/*

 * 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 that our client deals correctly with servers that

 *          close the connection right after sending the last byte.

 * @library /lib/testlibrary http2/server

 * @build jdk.testlibrary.SimpleSSLContext HttpServerAdapters EncodedCharsInURI

 * @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 ServerCloseTest

 */

//*        -Djdk.internal.httpclient.debug=true

import jdk.testlibrary.SimpleSSLContext;

import org.testng.annotations.AfterClass;

import org.testng.annotations.AfterTest;

import org.testng.annotations.BeforeTest;

import org.testng.annotations.DataProvider;

import org.testng.annotations.Test;

import javax.net.ServerSocketFactory;

import javax.net.ssl.SSLContext;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.OutputStreamWriter;

import java.io.PrintWriter;

import java.io.Writer;

import java.net.InetAddress;

import java.net.InetSocketAddress;

import java.net.ServerSocket;

import java.net.Socket;

import java.net.URI;

import java.net.http.HttpClient;

import java.net.http.HttpRequest;

import java.net.http.HttpRequest.BodyPublisher;

import java.net.http.HttpRequest.BodyPublishers;

import java.net.http.HttpResponse;

import java.net.http.HttpResponse.BodyHandler;

import java.net.http.HttpResponse.BodyHandlers;

import java.util.List;

import java.util.Locale;

import java.util.StringTokenizer;

import java.util.concurrent.CompletableFuture;

import java.util.concurrent.ConcurrentHashMap;

import java.util.concurrent.ConcurrentLinkedQueue;

import java.util.concurrent.ConcurrentMap;

import java.util.concurrent.Executor;

import java.util.concurrent.Executors;

import java.util.concurrent.atomic.AtomicLong;

import static java.lang.System.out;

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

public class ServerCloseTest implements HttpServerAdapters {

    SSLContext sslContext;

    DummyServer    httpDummyServer;    // HTTP/1.1    [ 2 servers ]

    DummyServer    httpsDummyServer;   // HTTPS/1.1

    String httpDummy;

    String httpsDummy;

    static final int ITERATION_COUNT = 3;

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

    static final Executor executor = new TestExecutor(Executors.newCachedThreadPool());

    static final ConcurrentMap<String, Throwable> FAILURES = new ConcurrentHashMap<>();

    static volatile boolean tasksFailed;

    static final AtomicLong serverCount = new AtomicLong();

    static final AtomicLong clientCount = new AtomicLong();

    static final long start = System.nanoTime();

    public static String now() {

        long now = System.nanoTime() - start;

        long secs = now / 1000_000_000;

        long mill = (now % 1000_000_000) / 1000_000;

        long nan = now % 1000_000;

        return String.format("[%d s, %d ms, %d ns] ", secs, mill, nan);

    }

    private volatile HttpClient sharedClient;

    static class TestExecutor implements Executor {

        final AtomicLong tasks = new AtomicLong();

        Executor executor;

        TestExecutor(Executor executor) {

            this.executor = executor;

        }

        @Override

        public void execute(Runnable command) {

            long id = tasks.incrementAndGet();

            executor.execute(() -> {

                try {

                    command.run();

                } catch (Throwable t) {

                    tasksFailed = true;

                    System.out.printf(now() + "Task %s failed: %s%n", id, t);

                    System.err.printf(now() + "Task %s failed: %s%n", id, t);

                    FAILURES.putIfAbsent("Task " + id, t);

                    throw t;

                }

            });

        }

    }

    @AfterClass

    static final void printFailedTests() {

        out.println("\n=========================");

        try {

            out.printf("%n%sCreated %d servers and %d clients%n",

                    now(), serverCount.get(), clientCount.get());

            if (FAILURES.isEmpty()) return;

            out.println("Failed tests: ");

            FAILURES.entrySet().forEach((e) -> {

                out.printf("\t%s: %s%n", e.getKey(), e.getValue());

                e.getValue().printStackTrace(out);

            });

            if (tasksFailed) {

                System.out.println("WARNING: Some tasks failed");

            }

        } finally {

            out.println("\n=========================\n");

        }

    }

    private String[] uris() {

        return new String[] {

                httpDummy,

                httpsDummy,

        };

    }

    @DataProvider(name = "servers")

    public Object[][] noThrows() {

        String[] uris = uris();

        Object[][] result = new Object[uris.length * 2][];

        //Object[][] result = new Object[uris.length][];

        int i = 0;

        for (boolean sameClient : List.of(false, true)) {

            //if (!sameClient) continue;

            for (String uri: uris()) {

                result[i++] = new Object[] {uri, sameClient};

            }

        }

        assert i == uris.length * 2;

        // assert i == uris.length ;

        return result;

    }

    private HttpClient makeNewClient() {

        clientCount.incrementAndGet();

        return HttpClient.newBuilder()

                .executor(executor)

                .sslContext(sslContext)

                .build();

    }

    HttpClient newHttpClient(boolean share) {

        if (!share) return makeNewClient();

        HttpClient shared = sharedClient;

        if (shared != null) return shared;

        synchronized (this) {

            shared = sharedClient;

            if (shared == null) {

                shared = sharedClient = makeNewClient();

            }

            return shared;

        }

    }

    final String ENCODED = "/01%252F03/";

    @Test(dataProvider = "servers")

    public void testServerClose(String uri, boolean sameClient) {

        HttpClient client = null;

        out.printf("%n%s testServerClose(%s, %b)%n", now(), uri, sameClient);

        uri = uri + ENCODED;

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

            if (!sameClient || client == null)

                client = newHttpClient(sameClient);

            BodyPublisher bodyPublisher = BodyPublishers.ofString(uri);

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

                    .POST(bodyPublisher)

                    .build();

            BodyHandler<String> handler = BodyHandlers.ofString();

            HttpClient c = client;

            CompletableFuture<HttpResponse<String>> responseCF = c.sendAsync(req, handler);

            // retry POST if needed   #### Replace with exceptionallyCompose

            responseCF = responseCF.handle((r,t) ->

                    t == null ? CompletableFuture.completedFuture(r)

                            : c.sendAsync(req, handler)).thenCompose(x -> x);

            HttpResponse<String> response = responseCF.join();

            String body = response.body();

            if (!uri.contains(body)) {

                System.err.println("Test failed: " + response);

                throw new RuntimeException(uri + " doesn't contain '" + body + "'");

            } else {

                System.out.println("Found expected " + body + " in " + uri);

            }

        }

    }

    @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);

        // DummyServer

        httpDummyServer = DummyServer.create(sa);

        httpsDummyServer = DummyServer.create(sa, sslContext);

        httpDummy = "http://" + httpDummyServer.serverAuthority() + "/http1/dummy/x";

        httpsDummy = "https://" + httpsDummyServer.serverAuthority() + "/https1/dummy/x";

        serverCount.addAndGet(2);

        httpDummyServer.start();

        httpsDummyServer.start();

    }

    @AfterTest

    public void teardown() throws Exception {

        sharedClient = null;

        httpDummyServer.stopServer();

        httpsDummyServer.stopServer();

    }

    static class DummyServer extends Thread {

        final ServerSocket ss;

        final boolean secure;

        ConcurrentLinkedQueue<Socket> connections = new ConcurrentLinkedQueue<>();

        volatile boolean stopped;

        DummyServer(ServerSocket ss, boolean secure) {

            super("DummyServer[" + ss.getLocalPort()+"]");

            this.secure = secure;

            this.ss = ss;

        }

        // This is a bit shaky. It doesn't handle continuation

        // lines, but our client shouldn't send any.

        // Read a line from the input stream, swallowing the final

        // \r\n sequence. Stops at the first \n, doesn't complain

        // if it wasn't preceded by '\r'.

        //

        String readLine(InputStream r) throws IOException {

            StringBuilder b = new StringBuilder();

            int c;

            while ((c = r.read()) != -1) {

                if (c == '\n') break;

                b.appendCodePoint(c);

            }

            if (b.codePointAt(b.length() -1) == '\r') {

                b.delete(b.length() -1, b.length());

            }

            return b.toString();

        }

        @Override

        public void run() {

            try {

                while(!stopped) {

                    Socket clientConnection = ss.accept();

                    connections.add(clientConnection);

                    System.out.println(now() + getName() + ": Client accepted");

                    StringBuilder headers = new StringBuilder();

                    Socket targetConnection = null;

                    InputStream  ccis = clientConnection.getInputStream();

                    OutputStream ccos = clientConnection.getOutputStream();

                    Writer w = new OutputStreamWriter(

                            clientConnection.getOutputStream(), "UTF-8");

                    PrintWriter pw = new PrintWriter(w);

                    System.out.println(now() + getName() + ": Reading request line");

                    String requestLine = readLine(ccis);

                    System.out.println(now() + getName() + ": Request line: " + requestLine);

                    StringTokenizer tokenizer = new StringTokenizer(requestLine);

                    String method = tokenizer.nextToken();

                    assert method.equalsIgnoreCase("POST")

                            || method.equalsIgnoreCase("GET");

                    String path = tokenizer.nextToken();

                    URI uri;

                    try {

                        String hostport = serverAuthority();

                        uri = new URI((secure ? "https" : "http") +"://" + hostport + path);

                    } catch (Throwable x) {

                        System.err.printf("Bad target address: \"%s\" in \"%s\"%n",

                                path, requestLine);

                        clientConnection.close();

                        continue;

                    }

                    // Read all headers until we find the empty line that

                    // signals the end of all headers.

                    String line = requestLine;

                    while (!line.equals("")) {

                        System.out.println(now() + getName() + ": Reading header: "

                                + (line = readLine(ccis)));

                        headers.append(line).append("\r\n");

                    }

                    StringBuilder response = new StringBuilder();

                    int index = headers.toString()

                            .toLowerCase(Locale.US)

                            .indexOf("content-length: ");

                    byte[] b = uri.toString().getBytes(UTF_8);

                    if (index >= 0) {

                        index = index + "content-length: ".length();

                        String cl = headers.toString().substring(index);

                        StringTokenizer tk = new StringTokenizer(cl);

                        int len = Integer.parseInt(tk.nextToken());

                        assert len < b.length * 2;

                        System.out.println(now() + getName()

                                + ": received body: "

                                + new String(ccis.readNBytes(len), UTF_8));

                    }

                    System.out.println(now()

                            + getName() + ": sending back " + uri);

                    response.append("HTTP/1.1 200 OK\r\nContent-Length: ")

                            .append(b.length)

                            .append("\r\n\r\n");

                    // Then send the 200 OK response to the client

                    System.out.println(now() + getName() + ": Sending "

                            + response);

                    pw.print(response);

                    pw.flush();

                    ccos.write(b);

                    ccos.flush();

                    ccos.close();

                    connections.remove(clientConnection);

                    clientConnection.close();

                }

            } catch (Throwable t) {

                if (!stopped) {

                    System.out.println(now() + getName() + ": failed: " + t);

                    t.printStackTrace();

                    try {

                        stopServer();

                    } catch (Throwable e) {

                    }

                }

            } finally {

                System.out.println(now() + getName() + ": exiting");

            }

        }

        void close(Socket s) {

            try {

                s.close();

            } catch(Throwable t) {

            }

        }

        public void stopServer() throws IOException {

            stopped = true;

            ss.close();

            connections.forEach(this::close);

        }

        public String serverAuthority() {

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

                    + ss.getLocalPort();

        }

        static DummyServer create(InetSocketAddress sa) throws IOException {

            ServerSocket ss = ServerSocketFactory.getDefault()

                    .createServerSocket(sa.getPort(), -1, sa.getAddress());

            return  new DummyServer(ss, false);

        }

        static DummyServer create(InetSocketAddress sa, SSLContext sslContext) throws IOException {

            ServerSocket ss = sslContext.getServerSocketFactory()

                    .createServerSocket(sa.getPort(), -1, sa.getAddress());

            return new DummyServer(ss, true);

        }

    }

}