import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';

void main() {
  testWidgets('first test', (tester) async {
    final myClient = _ExampleInputClient();

    await _runTest(tester, myClient);

    expect(myClient.performSelectorCalled, isTrue);
  });

  testWidgets('second test', (tester) async {
    final myClient = _ExampleInputClient();

    await _runTest(tester, myClient);

    expect(myClient.performSelectorCalled, isTrue);
  });
}

Future<void> _runTest(WidgetTester tester, TextInputClient client) async {
  debugDefaultTargetPlatformOverride = TargetPlatform.macOS;
  try {
    final focusNode = FocusNode();

    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Scaffold(
          body: Focus(
            focusNode: focusNode,
            autofocus: true,
            child: Container(),
          ),
        ),
      ),
    );

    /// Attach to the IME.
    final connection = TextInput.attach(client, const TextInputConfiguration());
    addTearDown(() {
      connection.close();
    });
    connection.show();

    // Press the left arrow, which should trigger a "moveLeft:" selector call.
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowLeft, platform: 'macos');
    await tester.pumpAndSettle();

    // Intercept the messages after the text input connection is established.
    // This will prevent the test text input from receiving the "clearClient" message,
    // to clear the keyboard handler.
    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
      SystemChannels.textInput,
      (MethodCall methodCall) async {
        return null;
      },
    );
  } finally {
    debugDefaultTargetPlatformOverride = null;
  }
}

/// A [TextInputClient] that reports whether the `performSelector` method was called.
class _ExampleInputClient with TextInputClient {
  bool get performSelectorCalled => _performSelectorCalled;
  bool _performSelectorCalled = false;

  @override
  AutofillScope? get currentAutofillScope => null;

  @override
  TextEditingValue? get currentTextEditingValue => _currentTextEditingValue;
  TextEditingValue _currentTextEditingValue = const TextEditingValue();

  @override
  void performSelector(String selectorName) {
    super.performSelector(selectorName);
    _performSelectorCalled = true;
  }

  @override
  void connectionClosed() {}

  @override
  void updateEditingValue(TextEditingValue value) {
    _currentTextEditingValue = value;
  }

  @override
  void performAction(TextInputAction action) {}

  @override
  void performPrivateCommand(String action, Map<String, dynamic> data) {}

  @override
  void showAutocorrectionPromptRect(int start, int end) {}

  @override
  void updateFloatingCursor(RawFloatingCursorPoint point) {}
}