/*

 * Copyright (c) 2017, 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.

 */

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.nio.ByteBuffer;

import java.nio.MappedByteBuffer;

import java.util.Arrays;

import java.util.concurrent.Flow;

import java.util.concurrent.Flow.Publisher;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.concurrent.atomic.AtomicInteger;

import java.util.concurrent.atomic.AtomicLong;

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 java.net.http.HttpClient;

import java.net.http.HttpRequest;

import java.net.http.HttpResponse;

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 static java.util.stream.Collectors.joining;

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

import static java.net.http.HttpRequest.BodyPublishers.fromPublisher;

import static java.net.http.HttpResponse.BodyHandlers.ofString;

import static org.testng.Assert.assertEquals;

import static org.testng.Assert.assertThrows;

import static org.testng.Assert.assertTrue;

import static org.testng.Assert.fail;

/*

 * @test

 * @summary Basic tests for Flow adapter Publishers

 * @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

 *          java.logging

 *          jdk.httpserver

 * @library /lib/testlibrary http2/server

 * @build Http2TestServer

 * @build jdk.testlibrary.SimpleSSLContext

 * @run testng/othervm FlowAdapterPublisherTest

 */

public class FlowAdapterPublisherTest {

    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;

    String httpsURI;

    String http2URI;

    String https2URI;

    @DataProvider(name = "uris")

    public Object[][] variants() {

        return new Object[][]{

                { httpURI   },

                { httpsURI  },

                { http2URI  },

                { https2URI },

        };

    }

    static final Class<NullPointerException> NPE = NullPointerException.class;

    static final Class<IllegalArgumentException> IAE = IllegalArgumentException.class;

    @Test

    public void testAPIExceptions() {

        assertThrows(NPE, () -> fromPublisher(null));

        assertThrows(NPE, () -> fromPublisher(null, 1));

        assertThrows(IAE, () -> fromPublisher(new BBPublisher(), 0));

        assertThrows(IAE, () -> fromPublisher(new BBPublisher(), -1));

        assertThrows(IAE, () -> fromPublisher(new BBPublisher(), Long.MIN_VALUE));

        Publisher publisher = fromPublisher(new BBPublisher());

        assertThrows(NPE, () -> publisher.subscribe(null));

    }

    //  Flow.Publisher<ByteBuffer>

    @Test(dataProvider = "uris")

    void testByteBufferPublisherUnknownLength(String url) {

        String[] body = new String[] { "You know ", "it's summer ", "in Ireland ",

                "when the ", "rain gets ", "warmer." };

        HttpClient client = HttpClient.newBuilder().sslContext(sslContext).build();

        HttpRequest request = HttpRequest.newBuilder(URI.create(url))

                .POST(fromPublisher(new BBPublisher(body))).build();

        HttpResponse<String> response = client.sendAsync(request, ofString(UTF_8)).join();

        String text = response.body();

        System.out.println(text);

        assertEquals(response.statusCode(), 200);

        assertEquals(text, Arrays.stream(body).collect(joining()));

    }

    @Test(dataProvider = "uris")

    void testByteBufferPublisherFixedLength(String url) {

        String[] body = new String[] { "You know ", "it's summer ", "in Ireland ",

                "when the ", "rain gets ", "warmer." };

        int cl = Arrays.stream(body).mapToInt(String::length).sum();

        HttpClient client = HttpClient.newBuilder().sslContext(sslContext).build();

        HttpRequest request = HttpRequest.newBuilder(URI.create(url))

                .POST(fromPublisher(new BBPublisher(body), cl)).build();

        HttpResponse<String> response = client.sendAsync(request, ofString(UTF_8)).join();

        String text = response.body();

        System.out.println(text);

        assertEquals(response.statusCode(), 200);

        assertEquals(text, Arrays.stream(body).collect(joining()));

    }

    // Flow.Publisher<MappedByteBuffer>

    @Test(dataProvider = "uris")

    void testMappedByteBufferPublisherUnknownLength(String url) {

        String[] body = new String[] { "God invented ", "whiskey to ", "keep the ",

                "Irish from ", "ruling the ", "world." };

        HttpClient client = HttpClient.newBuilder().sslContext(sslContext).build();

        HttpRequest request = HttpRequest.newBuilder(URI.create(url))

                .POST(fromPublisher(new MBBPublisher(body))).build();

        HttpResponse<String> response = client.sendAsync(request, ofString(UTF_8)).join();

        String text = response.body();

        System.out.println(text);

        assertEquals(response.statusCode(), 200);

        assertEquals(text, Arrays.stream(body).collect(joining()));

    }

    @Test(dataProvider = "uris")

    void testMappedByteBufferPublisherFixedLength(String url) {

        String[] body = new String[] { "God invented ", "whiskey to ", "keep the ",

                "Irish from ", "ruling the ", "world." };

        int cl = Arrays.stream(body).mapToInt(String::length).sum();

        HttpClient client = HttpClient.newBuilder().sslContext(sslContext).build();

        HttpRequest request = HttpRequest.newBuilder(URI.create(url))

                .POST(fromPublisher(new MBBPublisher(body), cl)).build();

        HttpResponse<String> response = client.sendAsync(request, ofString(UTF_8)).join();

        String text = response.body();

        System.out.println(text);

        assertEquals(response.statusCode(), 200);

        assertEquals(text, Arrays.stream(body).collect(joining()));

    }

    // The following two tests depend on Exception detail messages, which is

    // not ideal, but necessary to discern correct behavior. They should be

    // updated if the exception message is updated.

    @Test(dataProvider = "uris")

    void testPublishTooFew(String url) throws InterruptedException {

        String[] body = new String[] { "You know ", "it's summer ", "in Ireland ",

                "when the ", "rain gets ", "warmer." };

        int cl = Arrays.stream(body).mapToInt(String::length).sum() + 1; // length + 1

        HttpClient client = HttpClient.newBuilder().sslContext(sslContext).build();

        HttpRequest request = HttpRequest.newBuilder(URI.create(url))

                .POST(fromPublisher(new BBPublisher(body), cl)).build();

        try {

            HttpResponse<String> response = client.send(request, ofString(UTF_8));

            fail("Unexpected response: " + response);

        } catch (IOException expected) {

            assertMessage(expected, "Too few bytes returned");

        }

    }

    @Test(dataProvider = "uris")

    void testPublishTooMany(String url) throws InterruptedException {

        String[] body = new String[] { "You know ", "it's summer ", "in Ireland ",

                "when the ", "rain gets ", "warmer." };

        int cl = Arrays.stream(body).mapToInt(String::length).sum() - 1; // length - 1

        HttpClient client = HttpClient.newBuilder().sslContext(sslContext).build();

        HttpRequest request = HttpRequest.newBuilder(URI.create(url))

                .POST(fromPublisher(new BBPublisher(body), cl)).build();

        try {

            HttpResponse<String> response = client.send(request, ofString(UTF_8));

            fail("Unexpected response: " + response);

        } catch (IOException expected) {

            assertMessage(expected, "Too many bytes in request body");

        }

    }

    private void assertMessage(Throwable t, String contains) {

        if (!t.getMessage().contains(contains)) {

            String error = "Exception message:[" + t.toString() + "] doesn't contain [" + contains + "]";

            throw new AssertionError(error, t);

        }

    }

    static class BBPublisher extends AbstractPublisher

        implements Flow.Publisher<ByteBuffer>

    {

        BBPublisher(String... bodyParts) { super(bodyParts); }

        @Override

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

            this.subscriber = subscriber;

            subscriber.onSubscribe(new InternalSubscription());

        }

    }

    static class MBBPublisher extends AbstractPublisher

        implements Flow.Publisher<MappedByteBuffer>

    {

        MBBPublisher(String... bodyParts) { super(bodyParts); }

        @Override

        public void subscribe(Flow.Subscriber<? super MappedByteBuffer> subscriber) {

            this.subscriber = subscriber;

            subscriber.onSubscribe(new InternalSubscription());

        }

    }

    static abstract class AbstractPublisher {

        private final String[] bodyParts;

        protected volatile Flow.Subscriber subscriber;

        AbstractPublisher(String... bodyParts) {

            this.bodyParts = bodyParts;

        }

        class InternalSubscription implements Flow.Subscription {

            private final AtomicLong demand = new AtomicLong();

            private final AtomicBoolean cancelled = new AtomicBoolean();

            private volatile int position;

            private static final int IDLE    =  1;

            private static final int PUSHING =  2;

            private static final int AGAIN   =  4;

            private final AtomicInteger state = new AtomicInteger(IDLE);

            @Override

            public void request(long n) {

                if (n <= 0L) {

                    subscriber.onError(new IllegalArgumentException(

                            "non-positive subscription request"));

                    return;

                }

                if (cancelled.get()) {

                    return;

                }

                while (true) {

                    long prev = demand.get(), d;

                    if ((d = prev + n) < prev) // saturate

                        d = Long.MAX_VALUE;

                    if (demand.compareAndSet(prev, d))

                        break;

                }

                while (true) {

                    int s = state.get();

                    if (s == IDLE) {

                        if (state.compareAndSet(IDLE, PUSHING)) {

                            while (true) {

                                push();

                                if (state.compareAndSet(PUSHING, IDLE))

                                    return;

                                else if (state.compareAndSet(AGAIN, PUSHING))

                                    continue;

                            }

                        }

                    } else if (s == PUSHING) {

                        if (state.compareAndSet(PUSHING, AGAIN))

                            return;

                    } else if (s == AGAIN){

                        // do nothing, the pusher will already rerun

                        return;

                    } else {

                        throw new AssertionError("Unknown state:" + s);

                    }

                }

            }

            private void push() {

                long prev;

                while ((prev = demand.get()) > 0) {

                    if (!demand.compareAndSet(prev, prev -1))

                        continue;

                    int index = position;

                    if (index < bodyParts.length) {

                        position++;

                        subscriber.onNext(ByteBuffer.wrap(bodyParts[index].getBytes(UTF_8)));

                    }

                }

                if (position == bodyParts.length && !cancelled.get()) {

                    cancelled.set(true);

                    subscriber.onComplete();

                }

            }

            @Override

            public void cancel() {

                if (cancelled.compareAndExchange(false, true))

                    return;  // already cancelled

            }

        }

    }

    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");

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

        httpTestServer = HttpServer.create(sa, 0);

        httpTestServer.createContext("/http1/echo", new Http1EchoHandler());

        httpURI = "http://" + serverAuthority(httpTestServer) + "/http1/echo";

        httpsTestServer = HttpsServer.create(sa, 0);

        httpsTestServer.setHttpsConfigurator(new HttpsConfigurator(sslContext));

        httpsTestServer.createContext("/https1/echo", new Http1EchoHandler());

        httpsURI = "https://" + serverAuthority(httpsTestServer) + "/https1/echo";

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

        http2TestServer.addHandler(new Http2EchoHandler(), "/http2/echo");

        http2URI = "http://" + http2TestServer.serverAuthority() + "/http2/echo";

        https2TestServer.addHandler(new Http2EchoHandler(), "/https2/echo");

        https2URI = "https://" + https2TestServer.serverAuthority() + "/https2/echo";

        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 class Http1EchoHandler implements HttpHandler {

        @Override

        public void handle(HttpExchange t) throws IOException {

            try (InputStream is = t.getRequestBody();

                 OutputStream os = t.getResponseBody()) {

                byte[] bytes = is.readAllBytes();

                t.sendResponseHeaders(200, bytes.length);

                os.write(bytes);

            }

        }

    }

    static class Http2EchoHandler implements Http2Handler {

        @Override

        public void handle(Http2TestExchange t) throws IOException {

            try (InputStream is = t.getRequestBody();

                 OutputStream os = t.getResponseBody()) {

                byte[] bytes = is.readAllBytes();

                t.sendResponseHeaders(200, bytes.length);

                os.write(bytes);

            }

        }

    }

}