package com.emulation.net.codec;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.handler.codec.frame.FrameDecoder;

import com.emulation.model.player.Player;
import com.emulation.net.packet.Packet;
import com.emulation.net.packet.PacketExecute;
import com.emulation.net.packet.PacketType;
import com.emulation.util.Execution;
import com.emulation.world.World;

/**
 * Decodes a packet that will be
 * sent to the client, encoded
 * from there and then used accordingly.
 * @author Owner
 * @version 1.0
 */
public class Decoder extends FrameDecoder {

	/**
	 * Decode an Object which will be
	 * of type Packet and sent to the
	 * client.
	 */
	@Override
	protected Object decode(ChannelHandlerContext chc, Channel channel, ChannelBuffer cb) {
		Player player = World.getWorld().getChannelLocal().get(channel);
		// ISAACCipher isaac = (ISAACCipher) player.getAttribute("decryptor");
		int opcode = -1;
		int length = -1;
		if (cb.readableBytes() >= 1) {
			opcode = cb.readByte() & 0xFF;
			// opcode = (opcode - isaac.getNextKey()) & 0xFF;
			World.getWorld().getLogger().info("Writing and decoding opcode " + opcode + "...");
			length = Packet.getPacketSizes()[opcode];
		} else {
			return null;
		}
		if (length == -1) {
			if (cb.readableBytes() >= 1) {
				length = cb.readByte() & 0xFF;
			} else {
				return null;
			}
		}
		if (cb.readableBytes() >= length) {
			byte[] data = new byte[length];
			cb.readBytes(data);
			ChannelBuffer channelBuffer = ChannelBuffers.dynamicBuffer(data.length);
			channelBuffer.writeBytes(data);
			Packet packet = new Packet(opcode, PacketType.FIXED, channelBuffer);
			if ((player != null) && (packet != null)) {
				Execution.getScheduledExecutorService().submit(new PacketExecute(player, packet));
			}
			opcode = -1;
			length = -1;
			return packet;
		}
		return null;
	}
}