import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:http/http.dart' as http;
import 'package:http/testing.dart';
import 'package:kouyu_english/core/ai_service.dart';
import 'package:kouyu_english/core/app_state.dart';
import 'package:kouyu_english/core/models.dart';
import 'package:kouyu_english/features/dialogue/dialogue_flow.dart';

void main() {
  testWidgets('sending a turn after an AI correction counts as assisted', (
    tester,
  ) async {
    // The page wires up recording and playback plugins that tests lack.
    final messenger = tester.binding.defaultBinaryMessenger;
    for (final name in const [
      'com.llfbandit.record/messages',
      'xyz.luan/audioplayers',
      'xyz.luan/audioplayers.global',
    ]) {
      messenger.setMockMethodCallHandler(
        MethodChannel(name),
        (_) async => null,
      );
    }
    messenger.setMockStreamHandler(
      const EventChannel('xyz.luan/audioplayers.global/events'),
      MockStreamHandler.inline(onListen: (_, _) {}),
    );
    // Each player also opens its own event channel under a random id.
    final reportError = FlutterError.onError;
    FlutterError.onError = (details) {
      if (details.exception is! MissingPluginException) {
        reportError?.call(details);
      }
    };
    addTearDown(() => FlutterError.onError = reportError);
    AiService.instance.setFallbackApiKey('test-key');
    final state = AppState()
      ..aiProvider = AiProviderType.compatible
      ..aiEndpoint = 'https://api.deepseek.com'
      ..aiModel = 'deepseek-flash';
    // A free scene only records items the learner has already been taught.
    state.mastery['A0-P01'] = MasteryItem(
      id: 'A0-P01',
      label: '介绍名字',
      status: MasteryStatus.recognize,
      evidence: const [],
      firstTaughtAt: DateTime.now().subtract(const Duration(days: 1)),
    );
    final check = jsonEncode({
      'schemaVersion': 'writing-feedback-1',
      'verdict': 'rewrite',
      'feedback': '介绍姓名正确，后半句有语法错误。',
      'suggestion': 'My name is Alex and I am happy.',
      'missing': ['I is 应为 I am'],
      'lessonId': 'dialogue-0',
    });
    final prompts = <String>[];
    http.Response reply(String content) => http.Response(
      jsonEncode({
        'choices': [
          {
            'message': {'content': content},
          },
        ],
      }),
      200,
      headers: {'content-type': 'application/json; charset=utf-8'},
    );

    await http.runWithClient(
      () async {
        await tester.pumpWidget(
          MaterialApp(
            home: Scaffold(
              body: DialoguePage(state: state, onFinished: (_) {}),
            ),
          ),
        );
        await tester.pump();
        await tester.enterText(
          find.byType(TextField),
          'My name is Alex and I is happy',
        );
        await tester.pump();
        final aiButton = find.text('发送前 AI 检查语法和拼写（可选）');
        await tester.ensureVisible(aiButton);
        await tester.tap(aiButton);
        await tester.runAsync(
          () => Future<void>.delayed(const Duration(milliseconds: 50)),
        );
        await tester.pump();

        expect(find.text('· I is 应为 I am'), findsOneWidget);
        expect(
          find.text('参考改正：My name is Alex and I am happy.'),
          findsOneWidget,
        );

        await tester.testTextInput.receiveAction(TextInputAction.done);
        await tester.runAsync(
          () => Future<void>.delayed(const Duration(milliseconds: 50)),
        );
        await tester.pump();
      },
      () => MockClient((request) async {
        final body = request.body;
        prompts.add(body);
        // The dialogue reply itself may fall back to the script.
        return reply(body.contains('writing-feedback-1') ? check : '{}');
      }),
    );

    expect(prompts.first, contains('I is happy'));
    expect(prompts.first, contains('dialogue-0'));
    final attempt = state.attemptEvidence.singleWhere(
      (entry) => entry.taskId.startsWith('dialogue-scene-'),
    );
    expect(attempt.itemId, 'A0-P01');
    expect(attempt.outcome, EvidenceKind.assisted);
    expect(state.sceneDialogueDraft?.usedHelp, isTrue);
  });
}