import 'dart:async';
import 'dart:typed_data';

import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:hepan_everyday/features/feedback/feedback_page.dart';
import 'package:hepan_everyday/features/feedback/feedback_submission.dart';

class RecordingSender implements FeedbackSender {
  final submissions = <FeedbackSubmission>[];
  Completer<void>? pending;
  bool fail = false;
  bool uncertain = false;

  @override
  Future<void> send(FeedbackSubmission submission) async {
    submissions.add(submission);
    if (pending != null) await pending!.future;
    if (uncertain) throw FeedbackDeliveryUncertain(submission.id);
    if (fail) throw const FeedbackException('网络暂时不可用，请重试');
  }
}

Future<void> reveal(
  WidgetTester tester,
  Finder target, {
  bool backwards = false,
}) async {
  await tester.scrollUntilVisible(
    target,
    backwards ? -250 : 250,
    scrollable: find.byType(Scrollable).first,
  );
  await tester.pump();
}

void main() {
  testWidgets('uncertain delivery retains original payload for status check', (
    tester,
  ) async {
    final sender = RecordingSender()..uncertain = true;
    await tester.pumpWidget(MaterialApp(home: FeedbackPage(sender: sender)));
    await tester.enterText(find.byKey(const Key('feedback-message')), '原来的反馈');
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    expect(find.text('提交成功'), findsNothing);
    expect(find.text('提交状态待确认'), findsOneWidget);
    expect(find.byKey(const Key('feedback-message')), findsNothing);
    expect(find.byKey(const Key('feedback-submit')), findsNothing);
    final original = sender.submissions.single;
    expect(
      tester
          .widget<SelectableText>(
            find.byKey(const Key('feedback-uncertain-id')),
          )
          .data,
      original.id,
    );
    sender.uncertain = false;
    await reveal(tester, find.byKey(const Key('feedback-check-original')));
    await tester.tap(find.byKey(const Key('feedback-check-original')));
    await tester.pumpAndSettle();
    expect(sender.submissions, hasLength(2));
    expect(identical(sender.submissions[0], sender.submissions[1]), isTrue);
    expect(find.text('提交成功'), findsOneWidget);
  });

  test('submission trims relevant fields and rejects whitespace', () {
    expect(
      () => FeedbackSubmission.problem(id: 'a', message: '  '),
      throwsA(isA<FeedbackException>()),
    );
    final problem = FeedbackSubmission.problem(
      id: 'a',
      message: '  页面建议  ',
      contact: '  ',
    );
    expect(problem.message, '页面建议');
    expect(problem.contact, isNull);
    expect(problem.school, isNull);
    final application = FeedbackSubmission.development(
      id: 'b',
      school: '  某大学  ',
      contact: ' 微信 abc ',
    );
    expect(application.school, '某大学');
    expect(application.contact, '微信 abc');
    expect(application.message, isNull);
    expect(application.attachments, isEmpty);
    expect(
      () => FeedbackSubmission.development(id: 'b', school: ' ', contact: 'x'),
      throwsA(isA<FeedbackException>()),
    );
    expect(
      () => FeedbackSubmission.development(id: 'b', school: 'x', contact: ' '),
      throwsA(isA<FeedbackException>()),
    );
  });

  test('attachment read stops at byte limit and sanitizes names', () async {
    var reads = 0;
    Stream<List<int>> oversized() async* {
      reads++;
      yield [1, 2, 3];
      reads++;
      yield [4, 5, 6];
      reads++;
      yield [7];
    }

    await expectLater(
      FeedbackAttachment.read(name: 'x.png', stream: oversized(), maxBytes: 4),
      throwsA(isA<FeedbackException>()),
    );
    expect(reads, 2);
    final attachment = await FeedbackAttachment.read(
      name: '../../unsafe\r\nname.PNG',
      stream: Stream.value([1, 2]),
    );
    expect(attachment.filename, 'unsafename.PNG');
    expect(attachment.contentType, 'image/png');
    await expectLater(
      FeedbackAttachment.read(name: 'x.exe', stream: Stream.value([1])),
      throwsA(isA<FeedbackException>()),
    );
  });

  test('submission enforces attachment count and total limits', () async {
    final file = await FeedbackAttachment.read(
      name: 'x.jpg',
      stream: Stream.value([1]),
    );
    expect(
      () => FeedbackSubmission.problem(
        id: 'a',
        message: 'x',
        attachments: [file, file, file, file],
      ),
      throwsA(isA<FeedbackException>()),
    );
    final large = await FeedbackAttachment.read(
      name: 'x.mp4',
      stream: Stream.value(Uint8List(8 * 1024 * 1024)),
    );
    expect(
      () => FeedbackSubmission.problem(
        id: 'a',
        message: 'x',
        attachments: [large, large, large],
      ),
      throwsA(isA<FeedbackException>()),
    );
  });

  testWidgets('problem requires message; contact is optional', (tester) async {
    final sender = RecordingSender();
    await tester.pumpWidget(MaterialApp(home: FeedbackPage(sender: sender)));
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    expect(find.text('请填写问题或建议'), findsOneWidget);
    expect(sender.submissions, isEmpty);
    await reveal(
      tester,
      find.byKey(const Key('feedback-message')),
      backwards: true,
    );
    await tester.enterText(find.byKey(const Key('feedback-message')), ' 建议内容 ');
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    expect(sender.submissions.single.message, '建议内容');
    expect(sender.submissions.single.contact, isNull);
    expect(find.text('提交成功'), findsOneWidget);
  });

  testWidgets('development requires school/contact and excludes hidden data', (
    tester,
  ) async {
    final sender = RecordingSender();
    await tester.pumpWidget(
      MaterialApp(
        home: FeedbackPage(
          sender: sender,
          pickAttachment: () async => FeedbackAttachment.read(
            name: 'hidden.png',
            stream: Stream.value([1, 2, 3]),
          ),
        ),
      ),
    );
    await tester.enterText(find.byKey(const Key('feedback-message')), '旧问题');
    await tester.ensureVisible(find.byKey(const Key('feedback-add-media')));
    await tester.tap(find.byKey(const Key('feedback-add-media')));
    await tester.pumpAndSettle();
    await reveal(tester, find.text('我要参与开发'), backwards: true);
    await tester.tap(find.text('我要参与开发'));
    await tester.pumpAndSettle();
    expect(find.byKey(const Key('feedback-message')), findsNothing);
    expect(find.byKey(const Key('feedback-add-media')), findsNothing);
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    expect(find.text('请填写学校'), findsOneWidget);
    expect(find.text('请填写联系方式'), findsOneWidget);
    await tester.enterText(find.byKey(const Key('feedback-school')), ' 某大学 ');
    await tester.enterText(
      find.byKey(const Key('feedback-contact')),
      ' QQ 123 ',
    );
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    final submission = sender.submissions.single;
    expect(submission.kind, FeedbackKind.development);
    expect(submission.school, '某大学');
    expect(submission.contact, 'QQ 123');
    expect(submission.message, isNull);
    expect(submission.attachments, isEmpty);
  });

  testWidgets(
    'pending send prevents duplicates; failure preserves data and retry ID',
    (tester) async {
      final sender = RecordingSender()
        ..pending = Completer<void>()
        ..fail = true;
      await tester.pumpWidget(MaterialApp(home: FeedbackPage(sender: sender)));
      await tester.enterText(find.byKey(const Key('feedback-message')), '问题');
      await reveal(tester, find.byKey(const Key('feedback-submit')));
      await tester.tap(find.byKey(const Key('feedback-submit')));
      await tester.pump();
      await tester.tap(find.byKey(const Key('feedback-submit')));
      await tester.pump();
      expect(sender.submissions, hasLength(1));
      expect(find.text('提交成功'), findsNothing);
      sender.pending!.complete();
      await tester.pumpAndSettle();
      expect(find.text('网络暂时不可用，请重试'), findsOneWidget);
      expect(find.text('问题'), findsOneWidget);
      sender
        ..pending = null
        ..fail = false;
      await reveal(tester, find.byKey(const Key('feedback-submit')));
      await tester.tap(find.byKey(const Key('feedback-submit')));
      await tester.pumpAndSettle();
      expect(sender.submissions, hasLength(2));
      expect(sender.submissions[0].id, sender.submissions[1].id);
      expect(find.text('提交成功'), findsOneWidget);
    },
  );

  testWidgets('editing a failed request starts a new submission ID', (
    tester,
  ) async {
    final sender = RecordingSender()..fail = true;
    await tester.pumpWidget(MaterialApp(home: FeedbackPage(sender: sender)));
    await tester.enterText(find.byKey(const Key('feedback-message')), '原来的问题');
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    await reveal(
      tester,
      find.byKey(const Key('feedback-message')),
      backwards: true,
    );
    await tester.enterText(find.byKey(const Key('feedback-message')), '更新的问题');
    sender.fail = false;
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    expect(sender.submissions[1].id, isNot(sender.submissions[0].id));
    expect(sender.submissions[1].message, '更新的问题');
  });

  testWidgets('unconfigured service gives honest error and preserves input', (
    tester,
  ) async {
    await tester.pumpWidget(const MaterialApp(home: FeedbackPage()));
    await tester.enterText(find.byKey(const Key('feedback-message')), '问题');
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    expect(find.text(UnconfiguredFeedbackSender.message), findsOneWidget);
    expect(find.text('提交成功'), findsNothing);
    expect(find.text('问题'), findsOneWidget);
  });

  testWidgets('selected media can be removed and survives send failure', (
    tester,
  ) async {
    final sender = RecordingSender()..fail = true;
    await tester.pumpWidget(
      MaterialApp(
        home: FeedbackPage(
          sender: sender,
          pickAttachment: () async => FeedbackAttachment.read(
            name: 'screen.png',
            stream: Stream.value([1, 2, 3]),
          ),
        ),
      ),
    );
    await tester.enterText(find.byKey(const Key('feedback-message')), '问题');
    await tester.ensureVisible(find.byKey(const Key('feedback-add-media')));
    await tester.tap(find.byKey(const Key('feedback-add-media')));
    await tester.pumpAndSettle();
    expect(find.text('screen.png'), findsOneWidget);
    await reveal(tester, find.byKey(const Key('feedback-submit')));
    await tester.tap(find.byKey(const Key('feedback-submit')));
    await tester.pumpAndSettle();
    expect(sender.submissions.single.attachments, hasLength(1));
    expect(find.text('screen.png'), findsOneWidget);
    await tester.ensureVisible(find.byTooltip('移除 screen.png'));
    await tester.tap(find.byTooltip('移除 screen.png'));
    await tester.pumpAndSettle();
    expect(find.text('screen.png'), findsNothing);
  });
}