/*
 * IBattleInfoCallback.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
 *
 */

#pragma once

#include "GameConstants.h"
#include "BattleHex.h"

#include <vcmi/Entity.h>

#define RETURN_IF_NOT_BATTLE(...) do { if(!duringBattle()) {logGlobal->error("%s called when no battle!", __FUNCTION__); return __VA_ARGS__; } } while (false)

VCMI_LIB_NAMESPACE_BEGIN

struct CObstacleInstance;
class BattleField;
class IBattleInfo;

namespace battle
{
	class IUnitInfo;
	class Unit;
	using Units = std::vector<const Unit *>;
	using UnitFilter = std::function<bool(const Unit *)>;
}

struct DamageRange
{
	int64_t min = 0;
	int64_t max = 0;
};

struct DamageEstimation
{
	DamageRange damage;
	DamageRange kills;
};

#if SCRIPTING_ENABLED
namespace scripting
{
	class Pool;
}
#endif

class DLL_LINKAGE IBattleInfoCallback : public IConstBonusProvider
{
public:
#if SCRIPTING_ENABLED
	virtual scripting::Pool * getContextPool() const = 0;
#endif
	virtual ~IBattleInfoCallback() = default;

	virtual const IBattleInfo * getBattle() const = 0;
	virtual std::optional<PlayerColor> getPlayerID() const = 0;

	virtual TerrainId battleTerrainType() const = 0;
	virtual BattleField battleGetBattlefieldType() const = 0;

	///return none if battle is ongoing; otherwise the victorious side (0/1) or 2 if it is a draw
	virtual std::optional<int> battleIsFinished() const = 0;

	virtual si8 battleTacticDist() const = 0; //returns tactic distance in current tactics phase; 0 if not in tactics phase
	virtual si8 battleGetTacticsSide() const = 0; //returns which side is in tactics phase, undefined if none (?)

	virtual uint32_t battleNextUnitId() const = 0;

	virtual battle::Units battleGetUnitsIf(const battle::UnitFilter & predicate) const = 0;

	virtual const battle::Unit * battleGetUnitByID(uint32_t ID) const = 0;
	virtual const battle::Unit * battleGetUnitByPos(BattleHex pos, bool onlyAlive = true) const = 0;

	virtual const battle::Unit * battleActiveUnit() const = 0;

	//blocking obstacles makes tile inaccessible, others cause special effects (like Land Mines, Moat, Quicksands)
	virtual std::vector<std::shared_ptr<const CObstacleInstance>> battleGetAllObstaclesOnPos(BattleHex tile, bool onlyBlocking = true) const = 0;
	virtual std::vector<std::shared_ptr<const CObstacleInstance>> getAllAffectedObstaclesByStack(const battle::Unit * unit, const std::set<BattleHex> & passed) const = 0;
};



VCMI_LIB_NAMESPACE_END