/*
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */
package org.apache.hc.core5.http2.examples;

import java.security.Provider;
import java.security.Security;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Future;

import javax.net.ssl.SSLContext;

import org.apache.hc.core5.concurrent.FutureCallback;
import org.apache.hc.core5.http.Header;
import org.apache.hc.core5.http.HttpConnection;
import org.apache.hc.core5.http.HttpHost;
import org.apache.hc.core5.http.HttpResponse;
import org.apache.hc.core5.http.Message;
import org.apache.hc.core5.http.impl.bootstrap.HttpAsyncRequester;
import org.apache.hc.core5.http.nio.AsyncClientEndpoint;
import org.apache.hc.core5.http.nio.support.AsyncClientPipeline;
import org.apache.hc.core5.http.protocol.HttpCoreContext;
import org.apache.hc.core5.http2.HttpVersionPolicy;
import org.apache.hc.core5.http2.config.H2Config;
import org.apache.hc.core5.http2.frame.RawFrame;
import org.apache.hc.core5.http2.impl.nio.H2StreamListener;
import org.apache.hc.core5.http2.impl.nio.bootstrap.H2RequesterBootstrap;
import org.apache.hc.core5.http2.ssl.ConscryptClientTlsStrategy;
import org.apache.hc.core5.io.CloseMode;
import org.apache.hc.core5.ssl.SSLContexts;
import org.apache.hc.core5.util.Timeout;
import org.conscrypt.Conscrypt;

/**
 * This example demonstrates how to execute HTTP/2 requests over TLS connections
 * with Conscrypt TLS library.
 */
public class H2ConscriptRequestExecutionExample {

    public static void main(final String[] args) throws Exception {

        // Create and start requester
        final H2Config h2Config = H2Config.custom()
                .setPushEnabled(false)
                .build();

        final Provider conscryptProvider = Conscrypt.newProviderBuilder()
                .provideTrustManager(true)
                .build();

        Security.insertProviderAt(conscryptProvider, 1);

        final SSLContext sslContext = SSLContexts.custom()
                .build();

        final HttpAsyncRequester requester = H2RequesterBootstrap.bootstrap()
                .setH2Config(h2Config)
                // For JRE versions 11 or newer the standard H2ClientTlsStrategy should be used instead
                .setTlsStrategy(new ConscryptClientTlsStrategy(sslContext))
                .setVersionPolicy(HttpVersionPolicy.NEGOTIATE)
                .setStreamListener(new H2StreamListener() {

                    @Override
                    public void onHeaderInput(final HttpConnection connection, final int streamId, final List<? extends Header> headers) {
                        for (int i = 0; i < headers.size(); i++) {
                            System.out.println(connection.getRemoteAddress() + " (" + streamId + ") << " + headers.get(i));
                        }
                    }

                    @Override
                    public void onHeaderOutput(final HttpConnection connection, final int streamId, final List<? extends Header> headers) {
                        for (int i = 0; i < headers.size(); i++) {
                            System.out.println(connection.getRemoteAddress() + " (" + streamId + ") >> " + headers.get(i));
                        }
                    }

                    @Override
                    public void onFrameInput(final HttpConnection connection, final int streamId, final RawFrame frame) {
                    }

                    @Override
                    public void onFrameOutput(final HttpConnection connection, final int streamId, final RawFrame frame) {
                    }

                    @Override
                    public void onInputFlowControl(final HttpConnection connection, final int streamId, final int delta, final int actualSize) {
                    }

                    @Override
                    public void onOutputFlowControl(final HttpConnection connection, final int streamId, final int delta, final int actualSize) {
                    }

                })
                .create();
        Runtime.getRuntime().addShutdownHook(new Thread(() -> {
            System.out.println("HTTP requester shutting down");
            requester.close(CloseMode.GRACEFUL);
        }));
        requester.start();

        final HttpHost target = new HttpHost("https", "nghttp2.org", 443);
        final Future<AsyncClientEndpoint> future = requester.connect(target, Timeout.ofDays(5));
        final AsyncClientEndpoint clientEndpoint = future.get();

        final String[] requestUris = new String[]{"/httpbin/ip", "/httpbin/user-agent", "/httpbin/headers"};

        final CountDownLatch latch = new CountDownLatch(requestUris.length);
        for (final String requestUri : requestUris) {
            clientEndpoint.execute(
                    AsyncClientPipeline.assemble()
                            .request()
                            .get(target, requestUri)
                            .response()
                            .asString()
                            .result(new FutureCallback<Message<HttpResponse, String>>() {

                                @Override
                                public void completed(final Message<HttpResponse, String> message) {
                                    clientEndpoint.releaseAndReuse();
                                    final HttpResponse response = message.head();
                                    final String body = message.body();
                                    System.out.println(requestUri + "->" + response.getCode() + " " + response.getVersion());
                                    System.out.println(body);
                                    latch.countDown();
                                }

                                @Override
                                public void failed(final Exception ex) {
                                    clientEndpoint.releaseAndDiscard();
                                    System.out.println(requestUri + "->" + ex);
                                    latch.countDown();
                                }

                                @Override
                                public void cancelled() {
                                    clientEndpoint.releaseAndDiscard();
                                    System.out.println(requestUri + " cancelled");
                                    latch.countDown();
                                }

                            })
                            .create(),
                    null,
                    HttpCoreContext.create());
        }

        latch.await();
        System.out.println("Shutting down I/O reactor");
        requester.initiateShutdown();
    }

}
