacks
+	virtual void battleStart(const CCreatureSet *army1, const CCreatureSet *army2, int3 tile, const CGHeroInstance *hero1, const CGHeroInstance *hero2, bool side){}; //called by engine when battle starts; side=0 - left, side=1 - right
+	virtual void battleStacksHealedRes(const std::vector<std::pair<ui32, ui32> > & healedStacks, bool lifeDrain, si32 lifeDrainFrom){}; //called when stacks are healed / resurrected first element of pair - stack id, second - healed hp
+	virtual void battleNewStackAppeared(const CStack * stack){}; //not called at the beginning of a battle or by resurrection; called eg. when elemental is summoned
+	virtual void battleObstaclesRemoved(const std::set<si32> & removedObstacles){}; //called when a certain set  of obstacles is removed from batlefield; IDs of them are given
+	virtual void battleCatapultAttacked(const CatapultAttack & ca){}; //called when catapult makes an attack
+	virtual void battleStacksRemoved(const BattleStacksRemoved & bsr){}; //called when certain stack is completely removed from battlefield
+};
+
+class DLL_EXPORT IGameEventsReceiver
+{
+public:
+	virtual void buildChanged(const CGTownInstance *town, int buildingID, int what){}; //what: 1 - built, 2 - demolished
+
+	virtual void battleResultsApplied(){}; //called when all effects of last battle are applied
+
+	//garrison operations
+	virtual void stackChagedCount(const StackLocation &location, const TQuantity &change, bool isAbsolute){}; //if absolute, change is the new count; otherwise count was modified by adding change
+	virtual void stackChangedType(const StackLocation &location, const CCreature &newType){}; //used eg. when upgrading creatures
+	virtual void stacksErased(const StackLocation &location){}; //stack removed from previously filled slot
+	virtual void stacksSwapped(const StackLocation &loc1, const StackLocation &loc2){};
+	virtual void newStackInserted(const StackLocation &location, const CStackInstance &stack){}; //new stack inserted at given (previously empty position)
+	virtual void stacksRebalanced(const StackLocation &src, const StackLocation &dst, TQuantity count){}; //moves creatures from src stack to dst slot, may be used for merging/splittint/moving stacks
+	//virtual void garrisonChanged(const CGObjectInstance * obj){};
+
+	//artifacts operations
+	virtual void artifactPut(const ArtifactLocation &al){};
+	virtual void artifactRemoved(const ArtifactLocation &al){};
+	virtual void artifactAssembled(const ArtifactLocation &al){};
+	virtual void artifactDisassembled(const ArtifactLocation &al){};
+	virtual void artifactMoved(const ArtifactLocation &src, const ArtifactLocation &dst){};
+
+	virtual void heroVisit(const CGHeroInstance *visitor, const CGObjectInstance *visitedObj, bool start){};
+	virtual void heroCreated(const CGHeroInstance*){};
+	virtual void heroInGarrisonChange(const CGTownInstance *town){};
+	virtual void heroMoved(const TryMoveHero & details){};
+	virtual void heroPrimarySkillChanged(const CGHeroInstance * hero, int which, si64 val){};
+	virtual void heroSecondarySkillChanged(const CGHeroInstance * hero, int which, int val){};
+	virtual void heroManaPointsChanged(const CGHeroInstance * hero){} //not called at the beginning of turn and after spell casts
+	virtual void heroMovePointsChanged(const CGHeroInstance * hero){} //not called at the beginning of turn and after movement
+	virtual void heroVisitsTown(const CGHeroInstance* hero, const CGTownInstance * town){};
+	virtual void receivedResource(int type, int val){};
+	virtual void showInfoDialog(const std::string &text, const std::vector<Component*> &components, int soundID){};
+	virtual void showRecruitmentDialog(const CGDwelling *dwelling, const CArmedInstance *dst, int level){}
+	virtual void showShipyardDialog(const IShipyard *obj){} //obj may be town or shipyard; state: 0 - can buid, 1 - lack of resources, 2 - dest tile is blocked, 3 - no water
+
+	virtual void showPuzzleMap(){};
+	virtual void showMarketWindow(const IMarket *market, const CGHeroInstance *visitor){};
+	virtual void showUniversityWindow(const IMarket *market, const CGHeroInstance *visitor){};
+	virtual void showHillFortWindow(const CGObjectInstance *object, const CGHeroInstance *visitor){};
+	virtual void showTavernWindow(const CGObjectInstance *townOrTavern){};
+	virtual void advmapSpellCast(const CGHeroInstance * caster, int spellID){}; //called when a hero casts a spell
+	virtual void tileHidden(const boost::unordered_set<int3, ShashInt3> &pos){};
+	virtual void tileRevealed(const boost::unordered_set<int3, ShashInt3> &pos){};
+	virtual void newObject(const CGObjectInstance * obj){}; //eg. ship built in shipyard
+	virtual void availableArtifactsChanged(const CGBlackMarket *bm = NULL){}; //bm may be NULL, then artifacts are changed in the global pool (used by merchants in towns)
+	virtual void centerView (int3 pos, int focusTime){};
+	virtual void availableCreaturesChanged(const CGDwelling *town){};
+	virtual void heroBonusChanged(const CGHeroInstance *hero, const Bonus &bonus, bool gain){};//if gain hero received bonus, else he lost it
+	virtual void playerBonusChanged(const Bonus &bonus, bool gain){};//if gain hero received bonus, else he lost it
+	virtual void requestRealized(PackageApplied *pa){};
+	virtual void heroExchangeStarted(si32 hero1, si32 hero2){};
+	virtual void objectPropertyChanged(const SetObjectProperty * sop){}; //eg. mine has been flagged
+	virtual void objectRemoved(const CGObjectInstance *obj){}; //eg. collected resource, picked artifact, beaten hero
+	virtual void playerBlocked(int reason){}; //reason: 0 - upcoming battle
+	virtual void gameOver(ui8 player, bool victory){}; //player lost or won the game
+};