/*
 * Southampton University Map App
 * Copyright (C) 2011  Christopher Baines
 * 
 * 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 2
 * 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 net.cbaines.suma;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.SQLException;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;

import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
import com.j256.ormlite.dao.Dao;
import com.j256.ormlite.support.ConnectionSource;
import com.j256.ormlite.table.TableUtils;

public class DatabaseHelper extends OrmLiteSqliteOpenHelper {

	private static final String DATABASE_PATH = "/data/data/net.cbaines.suma/databases/";
	private static final String DATABASE_NAME = "data.db";

	private static final int DATABASE_VERSION = 41;

	private static final String TAG = "DatabaseHelper";

	// the DAO object we use to access the SimpleData table
	private Dao<Building, String> buildingDao = null;
	private Dao<BusStop, String> busStopDao = null;
	private Dao<BusRoute, Integer> busRouteDao = null;
	private Dao<RouteStop, Integer> routeStopsDao = null;
	private Dao<Site, String> siteDao = null;
	private Dao<Bus, Integer> busDao = null;

	private Context context;

	public DatabaseHelper(Context context) {
		super(context, DATABASE_NAME, null, DATABASE_VERSION);
		Log.i(TAG, "Database Helper created");
		this.context = context;
	}

	@Override
	public void onCreate(SQLiteDatabase database, ConnectionSource connectionSource) {
		try {
			Log.i(DatabaseHelper.class.getName(), "onCreate");
			TableUtils.createTable(connectionSource, Building.class);
			TableUtils.createTable(connectionSource, BusStop.class);
			TableUtils.createTable(connectionSource, BusRoute.class);
			TableUtils.createTable(connectionSource, RouteStop.class);
			TableUtils.createTable(connectionSource, Site.class);
			TableUtils.createTable(connectionSource, Bus.class);
		} catch (SQLException e) {
			Log.e(DatabaseHelper.class.getName(), "Can't create database", e);
			throw new RuntimeException(e);
		}
	}

	@Override
	public void onUpgrade(SQLiteDatabase database, ConnectionSource connectionSource, int oldVersion, int newVersion) {
		try {
			Log.i(DatabaseHelper.class.getName(), "onUpgrade");
			copyDataBase();

		} catch (IOException e) {
			e.printStackTrace();
		}

	}

	/**
	 * Returns the Database Access Object (DAO) for our SimpleData class. It
	 * will create it or just give the cached value.
	 */
	public Dao<Building, String> getBuildingDao() throws SQLException {
		if (buildingDao == null) {
			buildingDao = getDao(Building.class);
		}
		return buildingDao;
	}

	/**
	 * Returns the Database Access Object (DAO) for our SimpleData class. It
	 * will create it or just give the cached value.
	 */
	public Dao<BusStop, String> getBusStopDao() throws SQLException {
		if (busStopDao == null) {
			busStopDao = getDao(BusStop.class);
		}
		return busStopDao;
	}

	/**
	 * Returns the Database Access Object (DAO) for our SimpleData class. It
	 * will create it or just give the cached value.
	 */
	public Dao<BusRoute, Integer> getBusRouteDao() throws SQLException {
		if (busRouteDao == null) {
			busRouteDao = getDao(BusRoute.class);
		}
		return busRouteDao;
	}

	/**
	 * Returns the Database Access Object (DAO) for our SimpleData class. It
	 * will create it or just give the cached value.
	 */
	public Dao<RouteStop, Integer> getRouteStopsDao() throws SQLException {
		if (routeStopsDao == null) {
			routeStopsDao = getDao(RouteStop.class);
		}
		return routeStopsDao;
	}

	/**
	 * Returns the Database Access Object (DAO) for our SimpleData class. It
	 * will create it or just give the cached value.
	 */
	public Dao<Site, String> getSiteDao() throws SQLException {
		if (siteDao == null) {
			siteDao = getDao(Site.class);
		}
		return siteDao;
	}

	/**
	 * Returns the Database Access Object (DAO) for our SimpleData class. It
	 * will create it or just give the cached value.
	 */
	public Dao<Bus, Integer> getBusDao() throws SQLException {
		if (busDao == null) {
			busDao = getDao(Bus.class);
		}
		return busDao;
	}

	/**
	 * Check if the database already exist to avoid re-copying the file each
	 * time you open the application.
	 * 
	 * @return true if it exists, false if it doesn't
	 */
	public boolean checkDataBase() {
		Log.i(TAG, "Check database");

		/*
		 * SQLiteDatabase checkDB = null;
		 * 
		 * try { String myPath = DATABASE_PATH + DATABASE_NAME; checkDB =
		 * SQLiteDatabase.openDatabase(myPath, null,
		 * SQLiteDatabase.OPEN_READONLY); } catch (SQLiteException e) {
		 * 
		 * // database does't exist yet.
		 * 
		 * }
		 * 
		 * if (checkDB != null) {
		 * 
		 * checkDB.close();
		 * 
		 * }
		 * 
		 * Log.i(TAG, "Finished checking database"); return checkDB != null ?
		 * true : false;
		 */

		File dbFile = new File(DATABASE_PATH + DATABASE_NAME);
		return dbFile.exists();
	}

	/**
	 * Copies your database from your local assets-folder to the just created
	 * empty database in the system folder, from where it can be accessed and
	 * handled. This is done by transfering bytestream.
	 * */
	public void copyDataBase() throws IOException {
		Log.i(TAG, "Begining copy database");

		InputStream myInput = context.getAssets().open(DATABASE_NAME);

		// Path to the just created empty db
		String outFileName = DATABASE_PATH + DATABASE_NAME;

		File database = new File(outFileName);
		if (database.exists()) {
			database.delete();
		}

		// Open the empty db as the output stream
		OutputStream myOutput = new FileOutputStream(outFileName);

		// transfer bytes from the inputfile to the outputfile
		byte[] buffer = new byte[1024];
		int length;
		while ((length = myInput.read(buffer)) > 0) {
			myOutput.write(buffer, 0, length);
		}

		// Close the streams
		myOutput.flush();
		myOutput.close();
		myInput.close();

		// getWritableDatabase().close();

		Log.i(TAG, "Finished copying db");

	}

	/**
	 * Creates a empty database on the system and rewrites it with your own
	 * database.
	 * */
	public void createDataBase() throws IOException {

		boolean dbExist = checkDataBase();

		if (dbExist) {
			// do nothing - database already exist
		} else {

			try {
				Log.i(TAG, "Copy database");
				copyDataBase();
			} catch (IOException e) {
				throw new Error("Error copying database");
			}
		}

	}

	/**
	 * Close the database connections and clear any cached DAOs.
	 */
	@Override
	public void close() {
		super.close();
		buildingDao = null;
		busStopDao = null;
		busRouteDao = null;
		routeStopsDao = null;
		siteDao = null;
		busDao = null;
	}
}