import 'dart:convert';

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

void main() {
  Future<(WritingAiFeedback?, String)> check(Map<String, dynamic> reply) async {
    AiService.instance.setFallbackApiKey('test-key');
    var prompt = '';
    final content = jsonEncode(reply);
    final result = await http.runWithClient(
      () => AiService.instance.answerFeedback(
        provider: AiProviderType.compatible,
        endpoint: 'https://api.deepseek.com',
        model: 'deepseek-flash',
        answerId: 'A0-P12',
        target: "I'm from …",
        taskPrompt: '告诉对方你来自哪里。',
        answer: 'I am from Chna',
      ),
      () => MockClient((request) async {
        final body = jsonDecode(request.body) as Map<String, dynamic>;
        prompt = jsonEncode(body);
        return http.Response(
          jsonEncode({
            'choices': [
              {
                'message': {'content': content},
              },
            ],
          }),
          200,
          headers: {'content-type': 'application/json; charset=utf-8'},
        );
      }),
    );
    return (result, prompt);
  }

  test('review AI check returns spelling corrections for the item', () async {
    final (feedback, prompt) = await check({
      'schemaVersion': 'writing-feedback-1',
      'verdict': 'rewrite',
      'feedback': '句型正确，有一个拼写错误。',
      'suggestion': 'I am from China.',
      'missing': ['Chna 拼写应为 China'],
      'lessonId': 'A0-P12',
    });

    expect(prompt, contains('spelling'));
    expect(prompt, contains('I am from Chna'));
    expect(feedback, isNotNull);
    expect(feedback!.verdict, 'rewrite');
    expect(feedback.suggestion, 'I am from China.');
    expect(feedback.missing, ['Chna 拼写应为 China']);
  });

  test('review AI check rejects feedback for a different item', () async {
    final (feedback, _) = await check({
      'schemaVersion': 'writing-feedback-1',
      'verdict': 'accepted',
      'feedback': '很好。',
      'suggestion': null,
      'missing': <String>[],
      'lessonId': 'A0-P01',
    });

    expect(feedback, isNull);
  });

  test('review AI check is skipped without a configured provider', () async {
    final feedback = await AiService.instance.answerFeedback(
      provider: AiProviderType.mock,
      endpoint: '',
      model: '',
      answerId: 'A0-P12',
      target: "I'm from …",
      taskPrompt: '告诉对方你来自哪里。',
      answer: 'I am from China',
    );

    expect(feedback, isNull);
  });

  testWidgets('finishing after an AI correction counts as assisted', (
    tester,
  ) async {
    AiService.instance.setFallbackApiKey('test-key');
    final state = AppState()
      ..aiProvider = AiProviderType.compatible
      ..aiEndpoint = 'https://api.deepseek.com'
      ..aiModel = 'deepseek-flash';
    state.reviewQueue.add(
      ReviewItem(
        id: 'A0-P12',
        target: "I'm from …",
        prompt: '告诉对方你来自哪里。',
        hint: "I'm from China.",
        dueAt: DateTime.now().subtract(const Duration(hours: 1)),
        skill: '回忆表达',
      ),
    );
    final content = jsonEncode({
      'schemaVersion': 'writing-feedback-1',
      'verdict': 'rewrite',
      'feedback': '句型正确，有一个拼写错误。',
      'suggestion': 'I am from China.',
      'missing': ['Chna 拼写应为 China'],
      'lessonId': 'A0-P12',
    });
    await http.runWithClient(
      () async {
        await tester.pumpWidget(
          MaterialApp(
            home: Scaffold(
              body: ReviewPage(
                state: state,
                onFinished: () {},
                onOpenAdaptiveLesson: () {},
              ),
            ),
          ),
        );
        await tester.enterText(find.byType(TextField), 'I am from Chna');
        await tester.pump();
        final aiButton = find.text('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();
      },
      () => MockClient(
        (request) async => http.Response(
          jsonEncode({
            'choices': [
              {
                'message': {'content': content},
              },
            ],
          }),
          200,
          headers: {'content-type': 'application/json; charset=utf-8'},
        ),
      ),
    );

    expect(find.text('· Chna 拼写应为 China'), findsOneWidget);
    expect(find.text('参考改正：I am from China.'), findsOneWidget);
    final submit = find.text('带提示完成');
    expect(submit, findsOneWidget);
    await tester.ensureVisible(submit);
    await tester.tap(submit);
    await tester.pump();

    expect(state.attemptEvidence.single.outcome, EvidenceKind.assisted);
    expect(state.attemptEvidence.single.assisted, isTrue);
  });
}