/*
 * Client.cpp, 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
 *
 */
#include "StdInc.h"
#include "Global.h"
#include "Client.h"

#include "CPlayerInterface.h"
#include "PlayerLocalState.h"
#include "CServerHandler.h"
#include "ClientNetPackVisitors.h"
#include "adventureMap/AdventureMapInterface.h"
#include "battle/BattleInterface.h"
#include "GameEngine.h"
#include "GameInstance.h"
#include "gui/WindowHandler.h"
#include "mapView/mapHandler.h"

#include "../lib/CConfigHandler.h"
#include "../lib/GameLibrary.h"
#include "../lib/battle/BattleInfo.h"
#include "../lib/battle/CPlayerBattleCallback.h"
#include "../lib/callback/CCallback.h"
#include "../lib/callback/CDynLibHandler.h"
#include "../lib/callback/CGlobalAI.h"
#include "../lib/callback/IGameInfoCallback.h"
#include "../lib/filesystem/Filesystem.h"
#include "../lib/gameState/CGameState.h"
#include "../lib/CPlayerState.h"
#include "../lib/CThreadHelper.h"
#include "../lib/VCMIDirs.h"
#include "../lib/UnlockGuard.h"
#include "../lib/mapObjects/army/CArmedInstance.h"
#include "../lib/mapping/CMapService.h"
#include "../lib/pathfinder/CGPathNode.h"
#include "../lib/serializer/GameConnection.h"

#include <memory>
#include <vcmi/events/EventBus.h>

#if SCRIPTING_ENABLED
#include "../lib/ScriptHandler.h"
#endif

#ifdef VCMI_ANDROID
#include "lib/CAndroidVMHelper.h"
#endif

CPlayerEnvironment::CPlayerEnvironment(PlayerColor player_, CClient * cl_, std::shared_ptr<CCallback> mainCallback_)
	: player(player_),
	cl(cl_),
	mainCallback(mainCallback_)
{

}

const Services * CPlayerEnvironment::services() const
{
	return LIBRARY;
}

vstd::CLoggerBase * CPlayerEnvironment::logger() const
{
	return logGlobal;
}

events::EventBus * CPlayerEnvironment::eventBus() const
{
	return cl->eventBus();//always get actual value
}

const CPlayerEnvironment::BattleCb * CPlayerEnvironment::battle(const BattleID & battleID) const
{
	return mainCallback->getBattle(battleID).get();
}

const CPlayerEnvironment::GameCb * CPlayerEnvironment::game() const
{
	return mainCallback.get();
}

CClient::CClient()
{
	waitingRequest.clear();
}

CClient::~CClient() = default;

IGameInfoCallback & CClient::gameInfo()
{
	return *gamestate;
}

const Services * CClient::services() const
{
	return LIBRARY; //todo: this should be LIBRARY
}

const CClient::BattleCb * CClient::battle(const BattleID & battleID) const
{
	return nullptr; //todo?
}

const CClient::GameCb * CClient::game() const
{
	return gamestate.get();
}

vstd::CLoggerBase * CClient::logger() const
{
	return logGlobal;
}

events::EventBus * CClient::eventBus() const
{
	return clientEventBus.get();
}

void CClient::newGame(std::shared_ptr<CGameState> initializedGameState)
{
	GAME->server().th->update();
	assert(initializedGameState);
	gamestate = initializedGameState;
	gamestate->preInit(LIBRARY);
	logNetwork->trace("\tCreating gamestate: %i", GAME->server().th->getDiff());

	initMapHandler();
	reinitScripting();
	initPlayerEnvironments();
	initPlayerInterfaces();
}

void CClient::loadGame(std::shared_ptr<CGameState> initializedGameState)
{
	logNetwork->info("Loading procedure started!");

	logNetwork->info("Game state was transferred over network, loading.");
	gamestate = initializedGameState;
	gamestate->preInit(LIBRARY);
	gamestate->updateOnLoad(*GAME->server().si);
	logNetwork->info("Game loaded, initialize interfaces.");

	initMapHandler();
	reinitScripting();
	initPlayerEnvironments();
	initPlayerInterfaces();
}

void CClient::endNetwork()
{
	GAME->map().endNetwork();

	if (CPlayerInterface::battleInt)
		CPlayerInterface::battleInt->endNetwork();

	for(auto & i : playerint)
	{
		auto interface = std::dynamic_pointer_cast<CPlayerInterface>(i.second);
		if (interface)
			interface->endNetwork();
	}
}

void CClient::finishGameplay()
{
	waitingRequest.requestTermination();

	//suggest interfaces to finish their stuff (AI should interrupt any bg working threads)
	for(auto & i : playerint)
		i.second->finish();
}

void CClient::endGame()
{
#if SCRIPTING_ENABLED
	clientScripts.reset();
#endif

	logNetwork->info("Ending current game!");
	removeGUI();

	GAME->setMapInstance(nullptr);

	logNetwork->info("Deleted mapHandler and gameState.");

	CPlayerInterface::battleInt.reset();
	playerint.clear();
	battleints.clear();
	battleCallbacks.clear();
	playerEnvironments.clear();

	//FIXME: gamestate->currentBattles.clear() will use gamestate. So it shoule be callded before gamestate.reset()
	gamestate->currentBattles.clear();
	gamestate.reset();

	logNetwork->info("Deleted playerInts.");
	logNetwork->info("Client stopped.");
}

void CClient::initMapHandler()
{
	// TODO: CMapHandler initialization can probably go somewhere else
	// It's can't be before initialization of interfaces
	// During loading CPlayerInterface from serialized state it's depend on MH
	if(!settings["session"]["headless"].Bool())
	{
		GAME->setMapInstance(std::make_unique<CMapHandler>(&gameState().getMap()));
		logNetwork->trace("Creating mapHandler: %d ms", GAME->server().th->getDiff());
	}
}

void CClient::initPlayerEnvironments()
{
	playerEnvironments.clear();

	auto allPlayers = GAME->server().getAllClientPlayers(GAME->server().logicConnection->connectionID);
	bool hasHumanPlayer = false;
	for(auto & color : allPlayers)
	{
		logNetwork->info("Preparing environment for player %s", color.toString());
		playerEnvironments[color] = std::make_shared<CPlayerEnvironment>(color, this, std::make_shared<CCallback>(gamestate, color, this));
		
		if(color.isValidPlayer() && !hasHumanPlayer && gameState().players.at(color).isHuman())
			hasHumanPlayer = true;
	}

	if(!hasHumanPlayer && !settings["session"]["headless"].Bool())
	{
		Settings session = settings.write["session"];
		session["spectate"].Bool() = true;
		session["spectate-skip-battle-result"].Bool() = true;
		session["spectate-ignore-hero"].Bool() = true;
	}
	
	if(settings["session"]["spectate"].Bool())
	{
		playerEnvironments[PlayerColor::SPECTATOR] = std::make_shared<CPlayerEnvironment>(PlayerColor::SPECTATOR, this, std::make_shared<CCallback>(gamestate, std::nullopt, this));
	}
}

void CClient::initPlayerInterfaces()
{
	for(const auto & playerInfo : gameState().getStartInfo()->playerInfos)
	{
		PlayerColor color = playerInfo.first;
		if(!vstd::contains(GAME->server().getAllClientPlayers(GAME->server().logicConnection->connectionID), color))
			continue;

		if(!vstd::contains(playerint, color))
		{
			logNetwork->info("Preparing interface for player %s", color.toString());
			if(playerInfo.second.isControlledByAI() || settings["session"]["onlyai"].Bool())
			{
				bool alliedToHuman = false;
				for(const auto & allyInfo : gameState().getStartInfo()->playerInfos)
					if (gameState().getPlayerTeam(allyInfo.first) == gameState().getPlayerTeam(playerInfo.first) && allyInfo.second.isControlledByHuman())
						alliedToHuman = true;

				auto AiToGive = aiNameForPlayer(playerInfo.second, false, alliedToHuman);
				logNetwork->info("Player %s will be lead by %s", color.toString(), AiToGive);
				installNewPlayerInterface(CDynLibHandler::getNewAI(AiToGive), color);
			}
			else
			{
				logNetwork->info("Player %s will be lead by human", color.toString());
				installNewPlayerInterface(std::make_shared<CPlayerInterface>(color), color);
			}

			if(!advInterfaceReadySent.contains(color))
			{
				advInterfaceReadySent.insert(color);
				AdvInterfaceReady air;
				sendRequest(air, color, /* waitTillRealize = */ false);
			}
		}
	}

	if(settings["session"]["spectate"].Bool())
	{
		installNewPlayerInterface(std::make_shared<CPlayerInterface>(PlayerColor::SPECTATOR), PlayerColor::SPECTATOR, true);
	}

	if(GAME->server().getAllClientPlayers(GAME->server().logicConnection->connectionID).count(PlayerColor::NEUTRAL))
		installNewBattleInterface(CDynLibHandler::getNewBattleAI(settings["ai"]["combatNeutralAI"].String()), PlayerColor::NEUTRAL);

	logNetwork->trace("Initialized player interfaces %d ms", GAME->server().th->getDiff());
}

std::string CClient::aiNameForPlayer(const PlayerSettings & ps, bool battleAI, bool alliedToHuman) const
{
	if(ps.name.size())
	{
		const boost::filesystem::path aiPath = VCMIDirs::get().fullLibraryPath("AI", ps.name);
		if(boost::filesystem::exists(aiPath))
			return ps.name;
	}

	return aiNameForPlayer(battleAI, alliedToHuman);
}

std::string CClient::aiNameForPlayer(bool battleAI, bool alliedToHuman) const
{
	const int sensibleAILimit = settings["session"]["oneGoodAI"].Bool() ? 1 : PlayerColor::PLAYER_LIMIT_I;
	std::string goodAdventureAI = alliedToHuman ? settings["ai"]["adventureAlliedAI"].String() : settings["ai"]["adventureEnemyAI"].String();
	std::string goodBattleAI = settings["ai"]["combatNeutralAI"].String();
	std::string goodAI = battleAI ? goodBattleAI : goodAdventureAI;
	std::string badAI = battleAI ? "StupidAI" : "EmptyAI";

	//TODO what about human players
	if(battleints.size() >= sensibleAILimit)
		return badAI;

	return goodAI;
}

void CClient::installNewPlayerInterface(std::shared_ptr<CGameInterface> gameInterface, PlayerColor color, bool battlecb)
{
	playerint[color] = gameInterface;

	logGlobal->trace("\tInitializing the interface for player %s", color.toString());
	auto cb = std::make_shared<CCallback>(gamestate, color, this);
	battleCallbacks[color] = cb;
	gameInterface->initGameInterface(playerEnvironments.at(color), cb);

	installNewBattleInterface(gameInterface, color, battlecb);
}

void CClient::installNewBattleInterface(std::shared_ptr<CBattleGameInterface> battleInterface, PlayerColor color, bool needCallback)
{
	battleints[color] = battleInterface;

	if(needCallback)
	{
		logGlobal->trace("\tInitializing the battle interface for player %s", color.toString());
		auto cbc = std::make_shared<CBattleCallback>(color, this);
		battleCallbacks[color] = cbc;
		battleInterface->initBattleInterface(playerEnvironments.at(color), cbc);
	}
}

void CClient::handlePack(CPackForClient & pack)
{
	ApplyClientNetPackVisitor afterVisitor(*this, gameState());
	ApplyFirstClientNetPackVisitor beforeVisitor(*this, gameState());

	pack.visit(beforeVisitor);
	logNetwork->trace("\tMade first apply on cl: %s", typeid(pack).name());
	{
		std::unique_lock lock(CGameState::mutex);
		gameState().apply(pack);
	}
	logNetwork->trace("\tApplied on gs: %s", typeid(pack).name());
	pack.visit(afterVisitor);
	logNetwork->trace("\tMade second apply on cl: %s", typeid(pack).name());
}

std::optional<BattleAction> CClient::makeSurrenderRetreatDecision(PlayerColor player, const BattleID & battleID, const BattleStateInfoForRetreat & battleState)
{
	return playerint[player]->makeSurrenderRetreatDecision(battleID, battleState);
}

int CClient::sendRequest(const CPackForServer & request, PlayerColor player, bool waitTillRealize)
{
	ui32 requestID = requestCounter++;
	logNetwork->trace("Sending a request \"%s\". It'll have an ID=%d.", typeid(request).name(), requestID);

	waitingRequest.pushBack(requestID);
	request.requestID = requestID;
	request.player = player;
	GAME->server().sendGamePack(request);
	if(vstd::contains(playerint, player))
		playerint[player]->requestSent(&request, requestID);

	if(waitTillRealize)
	{
		logGlobal->trace("We'll wait till request %d is answered.\n", requestID);
		auto gsUnlocker = vstd::makeUnlockSharedGuard(CGameState::mutex);
		waitingRequest.waitWhileContains(requestID);
	}

	return requestID;
}

void CClient::battleStarted(const BattleID & battleID)
{
	const BattleInfo * info = gameState().getBattle(battleID);

	std::shared_ptr<CPlayerInterface> att;
	std::shared_ptr<CPlayerInterface> def;
	const auto & leftSide = info->getSide(BattleSide::LEFT_SIDE);
	const auto & rightSide = info->getSide(BattleSide::RIGHT_SIDE);

	for(auto & battleCb : battleCallbacks)
	{
		if(!battleCb.first.isValidPlayer() || battleCb.first == leftSide.color || battleCb.first == rightSide.color)
			battleCb.second->onBattleStarted(info);
	}

	//If quick combat is not, do not prepare interfaces for battleint
	auto callBattleStart = [&](PlayerColor color, BattleSide side)
	{
		if(vstd::contains(battleints, color))
			battleints[color]->battleStart(info->battleID, leftSide.getArmy(), rightSide.getArmy(), info->tile, leftSide.getHero(), rightSide.getHero(), side, info->replayAllowed);
	};
	
	callBattleStart(leftSide.color, BattleSide::LEFT_SIDE);
	callBattleStart(rightSide.color, BattleSide::RIGHT_SIDE);
	callBattleStart(PlayerColor::UNFLAGGABLE, BattleSide::RIGHT_SIDE);
	if(settings["session"]["spectate"].Bool() && !settings["session"]["spectate-skip-battle"].Bool())
		callBattleStart(PlayerColor::SPECTATOR, BattleSide::RIGHT_SIDE);
	
	if(vstd::contains(playerint, leftSide.color) && playerint[leftSide.color]->human)
		att = std::dynamic_pointer_cast<CPlayerInterface>(playerint[leftSide.color]);

	if(vstd::contains(playerint, rightSide.color) && playerint[rightSide.color]->human)
		def = std::dynamic_pointer_cast<CPlayerInterface>(playerint[rightSide.color]);
	
	//Remove player interfaces for auto battle (quickCombat option)
	if((att && att->isAutoFightOn) || (def && def->isAutoFightOn))
	{
		auto endTacticPhaseIfEligible = [info](const CPlayerInterface * interface)
		{
			if (interface->cb->getBattle(info->battleID)->battleGetTacticDist())
			{
				auto side = interface->cb->getBattle(info->battleID)->playerToSide(interface->playerID);

				if(interface->playerID == info->getSide(info->tacticsSide).color)
				{
					auto action = BattleAction::makeEndOFTacticPhase(side);
					interface->cb->battleMakeTacticAction(info->battleID, action);
				}
			}
		};

		if(att && att->isAutoFightOn)
			endTacticPhaseIfEligible(att.get());
		else // def && def->isAutoFightOn
			endTacticPhaseIfEligible(def.get());

		att.reset();
		def.reset();
	}

	if(!settings["session"]["headless"].Bool())
	{
		if(att || def)
		{
			CPlayerInterface::battleInt = std::make_shared<BattleInterface>(info->getBattleID(), leftSide.getArmy(), rightSide.getArmy(), leftSide.getHero(), rightSide.getHero(), att, def);
		}
		else if(settings["session"]["spectate"].Bool() && !settings["session"]["spectate-skip-battle"].Bool())
		{
			//TODO: This certainly need improvement
			auto spectratorInt = std::dynamic_pointer_cast<CPlayerInterface>(playerint[PlayerColor::SPECTATOR]);
			spectratorInt->cb->onBattleStarted(info);
			CPlayerInterface::battleInt = std::make_shared<BattleInterface>(info->getBattleID(), leftSide.getArmy(), rightSide.getArmy(), leftSide.getHero(), rightSide.getHero(), att, def, spectratorInt);
		}
	}

	if(info->tacticDistance)
	{
		auto tacticianColor = info->getSide(info->tacticsSide).color;

		if (vstd::contains(battleints, tacticianColor))
			battleints[tacticianColor]->yourTacticPhase(info->battleID, info->tacticDistance);
	}
}

void CClient::battleFinished(const BattleID & battleID)
{
	for(auto side : { BattleSide::ATTACKER, BattleSide::DEFENDER })
	{
		if(battleCallbacks.count(gameState().getBattle(battleID)->getSide(side).color))
			battleCallbacks[gameState().getBattle(battleID)->getSide(side).color]->onBattleEnded(battleID);
	}

	if(settings["session"]["spectate"].Bool() && !settings["session"]["spectate-skip-battle"].Bool())
		battleCallbacks[PlayerColor::SPECTATOR]->onBattleEnded(battleID);
}

void CClient::startPlayerBattleAction(const BattleID & battleID, PlayerColor color)
{
	if (battleints.count(color) == 0)
		return; // not our combat in MP

	auto battleint = battleints.at(color);

	if (!battleint->human)
	{
		// we want to avoid locking gamestate and causing UI to freeze while AI is making turn
		auto unlockInterface = vstd::makeUnlockGuard(ENGINE->interfaceMutex);
		battleint->activeStack(battleID, gameState().getBattle(battleID)->battleGetStackByID(gameState().getBattle(battleID)->activeStack, false));
	}
	else
	{
		battleint->activeStack(battleID, gameState().getBattle(battleID)->battleGetStackByID(gameState().getBattle(battleID)->activeStack, false));
	}
}

void CClient::reinitScripting()
{
	clientEventBus = std::make_unique<events::EventBus>();
#if SCRIPTING_ENABLED
	clientScripts.reset(new scripting::PoolImpl(this));
#endif
}

void CClient::removeGUI() const
{
	// CClient::endGame
	ENGINE->windows().clear();
	adventureInt.reset();
	logGlobal->info("Removed GUI.");

	GAME->setInterfaceInstance(nullptr);
}

void CClient::registerBattleInterface(std::shared_ptr<IBattleEventsReceiver> battleEvents, PlayerColor color)
{
	additionalBattleInts[color].push_back(battleEvents);
}

void CClient::unregisterBattleInterface(std::shared_ptr<IBattleEventsReceiver> battleEvents, PlayerColor color)
{
	additionalBattleInts[color] -= battleEvents;
}