/*
 * 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.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Collection;
import java.util.LinkedList;
import javax.annotation.Nonnull;

import com.google.common.base.Preconditions;

import net.minecraft.nbt.CompressedStreamTools;
import net.minecraft.nbt.NBTTagCompound;

import appeng.core.AELog;


/**
 * @author thatsIch
 * @version rv3 - 30.05.2015
 * @since rv3 30.05.2015
 */
final class SpawnData implements IWorldSpawnData, IOnWorldStartable, IOnWorldStoppable
{
	@Nonnull
	private final File spawnDirectory;
	@Nonnull
	private final MeteorDataNameEncoder encoder;

	public SpawnData( @Nonnull final File spawnDirectory )
	{
		Preconditions.checkNotNull( spawnDirectory );
		Preconditions.checkArgument( spawnDirectory.isDirectory() );

		this.spawnDirectory = spawnDirectory;
		this.encoder = new MeteorDataNameEncoder( 4 );
	}

	@Override
	public void onWorldStart()
	{

	}

	@Override
	public void setGenerated( int dim, int chunkX, int chunkZ ) {
		synchronized( SpawnData.class )
		{
			NBTTagCompound data = this.loadSpawnData( dim, chunkX, chunkZ );

			// edit.
			data.setBoolean( chunkX + "," + chunkZ, true );

			this.writeSpawnData( dim, chunkX, chunkZ, data );
		}
	}

	@Override
	public boolean hasGenerated( int dim, int chunkX, int chunkZ )
	{
		synchronized( SpawnData.class )
		{
			NBTTagCompound data = this.loadSpawnData( dim, chunkX, chunkZ );
			return data.getBoolean( chunkX + "," + chunkZ );
		}
	}

	@Override
	public boolean addNearByMeteorites( int dim, int chunkX, int chunkZ, NBTTagCompound newData )
	{
		synchronized( SpawnData.class )
		{
			NBTTagCompound data = this.loadSpawnData( dim, chunkX, chunkZ );

			// edit.
			int size = data.getInteger( "num" );
			data.setTag( String.valueOf( size ), newData );
			data.setInteger( "num", size + 1 );

			this.writeSpawnData( dim, chunkX, chunkZ, data );

			return true;
		}
	}

	@Override
	public Collection<NBTTagCompound> getNearByMeteorites( int dim, int chunkX, int chunkZ )
	{
		Collection<NBTTagCompound> ll = new LinkedList<NBTTagCompound>();

		synchronized( SpawnData.class )
		{
			for( int x = -1; x <= 1; x++ )
			{
				for( int z = -1; z <= 1; z++ )
				{
					int cx = x + ( chunkX >> 4 );
					int cz = z + ( chunkZ >> 4 );

					NBTTagCompound data = this.loadSpawnData( dim, cx << 4, cz << 4 );

					if( data != null )
					{
						// edit.
						int size = data.getInteger( "num" );
						for( int s = 0; s < size; s++ )
						{
							ll.add( data.getCompoundTag( String.valueOf( s ) ) );
						}
					}
				}
			}
		}

		return ll;
	}

	@Override
	public void onWorldStop()
	{

	}

	private NBTTagCompound loadSpawnData( int dim, int chunkX, int chunkZ )
	{
		if( !Thread.holdsLock( SpawnData.class ) )
		{
			throw new IllegalStateException( "Invalid Request" );
		}

		NBTTagCompound data = null;
		final String fileName = this.encoder.encode( dim, chunkX, chunkZ );
		final File file = new File( this.spawnDirectory, fileName );

		if( file.isFile() )
		{
			FileInputStream fileInputStream = null;

			try
			{
				fileInputStream = new FileInputStream( file );
				data = CompressedStreamTools.readCompressed( fileInputStream );
			}
			catch( Throwable e )
			{
				data = new NBTTagCompound();
				AELog.error( e );
			}
			finally
			{
				if( fileInputStream != null )
				{
					try
					{
						fileInputStream.close();
					}
					catch( IOException e )
					{
						AELog.error( e );
					}
				}
			}
		}
		else
		{
			data = new NBTTagCompound();
		}

		return data;
	}

	private void writeSpawnData( int dim, int chunkX, int chunkZ, NBTTagCompound data )
	{
		if( !Thread.holdsLock( SpawnData.class ) )
		{
			throw new IllegalStateException( "Invalid Request" );
		}

		final String fileName = this.encoder.encode( dim, chunkX, chunkZ );
		final File file = new File( this.spawnDirectory, fileName );
		FileOutputStream fileOutputStream = null;

		try
		{
			fileOutputStream = new FileOutputStream( file );
			CompressedStreamTools.writeCompressed( data, fileOutputStream );
		}
		catch( Throwable e )
		{
			AELog.error( e );
		}
		finally
		{
			if( fileOutputStream != null )
			{
				try
				{
					fileOutputStream.close();
				}
				catch( IOException e )
				{
					AELog.error( e );
				}
			}
		}
	}
}