package com.tesora.dve.db.mysql.portal;

/*
 * #%L
 * Tesora Inc.
 * Database Virtualization Engine
 * %%
 * Copyright (C) 2011 - 2014 Tesora Inc.
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License, version 3,
 * as published by the Free Software Foundation.
 * 
 * This program 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 Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 * #L%
 */

import com.tesora.dve.server.global.HostService;
import com.tesora.dve.singleton.Singletons;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.AttributeKey;

import com.tesora.dve.db.mysql.libmy.MyHandshakeErrorResponse;
import com.tesora.dve.server.connectionmanager.SSConnection;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.concurrent.Callable;

@Sharable
public class ConnectionHandlerAdapter extends ChannelInboundHandlerAdapter {
	private static final Logger logger = LoggerFactory.getLogger(ConnectionHandlerAdapter.class);

	static public AttributeKey<SSConnection> SSCON_KEY = new AttributeKey<SSConnection>("SSConnection");

	@Override
	public void channelActive(final ChannelHandlerContext ctx) throws Exception {
		super.channelActive(ctx);
		
		try {
			SSConnection ssConnection = new SSConnection();
			ssConnection.injectChannel(ctx.channel());
			ctx.channel().attr(SSCON_KEY).set(ssConnection);
			
			ssConnection.addShutdownHook(new Thread(){
				@Override
				public void run() {
					ctx.channel().close();
				}
			});
		} catch (Exception e) {
			ctx.channel().writeAndFlush(new MyHandshakeErrorResponse(e));
		}
	}			

	@Override
	public void channelInactive(ChannelHandlerContext ctx) throws Exception {
		final SSConnection ssConnection = ctx.channel().attr(SSCON_KEY).getAndRemove();

		if(ssConnection != null){
            Singletons.require(HostService.class).submit( new Callable<Object>() {
                @Override
                public Object call() throws Exception {
                    try{
                        ssConnection.close();
                    } catch (Exception e){
                        logger.warn("Problem closing ssconnection {}",ssConnection,e);
                    }
                    return null;
                }
            });

        }
		
		super.channelInactive(ctx);
	}
	
	private static final class InstanceHolder {
		private static final ConnectionHandlerAdapter INSTANCE = new ConnectionHandlerAdapter();
	}
	
	public static ConnectionHandlerAdapter getInstance() {
		return InstanceHolder.INSTANCE;
	}
}