/*

 * 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

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 * questions.

 */

/*

 * @test

 * @summary Checks correct handling of Publishers that call onComplete without demand

 * @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

 * @build Http2TestServer

 * @run testng/othervm CustomRequestPublisher

 */

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.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.util.Arrays;

import java.util.Optional;

import java.util.concurrent.CompletableFuture;

import java.util.concurrent.Flow;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.concurrent.atomic.AtomicInteger;

import java.util.concurrent.atomic.AtomicLong;

import java.util.function.Supplier;

import java.util.stream.Collectors;

import javax.net.ssl.SSLContext;

import javax.net.ssl.SSLSession;

import java.net.http.HttpClient;

import java.net.http.HttpRequest;

import java.net.http.HttpResponse;

import org.testng.annotations.AfterTest;

import org.testng.annotations.BeforeTest;

import org.testng.annotations.DataProvider;

import org.testng.annotations.Test;

import static java.lang.System.out;

import static java.net.http.HttpClient.Version.HTTP_1_1;

import static java.net.http.HttpClient.Version.HTTP_2;

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

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

import static org.testng.Assert.assertEquals;

import static org.testng.Assert.assertTrue;

import static org.testng.Assert.fail;

public class CustomRequestPublisher {

    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 = "variants")

    public Object[][] variants() {

        Supplier<BodyPublisher> fixedSupplier   = () -> new FixedLengthBodyPublisher();

        Supplier<BodyPublisher> unknownSupplier = () -> new UnknownLengthBodyPublisher();

        return new Object[][]{

                { httpURI,   fixedSupplier,   false },

                { httpURI,   unknownSupplier, false },

                { httpsURI,  fixedSupplier,   false },

                { httpsURI,  unknownSupplier, false },

                { http2URI,  fixedSupplier,   false },

                { http2URI,  unknownSupplier, false },

                { https2URI, fixedSupplier,   false,},

                { https2URI, unknownSupplier, false },

                { httpURI,   fixedSupplier,   true },

                { httpURI,   unknownSupplier, true },

                { httpsURI,  fixedSupplier,   true },

                { httpsURI,  unknownSupplier, true },

                { http2URI,  fixedSupplier,   true },

                { http2URI,  unknownSupplier, true },

                { https2URI, fixedSupplier,   true,},

                { https2URI, unknownSupplier, true },

        };

    }

    static final int ITERATION_COUNT = 10;

    /** Asserts HTTP Version, and SSLSession presence when applicable. */

    static void assertVersionAndSession(HttpResponse response, String uri) {

        if (uri.contains("http2") || uri.contains("https2"))

            assertEquals(response.version(), HTTP_2);

        else if (uri.contains("http1") || uri.contains("https1"))

            assertEquals(response.version(), HTTP_1_1);

        else

            fail("Unknown HTTP version in test for: " + uri);

        Optional<SSLSession> ssl = response.sslSession();

        if (uri.contains("https")) {

            assertTrue(ssl.isPresent(),

                    "Expected optional containing SSLSession but got:" + ssl);

            try {

                ssl.get().invalidate();

                fail("SSLSession is not immutable: " + ssl.get());

            } catch (UnsupportedOperationException expected) { }

        } else {

            assertTrue(!ssl.isPresent(), "UNEXPECTED non-empty optional:" + ssl);

        }

    }

    @Test(dataProvider = "variants")

    void test(String uri, Supplier<BodyPublisher> bpSupplier, boolean sameClient)

            throws Exception

    {

        HttpClient client = null;

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

            if (!sameClient || client == null)

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

            BodyPublisher bodyPublisher = bpSupplier.get();

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

                    .POST(bodyPublisher)

                    .build();

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

            out.println("Got response: " + resp);

            out.println("Got body: " + resp.body());

            assertTrue(resp.statusCode() == 200,

                    "Expected 200, got:" + resp.statusCode());

            assertEquals(resp.body(), bodyPublisher.bodyAsString());

            assertVersionAndSession(resp, uri);

        }

    }

    @Test(dataProvider = "variants")

    void testAsync(String uri, Supplier<BodyPublisher> bpSupplier, boolean sameClient)

            throws Exception

    {

        HttpClient client = null;

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

            if (!sameClient || client == null)

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

            BodyPublisher bodyPublisher = bpSupplier.get();

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

                    .POST(bodyPublisher)

                    .build();

            CompletableFuture<HttpResponse<String>> cf = client.sendAsync(request, ofString());

            HttpResponse<String> resp = cf.get();

            out.println("Got response: " + resp);

            out.println("Got body: " + resp.body());

            assertTrue(resp.statusCode() == 200,

                    "Expected 200, got:" + resp.statusCode());

            assertEquals(resp.body(), bodyPublisher.bodyAsString());

            assertVersionAndSession(resp, uri);

        }

    }

    /** A Publisher that returns an UNKNOWN content length. */

    static class UnknownLengthBodyPublisher extends BodyPublisher {

        @Override

        public long contentLength() {

            return -1;  // unknown

        }

    }

    /** A Publisher that returns a FIXED content length. */

    static class FixedLengthBodyPublisher extends BodyPublisher {

        final int LENGTH = Arrays.stream(BODY)

                .mapToInt(s-> s.getBytes(US_ASCII).length)

                .sum();

        @Override

        public long contentLength() {

            return LENGTH;

        }

    }

    /**

     * A Publisher that ( quite correctly ) invokes onComplete, after the last

     * item has been published, even without any outstanding demand.

     */

    static abstract class BodyPublisher implements HttpRequest.BodyPublisher {

        String[] BODY = new String[]

                { "Say ", "Hello ", "To ", "My ", "Little ", "Friend" };

        protected volatile Flow.Subscriber subscriber;

        @Override

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

            this.subscriber = subscriber;

            subscriber.onSubscribe(new InternalSubscription());

        }

        @Override

        public abstract long contentLength();

        String bodyAsString() {

            return Arrays.stream(BODY).collect(Collectors.joining());

        }

        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 < BODY.length) {

                        position++;

                        subscriber.onNext(ByteBuffer.wrap(BODY[index].getBytes(US_ASCII)));

                    }

                }

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

                    cancelled.set(true);

                    subscriber.onComplete();  // NOTE: onComplete without demand

                }

            }

            @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 = new Http2TestServer("localhost", true, sslContext);

        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);

            }

        }

    }

}