/* This file is part of the Spring engine (GPL v2 or later), see LICENSE.html */

/* heavily based on CobInstance.h */

#ifndef UNIT_SCRIPT_H
#define UNIT_SCRIPT_H

#include <string>
#include <vector>
#include <list>

#include "System/Object.h"
#include "Rendering/Models/3DModel.h"


class CUnit;
class CPlasmaRepulser;


class CUnitScript : public CObject
{
public:
	enum AnimType {ANone = -1, ATurn = 0, ASpin = 1, AMove = 2};

	struct IAnimListener {
		virtual ~IAnimListener() {}
		virtual void AnimFinished(AnimType type, int piece, int axis) = 0;
	};

public:
	static const int UNIT_VAR_COUNT   = 8;
	static const int TEAM_VAR_COUNT   = 64;
	static const int ALLY_VAR_COUNT   = 64;
	static const int GLOBAL_VAR_COUNT = 4096;

	static const int UNIT_VAR_START   = 1024;
	static const int TEAM_VAR_START   = 2048;
	static const int ALLY_VAR_START   = 3072;
	static const int GLOBAL_VAR_START = 4096;

	static const int UNIT_VAR_END   = UNIT_VAR_START   + UNIT_VAR_COUNT   - 1;
	static const int TEAM_VAR_END   = TEAM_VAR_START   + TEAM_VAR_COUNT   - 1;
	static const int ALLY_VAR_END   = ALLY_VAR_START   + ALLY_VAR_COUNT   - 1;
	static const int GLOBAL_VAR_END = GLOBAL_VAR_START + GLOBAL_VAR_COUNT - 1;

	static void InitVars(int numTeams, int numAllyTeams);

public:
	static const int* GetTeamVars(int team) { return &teamVars[team][0]; }
	static const int* GetAllyVars(int ally) { return &allyVars[ally][0]; }
	static const int* GetGlobalVars()       { return globalVars; }

	const int* GetUnitVars() const { return unitVars; }
protected:
	static std::vector< std::vector<int> > teamVars;
	static std::vector< std::vector<int> > allyVars;
	static int globalVars[GLOBAL_VAR_COUNT];

	int unitVars[UNIT_VAR_COUNT];

protected:
	CUnit* unit;
	bool yardOpen;
	bool busy;

	struct AnimInfo {
		AnimType type;
		int axis;
		int piece;
		float speed;
		float dest;     // means final position when turning or moving, final speed when spinning
		float accel;    // used for spinning, can be negative
		bool done;
		std::list<IAnimListener*> listeners;
	};

	std::list<AnimInfo*> anims[AMove + 1];

	bool hasSetSFXOccupy;
	bool hasRockUnit;
	bool hasStartBuilding;

	void UnblockAll(AnimInfo* anim);

	bool MoveToward(float& cur, float dest, float speed);
	bool TurnToward(float& cur, float dest, float speed);
	bool DoSpin(float& cur, float dest, float& speed, float accel, int divisor);

	std::list<AnimInfo*>::iterator FindAnim(AnimType anim, int piece, int axis);
	void RemoveAnim(AnimType type, const std::list<AnimInfo*>::iterator& animInfoIt);
	void AddAnim(AnimType type, int piece, int axis, float speed, float dest, float accel);

	virtual void ShowScriptError(const std::string& msg) = 0;

public:
	// subclass is responsible for populating this with script pieces
	const std::vector<LocalModelPiece*>& pieces;

	bool PieceExists(unsigned int scriptPieceNum) const {
		// NOTE: there can be NULL pieces present from the remapping in CobInstance
		return ((scriptPieceNum < pieces.size()) && (pieces[scriptPieceNum] != NULL));
	}

	LocalModelPiece* GetScriptLocalModelPiece(unsigned int scriptPieceNum) const {
		assert(PieceExists(scriptPieceNum));
		return pieces[scriptPieceNum];
	}

	int ScriptToModel(int scriptPieceNum) const;
	int ModelToScript(int lmodelPieceNum) const;

#define SCRIPT_TO_LOCALPIECE_FUNC(x, y, z, w)                          \
	x y(int scriptPieceNum) const {                                    \
		if (!PieceExists(scriptPieceNum))                              \
			return w;                                                  \
		LocalModelPiece* p = GetScriptLocalModelPiece(scriptPieceNum); \
		return (p->z());                                               \
	}

	SCRIPT_TO_LOCALPIECE_FUNC(float3,     GetPiecePos,       GetAbsolutePos,      float3(0.0f,0.0f,0.0f))
	SCRIPT_TO_LOCALPIECE_FUNC(CMatrix44f, GetPieceMatrix,    GetModelSpaceMatrix,           CMatrix44f())
	SCRIPT_TO_LOCALPIECE_FUNC(float3,     GetPieceDirection, GetDirection,        float3(1.0f,1.0f,1.0f))

	bool GetEmitDirPos(int scriptPieceNum, float3& pos, float3& dir) const {
		if (!PieceExists(scriptPieceNum))
			return true;

		LocalModelPiece* p = GetScriptLocalModelPiece(scriptPieceNum);
		return (p->GetEmitDirPos(pos, dir));
	}

public:
	CUnitScript(CUnit* unit, const std::vector<LocalModelPiece*>& pieces);
	virtual ~CUnitScript();

	bool IsBusy() const { return busy; }

	      CUnit* GetUnit()       { return unit; }
	const CUnit* GetUnit() const { return unit; }

	bool Tick(int deltaTime);
	void TickAnims(int deltaTime, AnimType type, std::list< std::list<AnimInfo*>::iterator >& doneAnims);

	// animation, used by CCobThread
	void Spin(int piece, int axis, float speed, float accel);
	void StopSpin(int piece, int axis, float decel);
	void Turn(int piece, int axis, float speed, float destination);
	void Move(int piece, int axis, float speed, float destination);
	void MoveNow(int piece, int axis, float destination);
	void TurnNow(int piece, int axis, float destination);

	bool AddAnimListener(AnimType type, int piece, int axis, IAnimListener* listener);

	// misc, used by CCobThread and callouts for Lua unitscripts
	void SetVisibility(int piece, bool visible);
	void EmitSfx(int type, int piece);
	void AttachUnit(int piece, int unit);
	void DropUnit(int unit);
	void Explode(int piece, int flags);
	void Shatter(int piece, const float3& pos, const float3& speed);
	void ShowFlare(int piece);
	int GetUnitVal(int val, int p1, int p2, int p3, int p4);
	void SetUnitVal(int val, int param);

	bool IsInAnimation(AnimType type, int piece, int axis) {
		return (FindAnim(type, piece, axis) != anims[type].end());
	}
	bool HaveAnimations() const {
		return (!anims[ATurn].empty() || !anims[ASpin].empty() || !anims[AMove].empty());
	}
	inline bool HaveListeners() const;

	// checks for callin existence
	bool HasSetSFXOccupy () const { return hasSetSFXOccupy; }
	bool HasRockUnit     () const { return hasRockUnit; }
	bool HasStartBuilding() const { return hasStartBuilding; }
	virtual bool HasBlockShot   (int weaponNum) const { return false; }
	virtual bool HasTargetWeight(int weaponNum) const { return false; }

	// callins, called throughout sim
	virtual void RawCall(int functionId) = 0;
	virtual void Create() = 0;
	// Killed must cause unit->deathScriptFinished and unit->delayedWreckLevel to be set!
	virtual void Killed() = 0;
	virtual void WindChanged(float heading, float speed) = 0;
	virtual void ExtractionRateChanged(float speed) = 0;
	virtual void RockUnit(const float3& rockDir) = 0;
	virtual void HitByWeapon(const float3& hitDir, int weaponDefId, float& inout_damage) = 0;
	virtual void SetSFXOccupy(int curTerrainType) = 0;
	// doubles as QueryLandingPadCount and QueryLandingPad
	// in COB, the first one determines the number of arguments to the second one
	// in Lua, we can just count the number of return values
	virtual void QueryLandingPads(std::vector<int>& out_pieces) = 0;
	virtual void BeginTransport(const CUnit* unit) = 0;
	virtual int  QueryTransport(const CUnit* unit) = 0; // returns piece
	virtual void TransportPickup(const CUnit* unit) = 0;
	virtual void TransportDrop(const CUnit* unit, const float3& pos) = 0;
	virtual void StartBuilding(float heading, float pitch) = 0;
	virtual int  QueryNanoPiece() = 0; // returns piece
	virtual int  QueryBuildInfo() = 0; // returns piece

	virtual void Destroy() = 0;
	virtual void StartMoving(bool reversing) = 0;
	virtual void StopMoving() = 0;
	virtual void StartUnload() = 0;
	virtual void EndTransport() = 0;
	virtual void StartBuilding() = 0;
	virtual void StopBuilding() = 0;
	virtual void Falling() = 0;
	virtual void Landed() = 0;
	virtual void Activate() = 0;
	virtual void Deactivate() = 0;
	virtual void MoveRate(int curRate) = 0;
	virtual void FireWeapon(int weaponNum) = 0;
	virtual void EndBurst(int weaponNum) = 0;

	// weapon callins
	virtual int   QueryWeapon(int weaponNum) = 0; // returns piece, former QueryPrimary
	virtual void  AimWeapon(int weaponNum, float heading, float pitch) = 0;
	virtual void  AimShieldWeapon(CPlasmaRepulser* weapon) = 0;
	virtual int   AimFromWeapon(int weaponNum) = 0; // returns piece, former AimFromPrimary
	virtual void  Shot(int weaponNum) = 0;
	virtual bool  BlockShot(int weaponNum, const CUnit* targetUnit, bool userTarget) = 0; // returns whether shot should be blocked
	virtual float TargetWeight(int weaponNum, const CUnit* targetUnit) = 0; // returns target weight
};

inline bool CUnitScript::HaveListeners() const {
	for (int animType = ATurn; animType <= AMove; animType++) {
		for (std::list<AnimInfo *>::const_iterator i = anims[animType].begin(); i != anims[animType].end(); ++i) {
			if (!(*i)->listeners.empty()) {
				return true;
			}
		}
	}
	return false;
}

#endif // UNIT_SCRIPT_H