/*
 * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */
package org.opendaylight.controller.sal.restconf.impl.websockets.client;

import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame;
import io.netty.handler.codec.http.websocketx.PongWebSocketFrame;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketClientHandshaker;
import io.netty.handler.codec.http.websocketx.WebSocketFrame;
import io.netty.util.CharsetUtil;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class WebSocketClientHandler extends SimpleChannelInboundHandler<Object> {

    private static final Logger logger = LoggerFactory.getLogger(WebSocketClientHandler.class.toString());
    private final WebSocketClientHandshaker handshaker;
    private ChannelPromise handshakeFuture;
    private IClientMessageCallback messageListener;


    public WebSocketClientHandler(WebSocketClientHandshaker handshaker,IClientMessageCallback listener) {
        this.handshaker = handshaker;
        this.messageListener = listener;
    }

    public ChannelFuture handshakeFuture() {
        return handshakeFuture;
    }

    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
        handshakeFuture = ctx.newPromise();
    }

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        handshaker.handshake(ctx.channel());
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        logger.info("WebSocket Client disconnected!");
    }

    @Override
    public void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
        Channel ch = ctx.channel();
        if (!handshaker.isHandshakeComplete()) {
            handshaker.finishHandshake(ch, (FullHttpResponse) msg);
            logger.info("WebSocket Client connected!");
            handshakeFuture.setSuccess();
            return;
        }

        if (msg instanceof FullHttpResponse) {
            FullHttpResponse response = (FullHttpResponse) msg;
            throw new Exception("Unexpected FullHttpResponse (getStatus=" + response.getStatus() + ", content="
                    + response.content().toString(CharsetUtil.UTF_8) + ')');
        }

        messageListener.onMessageReceived(msg);
        WebSocketFrame frame = (WebSocketFrame) msg;

        if (frame instanceof PongWebSocketFrame) {
            logger.info("WebSocket Client received pong");
        } else if (frame instanceof CloseWebSocketFrame) {
            logger.info("WebSocket Client received closing");
            ch.close();
        }
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        cause.printStackTrace();

        if (!handshakeFuture.isDone()) {
            handshakeFuture.setFailure(cause);
        }

        ctx.close();
    }
}