// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This test is run using `flutter drive` by the CI (see /script/tool/README.md
// in this repository for details on driving that tooling manually), but can
// also be run using `flutter test` directly during development.

import 'dart:async';
import 'dart:convert';
import 'dart:io';
// TODO(a14n): remove this import once Flutter 3.1 or later reaches stable (including flutter/flutter#104231)
// ignore: unnecessary_import
import 'dart:typed_data';

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:integration_test/integration_test.dart';
import 'package:webview_flutter_android/src/instance_manager.dart';
import 'package:webview_flutter_android/src/weak_reference_utils.dart';
import 'package:webview_flutter_android/webview_android.dart';
import 'package:webview_flutter_android/webview_surface_android.dart';
import 'package:webview_flutter_android_example/navigation_decision.dart';
import 'package:webview_flutter_android_example/navigation_request.dart';
import 'package:webview_flutter_android_example/web_view.dart';
import 'package:webview_flutter_platform_interface/webview_flutter_platform_interface.dart';

Future<void> main() async {
  IntegrationTestWidgetsFlutterBinding.ensureInitialized();

  final HttpServer server = await HttpServer.bind(InternetAddress.anyIPv4, 0);
  server.forEach((HttpRequest request) {
    if (request.uri.path == '/hello.txt') {
      request.response.writeln('Hello, world.');
    } else if (request.uri.path == '/secondary.txt') {
      request.response.writeln('How are you today?');
    } else if (request.uri.path == '/headers') {
      request.response.writeln('${request.headers}');
    } else if (request.uri.path == '/favicon.ico') {
      request.response.statusCode = HttpStatus.notFound;
    } else {
      fail('unexpected request: ${request.method} ${request.uri}');
    }
    request.response.close();
  });
  final String prefixUrl = 'http://${server.address.address}:${server.port}';
  final String primaryUrl = '$prefixUrl/hello.txt';
  final String secondaryUrl = '$prefixUrl/secondary.txt';
  final String headersUrl = '$prefixUrl/headers';

  testWidgets('initialUrl', (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    final Completer<void> pageFinishedCompleter = Completer<void>();
    await tester.pumpWidget(
      MaterialApp(
        home: Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: primaryUrl,
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            onPageFinished: pageFinishedCompleter.complete,
          ),
        ),
      ),
    );

    final WebViewController controller = await controllerCompleter.future;
    await pageFinishedCompleter.future;

    final String? currentUrl = await controller.currentUrl();
    expect(currentUrl, primaryUrl);
  });

  testWidgets('loadUrl', (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    final StreamController<String> pageLoads = StreamController<String>();
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: GlobalKey(),
          initialUrl: primaryUrl,
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter.complete(controller);
          },
          onPageFinished: (String url) {
            pageLoads.add(url);
          },
        ),
      ),
    );
    final WebViewController controller = await controllerCompleter.future;

    await controller.loadUrl(secondaryUrl);
    await expectLater(
      pageLoads.stream.firstWhere((String url) => url == secondaryUrl),
      completion(secondaryUrl),
    );
  });

  testWidgets(
      'withWeakRefenceTo allows encapsulating class to be garbage collected',
      (WidgetTester tester) async {
    final Completer<int> gcCompleter = Completer<int>();
    final InstanceManager instanceManager = InstanceManager(
      onWeakReferenceRemoved: gcCompleter.complete,
    );

    ClassWithCallbackClass? instance = ClassWithCallbackClass();
    instanceManager.addHostCreatedInstance(instance.callbackClass, 0);
    instance = null;

    // Force garbage collection.
    await IntegrationTestWidgetsFlutterBinding.instance
        .watchPerformance(() async {
      await tester.pumpAndSettle();
    });

    final int gcIdentifier = await gcCompleter.future;
    expect(gcIdentifier, 0);
  }, timeout: const Timeout(Duration(seconds: 10)));

  testWidgets('evaluateJavascript', (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: GlobalKey(),
          initialUrl: primaryUrl,
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter.complete(controller);
          },
          javascriptMode: JavascriptMode.unrestricted,
        ),
      ),
    );
    final WebViewController controller = await controllerCompleter.future;
    final String result = await controller.evaluateJavascript('1 + 1');
    expect(result, equals('2'));
  });

  testWidgets('loadUrl with headers', (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    final StreamController<String> pageStarts = StreamController<String>();
    final StreamController<String> pageLoads = StreamController<String>();
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: GlobalKey(),
          initialUrl: primaryUrl,
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter.complete(controller);
          },
          javascriptMode: JavascriptMode.unrestricted,
          onPageStarted: (String url) {
            pageStarts.add(url);
          },
          onPageFinished: (String url) {
            pageLoads.add(url);
          },
        ),
      ),
    );
    final WebViewController controller = await controllerCompleter.future;
    final Map<String, String> headers = <String, String>{
      'test_header': 'flutter_test_header'
    };
    await controller.loadUrl(headersUrl, headers: headers);
    final String? currentUrl = await controller.currentUrl();
    expect(currentUrl, headersUrl);

    await pageStarts.stream.firstWhere((String url) => url == currentUrl);
    await pageLoads.stream.firstWhere((String url) => url == currentUrl);

    final String content = await controller
        .runJavascriptReturningResult('document.documentElement.innerText');
    expect(content.contains('flutter_test_header'), isTrue);
  });

  testWidgets('JavascriptChannel', (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    final Completer<void> pageStarted = Completer<void>();
    final Completer<void> pageLoaded = Completer<void>();
    final Completer<String> channelCompleter = Completer<String>();
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: GlobalKey(),
          // This is the data URL for: '<!DOCTYPE html>'
          initialUrl:
              'data:text/html;charset=utf-8;base64,PCFET0NUWVBFIGh0bWw+',
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter.complete(controller);
          },
          javascriptMode: JavascriptMode.unrestricted,
          javascriptChannels: <JavascriptChannel>{
            JavascriptChannel(
              name: 'Echo',
              onMessageReceived: (JavascriptMessage message) {
                channelCompleter.complete(message.message);
              },
            ),
          },
          onPageStarted: (String url) {
            pageStarted.complete(null);
          },
          onPageFinished: (String url) {
            pageLoaded.complete(null);
          },
        ),
      ),
    );
    final WebViewController controller = await controllerCompleter.future;
    await pageStarted.future;
    await pageLoaded.future;

    expect(channelCompleter.isCompleted, isFalse);
    await controller.runJavascript('Echo.postMessage("hello");');

    await expectLater(channelCompleter.future, completion('hello'));
  });

  testWidgets('resize webview', (WidgetTester tester) async {
    final Completer<void> initialResizeCompleter = Completer<void>();
    final Completer<void> buttonTapResizeCompleter = Completer<void>();
    final Completer<void> onPageFinished = Completer<void>();

    bool resizeButtonTapped = false;
    await tester.pumpWidget(ResizableWebView(
      onResize: (_) {
        if (resizeButtonTapped) {
          buttonTapResizeCompleter.complete();
        } else {
          initialResizeCompleter.complete();
        }
      },
      onPageFinished: () => onPageFinished.complete(),
    ));
    await onPageFinished.future;
    // Wait for a potential call to resize after page is loaded.
    await initialResizeCompleter.future.timeout(
      const Duration(seconds: 3),
      onTimeout: () => null,
    );

    resizeButtonTapped = true;
    await tester.tap(find.byKey(const ValueKey<String>('resizeButton')));
    await tester.pumpAndSettle();
    expect(buttonTapResizeCompleter.future, completes);
  });

  testWidgets('set custom userAgent', (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter1 =
        Completer<WebViewController>();
    final GlobalKey _globalKey = GlobalKey();
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: _globalKey,
          initialUrl: 'about:blank',
          javascriptMode: JavascriptMode.unrestricted,
          userAgent: 'Custom_User_Agent1',
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter1.complete(controller);
          },
        ),
      ),
    );
    final WebViewController controller1 = await controllerCompleter1.future;
    final String customUserAgent1 = await _getUserAgent(controller1);
    expect(customUserAgent1, 'Custom_User_Agent1');
    // rebuild the WebView with a different user agent.
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: _globalKey,
          initialUrl: 'about:blank',
          javascriptMode: JavascriptMode.unrestricted,
          userAgent: 'Custom_User_Agent2',
        ),
      ),
    );

    final String customUserAgent2 = await _getUserAgent(controller1);
    expect(customUserAgent2, 'Custom_User_Agent2');
  });

  testWidgets('use default platform userAgent after webView is rebuilt',
      (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    final GlobalKey _globalKey = GlobalKey();
    // Build the webView with no user agent to get the default platform user agent.
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: _globalKey,
          initialUrl: primaryUrl,
          javascriptMode: JavascriptMode.unrestricted,
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter.complete(controller);
          },
        ),
      ),
    );
    final WebViewController controller = await controllerCompleter.future;
    final String defaultPlatformUserAgent = await _getUserAgent(controller);
    // rebuild the WebView with a custom user agent.
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: _globalKey,
          initialUrl: 'about:blank',
          javascriptMode: JavascriptMode.unrestricted,
          userAgent: 'Custom_User_Agent',
        ),
      ),
    );
    final String customUserAgent = await _getUserAgent(controller);
    expect(customUserAgent, 'Custom_User_Agent');
    // rebuilds the WebView with no user agent.
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: _globalKey,
          initialUrl: 'about:blank',
          javascriptMode: JavascriptMode.unrestricted,
        ),
      ),
    );

    final String customUserAgent2 = await _getUserAgent(controller);
    expect(customUserAgent2, defaultPlatformUserAgent);
  });

  group('Video playback policy', () {
    late String videoTestBase64;
    setUpAll(() async {
      final ByteData videoData =
          await rootBundle.load('assets/sample_video.mp4');
      final String base64VideoData =
          base64Encode(Uint8List.view(videoData.buffer));
      final String videoTest = '''
        <!DOCTYPE html><html>
        <head><title>Video auto play</title>
          <script type="text/javascript">
            function play() {
              var video = document.getElementById("video");
              video.play();
              video.addEventListener('timeupdate', videoTimeUpdateHandler, false);
            }
            function videoTimeUpdateHandler(e) {
              var video = document.getElementById("video");
              VideoTestTime.postMessage(video.currentTime);
            }
            function isPaused() {
              var video = document.getElementById("video");
              return video.paused;
            }
            function isFullScreen() {
              var video = document.getElementById("video");
              return video.webkitDisplayingFullscreen;
            }
          </script>
        </head>
        <body onload="play();">
        <video controls playsinline autoplay id="video">
          <source src="data:video/mp4;charset=utf-8;base64,$base64VideoData">
        </video>
        </body>
        </html>
      ''';
      videoTestBase64 = base64Encode(const Utf8Encoder().convert(videoTest));
    });

    testWidgets('Auto media playback', (WidgetTester tester) async {
      Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      Completer<void> pageLoaded = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: 'data:text/html;charset=utf-8;base64,$videoTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
            initialMediaPlaybackPolicy: AutoMediaPlaybackPolicy.always_allow,
          ),
        ),
      );
      WebViewController controller = await controllerCompleter.future;
      await pageLoaded.future;

      String isPaused =
          await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(false));

      controllerCompleter = Completer<WebViewController>();
      pageLoaded = Completer<void>();

      // We change the key to re-create a new webview as we change the initialMediaPlaybackPolicy
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: 'data:text/html;charset=utf-8;base64,$videoTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
          ),
        ),
      );

      controller = await controllerCompleter.future;
      await pageLoaded.future;

      isPaused = await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(true));
    });

    testWidgets('Changes to initialMediaPlaybackPolicy are ignored',
        (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      Completer<void> pageLoaded = Completer<void>();

      final GlobalKey key = GlobalKey();
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: key,
            initialUrl: 'data:text/html;charset=utf-8;base64,$videoTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
            initialMediaPlaybackPolicy: AutoMediaPlaybackPolicy.always_allow,
          ),
        ),
      );
      final WebViewController controller = await controllerCompleter.future;
      await pageLoaded.future;

      String isPaused =
          await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(false));

      pageLoaded = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: key,
            initialUrl: 'data:text/html;charset=utf-8;base64,$videoTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
          ),
        ),
      );

      await controller.reload();

      await pageLoaded.future;

      isPaused = await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(false));
    });

    testWidgets('Video plays inline when allowsInlineMediaPlayback is true',
        (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      final Completer<void> pageLoaded = Completer<void>();
      final Completer<void> videoPlaying = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            initialUrl: 'data:text/html;charset=utf-8;base64,$videoTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            javascriptChannels: <JavascriptChannel>{
              JavascriptChannel(
                name: 'VideoTestTime',
                onMessageReceived: (JavascriptMessage message) {
                  final double currentTime = double.parse(message.message);
                  // Let it play for at least 1 second to make sure the related video's properties are set.
                  if (currentTime > 1 && !videoPlaying.isCompleted) {
                    videoPlaying.complete(null);
                  }
                },
              ),
            },
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
            initialMediaPlaybackPolicy: AutoMediaPlaybackPolicy.always_allow,
            allowsInlineMediaPlayback: true,
          ),
        ),
      );
      final WebViewController controller = await controllerCompleter.future;
      await pageLoaded.future;

      // Pump once to trigger the video play.
      await tester.pump();

      // Makes sure we get the correct event that indicates the video is actually playing.
      await videoPlaying.future;

      final String fullScreen =
          await controller.runJavascriptReturningResult('isFullScreen();');
      expect(fullScreen, _webviewBool(false));
    });
  });

  group('Audio playback policy', () {
    late String audioTestBase64;
    setUpAll(() async {
      final ByteData audioData =
          await rootBundle.load('assets/sample_audio.ogg');
      final String base64AudioData =
          base64Encode(Uint8List.view(audioData.buffer));
      final String audioTest = '''
        <!DOCTYPE html><html>
        <head><title>Audio auto play</title>
          <script type="text/javascript">
            function play() {
              var audio = document.getElementById("audio");
              audio.play();
            }
            function isPaused() {
              var audio = document.getElementById("audio");
              return audio.paused;
            }
          </script>
        </head>
        <body onload="play();">
        <audio controls id="audio">
          <source src="data:audio/ogg;charset=utf-8;base64,$base64AudioData">
        </audio>
        </body>
        </html>
      ''';
      audioTestBase64 = base64Encode(const Utf8Encoder().convert(audioTest));
    });

    testWidgets('Auto media playback', (WidgetTester tester) async {
      Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      Completer<void> pageStarted = Completer<void>();
      Completer<void> pageLoaded = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: 'data:text/html;charset=utf-8;base64,$audioTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageStarted: (String url) {
              pageStarted.complete(null);
            },
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
            initialMediaPlaybackPolicy: AutoMediaPlaybackPolicy.always_allow,
          ),
        ),
      );
      WebViewController controller = await controllerCompleter.future;
      await pageStarted.future;
      await pageLoaded.future;

      String isPaused =
          await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(false));

      controllerCompleter = Completer<WebViewController>();
      pageStarted = Completer<void>();
      pageLoaded = Completer<void>();

      // We change the key to re-create a new webview as we change the initialMediaPlaybackPolicy
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: 'data:text/html;charset=utf-8;base64,$audioTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageStarted: (String url) {
              pageStarted.complete(null);
            },
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
          ),
        ),
      );

      controller = await controllerCompleter.future;
      await pageStarted.future;
      await pageLoaded.future;

      isPaused = await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(true));
    });

    testWidgets('Changes to initialMediaPlaybackPolicy are ignored',
        (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      Completer<void> pageStarted = Completer<void>();
      Completer<void> pageLoaded = Completer<void>();

      final GlobalKey key = GlobalKey();
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: key,
            initialUrl: 'data:text/html;charset=utf-8;base64,$audioTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageStarted: (String url) {
              pageStarted.complete(null);
            },
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
            initialMediaPlaybackPolicy: AutoMediaPlaybackPolicy.always_allow,
          ),
        ),
      );
      final WebViewController controller = await controllerCompleter.future;
      await pageStarted.future;
      await pageLoaded.future;

      String isPaused =
          await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(false));

      pageStarted = Completer<void>();
      pageLoaded = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: key,
            initialUrl: 'data:text/html;charset=utf-8;base64,$audioTestBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageStarted: (String url) {
              pageStarted.complete(null);
            },
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
          ),
        ),
      );

      await controller.reload();

      await pageStarted.future;
      await pageLoaded.future;

      isPaused = await controller.runJavascriptReturningResult('isPaused();');
      expect(isPaused, _webviewBool(false));
    });
  });

  testWidgets('getTitle', (WidgetTester tester) async {
    const String getTitleTest = '''
        <!DOCTYPE html><html>
        <head><title>Some title</title>
        </head>
        <body>
        </body>
        </html>
      ''';
    final String getTitleTestBase64 =
        base64Encode(const Utf8Encoder().convert(getTitleTest));
    final Completer<void> pageStarted = Completer<void>();
    final Completer<void> pageLoaded = Completer<void>();
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();

    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          initialUrl: 'data:text/html;charset=utf-8;base64,$getTitleTestBase64',
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter.complete(controller);
          },
          onPageStarted: (String url) {
            pageStarted.complete(null);
          },
          onPageFinished: (String url) {
            pageLoaded.complete(null);
          },
        ),
      ),
    );

    final WebViewController controller = await controllerCompleter.future;
    await pageStarted.future;
    await pageLoaded.future;

    final String? title = await controller.getTitle();
    expect(title, 'Some title');
  });

  group('Programmatic Scroll', () {
    testWidgets('setAndGetScrollPosition', (WidgetTester tester) async {
      const String scrollTestPage = '''
        <!DOCTYPE html>
        <html>
          <head>
            <style>
              body {
                height: 100%;
                width: 100%;
              }
              #container{
                width:5000px;
                height:5000px;
            }
            </style>
          </head>
          <body>
            <div id="container"/>
          </body>
        </html>
      ''';

      final String scrollTestPageBase64 =
          base64Encode(const Utf8Encoder().convert(scrollTestPage));

      final Completer<void> pageLoaded = Completer<void>();
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            initialUrl:
                'data:text/html;charset=utf-8;base64,$scrollTestPageBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
          ),
        ),
      );

      final WebViewController controller = await controllerCompleter.future;
      await pageLoaded.future;

      await tester.pumpAndSettle(const Duration(seconds: 3));

      int scrollPosX = await controller.getScrollX();
      int scrollPosY = await controller.getScrollY();

      // Check scrollTo()
      const int X_SCROLL = 123;
      const int Y_SCROLL = 321;
      // Get the initial position; this ensures that scrollTo is actually
      // changing something, but also gives the native view's scroll position
      // time to settle.
      expect(scrollPosX, isNot(X_SCROLL));
      expect(scrollPosX, isNot(Y_SCROLL));

      await controller.scrollTo(X_SCROLL, Y_SCROLL);
      scrollPosX = await controller.getScrollX();
      scrollPosY = await controller.getScrollY();
      expect(scrollPosX, X_SCROLL);
      expect(scrollPosY, Y_SCROLL);

      // Check scrollBy() (on top of scrollTo())
      await controller.scrollBy(X_SCROLL, Y_SCROLL);
      scrollPosX = await controller.getScrollX();
      scrollPosY = await controller.getScrollY();
      expect(scrollPosX, X_SCROLL * 2);
      expect(scrollPosY, Y_SCROLL * 2);
    });
  });

  group('SurfaceAndroidWebView', () {
    setUpAll(() {
      WebView.platform = SurfaceAndroidWebView();
    });

    tearDownAll(() {
      WebView.platform = AndroidWebView();
    });

    testWidgets('setAndGetScrollPosition', (WidgetTester tester) async {
      const String scrollTestPage = '''
        <!DOCTYPE html>
        <html>
          <head>
            <style>
              body {
                height: 100%;
                width: 100%;
              }
              #container{
                width:5000px;
                height:5000px;
            }
            </style>
          </head>
          <body>
            <div id="container"/>
          </body>
        </html>
      ''';

      final String scrollTestPageBase64 =
          base64Encode(const Utf8Encoder().convert(scrollTestPage));

      final Completer<void> pageLoaded = Completer<void>();
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            initialUrl:
                'data:text/html;charset=utf-8;base64,$scrollTestPageBase64',
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            onPageFinished: (String url) {
              pageLoaded.complete(null);
            },
          ),
        ),
      );

      final WebViewController controller = await controllerCompleter.future;
      await pageLoaded.future;

      await tester.pumpAndSettle(const Duration(seconds: 3));

      // Check scrollTo()
      const int X_SCROLL = 123;
      const int Y_SCROLL = 321;

      await controller.scrollTo(X_SCROLL, Y_SCROLL);
      int scrollPosX = await controller.getScrollX();
      int scrollPosY = await controller.getScrollY();
      expect(X_SCROLL, scrollPosX);
      expect(Y_SCROLL, scrollPosY);

      // Check scrollBy() (on top of scrollTo())
      await controller.scrollBy(X_SCROLL, Y_SCROLL);
      scrollPosX = await controller.getScrollX();
      scrollPosY = await controller.getScrollY();
      expect(X_SCROLL * 2, scrollPosX);
      expect(Y_SCROLL * 2, scrollPosY);
    });

    testWidgets('inputs are scrolled into view when focused',
        (WidgetTester tester) async {
      const String scrollTestPage = '''
        <!DOCTYPE html>
        <html>
          <head>
            <style>
              input {
                margin: 10000px 0;
              }
              #viewport {
                position: fixed;
                top:0;
                bottom:0;
                left:0;
                right:0;
              }
            </style>
          </head>
          <body>
            <div id="viewport"></div>
            <input type="text" id="inputEl">
          </body>
        </html>
      ''';

      final String scrollTestPageBase64 =
          base64Encode(const Utf8Encoder().convert(scrollTestPage));

      final Completer<void> pageLoaded = Completer<void>();
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();

      await tester.runAsync(() async {
        await tester.pumpWidget(
          Directionality(
            textDirection: TextDirection.ltr,
            child: SizedBox(
              width: 200,
              height: 200,
              child: WebView(
                initialUrl:
                    'data:text/html;charset=utf-8;base64,$scrollTestPageBase64',
                onWebViewCreated: (WebViewController controller) {
                  controllerCompleter.complete(controller);
                },
                onPageFinished: (String url) {
                  pageLoaded.complete(null);
                },
                javascriptMode: JavascriptMode.unrestricted,
              ),
            ),
          ),
        );
        await Future<void>.delayed(const Duration(milliseconds: 20));
        await tester.pump();
      });

      final WebViewController controller = await controllerCompleter.future;
      await pageLoaded.future;
      final String viewportRectJSON = await _runJavaScriptReturningResult(
          controller, 'JSON.stringify(viewport.getBoundingClientRect())');
      final Map<String, dynamic> viewportRectRelativeToViewport =
          jsonDecode(viewportRectJSON) as Map<String, dynamic>;

      // Check that the input is originally outside of the viewport.

      final String initialInputClientRectJSON =
          await _runJavaScriptReturningResult(
              controller, 'JSON.stringify(inputEl.getBoundingClientRect())');
      final Map<String, dynamic> initialInputClientRectRelativeToViewport =
          jsonDecode(initialInputClientRectJSON) as Map<String, dynamic>;

      expect(
          initialInputClientRectRelativeToViewport['bottom'] <=
              viewportRectRelativeToViewport['bottom'],
          isFalse);

      await controller.runJavascript('inputEl.focus()');

      // Check that focusing the input brought it into view.

      final String lastInputClientRectJSON =
          await _runJavaScriptReturningResult(
              controller, 'JSON.stringify(inputEl.getBoundingClientRect())');
      final Map<String, dynamic> lastInputClientRectRelativeToViewport =
          jsonDecode(lastInputClientRectJSON) as Map<String, dynamic>;

      expect(
          lastInputClientRectRelativeToViewport['top'] >=
              viewportRectRelativeToViewport['top'],
          isTrue);
      expect(
          lastInputClientRectRelativeToViewport['bottom'] <=
              viewportRectRelativeToViewport['bottom'],
          isTrue);

      expect(
          lastInputClientRectRelativeToViewport['left'] >=
              viewportRectRelativeToViewport['left'],
          isTrue);
      expect(
          lastInputClientRectRelativeToViewport['right'] <=
              viewportRectRelativeToViewport['right'],
          isTrue);
    });
  });

  group('NavigationDelegate', () {
    const String blankPage = '<!DOCTYPE html><head></head><body></body></html>';
    final String blankPageEncoded = 'data:text/html;charset=utf-8;base64,'
        '${base64Encode(const Utf8Encoder().convert(blankPage))}';

    testWidgets('can allow requests', (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      final StreamController<String> pageLoads =
          StreamController<String>.broadcast();
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: blankPageEncoded,
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            navigationDelegate: (NavigationRequest request) {
              return (request.url.contains('youtube.com'))
                  ? NavigationDecision.prevent
                  : NavigationDecision.navigate;
            },
            onPageFinished: (String url) => pageLoads.add(url),
          ),
        ),
      );

      await pageLoads.stream.first; // Wait for initial page load.
      final WebViewController controller = await controllerCompleter.future;
      await controller.runJavascript('location.href = "$secondaryUrl"');

      await pageLoads.stream.first; // Wait for the next page load.
      final String? currentUrl = await controller.currentUrl();
      expect(currentUrl, secondaryUrl);
    });

    testWidgets('onWebResourceError', (WidgetTester tester) async {
      final Completer<WebResourceError> errorCompleter =
          Completer<WebResourceError>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: 'https://www.notawebsite..com',
            onWebResourceError: (WebResourceError error) {
              errorCompleter.complete(error);
            },
          ),
        ),
      );

      final WebResourceError error = await errorCompleter.future;
      expect(error, isNotNull);

      expect(error.errorType, isNotNull);
      expect(
          error.failingUrl?.startsWith('https://www.notawebsite..com'), isTrue);
    });

    testWidgets('onWebResourceError is not called with valid url',
        (WidgetTester tester) async {
      final Completer<WebResourceError> errorCompleter =
          Completer<WebResourceError>();
      final Completer<void> pageFinishCompleter = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl:
                'data:text/html;charset=utf-8;base64,PCFET0NUWVBFIGh0bWw+',
            onWebResourceError: (WebResourceError error) {
              errorCompleter.complete(error);
            },
            onPageFinished: (_) => pageFinishCompleter.complete(),
          ),
        ),
      );

      expect(errorCompleter.future, doesNotComplete);
      await pageFinishCompleter.future;
    });

    testWidgets(
      'onWebResourceError only called for main frame',
      (WidgetTester tester) async {
        const String iframeTest = '''
        <!DOCTYPE html>
        <html>
        <head>
          <title>WebResourceError test</title>
        </head>
        <body>
          <iframe src="https://notawebsite..com"></iframe>
        </body>
        </html>
       ''';
        final String iframeTestBase64 =
            base64Encode(const Utf8Encoder().convert(iframeTest));

        final Completer<WebResourceError> errorCompleter =
            Completer<WebResourceError>();
        final Completer<void> pageFinishCompleter = Completer<void>();

        await tester.pumpWidget(
          Directionality(
            textDirection: TextDirection.ltr,
            child: WebView(
              key: GlobalKey(),
              initialUrl:
                  'data:text/html;charset=utf-8;base64,$iframeTestBase64',
              onWebResourceError: (WebResourceError error) {
                errorCompleter.complete(error);
              },
              onPageFinished: (_) => pageFinishCompleter.complete(),
            ),
          ),
        );

        expect(errorCompleter.future, doesNotComplete);
        await pageFinishCompleter.future;
      },
    );

    testWidgets('can block requests', (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      final StreamController<String> pageLoads =
          StreamController<String>.broadcast();
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: blankPageEncoded,
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            navigationDelegate: (NavigationRequest request) {
              return (request.url.contains('youtube.com'))
                  ? NavigationDecision.prevent
                  : NavigationDecision.navigate;
            },
            onPageFinished: (String url) => pageLoads.add(url),
          ),
        ),
      );

      await pageLoads.stream.first; // Wait for initial page load.
      final WebViewController controller = await controllerCompleter.future;
      await controller
          .runJavascript('location.href = "https://www.youtube.com/"');

      // There should never be any second page load, since our new URL is
      // blocked. Still wait for a potential page change for some time in order
      // to give the test a chance to fail.
      await pageLoads.stream.first
          .timeout(const Duration(milliseconds: 500), onTimeout: () => '');
      final String? currentUrl = await controller.currentUrl();
      expect(currentUrl, isNot(contains('youtube.com')));
    });

    testWidgets('supports asynchronous decisions', (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      final StreamController<String> pageLoads =
          StreamController<String>.broadcast();
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: blankPageEncoded,
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            navigationDelegate: (NavigationRequest request) async {
              NavigationDecision decision = NavigationDecision.prevent;
              decision = await Future<NavigationDecision>.delayed(
                  const Duration(milliseconds: 10),
                  () => NavigationDecision.navigate);
              return decision;
            },
            onPageFinished: (String url) => pageLoads.add(url),
          ),
        ),
      );

      await pageLoads.stream.first; // Wait for initial page load.
      final WebViewController controller = await controllerCompleter.future;
      await controller.runJavascript('location.href = "$secondaryUrl"');

      await pageLoads.stream.first; // Wait for second page to load.
      final String? currentUrl = await controller.currentUrl();
      expect(currentUrl, secondaryUrl);
    });
  });

  testWidgets('launches with gestureNavigationEnabled on iOS',
      (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: SizedBox(
          width: 400,
          height: 300,
          child: WebView(
            key: GlobalKey(),
            initialUrl: primaryUrl,
            gestureNavigationEnabled: true,
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
          ),
        ),
      ),
    );
    final WebViewController controller = await controllerCompleter.future;
    final String? currentUrl = await controller.currentUrl();
    expect(currentUrl, primaryUrl);
  });

  testWidgets('target _blank opens in same window',
      (WidgetTester tester) async {
    final Completer<WebViewController> controllerCompleter =
        Completer<WebViewController>();
    final Completer<void> pageLoaded = Completer<void>();
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: WebView(
          key: GlobalKey(),
          onWebViewCreated: (WebViewController controller) {
            controllerCompleter.complete(controller);
          },
          javascriptMode: JavascriptMode.unrestricted,
          onPageFinished: (String url) {
            pageLoaded.complete(null);
          },
        ),
      ),
    );
    final WebViewController controller = await controllerCompleter.future;
    await controller.runJavascript('window.open("$primaryUrl", "_blank")');
    await pageLoaded.future;
    final String? currentUrl = await controller.currentUrl();
    expect(currentUrl, primaryUrl);
  });

  testWidgets(
    'can open new window and go back',
    (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      Completer<void> pageLoaded = Completer<void>();
      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            onPageFinished: (String url) {
              pageLoaded.complete();
            },
            initialUrl: primaryUrl,
          ),
        ),
      );
      final WebViewController controller = await controllerCompleter.future;
      expect(controller.currentUrl(), completion(primaryUrl));
      await pageLoaded.future;
      pageLoaded = Completer<void>();

      await controller.runJavascript('window.open("$secondaryUrl")');
      await pageLoaded.future;
      pageLoaded = Completer<void>();
      expect(controller.currentUrl(), completion(secondaryUrl));

      expect(controller.canGoBack(), completion(true));
      await controller.goBack();
      await pageLoaded.future;
      await expectLater(controller.currentUrl(), completion(primaryUrl));
    },
  );

  testWidgets(
    'JavaScript does not run in parent window',
    (WidgetTester tester) async {
      const String iframe = '''
        <!DOCTYPE html>
        <script>
          window.onload = () => {
            window.open(`javascript:
              var elem = document.createElement("p");
              elem.innerHTML = "<b>Executed JS in parent origin: " + window.location.origin + "</b>";
              document.body.append(elem);
            `);
          };
        </script>
      ''';
      final String iframeTestBase64 =
          base64Encode(const Utf8Encoder().convert(iframe));

      final String openWindowTest = '''
        <!DOCTYPE html>
        <html>
        <head>
          <title>XSS test</title>
        </head>
        <body>
          <iframe
            onload="window.iframeLoaded = true;"
            src="data:text/html;charset=utf-8;base64,$iframeTestBase64"></iframe>
        </body>
        </html>
      ''';
      final String openWindowTestBase64 =
          base64Encode(const Utf8Encoder().convert(openWindowTest));
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();
      final Completer<void> pageLoadCompleter = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
            javascriptMode: JavascriptMode.unrestricted,
            initialUrl:
                'data:text/html;charset=utf-8;base64,$openWindowTestBase64',
            onPageFinished: (String url) {
              pageLoadCompleter.complete();
            },
          ),
        ),
      );

      final WebViewController controller = await controllerCompleter.future;
      await pageLoadCompleter.future;

      final String iframeLoaded =
          await controller.runJavascriptReturningResult('iframeLoaded');
      expect(iframeLoaded, 'true');

      final String elementText = await controller.runJavascriptReturningResult(
        'document.querySelector("p") && document.querySelector("p").textContent',
      );
      expect(elementText, 'null');
    },
  );

  testWidgets(
    'clearCache should clear local storage',
    (WidgetTester tester) async {
      final Completer<WebViewController> controllerCompleter =
          Completer<WebViewController>();

      Completer<void> pageLoadCompleter = Completer<void>();

      await tester.pumpWidget(
        Directionality(
          textDirection: TextDirection.ltr,
          child: WebView(
            key: GlobalKey(),
            initialUrl: primaryUrl,
            javascriptMode: JavascriptMode.unrestricted,
            onPageFinished: (_) => pageLoadCompleter.complete(),
            onWebViewCreated: (WebViewController controller) {
              controllerCompleter.complete(controller);
            },
          ),
        ),
      );

      await pageLoadCompleter.future;
      pageLoadCompleter = Completer<void>();

      final WebViewController controller = await controllerCompleter.future;
      await controller.runJavascript('localStorage.setItem("myCat", "Tom");');
      final String myCatItem = await controller.runJavascriptReturningResult(
        'localStorage.getItem("myCat");',
      );
      expect(myCatItem, '"Tom"');

      await controller.clearCache();
      await pageLoadCompleter.future;

      final String nullItem = await controller.runJavascriptReturningResult(
        'localStorage.getItem("myCat");',
      );
      expect(nullItem, 'null');
    },
  );
}

// JavaScript booleans evaluate to different string values on Android and iOS.
// This utility method returns the string boolean value of the current platform.
String _webviewBool(bool value) {
  if (defaultTargetPlatform == TargetPlatform.iOS) {
    return value ? '1' : '0';
  }
  return value ? 'true' : 'false';
}

/// Returns the value used for the HTTP User-Agent: request header in subsequent HTTP requests.
Future<String> _getUserAgent(WebViewController controller) async {
  return _runJavaScriptReturningResult(controller, 'navigator.userAgent;');
}

Future<String> _runJavaScriptReturningResult(
  WebViewController controller,
  String js,
) async {
  return jsonDecode(await controller.runJavascriptReturningResult(js))
      as String;
}

class ResizableWebView extends StatefulWidget {
  const ResizableWebView({
    Key? key,
    required this.onResize,
    required this.onPageFinished,
  }) : super(key: key);

  final JavascriptMessageHandler onResize;
  final VoidCallback onPageFinished;

  @override
  State<StatefulWidget> createState() => ResizableWebViewState();
}

class ResizableWebViewState extends State<ResizableWebView> {
  double webViewWidth = 200;
  double webViewHeight = 200;

  static const String resizePage = '''
        <!DOCTYPE html><html>
        <head><title>Resize test</title>
          <script type="text/javascript">
            function onResize() {
              Resize.postMessage("resize");
            }
            function onLoad() {
              window.onresize = onResize;
            }
          </script>
        </head>
        <body onload="onLoad();" bgColor="blue">
        </body>
        </html>
      ''';

  @override
  Widget build(BuildContext context) {
    final String resizeTestBase64 =
        base64Encode(const Utf8Encoder().convert(resizePage));
    return Directionality(
      textDirection: TextDirection.ltr,
      child: Column(
        children: <Widget>[
          SizedBox(
            width: webViewWidth,
            height: webViewHeight,
            child: WebView(
              initialUrl:
                  'data:text/html;charset=utf-8;base64,$resizeTestBase64',
              javascriptChannels: <JavascriptChannel>{
                JavascriptChannel(
                  name: 'Resize',
                  onMessageReceived: widget.onResize,
                ),
              },
              onPageFinished: (_) => widget.onPageFinished(),
              javascriptMode: JavascriptMode.unrestricted,
            ),
          ),
          TextButton(
            key: const Key('resizeButton'),
            onPressed: () {
              setState(() {
                webViewWidth += 100.0;
                webViewHeight += 100.0;
              });
            },
            child: const Text('ResizeButton'),
          ),
        ],
      ),
    );
  }
}

class CopyableObjectWithCallback with Copyable {
  CopyableObjectWithCallback(this.callback);

  final VoidCallback callback;

  @override
  CopyableObjectWithCallback copy() {
    return CopyableObjectWithCallback(callback);
  }
}

class ClassWithCallbackClass {
  ClassWithCallbackClass() {
    callbackClass = CopyableObjectWithCallback(
      withWeakRefenceTo(
        this,
        (WeakReference<ClassWithCallbackClass> weakReference) {
          return () {
            // Weak reference to `this` in callback.
            // ignore: unnecessary_statements
            weakReference;
          };
        },
      ),
    );
  }

  late final CopyableObjectWithCallback callbackClass;
}