vcmi/client/BattleInterface/CBattleAnimations.h

#pragma once

#include "../CAnimation.h"
#include "../../lib/BattleHex.h"

class CBattleInterface;
class CStack;
class CCreatureAnimation;
struct CatapultProjectileInfo;
struct StackAttackedInfo;

/*
 * CBattleAnimations.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
 *
 */

/// Base class of battle animations
class CBattleAnimation
{
protected:
	CBattleInterface * owner;
public:
	virtual bool init()=0; //to be called - if returned false, call again until returns true
	virtual void nextFrame()=0; //call every new frame
	virtual void endAnim(); //to be called mostly internally; in this class it removes animation from pendingAnims list

	bool isEarliest(bool perStackConcurrency); //determines if this animation is earliest of all

	ui32 ID; //unique identifier

	CBattleAnimation(CBattleInterface * _owner);
};

/// Sub-class which is responsible for managing the battle stack animation.
class CBattleStackAnimation : public CBattleAnimation
{
public:
	const CStack * stack; //id of stack whose animation it is

	CBattleStackAnimation(CBattleInterface * _owner, const CStack * _stack);
	
	static bool isToReverseHlp(BattleHex hexFrom, BattleHex hexTo, bool curDir); //helper for isToReverse
	static bool isToReverse(BattleHex hexFrom, BattleHex hexTo, bool curDir /*if true, creature is in attacker's direction*/, bool toDoubleWide, bool toDir); //determines if creature should be reversed (it stands on hexFrom and should 'see' hexTo)

	CCreatureAnimation * myAnim(); //animation for our stack
};

/// This class is responsible for managing the battle attack animation
class CAttackAnimation : public CBattleStackAnimation
{
protected:
	BattleHex dest; //attacked hex
	bool shooting;
	CCreatureAnim::EAnimType group; //if shooting is true, print this animation group
	const CStack *attackedStack;
	const CStack *attackingStack;
	int attackingStackPosBeforeReturn; //for stacks with return_after_strike feature
public:
	void nextFrame();
	bool checkInitialConditions();

	CAttackAnimation(CBattleInterface *_owner, const CStack *attacker, BattleHex _dest, const CStack *defender);
};

/// Animation of a defending unit
class CDefenceAnimation : public CBattleStackAnimation
{
private:
	//std::vector<StackAttackedInfo> attackedInfos;
	int dmg; //damage dealt
	int amountKilled; //how many creatures in stack has been killed
	const CStack * attacker; //attacking stack
	bool byShooting; //if true, stack has been attacked by shooting
	bool killed; //if true, stack has been killed
public:
	bool init();
	void nextFrame();
	void endAnim();

	CDefenceAnimation(StackAttackedInfo _attackedInfo, CBattleInterface * _owner);
};

class CDummyAnimation : public CBattleAnimation
{
private:
	int counter;
	int howMany;
public:
	bool init();
	void nextFrame();
	void endAnim();

	CDummyAnimation(CBattleInterface * _owner, int howManyFrames);
};

/// Hand-to-hand attack
class CMeleeAttackAnimation : public CAttackAnimation
{
public:
	bool init();
	void nextFrame();
	void endAnim();

	CMeleeAttackAnimation(CBattleInterface * _owner, const CStack * attacker, BattleHex _dest, const CStack * _attacked);
};

/// Move animation of a creature
class CMovementAnimation : public CBattleStackAnimation
{
private:
	std::vector<BattleHex> destTiles; //destination
	BattleHex nextHex;
	ui32 nextPos;
	int distance;
	double stepX, stepY; //how far stack is moved in one frame
	double posX, posY;
	int steps, whichStep;
	int curStackPos; //position of stack before move
public:
	bool init();
	void nextFrame();
	void endAnim();

	CMovementAnimation(CBattleInterface *_owner, const CStack *_stack, std::vector<BattleHex> _destTiles, int _distance);
};

/// Move end animation of a creature
class CMovementEndAnimation : public CBattleStackAnimation
{
private:
	BattleHex destinationTile;
public:
	bool init();
	void nextFrame();
	void endAnim();

	CMovementEndAnimation(CBattleInterface * _owner, const CStack * _stack, BattleHex destTile);
};

/// Move start animation of a creature
class CMovementStartAnimation : public CBattleStackAnimation
{
public:
	bool init();
	void nextFrame();
	void endAnim();

	CMovementStartAnimation(CBattleInterface * _owner, const CStack * _stack);
};

/// Class responsible for animation of stack chaning direction (left <-> right)
class CReverseAnimation : public CBattleStackAnimation
{
private:
	int partOfAnim; //1 - first, 2 - second
	bool secondPartSetup;
	BattleHex hex;
public:
	bool priority; //true - high, false - low
	bool init();
	void nextFrame();

	void setupSecondPart();
	void endAnim();

	CReverseAnimation(CBattleInterface * _owner, const CStack * stack, BattleHex dest, bool _priority);
};

/// Small struct which contains information about the position and the velocity of a projectile
struct ProjectileInfo
{
	double x, y; //position on the screen
	double dx, dy; //change in position in one step
	int step, lastStep; //to know when finish showing this projectile
	int creID; //ID of creature that shot this projectile
	int stackID; //ID of stack
	int frameNum; //frame to display form projectile animation
	bool spin; //if true, frameNum will be increased
	int animStartDelay; //how many times projectile must be attempted to be shown till it's really show (decremented after hit)
	bool reverse; //if true, projectile will be flipped by vertical asix
	CatapultProjectileInfo * catapultInfo; // holds info about the parabolic trajectory of the cannon
};

/// Shooting attack
class CShootingAnimation : public CAttackAnimation
{
private:
	int catapultDamage;
	bool catapult;
public:
	bool init();
	void nextFrame();
	void endAnim();

	//last two params only for catapult attacks
	CShootingAnimation(CBattleInterface * _owner, const CStack * attacker, BattleHex _dest, 
		const CStack * _attacked, bool _catapult = false, int _catapultDmg = 0); 
};

/// This class manages a spell effect animation
class CSpellEffectAnimation : public CBattleAnimation
{
private:
	ui32 effect;
	BattleHex destTile;
	std::string	customAnim;
	int	x, y, dx, dy;
	bool Vflip;
public:
	bool init();
	void nextFrame();
	void endAnim();

	CSpellEffectAnimation(CBattleInterface * _owner, ui32 _effect, BattleHex _destTile, int _dx = 0, int _dy = 0, bool _Vflip = false);
	CSpellEffectAnimation(CBattleInterface * _owner, std::string _customAnim, int _x, int _y, int _dx = 0, int _dy = 0, bool _Vflip = false);
};