#include <fstream>
#include "game.h"

class ConfigBuilder{
public:
	ConfigData collectedData;
	void parseFile(const string& fname);
	void readConfig();
	void dumpInternalValues();
private:
	map<string, string> internalValues;
	string& getString(const configKey& key);
	char getChar(const configKey& key);
	int getInt(const configKey& key);
	nsGraphics::RGBAcolor getColor(const configKey& key);
	void getList(const configKey& key, vector<string>&);
};

void ConfigBuilder::dumpInternalValues(){
	for(const auto& ite : internalValues){
		cerr << ite.first << " -> " << ite.second << endl;
	}
}

void trimSpaces(string& str){
	str.erase(0, str.find_first_not_of(' '));
}

/*
 * WARNING : This implementation of YAML is not meant to detect and report errors in a non YAML-compliant file
 */

void ConfigBuilder::parseFile(const string& fname) {
	ifstream file(fname);
	if(!file.is_open())throw runtime_error("Error while opening config.yml. Check file location ?");

	vector<string> keyParts;
	unsigned listIndex;
	while (!file.eof()) {
		string line;
		getline(file, line);
		auto match = line.find('#');
		if (match != string::npos)line.erase(match);
		if (line.empty())continue;

		unsigned currentIndent = 0;
		while (line[currentIndent] == ' ')++currentIndent;

		if(line[currentIndent]=='-'){
			string value = line.substr(currentIndent+1);
			trimSpaces(value);

			string fullKey;
			for (unsigned i = 0; i < currentIndent; ++i) {
				fullKey.append(keyParts[i]);
				fullKey.append(".");
			}
			// lists are just treated as sections with key 0,1,2...
			fullKey.append(to_string((listIndex)));
			++listIndex;
			internalValues[fullKey] = value;

		}else{
			match = line.find(':');
			if (match == string::npos)throw runtime_error("Invalid line : " + line);
			string key = line.substr(0, match);
			string value = line.substr(match + 1);
			trimSpaces(key);
			trimSpaces(value);
			if (value.empty()) {
				keyParts.resize(currentIndent);
				keyParts.push_back(key);
				listIndex = 0;
			} else {
				string fullKey;
				for (unsigned i = 0; i < currentIndent; ++i) {
					fullKey.append(keyParts[i]);
					fullKey.append(".");
				}
				fullKey.append(key);
				internalValues[fullKey] = value;
			}
		}
	}

	file.close();
}

void ConfigBuilder::readConfig() {

	vector<string> tmp;
	getList("grid", tmp);

	// we are essentially going to translate a line-oriented config to a column-oriented grid

	unsigned maxSize = 0;
	for(string& s : tmp){
		if(s.size()>maxSize)maxSize = s.size();
	}
	collectedData.grid.resize(maxSize);

	for(string& s : tmp){
		unsigned i=0;
		for(;i<s.size();++i){
			switch(toupper(s[i])){
				case 'A':{
					collectedData.grid[i].push_back(Invader::TYPEA);
					break;
				}
				case 'B':{
					collectedData.grid[i].push_back(Invader::TYPEB);
					break;
				}
				case 'C':{
					collectedData.grid[i].push_back(Invader::TYPEC);
					break;
				}
				case ' ':{
					collectedData.grid[i].push_back(Invader::NONE);
					break;
				}
				default:{
					throw runtime_error("Invalid invader ID in grid definition : "+ to_string(s[i]));
				}
			}
		}
		while(i<maxSize){
			collectedData.grid[i].push_back(Invader::NONE);
			++i;
		}
	}

	// players
	collectedData.playersWidth = getInt("players.width");
	collectedData.startXPosition = getInt("players.startXPosition");
	collectedData.playersSpeed = getInt("players.speed");
	collectedData.playersFireCooldown = getInt("players.fireCooldown");

	// the scalability behind the vector of players is only an illusion, because we force player count to be 1 or 2
	// It was done so the 2+ players implementation could be easier in the future, if wanted
	collectedData.playerDefs.resize(2);
	collectedData.playerDefs[0].color = getColor("players.user1.color");
	collectedData.playerDefs[0].keys.left = getChar("players.user1.keys.left");
	collectedData.playerDefs[0].keys.right = getChar("players.user1.keys.right");
	collectedData.playerDefs[0].keys.shoot = getChar("players.user1.keys.shoot");

	collectedData.playerDefs[1].color = getColor("players.user2.color");
	collectedData.playerDefs[1].keys.left = getChar("players.user2.keys.left");
	collectedData.playerDefs[1].keys.right = getChar("players.user2.keys.right");
	collectedData.playerDefs[1].keys.shoot = getChar("players.user2.keys.shoot");

	// invaders
	collectedData.invadersSize = getInt("invaders.size");
	collectedData.invadersSpeed = getInt("invaders.speed");
	collectedData.invadersDistance = getInt("invaders.distance");
	collectedData.invadersFireCooldown = getInt("invaders.fireCooldown");

	// projectiles
	collectedData.missilesWidth = getInt("projectiles.missiles.width");
	collectedData.missilesLength = collectedData.missilesWidth*PROJ_LENGTH_FACTOR;
	collectedData.missilesSpeed = getInt("projectiles.missiles.speed");
	collectedData.missilesColor = getColor("projectiles.missiles.color");

	collectedData.torpedosWidth = getInt("projectiles.torpedos.width");
	collectedData.torpedosLength = collectedData.torpedosWidth*PROJ_LENGTH_FACTOR;
	collectedData.torpedosSpeed = getInt("projectiles.missiles.speed");
	collectedData.torpedosColor = getColor("projectiles.torpedos.color");
}

int ConfigBuilder::getInt(const configKey& key) {
	return stoi(getString(key));
}

char ConfigBuilder::getChar(const configKey& key) {
	return getString(key)[0];
}

string& ConfigBuilder::getString(const configKey& key) {
	if(internalValues.contains(key)){
		return internalValues.at(key);
	}else{
		throw runtime_error("Non-existent key requested : "+key);
	}
}

void ConfigBuilder::getList(const configKey& key, vector<string>& toPopulate) {
	size_t i=0;
	string fullKey = key+".0";
	if(!internalValues.contains(fullKey))throw runtime_error("Non-existent list key requested : "+key);

	do{
		toPopulate.push_back(internalValues.at(fullKey));
		++i;
		fullKey = key+"."+to_string(i);
	}while(internalValues.contains(key+"."+to_string(i)));
}

nsGraphics::RGBAcolor ConfigBuilder::getColor(const configKey& key) {
	// switch do not work with strings, and I don't want to implement a constexpr hash function
	string colorStr = getString(key);
	if (colorStr == "black")return nsGraphics::KBlack;
	else if (colorStr == "white")return nsGraphics::KWhite;
	else if (colorStr == "red")return nsGraphics::KRed;
	else if (colorStr == "lime")return nsGraphics::KLime;
	else if (colorStr == "blue")return nsGraphics::KBlue;
	else if (colorStr == "yellow")return nsGraphics::KYellow;
	else if (colorStr == "cyan")return nsGraphics::KCyan;
	else if (colorStr == "magenta")return nsGraphics::KMagenta;
	else if (colorStr == "silver")return nsGraphics::KSilver;
	else if (colorStr == "gray")return nsGraphics::KGray;
	else if (colorStr == "maroon")return nsGraphics::KMaroon;
	else if (colorStr == "olive")return nsGraphics::KOlive;
	else if (colorStr == "green")return nsGraphics::KGreen;
	else if (colorStr == "purple")return nsGraphics::KPurple;
	else if (colorStr == "teal")return nsGraphics::KTeal;
	else if (colorStr == "navy")return nsGraphics::KNavy;
	else throw runtime_error("Invalid color string : "+colorStr);
}


/**
 *
 * @return false if there was an error
 */
bool Game::reloadConfig() {
	map<string, string> strValues;
	ConfigBuilder builder;
	bool parsed = false;
	try{
		builder.parseFile("config.yml");
		parsed = true;
		builder.readConfig();
	}catch(runtime_error& e){
		if(parsed)cerr << "An error occured while reading the configuration :" << endl;
		else cerr << "An error occured while parsing the configuration :" << endl;
		cerr << e.what() << endl;
		if(parsed){
			cerr << "Parsed keys :" << endl;
			builder.dumpInternalValues();
		}
		cerr << "(The old configuration was kept in memory)" << endl;
		return false;
	}
	confData = builder.collectedData;
	return true;
}