/*

 * 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.

 */

import java.io.IOException;

import java.io.InputStream;

import java.io.PrintStream;

import java.net.Authenticator;

import java.net.InetSocketAddress;

import java.net.ProxySelector;

import java.net.URI;

import java.net.http.HttpClient;

import java.net.http.HttpClient.Redirect;

import java.net.http.HttpClient.Version;

import java.net.http.HttpRequest;

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.net.http.HttpResponse.BodySubscribers;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.time.Duration;

import java.util.Collections;

import java.util.List;

import java.util.concurrent.CopyOnWriteArrayList;

import java.util.concurrent.Flow;

import java.util.regex.Pattern;

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

/*

 * THE CONTENTS OF THIS FILE HAVE TO BE IN SYNC WITH THE EXAMPLES USED IN THE

 * JAVADOC.

 *

 * @test

 * @compile JavadocExamples.java

 */

public class JavadocExamples {

    HttpRequest request = null;

    HttpClient client = null;

    Pattern p = null;

    void fromHttpClientClasslevelDescription() throws Exception {

        //Synchronous Example

        HttpClient client = HttpClient.newBuilder()

                .version(Version.HTTP_1_1)

                .followRedirects(Redirect.NORMAL)

                .proxy(ProxySelector.of(new InetSocketAddress("proxy.example.com", 80)))

                .authenticator(Authenticator.getDefault())

                .build();

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

        System.out.println(response.statusCode());

        System.out.println(response.body());

        //Asynchronous Example

        HttpRequest request = HttpRequest.newBuilder()

                .uri(URI.create("https://foo.com/"))

                .timeout(Duration.ofMinutes(1))

                .header("Content-Type", "application/json")

                .POST(BodyPublishers.ofFile(Paths.get("file.json")))

                .build();

        client.sendAsync(request, BodyHandlers.ofString())

                .thenApply(HttpResponse::body)

                .thenAccept(System.out::println);

    }

    void fromHttpRequest() throws Exception {

        // HttpRequest class-level description

        HttpClient client = HttpClient.newHttpClient();

        HttpRequest request = HttpRequest.newBuilder()

                .uri(URI.create("http://foo.com/"))

                .build();

        client.sendAsync(request, BodyHandlers.ofString())

                .thenApply(HttpResponse::body)

                .thenAccept(System.out::println)

                .join();

        // HttpRequest.BodyPublishers class-level description

        // Request body from a String

        HttpRequest request1 = HttpRequest.newBuilder()

                .uri(URI.create("https://foo.com/"))

                .header("Content-Type", "text/plain; charset=UTF-8")

                .POST(BodyPublishers.ofString("some body text"))

                .build();

        // Request body from a File

        HttpRequest request2 = HttpRequest.newBuilder()

                .uri(URI.create("https://foo.com/"))

                .header("Content-Type", "application/json")

                .POST(BodyPublishers.ofFile(Paths.get("file.json")))

                .build();

        // Request body from a byte array

        HttpRequest request3 = HttpRequest.newBuilder()

                .uri(URI.create("https://foo.com/"))

                .POST(BodyPublishers.ofByteArray(new byte[] { /*...*/ }))

                .build();

    }

    void fromHttpResponse() throws Exception {

        // HttpResponse class-level description

        HttpResponse<String> response = client

                .send(request, BodyHandlers.ofString());

        // HttpResponse.BodyHandler class-level description

        HttpRequest request = HttpRequest.newBuilder()

                .uri(URI.create("http://www.foo.com/"))

                .build();

        client.sendAsync(request, BodyHandlers.ofFile(Paths.get("/tmp/f")))

                .thenApply(HttpResponse::body)

                .thenAccept(System.out::println);

        HttpRequest request1 = HttpRequest.newBuilder()

                .uri(URI.create("http://www.foo.com/"))

                .build();

        BodyHandler<Path> bodyHandler = (info) -> info.statusCode() == 200

                ? BodySubscribers.ofFile(Paths.get("/tmp/f"))

                : BodySubscribers.replacing(Paths.get("/NULL"));

        client.sendAsync(request, bodyHandler)

                .thenApply(HttpResponse::body)

                .thenAccept(System.out::println);

        // HttpResponse.BodyHandlers class-level description

        // Receives the response body as a String

        HttpResponse<String> response1 = client

                .send(request, BodyHandlers.ofString());

        // Receives the response body as a file

        HttpResponse<Path> response2 = client

                .send(request, BodyHandlers.ofFile(Paths.get("example.html")));

        // Receives the response body as an InputStream

        HttpResponse<InputStream> respons3 = client

                .send(request, BodyHandlers.ofInputStream());

        // Discards the response body

        HttpResponse<Void> respons4 = client

                .send(request, BodyHandlers.discarding());

        // HttpResponse.BodySubscribers class-level description

        // Streams the response body to a File

        HttpResponse<byte[]> response5 = client

                .send(request, responseInfo -> BodySubscribers.ofByteArray());

        // Accumulates the response body and returns it as a byte[]

        HttpResponse<byte[]> response6 = client

                .send(request, responseInfo -> BodySubscribers.ofByteArray());

        // Discards the response body

        HttpResponse<Void> response7 = client

                .send(request, responseInfo -> BodySubscribers.discarding());

        // Accumulates the response body as a String then maps it to its bytes

        HttpResponse<byte[]> response8 = client

                .send(request, responseInfo ->

                        BodySubscribers.mapping(BodySubscribers.ofString(UTF_8), String::getBytes));

    }

    /**

     * @apiNote This method can be used as an adapter between a {@code

     * BodySubscriber} and a text based {@code Flow.Subscriber} that parses

     * text line by line.

     *

     * <p> For example:

     * <pre> {@code  // A PrintSubscriber that implements Flow.Subscriber<String>

     *  // and print lines received by onNext() on System.out

     *  PrintSubscriber subscriber = new PrintSubscriber(System.out);

     *  client.sendAsync(request, BodyHandlers.fromLineSubscriber(subscriber))

     *      .thenApply(HttpResponse::statusCode)

     *      .thenAccept((status) -> {

     *          if (status != 200) {

     *              System.err.printf("ERROR: %d status received%n", status);

     *          }

     *      }); }</pre>

     */

    void fromLineSubscriber1() {

         // A PrintSubscriber that implements Flow.Subscriber<String>

         // and print lines received by onNext() on System.out

         PrintSubscriber subscriber = new PrintSubscriber(System.out);

         client.sendAsync(request, BodyHandlers.fromLineSubscriber(subscriber))

                 .thenApply(HttpResponse::statusCode)

                 .thenAccept((status) -> {

                     if (status != 200) {

                         System.err.printf("ERROR: %d status received%n", status);

                     }

                 });

    }

    /**

     * @apiNote This method can be used as an adapter between a {@code

     * BodySubscriber} and a text based {@code Flow.Subscriber} that parses

     * text line by line.

     *

     * <p> For example:

     * <pre> {@code  // A LineParserSubscriber that implements Flow.Subscriber<String>

     *  // and accumulates lines that match a particular pattern

     *  Pattern pattern = ...;

     *  LineParserSubscriber subscriber = new LineParserSubscriber(pattern);

     *  HttpResponse<List<String>> response = client.send(request,

     *      BodyHandlers.fromLineSubscriber(subscriber, s -> s.getMatchingLines(), "\n"));

     *  if (response.statusCode() != 200) {

     *      System.err.printf("ERROR: %d status received%n", response.statusCode());

     *  } }</pre>

     *

     */

    void fromLineSubscriber2() throws IOException, InterruptedException {

        // A LineParserSubscriber that implements Flow.Subscriber<String>

        // and accumulates lines that match a particular pattern

        Pattern pattern = p;

        LineParserSubscriber subscriber = new LineParserSubscriber(pattern);

        HttpResponse<List<String>> response = client.send(request,

                BodyHandlers.fromLineSubscriber(subscriber, s -> s.getMatchingLines(), "\n"));

        if (response.statusCode() != 200) {

            System.err.printf("ERROR: %d status received%n", response.statusCode());

        }

    }

    static final class PrintSubscriber implements Flow.Subscriber<String> {

        final PrintStream out;

        PrintSubscriber(PrintStream out) {

            this.out = out;

        }

        @Override

        public void onSubscribe(Flow.Subscription subscription) {

            subscription.request(Long.MAX_VALUE);

        }

        @Override

        public void onNext(String item) {

            out.println(item);

        }

        @Override

        public void onError(Throwable throwable) {

            throwable.printStackTrace();

        }

        @Override

        public void onComplete() {

        }

    }

    static final class LineParserSubscriber implements Flow.Subscriber<String> {

        final Pattern pattern;

        final CopyOnWriteArrayList<String> matches = new CopyOnWriteArrayList<>();

        LineParserSubscriber(Pattern pattern) {

            this.pattern = pattern;

        }

        @Override

        public void onSubscribe(Flow.Subscription subscription) {

            subscription.request(Long.MAX_VALUE);

        }

        @Override

        public void onNext(String item) {

            if (pattern.matcher(item).matches()) {

                matches.add(item);

            }

        }

        @Override

        public void onError(Throwable throwable) {

            throwable.printStackTrace();

        }

        @Override

        public void onComplete() {

        }

        public List<String> getMatchingLines() {

            return Collections.unmodifiableList(matches);

        }

    }

}