/*
 * CMapGenerator.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 "CMapGenerator.h"

#include "../mapping/CMap.h"
#include "../VCMI_Lib.h"
#include "../CGeneralTextHandler.h"
#include "../mapping/CMapEditManager.h"
#include "../CTownHandler.h"
#include "../StringConstants.h"
#include "../filesystem/Filesystem.h"
#include "CZonePlacer.h"
#include "../mapObjects/CObjectClassesHandler.h"
#include "TileInfo.h"
#include "Zone.h"
#include "Functions.h"
#include "RmgMap.h"
#include "ObjectManager.h"
#include "TreasurePlacer.h"
#include "RoadPlacer.h"

VCMI_LIB_NAMESPACE_BEGIN

CMapGenerator::CMapGenerator(CMapGenOptions& mapGenOptions, int RandomSeed) :
	mapGenOptions(mapGenOptions), randomSeed(RandomSeed),
	prisonsRemaining(0), monolithIndex(0)
{
	loadConfig();
	rand.setSeed(this->randomSeed);
	mapGenOptions.finalize(rand);
	map = std::make_unique<RmgMap>(mapGenOptions);
}

int CMapGenerator::getRandomSeed() const
{
	return randomSeed;
}

void CMapGenerator::loadConfig()
{
	static const ResourceID path("config/randomMap.json");
	JsonNode randomMapJson(path);

	config.shipyardGuard = randomMapJson["waterZone"]["shipyard"]["value"].Integer();
	for(auto & treasure : randomMapJson["waterZone"]["treasure"].Vector())
	{
		config.waterTreasure.emplace_back(treasure["min"].Integer(), treasure["max"].Integer(), treasure["density"].Integer());
	}
	config.mineExtraResources = randomMapJson["mines"]["extraResourcesLimit"].Integer();
	config.minGuardStrength = randomMapJson["minGuardStrength"].Integer();
	config.defaultRoadType = randomMapJson["defaultRoadType"].String();
	config.secondaryRoadType = randomMapJson["secondaryRoadType"].String();
	config.treasureValueLimit = randomMapJson["treasureValueLimit"].Integer();
	for(auto & i : randomMapJson["prisons"]["experience"].Vector())
		config.prisonExperience.push_back(i.Integer());
	for(auto & i : randomMapJson["prisons"]["value"].Vector())
		config.prisonValues.push_back(i.Integer());
	for(auto & i : randomMapJson["scrolls"]["value"].Vector())
		config.scrollValues.push_back(i.Integer());
	for(auto & i : randomMapJson["pandoras"]["creaturesValue"].Vector())
		config.pandoraCreatureValues.push_back(i.Integer());
	for(auto & i : randomMapJson["quests"]["value"].Vector())
		config.questValues.push_back(i.Integer());
	for(auto & i : randomMapJson["quests"]["rewardValue"].Vector())
		config.questRewardValues.push_back(i.Integer());
	config.pandoraMultiplierGold = randomMapJson["pandoras"]["valueMultiplierGold"].Integer();
	config.pandoraMultiplierExperience = randomMapJson["pandoras"]["valueMultiplierExperience"].Integer();
	config.pandoraMultiplierSpells = randomMapJson["pandoras"]["valueMultiplierSpells"].Integer();
	config.pandoraSpellSchool = randomMapJson["pandoras"]["valueSpellSchool"].Integer();
	config.pandoraSpell60 = randomMapJson["pandoras"]["valueSpell60"].Integer();
	//override config with game options
	if(!mapGenOptions.isRoadEnabled(config.secondaryRoadType))
		config.secondaryRoadType = "";
	if(!mapGenOptions.isRoadEnabled(config.defaultRoadType))
		config.defaultRoadType = config.secondaryRoadType;
}

const CMapGenerator::Config & CMapGenerator::getConfig() const
{
	return config;
}

//must be instantiated in .cpp file for access to complete types of all member fields
CMapGenerator::~CMapGenerator() = default;

const CMapGenOptions& CMapGenerator::getMapGenOptions() const
{
	return mapGenOptions;
}

void CMapGenerator::initPrisonsRemaining()
{
	prisonsRemaining = 0;
	for (auto isAllowed : map->map().allowedHeroes)
	{
		if (isAllowed)
			prisonsRemaining++;
	}
	prisonsRemaining = std::max<int> (0, prisonsRemaining - 16 * mapGenOptions.getPlayerCount()); //so at least 16 heroes will be available for every player
}

void CMapGenerator::initQuestArtsRemaining()
{
	for (auto art : VLC->arth->objects)
	{
		if (art->aClass == CArtifact::ART_TREASURE && VLC->arth->legalArtifact(art->getId()) && art->constituentOf.empty()) //don't use parts of combined artifacts
			questArtifacts.push_back(art->getId());
	}
}

std::unique_ptr<CMap> CMapGenerator::generate()
{
	Load::Progress::reset();
	Load::Progress::setupStepsTill(5, 30);
	try
	{
		addHeaderInfo();
		map->initTiles(*this);
		Load::Progress::step();
		initPrisonsRemaining();
		initQuestArtsRemaining();
		genZones();
		Load::Progress::step();
		map->map().calculateGuardingGreaturePositions(); //clear map so that all tiles are unguarded
		map->addModificators();
		Load::Progress::step(3);
		fillZones();
		//updated guarded tiles will be calculated in CGameState::initMapObjects()
		map->getZones().clear();
	}
	catch (rmgException &e)
	{
		logGlobal->error("Random map generation received exception: %s", e.what());
	}
	Load::Progress::finish();
	return std::move(map->mapInstance);
}

std::string CMapGenerator::getMapDescription() const
{
	assert(map);

	const std::string waterContentStr[3] = { "none", "normal", "islands" };
	const std::string monsterStrengthStr[3] = { "weak", "normal", "strong" };

	int monsterStrengthIndex = mapGenOptions.getMonsterStrength() - EMonsterStrength::GLOBAL_WEAK; //does not start from 0
	const auto * mapTemplate = mapGenOptions.getMapTemplate();

	if(!mapTemplate)
		throw rmgException("Map template for Random Map Generator is not found. Could not start the game.");

    std::stringstream ss;
    ss << boost::str(boost::format(std::string("Map created by the Random Map Generator.\nTemplate was %s, Random seed was %d, size %dx%d") +
        ", levels %d, players %d, computers %d, water %s, monster %s, VCMI map") % mapTemplate->getName() %
		randomSeed % map->map().width % map->map().height % static_cast<int>(map->map().levels()) % static_cast<int>(mapGenOptions.getPlayerCount()) %
		static_cast<int>(mapGenOptions.getCompOnlyPlayerCount()) % waterContentStr[mapGenOptions.getWaterContent()] %
		monsterStrengthStr[monsterStrengthIndex]);

	for(const auto & pair : mapGenOptions.getPlayersSettings())
	{
		const auto & pSettings = pair.second;
		if(pSettings.getPlayerType() == EPlayerType::HUMAN)
		{
			ss << ", " << GameConstants::PLAYER_COLOR_NAMES[pSettings.getColor().getNum()] << " is human";
		}
		if(pSettings.getStartingTown() != CMapGenOptions::CPlayerSettings::RANDOM_TOWN)
		{
			ss << ", " << GameConstants::PLAYER_COLOR_NAMES[pSettings.getColor().getNum()]
			   << " town choice is " << (*VLC->townh)[pSettings.getStartingTown()]->getNameTranslated();
		}
	}

	return ss.str();
}

void CMapGenerator::addPlayerInfo()
{
	// Calculate which team numbers exist

	enum ETeams {CPHUMAN = 0, CPUONLY = 1, AFTER_LAST = 2};
	std::array<std::list<int>, 2> teamNumbers;
	std::set<int> teamsTotal;

	int teamOffset = 0;
	int playerCount = 0;
	int teamCount = 0;

	for (int i = CPHUMAN; i < AFTER_LAST; ++i)
	{
		if (i == CPHUMAN)
		{
			playerCount = mapGenOptions.getPlayerCount();
			teamCount = mapGenOptions.getTeamCount();
		}
		else
		{
			playerCount = mapGenOptions.getCompOnlyPlayerCount();
			teamCount = mapGenOptions.getCompOnlyTeamCount();
		}

		if(playerCount == 0)
		{
			continue;
		}
		int playersPerTeam = playerCount / (teamCount == 0 ? playerCount : teamCount);
		int teamCountNorm = teamCount;
		if(teamCountNorm == 0)
		{
			teamCountNorm = playerCount;
		}
		for(int j = 0; j < teamCountNorm; ++j)
		{
			for(int k = 0; k < playersPerTeam; ++k)
			{
				teamNumbers[i].push_back(j + teamOffset);
			}
		}
		for(int j = 0; j < playerCount - teamCountNorm * playersPerTeam; ++j)
		{
			teamNumbers[i].push_back(j + teamOffset);
		}
		teamOffset += teamCountNorm;
	}

	// Team numbers are assigned randomly to every player
	//TODO: allow customize teams in rmg template
	for(const auto & pair : mapGenOptions.getPlayersSettings())
	{
		const auto & pSettings = pair.second;
		PlayerInfo player;
		player.canComputerPlay = true;
		int j = (pSettings.getPlayerType() == EPlayerType::COMP_ONLY) ? CPUONLY : CPHUMAN;
		if (j == CPHUMAN)
		{
			player.canHumanPlay = true;
		}

		if(pSettings.getTeam() != TeamID::NO_TEAM)
		{
			player.team = pSettings.getTeam();
		}
		else
		{
			if (teamNumbers[j].empty())
			{
				logGlobal->error("Not enough places in team for %s player", ((j == CPUONLY) ? "CPU" : "CPU or human"));
				assert (teamNumbers[j].size());
			}
			auto itTeam = RandomGeneratorUtil::nextItem(teamNumbers[j], rand);
			player.team = TeamID(*itTeam);
			teamNumbers[j].erase(itTeam);
		}
		teamsTotal.insert(player.team.getNum());
		map->map().players[pSettings.getColor().getNum()] = player;
	}

	map->map().howManyTeams = teamsTotal.size();
}

void CMapGenerator::genZones()
{
	CZonePlacer placer(*map);
	placer.placeZones(&rand);
	placer.assignZones(&rand);

	logGlobal->info("Zones generated successfully");
}

void CMapGenerator::createWaterTreasures()
{
	if (!getZoneWater())
		return;

	//add treasures on water
	for (const auto& treasureInfo : getConfig().waterTreasure)
	{
		getZoneWater()->addTreasureInfo(treasureInfo);
	}
}

void CMapGenerator::fillZones()
{
	findZonesForQuestArts();
	createWaterTreasures();

	logGlobal->info("Started filling zones");

	//we need info about all town types to evaluate dwellings and pandoras with creatures properly
	//place main town in the middle
	Load::Progress::setupStepsTill(map->getZones().size(), 50);
	for (const auto& it : map->getZones())
	{
		it.second->initFreeTiles();
		it.second->initModificators();
		Progress::Progress::step();
	}

	Load::Progress::setupStepsTill(map->getZones().size(), 240);
	std::vector<std::shared_ptr<Zone>> treasureZones;
	for (const auto& it : map->getZones())
	{
		it.second->processModificators();

		if (it.second->getType() == ETemplateZoneType::TREASURE)
			treasureZones.push_back(it.second);

		Progress::Progress::step();
	}

	//find place for Grail
	if (treasureZones.empty())
	{
		for (const auto& it : map->getZones())
			if (it.second->getType() != ETemplateZoneType::WATER)
				treasureZones.push_back(it.second);
	}
	auto grailZone = *RandomGeneratorUtil::nextItem(treasureZones, rand);

	map->map().grailPos = *RandomGeneratorUtil::nextItem(grailZone->freePaths().getTiles(), rand);

	logGlobal->info("Zones filled successfully");

	Load::Progress::set(250);
}

void CMapGenerator::findZonesForQuestArts()
{
	//we want to place arties in zones that were not yet filled (higher index)

	for (auto connection : mapGenOptions.getMapTemplate()->getConnections())
	{
		auto zoneA = map->getZones()[connection.getZoneA()];
		auto zoneB = map->getZones()[connection.getZoneB()];

		if (zoneA->getId() > zoneB->getId())
		{
			if(auto * m = zoneB->getModificator<TreasurePlacer>())
				m->setQuestArtZone(zoneA.get());
		}
		else if (zoneA->getId() < zoneB->getId())
		{
			if(auto * m = zoneA->getModificator<TreasurePlacer>())
				m->setQuestArtZone(zoneB.get());
		}
	}
}

void CMapGenerator::addHeaderInfo()
{
	map->map().version = EMapFormat::VCMI;
	map->map().width = mapGenOptions.getWidth();
	map->map().height = mapGenOptions.getHeight();
	map->map().twoLevel = mapGenOptions.getHasTwoLevels();
	map->map().name = VLC->generaltexth->allTexts[740];
	map->map().description = getMapDescription();
	map->map().difficulty = 1;
	addPlayerInfo();
}

int CMapGenerator::getNextMonlithIndex()
{
	while (true)
	{
		if (monolithIndex >= VLC->objtypeh->knownSubObjects(Obj::MONOLITH_TWO_WAY).size())
			throw rmgException(boost::to_string(boost::format("There is no Monolith Two Way with index %d available!") % monolithIndex));
		else
		{
			//Skip modded Monoliths which can't beplaced on every terrain
			auto templates = VLC->objtypeh->getHandlerFor(Obj::MONOLITH_TWO_WAY, monolithIndex)->getTemplates();
			if (templates.empty() || !templates[0]->canBePlacedAtAnyTerrain())
			{
				monolithIndex++;
			}
			else
			{
				return monolithIndex++;
			}
		}
	}
}

int CMapGenerator::getPrisonsRemaning() const
{
	return prisonsRemaining;
}

void CMapGenerator::decreasePrisonsRemaining()
{
	prisonsRemaining = std::max (0, prisonsRemaining - 1);
}

const std::vector<ArtifactID> & CMapGenerator::getQuestArtsRemaning() const
{
	return questArtifacts;
}

void CMapGenerator::banQuestArt(const ArtifactID & id)
{
	map->map().allowedArtifact[id] = false;
	vstd::erase_if_present(questArtifacts, id);
}

Zone * CMapGenerator::getZoneWater() const
{
	for(auto & z : map->getZones())
		if(z.second->getType() == ETemplateZoneType::WATER)
			return z.second.get();
	return nullptr;
}

VCMI_LIB_NAMESPACE_END