/*

 * 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

 * @build DummyWebSocketServer

 * @run testng/othervm WebSocketTest

 */

import org.testng.annotations.Test;

import java.io.IOException;

import java.net.http.WebSocket;

import java.nio.ByteBuffer;

import java.nio.CharBuffer;

import java.nio.channels.SocketChannel;

import java.nio.charset.StandardCharsets;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.concurrent.CompletableFuture;

import java.util.concurrent.CompletionException;

import java.util.concurrent.CompletionStage;

import java.util.concurrent.TimeUnit;

import java.util.concurrent.TimeoutException;

import java.util.stream.Collectors;

import static java.net.http.HttpClient.newHttpClient;

import static java.net.http.WebSocket.NORMAL_CLOSURE;

import static org.testng.Assert.assertEquals;

import static org.testng.Assert.assertFalse;

import static org.testng.Assert.assertThrows;

import static org.testng.Assert.assertTrue;

import static org.testng.Assert.fail;

public class WebSocketTest {

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

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

    private static final Class<IllegalStateException> ISE = IllegalStateException.class;

    private static final Class<IOException> IOE = IOException.class;

    public void immediateAbort() throws Exception {

        try (DummyWebSocketServer server = serverWithCannedData(0x81, 0x00, 0x88, 0x00)) {

            server.open();

            CompletableFuture<Void> messageReceived = new CompletableFuture<>();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() {

                        @Override

                        public void onOpen(WebSocket webSocket) {

                            /* no initial request */

                        }

                        @Override

                        public CompletionStage<?> onText(WebSocket webSocket,

                                                         CharSequence message,

                                                         WebSocket.MessagePart part) {

                            messageReceived.complete(null);

                            return null;

                        }

                        @Override

                        public CompletionStage<?> onBinary(WebSocket webSocket,

                                                           ByteBuffer message,

                                                           WebSocket.MessagePart part) {

                            messageReceived.complete(null);

                            return null;

                        }

                        @Override

                        public CompletionStage<?> onPing(WebSocket webSocket,

                                                         ByteBuffer message) {

                            messageReceived.complete(null);

                            return null;

                        }

                        @Override

                        public CompletionStage<?> onPong(WebSocket webSocket,

                                                         ByteBuffer message) {

                            messageReceived.complete(null);

                            return null;

                        }

                        @Override

                        public CompletionStage<?> onClose(WebSocket webSocket,

                                                          int statusCode,

                                                          String reason) {

                            messageReceived.complete(null);

                            return null;

                        }

                    })

                    .join();

            ws.abort();

            // Each consecutive abort MUST be a no-op:

            ws.abort();

            assertTrue(ws.isInputClosed());

            assertTrue(ws.isOutputClosed());

            assertEquals(ws.getSubprotocol(), "");

            ws.abort();

            assertTrue(ws.isInputClosed());

            assertTrue(ws.isOutputClosed());

            assertEquals(ws.getSubprotocol(), "");

            // At this point request MUST be a no-op:

            ws.request(1);

            ws.request(Long.MAX_VALUE);

            // Throws IAE regardless of whether WebSocket is closed or not:

            assertThrows(IAE, () -> ws.request(Integer.MIN_VALUE));

            assertThrows(IAE, () -> ws.request(Long.MIN_VALUE));

            assertThrows(IAE, () -> ws.request(-1));

            assertThrows(IAE, () -> ws.request(0));

            // Even though there is a bunch of messages readily available on the

            // wire we shouldn't have received any of them as we aborted before

            // the first request

            try {

                messageReceived.get(10, TimeUnit.SECONDS);

                fail();

            } catch (TimeoutException expected) {

                System.out.println("Finished waiting");

            }

            assertCompletesExceptionally(IOE, ws.sendText("text!", false));

            assertCompletesExceptionally(IOE, ws.sendText("text!", true));

            assertCompletesExceptionally(IOE, ws.sendBinary(ByteBuffer.allocate(16), false));

            assertCompletesExceptionally(IOE, ws.sendBinary(ByteBuffer.allocate(16), true));

            assertCompletesExceptionally(IOE, ws.sendPing(ByteBuffer.allocate(16)));

            assertCompletesExceptionally(IOE, ws.sendPong(ByteBuffer.allocate(16)));

            // Checked last because it changes the state of WebSocket

            assertCompletesExceptionally(IOE, ws.sendClose(NORMAL_CLOSURE, "a reason"));

        }

    }

    private static DummyWebSocketServer serverWithCannedData(int... data) {

        byte[] copy = new byte[data.length];

        for (int i = 0; i < data.length; i++) {

            copy[i] = (byte) data[i];

        }

        return new DummyWebSocketServer() {

            @Override

            protected void serve(SocketChannel channel) throws IOException {

                ByteBuffer closeMessage = ByteBuffer.wrap(copy);

                channel.write(closeMessage);

                super.serve(channel);

            }

        };

    }

    private static void assertCompletesExceptionally(Class<? extends Throwable> clazz,

                                                     CompletableFuture<?> stage) {

        stage.handle((result, error) -> {

            if (error instanceof CompletionException) {

                Throwable cause = error.getCause();

                if (cause == null) {

                    throw new AssertionError("Unexpected null cause: " + error);

                }

                assertException(clazz, cause);

            } else {

                assertException(clazz, error);

            }

            return null;

        }).join();

    }

    private static void assertException(Class<? extends Throwable> clazz,

                                        Throwable t) {

        if (t == null) {

            throw new AssertionError("Expected " + clazz + ", caught nothing");

        }

        if (!clazz.isInstance(t)) {

            throw new AssertionError("Expected " + clazz + ", caught " + t);

        }

    }

    @Test

    public void sendMethodsThrowNPE() throws IOException {

        try (DummyWebSocketServer server = new DummyWebSocketServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            assertThrows(NPE, () -> ws.sendText(null, false));

            assertThrows(NPE, () -> ws.sendText(null, true));

            assertThrows(NPE, () -> ws.sendBinary(null, false));

            assertThrows(NPE, () -> ws.sendBinary(null, true));

            assertThrows(NPE, () -> ws.sendPing(null));

            assertThrows(NPE, () -> ws.sendPong(null));

            assertThrows(NPE, () -> ws.sendClose(NORMAL_CLOSURE, null));

            ws.abort();

            assertThrows(NPE, () -> ws.sendText(null, false));

            assertThrows(NPE, () -> ws.sendText(null, true));

            assertThrows(NPE, () -> ws.sendBinary(null, false));

            assertThrows(NPE, () -> ws.sendBinary(null, true));

            assertThrows(NPE, () -> ws.sendPing(null));

            assertThrows(NPE, () -> ws.sendPong(null));

            assertThrows(NPE, () -> ws.sendClose(NORMAL_CLOSURE, null));

        }

    }

    // TODO: request in onClose/onError

    // TODO: throw exception in onClose/onError

    // TODO: exception is thrown from request()

    @Test

    public void sendCloseCompleted() throws IOException {

        try (DummyWebSocketServer server = new DummyWebSocketServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            ws.sendClose(NORMAL_CLOSURE, "").join();

            assertTrue(ws.isOutputClosed());

            assertEquals(ws.getSubprotocol(), "");

            ws.request(1); // No exceptions must be thrown

        }

    }

    @Test

    public void sendClosePending() throws Exception {

        try (DummyWebSocketServer server = notReadingServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            ByteBuffer data = ByteBuffer.allocate(65536);

            for (int i = 0; ; i++) { // fill up the send buffer

                System.out.println("cycle #" + i);

                try {

                    ws.sendBinary(data, true).get(10, TimeUnit.SECONDS);

                    data.clear();

                } catch (TimeoutException e) {

                    break;

                }

            }

            CompletableFuture<WebSocket> cf = ws.sendClose(NORMAL_CLOSURE, "");

            // The output closes even if the Close message has not been sent

            assertFalse(cf.isDone());

            assertTrue(ws.isOutputClosed());

            assertEquals(ws.getSubprotocol(), "");

        }

    }

    /*

     * This server does not read from the wire, allowing its client to fill up

     * their send buffer. Used to test scenarios with outstanding send

     * operations.

     */

    private static DummyWebSocketServer notReadingServer() {

        return new DummyWebSocketServer() {

            @Override

            protected void serve(SocketChannel channel) throws IOException {

                try {

                    Thread.sleep(Long.MAX_VALUE);

                } catch (InterruptedException e) {

                    throw new IOException(e);

                }

            }

        };

    }

    public void abortPendingSendBinary() throws Exception {

        try (DummyWebSocketServer server = notReadingServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            ByteBuffer data = ByteBuffer.allocate(65536);

            CompletableFuture<WebSocket> cf = null;

            for (int i = 0; ; i++) {  // fill up the send buffer

                System.out.println("cycle #" + i);

                try {

                    cf = ws.sendBinary(data, true);

                    cf.get(10, TimeUnit.SECONDS);

                    data.clear();

                } catch (TimeoutException e) {

                    break;

                }

            }

            ws.abort();

            assertTrue(ws.isOutputClosed());

            assertTrue(ws.isInputClosed());

            assertCompletesExceptionally(IOException.class, cf);

        }

    }

    public void abortPendingSendText() throws Exception {

        try (DummyWebSocketServer server = notReadingServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            String data = stringWith2NBytes(32768);

            CompletableFuture<WebSocket> cf = null;

            for (int i = 0; ; i++) {  // fill up the send buffer

                System.out.println("cycle #" + i);

                try {

                    cf = ws.sendText(data, true);

                    cf.get(10, TimeUnit.SECONDS);

                } catch (TimeoutException e) {

                    break;

                }

            }

            ws.abort();

            assertTrue(ws.isOutputClosed());

            assertTrue(ws.isInputClosed());

            assertCompletesExceptionally(IOException.class, cf);

        }

    }

    private static String stringWith2NBytes(int n) {

        // -- Russian Alphabet (33 characters, 2 bytes per char) --

        char[] abc = {

                0x0410, 0x0411, 0x0412, 0x0413, 0x0414, 0x0415, 0x0401, 0x0416,

                0x0417, 0x0418, 0x0419, 0x041A, 0x041B, 0x041C, 0x041D, 0x041E,

                0x041F, 0x0420, 0x0421, 0x0422, 0x0423, 0x0424, 0x0425, 0x0426,

                0x0427, 0x0428, 0x0429, 0x042A, 0x042B, 0x042C, 0x042D, 0x042E,

                0x042F,

        };

        // repeat cyclically

        StringBuilder sb = new StringBuilder(n);

        for (int i = 0, j = 0; i < n; i++, j = (j + 1) % abc.length) {

            sb.append(abc[j]);

        }

        String s = sb.toString();

        assert s.length() == n && s.getBytes(StandardCharsets.UTF_8).length == 2 * n;

        return s;

    }

    @Test

    public void testIllegalArgument() throws IOException {

        try (DummyWebSocketServer server = new DummyWebSocketServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            assertCompletesExceptionally(IAE, ws.sendPing(ByteBuffer.allocate(126)));

            assertCompletesExceptionally(IAE, ws.sendPing(ByteBuffer.allocate(127)));

            assertCompletesExceptionally(IAE, ws.sendPing(ByteBuffer.allocate(128)));

            assertCompletesExceptionally(IAE, ws.sendPing(ByteBuffer.allocate(129)));

            assertCompletesExceptionally(IAE, ws.sendPing(ByteBuffer.allocate(256)));

            assertCompletesExceptionally(IAE, ws.sendPong(ByteBuffer.allocate(126)));

            assertCompletesExceptionally(IAE, ws.sendPong(ByteBuffer.allocate(127)));

            assertCompletesExceptionally(IAE, ws.sendPong(ByteBuffer.allocate(128)));

            assertCompletesExceptionally(IAE, ws.sendPong(ByteBuffer.allocate(129)));

            assertCompletesExceptionally(IAE, ws.sendPong(ByteBuffer.allocate(256)));

            assertCompletesExceptionally(IOE, ws.sendText(incompleteString(), true));

            assertCompletesExceptionally(IOE, ws.sendText(incompleteString(), false));

            assertCompletesExceptionally(IOE, ws.sendText(malformedString(), true));

            assertCompletesExceptionally(IOE, ws.sendText(malformedString(), false));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, stringWithNBytes(124)));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, stringWithNBytes(125)));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, stringWithNBytes(128)));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, stringWithNBytes(256)));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, stringWithNBytes(257)));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, stringWith2NBytes((123 / 2) + 1)));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, malformedString()));

            assertCompletesExceptionally(IAE, ws.sendClose(NORMAL_CLOSURE, incompleteString()));

            assertCompletesExceptionally(IAE, ws.sendClose(-2, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(-1, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(0, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(500, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(998, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(999, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1002, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1003, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1006, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1007, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1009, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1010, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1012, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1013, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(1015, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(5000, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(32768, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(65535, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(65536, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(Integer.MAX_VALUE, "a reason"));

            assertCompletesExceptionally(IAE, ws.sendClose(Integer.MIN_VALUE, "a reason"));

            assertThrows(IAE, () -> ws.request(Integer.MIN_VALUE));

            assertThrows(IAE, () -> ws.request(Long.MIN_VALUE));

            assertThrows(IAE, () -> ws.request(-1));

            assertThrows(IAE, () -> ws.request(0));

        }

    }

    private static String malformedString() {

        return new String(new char[]{0xDC00, 0xD800});

    }

    private static String incompleteString() {

        return new String(new char[]{0xD800});

    }

    private static String stringWithNBytes(int n) {

        char[] chars = new char[n];

        Arrays.fill(chars, 'A');

        return new String(chars);

    }

    @Test

    public void outstanding1() throws Exception {

        try (DummyWebSocketServer server = notReadingServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            ByteBuffer data = ByteBuffer.allocate(65536);

            for (int i = 0; ; i++) {  // fill up the send buffer

                System.out.println("cycle #" + i);

                try {

                    ws.sendBinary(data, true).get(10, TimeUnit.SECONDS);

                    data.clear();

                } catch (TimeoutException e) {

                    break;

                }

            }

            assertCompletesExceptionally(ISE, ws.sendBinary(ByteBuffer.allocate(0), true));

            assertCompletesExceptionally(ISE, ws.sendText("", true));

        }

    }

    @Test

    public void outstanding2() throws Exception {

        try (DummyWebSocketServer server = notReadingServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            CharBuffer data = CharBuffer.allocate(65536);

            for (int i = 0; ; i++) {  // fill up the send buffer

                System.out.println("cycle #" + i);

                try {

                    ws.sendText(data, true).get(10, TimeUnit.SECONDS);

                    data.clear();

                } catch (TimeoutException e) {

                    break;

                }

            }

            assertCompletesExceptionally(ISE, ws.sendText("", true));

            assertCompletesExceptionally(ISE, ws.sendBinary(ByteBuffer.allocate(0), true));

        }

    }

    @Test

    public void interleavingTypes1() throws IOException {

        try (DummyWebSocketServer server = new DummyWebSocketServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })

                    .join();

            ws.sendBinary(ByteBuffer.allocate(16), false).join();

            assertCompletesExceptionally(ISE, ws.sendText("text", false));

            assertCompletesExceptionally(ISE, ws.sendText("text", true));

        }

    }

    @Test

    public void interleavingTypes2() throws IOException {

        try (DummyWebSocketServer server = new DummyWebSocketServer()) {

            server.open();

            WebSocket ws = newHttpClient()

                    .newWebSocketBuilder()

                    .buildAsync(server.getURI(), new WebSocket.Listener() { })