/*
 *  Copyright (c) 2019, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 *
 *  WSO2 Inc. licenses this file to you 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.wso2.micro.gateway.tests.common.HTTP2Server;

import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.ssl.ApplicationProtocolNames;
import io.netty.handler.ssl.ApplicationProtocolNegotiationHandler;

/**
 * Negotiates with the browser if HTTP2 or HTTP is going to be used. Once decided, the Netty
 * pipeline is setup with the correct handlers for the selected protocol.
 */
public class Http2OrHttpHandler extends ApplicationProtocolNegotiationHandler {

    private static final int MAX_CONTENT_LENGTH = 1024 * 100;

    protected Http2OrHttpHandler() {
        super(ApplicationProtocolNames.HTTP_1_1);
    }

    @Override
    protected void configurePipeline(ChannelHandlerContext ctx, String protocol) throws Exception {
        if (ApplicationProtocolNames.HTTP_2.equals(protocol)) {
            ctx.pipeline().addLast(new Http2HandlerBuilder().build());
            return;
        }

        if (ApplicationProtocolNames.HTTP_1_1.equals(protocol)) {
            ctx.pipeline().addLast(new HttpServerCodec(),
                    new HttpObjectAggregator(MAX_CONTENT_LENGTH),
                    new Http1Handler("ALPN Negotiation"));
            return;
        }

        throw new IllegalStateException("unknown protocol: " + protocol);
    }
}
