/*

 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @summary Tests an asynchronous BodySubscriber that completes

 *          immediately with a Publisher<List<ByteBuffer>>

 * @library /lib/testlibrary http2/server

 * @build jdk.testlibrary.SimpleSSLContext

 * @modules java.base/sun.net.www.http

 *          java.net.http/jdk.internal.net.http.common

 *          java.net.http/jdk.internal.net.http.frame

 *          java.net.http/jdk.internal.net.http.hpack

 * @run testng/othervm ResponsePublisher

 */

import com.sun.net.httpserver.HttpExchange;

import com.sun.net.httpserver.HttpHandler;

import com.sun.net.httpserver.HttpServer;

import com.sun.net.httpserver.HttpsConfigurator;

import com.sun.net.httpserver.HttpsServer;

import jdk.testlibrary.SimpleSSLContext;

import org.testng.annotations.AfterTest;

import org.testng.annotations.BeforeTest;

import org.testng.annotations.DataProvider;

import org.testng.annotations.Test;

import javax.net.ssl.SSLContext;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.net.InetAddress;

import java.net.InetSocketAddress;

import java.net.URI;

import java.net.http.HttpClient;

import java.net.http.HttpHeaders;

import java.net.http.HttpRequest;

import java.net.http.HttpResponse;

import java.net.http.HttpResponse.BodyHandler;

import java.net.http.HttpResponse.BodySubscriber;

import java.net.http.HttpResponse.BodySubscribers;

import java.nio.ByteBuffer;

import java.util.List;

import java.util.Objects;

import java.util.concurrent.CompletableFuture;

import java.util.concurrent.CompletionStage;

import java.util.concurrent.Executor;

import java.util.concurrent.Executors;

import java.util.concurrent.Flow;

import java.util.concurrent.Flow.Publisher;

import java.util.concurrent.atomic.AtomicReference;

import static java.lang.System.out;

import static java.nio.charset.StandardCharsets.UTF_8;

import static org.testng.Assert.assertEquals;

import static org.testng.Assert.assertNotNull;

import static org.testng.Assert.assertTrue;

public class ResponsePublisher {

    SSLContext sslContext;

    HttpServer httpTestServer;         // HTTP/1.1    [ 4 servers ]

    HttpsServer httpsTestServer;       // HTTPS/1.1

    Http2TestServer http2TestServer;   // HTTP/2 ( h2c )

    Http2TestServer https2TestServer;  // HTTP/2 ( h2  )

    String httpURI_fixed;

    String httpURI_chunk;

    String httpsURI_fixed;

    String httpsURI_chunk;

    String http2URI_fixed;

    String http2URI_chunk;

    String https2URI_fixed;

    String https2URI_chunk;

    static final int ITERATION_COUNT = 10;

    // a shared executor helps reduce the amount of threads created by the test

    static final Executor executor = Executors.newCachedThreadPool();

    @DataProvider(name = "variants")

    public Object[][] variants() {

        return new Object[][]{

                { httpURI_fixed,    false },

                { httpURI_chunk,    false },

                { httpsURI_fixed,   false },

                { httpsURI_chunk,   false },

                { http2URI_fixed,   false },

                { http2URI_chunk,   false },

                { https2URI_fixed,  false,},

                { https2URI_chunk,  false },

                { httpURI_fixed,    true },

                { httpURI_chunk,    true },

                { httpsURI_fixed,   true },

                { httpsURI_chunk,   true },

                { http2URI_fixed,   true },

                { http2URI_chunk,   true },

                { https2URI_fixed,  true,},

                { https2URI_chunk,  true },

        };

    }

    HttpClient newHttpClient() {

        return HttpClient.newBuilder()

                         .executor(executor)

                         .sslContext(sslContext)

                         .build();

    }

    @Test(dataProvider = "variants")

    public void testNoBody(String uri, boolean sameClient) throws Exception {

        HttpClient client = null;

        for (int i=0; i< ITERATION_COUNT; i++) {

            if (!sameClient || client == null)

                client = newHttpClient();

            HttpRequest req = HttpRequest.newBuilder(URI.create(uri))

                    .build();

            BodyHandler<Publisher<List<ByteBuffer>>> handler = new PublishingBodyHandler();

            HttpResponse<Publisher<List<ByteBuffer>>> response = client.send(req, handler);

            // We can reuse our BodySubscribers implementations to subscribe to the

            // Publisher<List<ByteBuffer>>

            BodySubscriber<String> ofString = BodySubscribers.ofString(UTF_8);

            // get the Publisher<List<ByteBuffer>> and

            // subscribe to it.

            response.body().subscribe(ofString);

            // Get the final result and compare it with the expected body

            String body = ofString.getBody().toCompletableFuture().get();

            assertEquals(body, "");

        }

    }

    @Test(dataProvider = "variants")

    public void testNoBodyAsync(String uri, boolean sameClient) throws Exception {

        HttpClient client = null;

        for (int i=0; i< ITERATION_COUNT; i++) {

            if (!sameClient || client == null)

                client = newHttpClient();

            HttpRequest req = HttpRequest.newBuilder(URI.create(uri))

                    .build();

            BodyHandler<Publisher<List<ByteBuffer>>> handler = new PublishingBodyHandler();

            // We can reuse our BodySubscribers implementations to subscribe to the

            // Publisher<List<ByteBuffer>>

            BodySubscriber<String> ofString = BodySubscribers.ofString(UTF_8);

            CompletableFuture<String> result =

                    client.sendAsync(req, handler).thenCompose(

                            (responsePublisher) -> {

                                // get the Publisher<List<ByteBuffer>> and

                                // subscribe to it.

                                responsePublisher.body().subscribe(ofString);

                                return ofString.getBody();

                            });

            // Get the final result and compare it with the expected body

            assertEquals(result.get(), "");

        }

    }

    @Test(dataProvider = "variants")

    public void testAsString(String uri, boolean sameClient) throws Exception {

        HttpClient client = null;

        for (int i=0; i< ITERATION_COUNT; i++) {

            if (!sameClient || client == null)

                client = newHttpClient();

            HttpRequest req = HttpRequest.newBuilder(URI.create(uri+"/withBody"))

                    .build();

            BodyHandler<Publisher<List<ByteBuffer>>> handler = new PublishingBodyHandler();

            HttpResponse<Publisher<List<ByteBuffer>>> response = client.send(req, handler);

            // We can reuse our BodySubscribers implementations to subscribe to the

            // Publisher<List<ByteBuffer>>

            BodySubscriber<String> ofString = BodySubscribers.ofString(UTF_8);

            // get the Publisher<List<ByteBuffer>> and

            // subscribe to it.

            response.body().subscribe(ofString);

            // Get the final result and compare it with the expected body

            String body = ofString.getBody().toCompletableFuture().get();

            assertEquals(body, WITH_BODY);

        }

    }

    @Test(dataProvider = "variants")

    public void testAsStringAsync(String uri, boolean sameClient) throws Exception {

        HttpClient client = null;

        for (int i=0; i< ITERATION_COUNT; i++) {

            if (!sameClient || client == null)

                client = newHttpClient();

            HttpRequest req = HttpRequest.newBuilder(URI.create(uri+"/withBody"))

                    .build();

            BodyHandler<Publisher<List<ByteBuffer>>> handler = new PublishingBodyHandler();

            // We can reuse our BodySubscribers implementations to subscribe to the

            // Publisher<List<ByteBuffer>>

            BodySubscriber<String> ofString = BodySubscribers.ofString(UTF_8);

            CompletableFuture<String> result = client.sendAsync(req, handler)

                    .thenCompose((responsePublisher) -> {

                        // get the Publisher<List<ByteBuffer>> and

                        // subscribe to it.

                        responsePublisher.body().subscribe(ofString);

                        return ofString.getBody();

                    });

            // Get the final result and compare it with the expected body

            String body = result.get();

            assertEquals(body, WITH_BODY);

        }

    }

    // A BodyHandler that returns PublishingBodySubscriber instances

    static class PublishingBodyHandler implements BodyHandler<Publisher<List<ByteBuffer>>> {

        @Override

        public BodySubscriber<Publisher<List<ByteBuffer>>> apply(int statusCode, HttpHeaders responseHeaders) {

            assertEquals(statusCode, 200);

            return new PublishingBodySubscriber();

        }

    }

    // A BodySubscriber that returns a Publisher<List<ByteBuffer>>

    static class PublishingBodySubscriber implements BodySubscriber<Publisher<List<ByteBuffer>>> {

        private final CompletableFuture<Flow.Subscription> subscriptionCF = new CompletableFuture<>();

        private final CompletableFuture<Flow.Subscriber<? super List<ByteBuffer>>> subscribedCF = new CompletableFuture<>();

        private AtomicReference<Flow.Subscriber<? super List<ByteBuffer>>> subscriberRef = new AtomicReference<>();

        private final CompletionStage<Publisher<List<ByteBuffer>>> body =

                //subscriptionCF.thenCompose((s) -> CompletableFuture.completedStage(this::subscribe));

                CompletableFuture.completedStage(this::subscribe);

        private void subscribe(Flow.Subscriber<? super List<ByteBuffer>> subscriber) {

            Objects.requireNonNull(subscriber, "subscriber must not be null");

            if (subscriberRef.compareAndSet(null, subscriber)) {

                subscriptionCF.thenAccept((s) -> {

                    subscriber.onSubscribe(s);

                    subscribedCF.complete(subscriber);

                });

            } else {

                subscriber.onSubscribe(new Flow.Subscription() {

                    @Override public void request(long n) { }

                    @Override public void cancel() { }

                });

                subscriber.onError(new IOException("This publisher has already one subscriber"));

            }

        }

        @Override

        public void onSubscribe(Flow.Subscription subscription) {

            subscriptionCF.complete(subscription);

        }

        @Override

        public void onNext(List<ByteBuffer> item) {

            assert subscriptionCF.isDone(); // cannot be called before onSubscribe()

            Flow.Subscriber<? super List<ByteBuffer>> subscriber = subscriberRef.get();

            assert subscriber != null; // cannot be called before subscriber calls request(1)

            subscriber.onNext(item);

        }

        @Override

        public void onError(Throwable throwable) {

            assert subscriptionCF.isDone(); // cannot be called before onSubscribe()

            // onError can be called before request(1), and therefore can

            // be called before subscriberRef is set.

            subscribedCF.thenAccept(s -> s.onError(throwable));

        }

        @Override

        public void onComplete() {

            assert subscriptionCF.isDone(); // cannot be called before onSubscribe()

            // onComplete can be called before request(1), and therefore can

            // be called before subscriberRef is set.

            subscribedCF.thenAccept(s -> s.onComplete());

        }

        @Override

        public CompletionStage<Publisher<List<ByteBuffer>>> getBody() {

            return body;

        }

    }

    static String serverAuthority(HttpServer server) {

        return InetAddress.getLoopbackAddress().getHostName() + ":"

                + server.getAddress().getPort();

    }

    @BeforeTest

    public void setup() throws Exception {

        sslContext = new SimpleSSLContext().get();

        if (sslContext == null)

            throw new AssertionError("Unexpected null sslContext");

        // HTTP/1.1

        HttpHandler h1_fixedLengthHandler = new HTTP1_FixedLengthHandler();

        HttpHandler h1_chunkHandler = new HTTP1_ChunkedHandler();

        InetSocketAddress sa = new InetSocketAddress(InetAddress.getLoopbackAddress(), 0);

        httpTestServer = HttpServer.create(sa, 0);

        httpTestServer.createContext("/http1/fixed", h1_fixedLengthHandler);

        httpTestServer.createContext("/http1/chunk", h1_chunkHandler);

        httpURI_fixed = "http://" + serverAuthority(httpTestServer) + "/http1/fixed";

        httpURI_chunk = "http://" + serverAuthority(httpTestServer) + "/http1/chunk";

        httpsTestServer = HttpsServer.create(sa, 0);

        httpsTestServer.setHttpsConfigurator(new HttpsConfigurator(sslContext));

        httpsTestServer.createContext("/https1/fixed", h1_fixedLengthHandler);

        httpsTestServer.createContext("/https1/chunk", h1_chunkHandler);

        httpsURI_fixed = "https://" + serverAuthority(httpsTestServer) + "/https1/fixed";

        httpsURI_chunk = "https://" + serverAuthority(httpsTestServer) + "/https1/chunk";

        // HTTP/2

        Http2Handler h2_fixedLengthHandler = new HTTP2_FixedLengthHandler();

        Http2Handler h2_chunkedHandler = new HTTP2_VariableHandler();

        http2TestServer = new Http2TestServer("localhost", false, 0);

        http2TestServer.addHandler(h2_fixedLengthHandler, "/http2/fixed");

        http2TestServer.addHandler(h2_chunkedHandler, "/http2/chunk");

        http2URI_fixed = "http://" + http2TestServer.serverAuthority() + "/http2/fixed";

        http2URI_chunk = "http://" + http2TestServer.serverAuthority() + "/http2/chunk";

        https2TestServer = new Http2TestServer("localhost", true, 0);

        https2TestServer.addHandler(h2_fixedLengthHandler, "/https2/fixed");

        https2TestServer.addHandler(h2_chunkedHandler, "/https2/chunk");

        https2URI_fixed = "https://" + https2TestServer.serverAuthority() + "/https2/fixed";

        https2URI_chunk = "https://" + https2TestServer.serverAuthority() + "/https2/chunk";

        httpTestServer.start();

        httpsTestServer.start();

        http2TestServer.start();

        https2TestServer.start();

    }

    @AfterTest

    public void teardown() throws Exception {

        httpTestServer.stop(0);

        httpsTestServer.stop(0);

        http2TestServer.stop();

        https2TestServer.stop();

    }

    static final String WITH_BODY = "Lorem ipsum dolor sit amet, consectetur" +

            " adipiscing elit, sed do eiusmod tempor incididunt ut labore et" +

            " dolore magna aliqua. Ut enim ad minim veniam, quis nostrud" +

            " exercitation ullamco laboris nisi ut aliquip ex ea" +

            " commodo consequat. Duis aute irure dolor in reprehenderit in " +

            "voluptate velit esse cillum dolore eu fugiat nulla pariatur." +

            " Excepteur sint occaecat cupidatat non proident, sunt in culpa qui" +

            " officia deserunt mollit anim id est laborum.";

    static class HTTP1_FixedLengthHandler implements HttpHandler {

        @Override

        public void handle(HttpExchange t) throws IOException {

            out.println("HTTP1_FixedLengthHandler received request to " + t.getRequestURI());

            try (InputStream is = t.getRequestBody()) {

                is.readAllBytes();

            }

            if (t.getRequestURI().getPath().endsWith("/withBody")) {

                byte[] bytes = WITH_BODY.getBytes(UTF_8);

                t.sendResponseHeaders(200, bytes.length);  // body

                try (OutputStream os = t.getResponseBody()) {

                    os.write(bytes);

                }

            } else {

                t.sendResponseHeaders(200, -1);  //no body

            }

        }

    }

    static class HTTP1_ChunkedHandler implements HttpHandler {

        @Override

        public void handle(HttpExchange t) throws IOException {

            out.println("HTTP1_ChunkedHandler received request to " + t.getRequestURI());

            try (InputStream is = t.getRequestBody()) {

                is.readAllBytes();

            }

            t.sendResponseHeaders(200, 0);  //chunked

            if (t.getRequestURI().getPath().endsWith("/withBody")) {

                byte[] bytes = WITH_BODY.getBytes(UTF_8);

                try (OutputStream os = t.getResponseBody()) {

                    os.write(bytes);

                }

            } else {

                t.getResponseBody().close();   // no body

            }

        }

    }

    static class HTTP2_FixedLengthHandler implements Http2Handler {

        @Override

        public void handle(Http2TestExchange t) throws IOException {

            out.println("HTTP2_FixedLengthHandler received request to " + t.getRequestURI());

            try (InputStream is = t.getRequestBody()) {

                is.readAllBytes();

            }

            if (t.getRequestURI().getPath().endsWith("/withBody")) {

                byte[] bytes = WITH_BODY.getBytes(UTF_8);

                t.sendResponseHeaders(200, bytes.length);  // body

                try (OutputStream os = t.getResponseBody()) {

                    os.write(bytes);

                }

            } else {

                t.sendResponseHeaders(200, -1);  //no body

            }

        }

    }

    static class HTTP2_VariableHandler implements Http2Handler {

        @Override

        public void handle(Http2TestExchange t) throws IOException {

            out.println("HTTP2_VariableHandler received request to " + t.getRequestURI());

            try (InputStream is = t.getRequestBody()) {

                is.readAllBytes();

            }

            t.sendResponseHeaders(200, 0);  //chunked

            if (t.getRequestURI().getPath().endsWith("/withBody")) {

                byte[] bytes = WITH_BODY.getBytes(UTF_8);

                try (OutputStream os = t.getResponseBody()) {

                    os.write(bytes);

                }

            } else {

                t.getResponseBody().close();   // no body

            }

        }

    }

}