/*
 * Copyright 2019 Anton Tananaev (anton@traccar.org)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.traccar.handler;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelDuplexHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.channel.socket.DatagramChannel;
import io.netty.channel.socket.DatagramPacket;
import org.traccar.NetworkMessage;

import java.net.InetSocketAddress;

public class NetworkMessageHandler extends ChannelDuplexHandler {

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) {
        if (ctx.channel() instanceof DatagramChannel) {
            DatagramPacket packet = (DatagramPacket) msg;
            ctx.fireChannelRead(new NetworkMessage(packet.content(), packet.sender()));
        } else if (msg instanceof ByteBuf) {
            ByteBuf buffer = (ByteBuf) msg;
            ctx.fireChannelRead(new NetworkMessage(buffer, ctx.channel().remoteAddress()));
        }
    }

    @Override
    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
        if (msg instanceof NetworkMessage) {
            NetworkMessage message = (NetworkMessage) msg;
            if (ctx.channel() instanceof DatagramChannel) {
                InetSocketAddress recipient = (InetSocketAddress) message.getRemoteAddress();
                InetSocketAddress sender = (InetSocketAddress) ctx.channel().localAddress();
                ctx.write(new DatagramPacket((ByteBuf) message.getMessage(), recipient, sender), promise);
            } else {
                ctx.write(message.getMessage(), promise);
            }
        } else {
            ctx.write(msg, promise);
        }
    }

}