/*

 * 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

 * @bug 8201186

 * @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.BodyHandlers;

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.CompletionException;

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 java.util.function.Supplier;

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 implements HttpServerAdapters {

    SSLContext sslContext;

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

    HttpTestServer httpsTestServer;   // HTTPS/1.1

    HttpTestServer http2TestServer;   // HTTP/2 ( h2c )

    HttpTestServer 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 = 3;

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

    static final Executor executor = Executors.newCachedThreadPool();

    interface BHS extends Supplier<BodyHandler<Publisher<List<ByteBuffer>>>> {

        static BHS of(BHS impl, String name) {

            return new BHSImpl(impl, name);

        }

    }

    static final class BHSImpl implements BHS {

        final BHS supplier;

        final String name;

        BHSImpl(BHS impl, String name) {

            this.supplier = impl;

            this.name = name;

        }

        @Override

        public String toString() {

            return name;

        }

        @Override

        public BodyHandler<Publisher<List<ByteBuffer>>> get() {

            return supplier.get();

        }

    }

    static final Supplier<BodyHandler<Publisher<List<ByteBuffer>>>> OF_PUBLISHER_API =

            BHS.of(BodyHandlers::ofPublisher, "BodyHandlers::ofPublisher");

    static final Supplier<BodyHandler<Publisher<List<ByteBuffer>>>> OF_PUBLISHER_TEST =

            BHS.of(PublishingBodyHandler::new, "PublishingBodyHandler::new");

    @DataProvider(name = "variants")

    public Object[][] variants() {

        return new Object[][]{

                { httpURI_fixed,    false, OF_PUBLISHER_API },

                { httpURI_chunk,    false, OF_PUBLISHER_API },

                { httpsURI_fixed,   false, OF_PUBLISHER_API },

                { httpsURI_chunk,   false, OF_PUBLISHER_API },

                { http2URI_fixed,   false, OF_PUBLISHER_API },

                { http2URI_chunk,   false, OF_PUBLISHER_API },

                { https2URI_fixed,  false, OF_PUBLISHER_API },

                { https2URI_chunk,  false, OF_PUBLISHER_API },

                { httpURI_fixed,    true, OF_PUBLISHER_API },

                { httpURI_chunk,    true, OF_PUBLISHER_API },

                { httpsURI_fixed,   true, OF_PUBLISHER_API },

                { httpsURI_chunk,   true, OF_PUBLISHER_API },

                { http2URI_fixed,   true, OF_PUBLISHER_API },

                { http2URI_chunk,   true, OF_PUBLISHER_API },

                { https2URI_fixed,  true, OF_PUBLISHER_API },

                { https2URI_chunk,  true, OF_PUBLISHER_API },

                { httpURI_fixed,    false, OF_PUBLISHER_TEST },

                { httpURI_chunk,    false, OF_PUBLISHER_TEST },

                { httpsURI_fixed,   false, OF_PUBLISHER_TEST },

                { httpsURI_chunk,   false, OF_PUBLISHER_TEST },

                { http2URI_fixed,   false, OF_PUBLISHER_TEST },

                { http2URI_chunk,   false, OF_PUBLISHER_TEST },

                { https2URI_fixed,  false, OF_PUBLISHER_TEST },

                { https2URI_chunk,  false, OF_PUBLISHER_TEST },

                { httpURI_fixed,    true, OF_PUBLISHER_TEST },

                { httpURI_chunk,    true, OF_PUBLISHER_TEST },

                { httpsURI_fixed,   true, OF_PUBLISHER_TEST },

                { httpsURI_chunk,   true, OF_PUBLISHER_TEST },

                { http2URI_fixed,   true, OF_PUBLISHER_TEST },

                { http2URI_chunk,   true, OF_PUBLISHER_TEST },

                { https2URI_fixed,  true, OF_PUBLISHER_TEST },

                { https2URI_chunk,  true, OF_PUBLISHER_TEST },

        };

    }

    final ReferenceTracker TRACKER = ReferenceTracker.INSTANCE;

    HttpClient newHttpClient() {

        return TRACKER.track(HttpClient.newBuilder()

                         .executor(executor)

                         .sslContext(sslContext)

                         .build());

    }

    @Test(dataProvider = "variants")

    public void testExceptions(String uri, boolean sameClient, BHS handlers) 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 = handlers.get();

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

            try {

                response.body().subscribe(null);

                throw new RuntimeException("Expected NPE not thrown");

            } catch (NullPointerException x) {

                System.out.println("Got expected NPE: " + x);

            }

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

            // Publisher<List<ByteBuffer>>

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

            response.body().subscribe(ofString);

            BodySubscriber<String> ofString2 = BodySubscribers.ofString(UTF_8);

            response.body().subscribe(ofString2);

            try {

                ofString2.getBody().toCompletableFuture().join();

                throw new RuntimeException("Expected ISE not thrown");

            } catch (CompletionException x) {

                Throwable cause = x.getCause();

                if (cause instanceof  IllegalStateException) {

                    System.out.println("Got expected ISE: " + cause);

                } else {

                    throw x;

                }

            }

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

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

            assertEquals(body, "");

        }

    }

    @Test(dataProvider = "variants")

    public void testNoBody(String uri, boolean sameClient, BHS handlers) 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 = handlers.get();

            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, BHS handlers) 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 = handlers.get();

            // 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, BHS handlers) 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 = handlers.get();

            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, BHS handlers) 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 = handlers.get();

            // 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(HttpResponse.ResponseInfo rinfo) {

            assertEquals(rinfo.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 IllegalStateException("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

        HttpTestHandler h1_fixedLengthHandler = new HTTP_FixedLengthHandler();

        HttpTestHandler h1_chunkHandler = new HTTP_VariableLengthHandler();

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

        httpTestServer = HttpTestServer.of(HttpServer.create(sa, 0));

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

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

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

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

        HttpsServer httpsServer = HttpsServer.create(sa, 0);

        httpsServer.setHttpsConfigurator(new HttpsConfigurator(sslContext));

        httpsTestServer = HttpTestServer.of(httpsServer);

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

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

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

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

        // HTTP/2

        HttpTestHandler h2_fixedLengthHandler = new HTTP_FixedLengthHandler();

        HttpTestHandler h2_chunkedHandler = new HTTP_VariableLengthHandler();

        http2TestServer = HttpTestServer.of(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 = HttpTestServer.of(new Http2TestServer("localhost", true, sslContext));

        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 {

        Thread.sleep(100);

        AssertionError fail = TRACKER.check(500);

        try {

            httpTestServer.stop();

            httpsTestServer.stop();

            http2TestServer.stop();

            https2TestServer.stop();

        } finally {

            if (fail != null) {

                throw fail;

            }

        }

    }

    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 HTTP_FixedLengthHandler implements HttpTestHandler {

        @Override

        public void handle(HttpTestExchange t) throws IOException {

            out.println("HTTP_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, 0);  //no body

            }

        }

    }

    static class HTTP_VariableLengthHandler implements HttpTestHandler {

        @Override

        public void handle(HttpTestExchange t) throws IOException {

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

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

                is.readAllBytes();

            }

            t.sendResponseHeaders(200, -1);  //chunked or variable

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

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

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

                    int chunkLen = bytes.length/10;

                    if (chunkLen == 0) {

                        os.write(bytes);

                    } else {

                        int count = 0;

                        for (int i=0; i<10; i++) {

                            os.write(bytes, count, chunkLen);

                            os.flush();

                            count += chunkLen;

                        }

                        os.write(bytes, count, bytes.length % chunkLen);

                        count += bytes.length % chunkLen;

                        assert count == bytes.length;

                    }

                }

            } else {

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

            }

        }

    }

}