/**
 * cemu_UI
 * 
 * Copyright 2017-2019  <@Seil0>
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 */

package com.cemu_UI.controller;

import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import javax.imageio.ImageIO;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.apache.commons.io.FileUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;

import com.cemu_UI.datatypes.UIROMDataType;

import javafx.collections.FXCollections;
import javafx.collections.ObservableList;

public class DBController {

	private static DBController instance = null;
	private ArrayList<String> entries = new ArrayList<>();
	private String DB_PATH_LocalGames;
	private String DB_PATH_ReverenceGames;
	private Connection connectionLocal = null;
	private Connection connectionReverence = null;
	private static final Logger LOGGER = LogManager.getLogger(DBController.class.getName());
	
	public DBController() {
		
	}
	
	public static DBController getInstance() {
		if (instance == null) {
			instance = new DBController();
		}
		
		return instance;
	}
	
	/**
	 * initialize the {@link DBController} with the database connection check if
	 * there is a need to create a new database refresh the database
	 */
	public void init() {
		initDatabaseConnection();
		createRomDatabase();
	}
	
	/**
	 * create a new connection to the HomeFlix.db database
	 * AutoCommit is set to false to prevent some issues, so manual commit is active!
	 * 
	 * TODO this should be called LocalGames
	 */
	private void initDatabaseConnection() {
		DB_PATH_LocalGames = XMLController.getDirCemuUI() + "/localRoms.db";
		DB_PATH_ReverenceGames = XMLController.getRference_gamesFile().getAbsolutePath();
		
		try {
			// create a database connection
			connectionLocal = DriverManager.getConnection("jdbc:sqlite:" + DB_PATH_LocalGames);
			connectionLocal.setAutoCommit(false);
			
			connectionReverence = DriverManager.getConnection("jdbc:sqlite:" + DB_PATH_ReverenceGames);
			connectionReverence.setAutoCommit(false);
		} catch (SQLException e) {
			// if the error message is "out of memory", it probably means no database file is found
			LOGGER.error("error while loading the Local- or ReverenceGames database", e);
		}
		
		LOGGER.info("Local- and ReverenceGames database loaded successfull");
	}
	
	/**
	 * creating the local_roms table in localRoms.db
	 * if the table has no entries, call loadRomDirectory
	 * 
	 * TODO the local_roms table should be called LocalGames
	 */
	void createRomDatabase() {
		try {
			Statement stmt = connectionLocal.createStatement();
			stmt.executeUpdate("create table if not exists local_roms (title, coverPath, romPath, titleID, productCode, region, lastPlayed, timePlayed)");
			connectionLocal.commit();
			stmt.close();
		} catch (SQLException e) {
			LOGGER.error("error while creating local-games database", e);
		}
	}
	
	/**
	 * refresh database to contain all (new added) games
	 */
	public void refreshDataBase() {
		LOGGER.info("<========== starting refreshing database ==========>");
		
		entries.clear();
		
		try {
			Statement stmt = connectionLocal.createStatement();
			ResultSet rs = stmt.executeQuery("SELECT * FROM local_roms");
			while (rs.next()) {
				entries.add(rs.getString(2));
			}
			stmt.close();
			rs.close();
		} catch (SQLException e) {
			LOGGER.error("error while loading ROMs from ROM database, local_roms table", e);
		}
		
		if (entries.size() == 0) {
			loadAllGames();
		}
		
		LOGGER.info("<========== finished refreshing database ==========>");
	}

	// add a game to the database
	public void addGame(String title, String coverPath, String romPath, String titleID, String productCode, String region, String lastPlayed, String timePlayed) throws SQLException{
		Statement stmt = connectionLocal.createStatement();
		stmt.executeUpdate("insert into local_roms values ('"+title+"','"+coverPath+"','"+romPath+"','"+titleID+"',"
				+ "'"+productCode+"','"+region+"','"+lastPlayed+"','"+timePlayed+"')");
		connectionLocal.commit();
		stmt.close();
		LOGGER.info("added \""+title+"\" to ROM database");
	}
	
	// remove a game from the database
	public void removeGame(String titleID) throws SQLException{
		Statement stmt = connectionLocal.createStatement();
		stmt.executeUpdate("delete from local_roms where titleID = '"+titleID+"'");
		connectionLocal.commit();
		stmt.close();
		LOGGER.info("removed \""+titleID+"\" from ROM database");
	}
	
	/**
	 * load all games from the database to a ObservableList, order entries by title
	 * @return a ObservableList that contains all local games from the database
	 */
	public ObservableList<UIROMDataType> loadAllGames() {
		ObservableList<UIROMDataType> games = FXCollections.observableArrayList();
		LOGGER.info("loading all local games from the database ...");
		try {
			Statement stmt = connectionLocal.createStatement(); 
			ResultSet rs = stmt.executeQuery("SELECT * FROM local_roms"); 
			while (rs.next()) {
				games.add(new UIROMDataType(rs.getString("romPath"), rs.getString("titleID"), rs.getString("title"),
						rs.getString("coverPath")));
			}
			stmt.close();
			rs.close();
		} catch (Exception e) {
			LOGGER.error("error while loading all local games from the database", e);
		}
		
		return games;
	}
	
	/**
	 * load one game from the database
	 * @param titleID	the titleID of the game you wish to get
	 * @return			the game you asked for
	 */
	public UIROMDataType loadSingleGame(String titleID) {
		UIROMDataType game = null;
		LOGGER.info("loading a single game (ID: {}) from the database ...", titleID);
		try { 
			PreparedStatement ps = connectionLocal.prepareStatement("SELECT * FROM local_roms where titleID = ?");
			ps.setString(1, titleID);
			ResultSet rs = ps.executeQuery();
			
			while (rs.next()) {
				game = new UIROMDataType(rs.getString("romPath"), rs.getString("titleID"), rs.getString("title"),
						rs.getString("coverPath"));
			}
			rs.close();
			ps.close();
		}catch (Exception e){
			LOGGER.error("error while loading a single game into the mainWindowController", e);
		}
		
		return game;
	}
	
	/**
	 * get all .rpx files from a given directory and add them to the games database if they don't exist there
	 * @param directory where to search for the .rpx files
	 */
	public void loadRomDirectory(String directory){
		File dir = new File(directory);
		File appFile;
		String[] extensions = new String[] { "rpx", "jsp" };
		File pictureCache = XMLController.getPictureCache();
		String coverPath;	
		try {
			Statement stmt = connectionReverence.createStatement();
			List<File> files = (List<File>) FileUtils.listFiles(dir, extensions, true);
			LOGGER.info("<============================== start loading ROM Directory ==============================>");
			LOGGER.info("Getting all .rpx files in " + dir.getCanonicalPath()+" including those in subdirectories");
			// for all files in dir get the app.xml
			for (File file : files) {
				appFile = new File(file.getParent() + "/app.xml");
				DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
				DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
				Document document = documentBuilder.parse(appFile);
				String title_ID = document.getElementsByTagName("title_id").item(0).getTextContent(); // get titile_ID from app.xml
				title_ID = title_ID.substring(0, 8) + "-" + title_ID.substring(8, title_ID.length());
				LOGGER.info("Name: " + file.getName() + "; Title ID: " + title_ID);
				ResultSet rs = stmt.executeQuery("SELECT * FROM games WHERE TitleID = '" + title_ID + "';");
				
				// for all elements in the games table check if it's already present, else add it
				while (rs.next()) {
					if (checkAddEntry(rs.getString(2))) {
						LOGGER.info(rs.getString(2) + ": game already in database");
					} else {
						LOGGER.info("adding cover to cache ...");
						BufferedImage originalImage = ImageIO.read(new URL(rs.getString(6)));// change path to where file is located
						int type = originalImage.getType() == 0 ? BufferedImage.TYPE_INT_ARGB : originalImage.getType();
						BufferedImage resizeImagePNG = resizeImage(originalImage, type, 400, 600);

						ImageIO.write(resizeImagePNG, "png", new File(pictureCache + "/" + rs.getString(3) + ".png"));
						coverPath = pictureCache + "/" + rs.getString(3) + ".png";
						LOGGER.info(rs.getString(2) + ": adding ROM");
						addGame(rs.getString(2), coverPath, file.getCanonicalPath(), rs.getString(1), rs.getString(3),
								rs.getString(5), "", "0");
					}
				}
			}
			LOGGER.info("<============================= finished loading ROM Directory ============================>");
		} catch (IOException | SQLException | ParserConfigurationException | SAXException e) {
			LOGGER.error("error while loading ROMs from directory", e);
		}
	}
	
	/**
	 * check if there is a game with the given name already in the database
	 * @param title game title
	 * @return true if the game exists, false if not
	 * @throws SQLException
	 */
	private boolean checkAddEntry(String title) throws SQLException{
		Statement stmt = connectionLocal.createStatement();
		boolean check = false;
		ResultSet rs = stmt.executeQuery("SELECT * FROM local_roms WHERE title = '"+title+"';");
		while (rs.next()) {
			check = true;
		}
		return check;
	}
	
	@SuppressWarnings("unused")
	private void checkRemoveEntry() {
		/**
		 *  TODO needs to be implemented!
		 *  don't show ROM on the UI, but keep all parameter in case it's showing up again ask if old data should be used
		 */
		//LOGGER.info("check if entry removed not done yet!");
	}
	
	/**
	 * getting info for a game with titleID
	 * @param titleID Title-ID of the Game
	 * @return title, coverPath, romPath, titleID (in this order)
	 */
	public String[] getGameInfo(String titleID){
		String[] gameInfo = new String[4];
		LOGGER.info("getting game info for titleID: "+titleID+" ..."); 
		try { 
			Statement stmt = connectionLocal.createStatement(); 
			ResultSet rs = stmt.executeQuery("SELECT * FROM local_roms where titleID = '"+titleID+"'"); 
			while (rs.next()) {
				gameInfo[0] = rs.getString(1);// title
				gameInfo[1] = rs.getString(2);// coverPath
				gameInfo[2] = rs.getString(3);// romPath
				gameInfo[3] = rs.getString(4);// titleID
			}
			stmt.close();
			rs.close();
		}catch (Exception e){
			LOGGER.error("error while getting game info", e);
		}
		return gameInfo;
	}

	public void setGameInfo(String title, String coverPath, String romPath, String titleID){
		LOGGER.info("setting game info for titleID: "+titleID+" ..."); 
		try { 
			Statement stmt = connectionLocal.createStatement(); 
			stmt.executeUpdate("UPDATE local_roms SET title = '" + title + "', coverPath = '" + coverPath + "',"
					+ " romPath = '" + romPath + "' WHERE titleID = '"+titleID+"';");
			connectionLocal.commit();
			stmt.close();	
		}catch (Exception e){
			LOGGER.error("error while setting game info", e);
		}
	}
	
	public void setLastPlayed(String titleID){
		try{
			Statement stmt = connectionLocal.createStatement(); 
			stmt.executeUpdate("UPDATE local_roms SET lastPlayed=date('now') WHERE titleID = '"+titleID+"';");
			connectionLocal.commit();
			stmt.close();
		}catch(SQLException e){
			LOGGER.error("failed to set the last played", e);
		}
	}
	
	public String getLastPlayed(String titleID){
		String lastPlayed = null;
		try{
			Statement stmt = connectionLocal.createStatement(); 
			ResultSet rs = stmt.executeQuery("SELECT lastPlayed FROM local_roms WHERE titleID = '"+titleID+"';" );
			lastPlayed = rs.getString(1);
			stmt.close();
			rs.close();
		}catch(SQLException e){
			LOGGER.error("failed to get the last played", e);
		}
		return lastPlayed;
	}
	
	public void setTotalPlaytime(String timePlayed, String titleID){
		try{
			Statement stmt = connectionLocal.createStatement(); 
			stmt.executeUpdate("UPDATE local_roms SET timePlayed='"+timePlayed+"' WHERE titleID = '"+titleID+"';");
			connectionLocal.commit();
			stmt.close();
		}catch(SQLException e){
			LOGGER.error("failed to set total play time", e);
			e.printStackTrace();
		}
	}
	
	public String getTotalPlaytime(String titleID){
		String timePlayed = null;
		try{
			Statement stmt = connectionLocal.createStatement(); 
			ResultSet rs = stmt.executeQuery("SELECT timePlayed FROM local_roms WHERE titleID = '"+titleID+"';" );
			timePlayed = rs.getString(1);
			stmt.close();
			rs.close();
		}catch(SQLException e){
			LOGGER.error("failed to get total play time", e);
		}
		return timePlayed;
	}
	
	private static BufferedImage resizeImage(BufferedImage originalImage, int type, int IMG_WIDTH, int IMG_HEIGHT) {
	    BufferedImage resizedImage = new BufferedImage(IMG_WIDTH, IMG_HEIGHT, type);
	    Graphics2D g = resizedImage.createGraphics();
	    g.drawImage(originalImage, 0, 0, IMG_WIDTH, IMG_HEIGHT, null);
	    g.dispose();

	    return resizedImage;
	}
	
}