/*
 * This file is part of Applied Energistics 2.
 * Copyright (c) 2013 - 2015, AlgorithmX2, All rights reserved.
 *
 * Applied Energistics 2 is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Applied Energistics 2 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Applied Energistics 2.  If not, see <http://www.gnu.org/licenses/lgpl>.
 */

package appeng.core.worlddata;


import java.io.File;
import java.util.List;
import java.util.concurrent.ThreadFactory;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;

import net.minecraft.server.MinecraftServer;
import net.minecraftforge.common.DimensionManager;
import net.minecraftforge.common.config.Configuration;

import appeng.core.AEConfig;
import appeng.services.CompassService;
import appeng.services.compass.CompassThreadFactory;


/**
 * Singleton access to anything related to world-based data.
 *
 * Data will change depending which world is loaded. Will probably not affect SMP at all since only one world is loaded,
 * but SSP more, cause they play on
 * different worlds.
 *
 * @author thatsIch
 * @version rv3 - 02.11.2015
 * @since rv3 30.05.2015
 */
public final class WorldData implements IWorldData
{
	private static final String AE2_DIRECTORY_NAME = "AE2";
	private static final String SETTING_FILE_NAME = "settings.cfg";
	private static final String SPAWNDATA_DIR_NAME = "spawndata";
	private static final String COMPASS_DIR_NAME = "compass";

	@Nullable
	private static IWorldData instance;

	private final IWorldPlayerData playerData;
	private final IWorldDimensionData dimensionData;
	private final IWorldGridStorageData storageData;
	private final IWorldCompassData compassData;
	private final IWorldSpawnData spawnData;

	private final List<IOnWorldStartable> startables;
	private final List<IOnWorldStoppable> stoppables;

	private final File ae2directory;
	private final File spawnDirectory;
	private final File compassDirectory;

	private final Configuration sharedConfig;

	private WorldData( @Nonnull final File worldDirectory )
	{
		Preconditions.checkNotNull( worldDirectory );
		Preconditions.checkArgument( worldDirectory.isDirectory() );

		this.ae2directory = new File( worldDirectory, AE2_DIRECTORY_NAME );
		this.spawnDirectory = new File( this.ae2directory, SPAWNDATA_DIR_NAME );
		this.compassDirectory = new File( this.ae2directory, COMPASS_DIR_NAME );

		final File settingsFile = new File( this.ae2directory, SETTING_FILE_NAME );
		this.sharedConfig = new Configuration( settingsFile, AEConfig.VERSION );

		final PlayerData playerData = new PlayerData( this.sharedConfig );
		final DimensionData dimensionData = new DimensionData( this.sharedConfig );
		final StorageData storageData = new StorageData( this.sharedConfig );

		final ThreadFactory compassThreadFactory = new CompassThreadFactory();
		final CompassService compassService = new CompassService( this.compassDirectory, compassThreadFactory );
		final CompassData compassData = new CompassData( this.compassDirectory, compassService );

		final IWorldSpawnData spawnData = new SpawnData( this.spawnDirectory );

		this.playerData = playerData;
		this.dimensionData = dimensionData;
		this.storageData = storageData;
		this.compassData = compassData;
		this.spawnData = spawnData;

		this.startables = Lists.<IOnWorldStartable>newArrayList( playerData, dimensionData, storageData );
		this.stoppables = Lists.<IOnWorldStoppable>newArrayList( playerData, dimensionData, storageData, compassData );
	}

	/**
	 * @return ae2 data related to a specific world
	 *
	 * @deprecated do not use singletons which are dependent on specific world state
	 */
	@Deprecated
	@Nonnull
	public static IWorldData instance()
	{
		return instance;
	}

	/**
	 * Requires to start up from external from here
	 *
	 * drawback of the singleton build style
	 * @param server  
	 */
	public static void onServerAboutToStart( MinecraftServer server )
	{
		File worldDirectory = DimensionManager.getCurrentSaveRootDirectory();
		if( worldDirectory == null )
		{
			worldDirectory = server.getActiveAnvilConverter().getSaveLoader( server.getFolderName(), false ).getWorldDirectory();
		}
		final WorldData newInstance = new WorldData( worldDirectory );

		instance = newInstance;
		newInstance.onServerStarting();
	}

	private void onServerStarting()
	{
		// check if ae2 folder already exists, else create
		if( !this.ae2directory.isDirectory() && !this.ae2directory.mkdir() )
		{
			throw new IllegalStateException( "Failed to create " + this.ae2directory.getAbsolutePath() );
		}

		// check if compass folder already exists, else create
		if( !this.compassDirectory.isDirectory() && !this.compassDirectory.mkdir() )
		{
			throw new IllegalStateException( "Failed to create " + this.compassDirectory.getAbsolutePath() );
		}

		// check if spawn data dir already exists, else create
		if( !this.spawnDirectory.isDirectory() && !this.spawnDirectory.mkdir() )
		{
			throw new IllegalStateException( "Failed to create " + this.spawnDirectory.getAbsolutePath() );
		}

		for( final IOnWorldStartable startable : this.startables )
		{
			startable.onWorldStart();
		}

		this.startables.clear();
	}

	@Override
	public void onServerStopping()
	{
		for( final IOnWorldStoppable stoppable : this.stoppables )
		{
			stoppable.onWorldStop();
		}
	}

	@Override
	public void onServerStoppped()
	{
		Preconditions.checkNotNull( instance );

		this.stoppables.clear();
		instance = null;
	}

	@Nonnull
	@Override
	public IWorldGridStorageData storageData()
	{
		return this.storageData;
	}

	@Nonnull
	@Override
	public IWorldPlayerData playerData()
	{
		return this.playerData;
	}

	@Nonnull
	@Override
	public IWorldDimensionData dimensionData()
	{
		return this.dimensionData;
	}

	@Nonnull
	@Override
	public IWorldCompassData compassData()
	{
		return this.compassData;
	}

	@Nonnull
	@Override
	public IWorldSpawnData spawnData()
	{
		return this.spawnData;
	}
}