import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:patbond_flutter/core/network/api_exception.dart';
import 'package:patbond_flutter/core/theme/app_theme.dart';
import 'package:patbond_flutter/core/widgets/feed_skeleton.dart';
import 'package:patbond_flutter/core/widgets/inline_error_banner.dart';
import 'package:patbond_flutter/core/widgets/post_card.dart';
import 'package:patbond_flutter/features/community/community_controller.dart';
import 'package:patbond_flutter/features/community/community_interaction_analytics.dart';
import 'package:patbond_flutter/features/community/community_models.dart';
import 'package:patbond_flutter/features/community/feed_analytics.dart';
import 'package:patbond_flutter/features/home/home_page.dart';
import 'package:patbond_flutter/state/app_state.dart';

import '../../helpers/community_test_helpers.dart';

/// 短卡（纯文字）便于视口内多卡曝光断言；内容带 id 便于查重。
FeedCard textCard(String id) => FeedCard.fromJson({
  ...sampleFeedCardJson(id: id),
  'coverImage': null,
  'mediaCount': 0,
  'title': null,
  'contentPreview': '动态内容 $id',
});

FeedCard degradedCard(String id) => FeedCard.fromJson({
  ...sampleFeedCardJson(id: id),
  'coverImage': null,
  'mediaCount': 0,
  'title': null,
  'contentPreview': '动态内容 $id',
  'author': sampleAuthorJson(nickname: null, avatarUrl: null),
});

void main() {
  late FakeCommunityRepository repository;
  late CommunityController controller;
  late List<(String, Map<String, dynamic>?)> events;
  late FeedAnalytics analytics;
  late int createTaps;
  late List<String> openedPosts;

  setUp(() {
    repository = FakeCommunityRepository();
    events = [];
    controller = CommunityController(
      repository: repository,
      interactionAnalytics: CommunityInteractionAnalytics(
        (name, [props]) async => events.add((name, props)),
      ),
    );
    analytics = FeedAnalytics(
      (name, [props]) async => events.add((name, props)),
    );
    createTaps = 0;
    openedPosts = [];
  });

  List<Map<String, dynamic>?> eventsNamed(String name) =>
      events.where((e) => e.$1 == name).map((e) => e.$2).toList();

  Future<void> pumpHome(WidgetTester tester, {bool isActive = true}) {
    return tester.pumpWidget(
      MaterialApp(
        theme: buildAppTheme(),
        home: Scaffold(
          body: HomePage(
            appState: AppState(),
            communityController: controller,
            feedAnalytics: analytics,
            isActive: isActive,
            onOpenServices: (_) {},
            onOpenCreate: () => createTaps++,
            onOpenPost: openedPosts.add,
          ),
        ),
      ),
    );
  }

  // 页面纵向主列表（story 环是嵌套的水平 ListView，取 first 即外层）。
  Finder list() => find.byType(ListView).first;

  testWidgets('四态 · loading：首载渲染 3 张骨架屏', (tester) async {
    final completer = Completer<CursorPage<FeedCard>>();
    repository.onFeed = (_, _) => completer.future;

    await pumpHome(tester);
    await tester.pump();

    // 首载骨架连排 3 张（列表懒加载，视口内至少 1 张被实例化）。
    expect(find.byType(FeedSkeleton), findsAtLeastNWidgets(1));

    completer.complete(feedPage(const []));
    await tester.pumpAndSettle();
    expect(find.byType(FeedSkeleton), findsNothing);
  });

  testWidgets('四态 · empty：空态插画 + 「发布第一条」CTA 去创作', (tester) async {
    repository.onFeed = (_, _) async => feedPage(const []);

    await pumpHome(tester);
    await tester.pumpAndSettle();

    expect(find.text('还没有动态'), findsOneWidget);
    await tester.drag(list(), const Offset(0, -300));
    await tester.pump();
    await tester.tap(find.text('发布第一条'));
    expect(createTaps, 1);
  });

  testWidgets('四态 · error：横幅 + 重试恢复 ready，feed_load_failed 上报', (tester) async {
    var attempts = 0;
    repository.onFeed = (_, _) async {
      attempts += 1;
      if (attempts == 1) throw const ApiNetworkException();
      return feedPage([textCard('p-1')]);
    };

    await pumpHome(tester);
    await tester.pumpAndSettle();

    expect(find.byType(InlineErrorBanner), findsOneWidget);
    expect(find.text('网络异常，请检查网络后重试'), findsOneWidget);
    expect(eventsNamed('feed_load_failed'), [
      {
        'feedTab': 'home',
        'loadType': 'refresh',
        'failureReason': 'network_error',
      },
    ]);

    await tester.drag(list(), const Offset(0, -200));
    await tester.pump();
    await tester.tap(find.text('重试'));
    await tester.pumpAndSettle();

    expect(find.byType(InlineErrorBanner), findsNothing);
    expect(find.text('动态内容 p-1'), findsOneWidget);
  });

  testWidgets('四态 · ready：卡片列表 + 降级作者「宠友」占位', (tester) async {
    repository.onFeed = (_, _) async =>
        feedPage([textCard('p-1'), degradedCard('p-2')]);

    await pumpHome(tester);
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -400));
    await tester.pump();

    expect(find.byType(PostCard), findsNWidgets(2));
    expect(find.text('毛毛的铲屎官'), findsOneWidget);
    expect(find.text('宠友'), findsOneWidget);
  });

  testWidgets('翻页：触底携游标加载下一页，不丢不重，到底显「没有更多了」', (tester) async {
    final page2 = Completer<CursorPage<FeedCard>>();
    repository.onFeed = (_, cursor) async {
      if (cursor == null) {
        return feedPage(
          [textCard('p-1'), textCard('p-2')],
          nextCursor: 'c1',
          hasMore: true,
        );
      }
      return page2.future;
    };

    await pumpHome(tester);
    await tester.pumpAndSettle();

    // 触底：尾部 loading 转圈。
    await tester.drag(list(), const Offset(0, -1000));
    await tester.pump();
    expect(find.byType(CircularProgressIndicator), findsOneWidget);

    page2.complete(feedPage([textCard('p-3')]));
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -600));
    await tester.pump();

    // keyset 游标不丢不重：三帖各恰一张，游标原样带出。
    expect(repository.calls.where((c) => c.startsWith('feed:')).toList(), [
      'feed:cursor=null',
      'feed:cursor=c1',
    ]);
    expect(find.text('动态内容 p-1'), findsOneWidget);
    expect(find.text('动态内容 p-2'), findsOneWidget);
    expect(find.text('动态内容 p-3'), findsOneWidget);
    expect(find.text('没有更多了'), findsOneWidget);
  });

  testWidgets('尾部失败：重试条 + feed_load_failed(load_more)，点按重试补页', (tester) async {
    var page2Attempts = 0;
    repository.onFeed = (_, cursor) async {
      if (cursor == null) {
        return feedPage([textCard('p-1')], nextCursor: 'c1', hasMore: true);
      }
      page2Attempts += 1;
      if (page2Attempts == 1) {
        throw const ApiBusinessException(code: 40000, message: 'x');
      }
      return feedPage([textCard('p-2')]);
    };

    await pumpHome(tester);
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -1000));
    await tester.pumpAndSettle();

    expect(find.text('加载失败，点此重试'), findsOneWidget);
    expect(eventsNamed('feed_load_failed'), [
      {
        'feedTab': 'home',
        'loadType': 'load_more',
        'failureReason': 'server_error',
        'errorCode': 40000,
        'httpStatus': 400,
      },
    ]);

    await tester.tap(find.text('加载失败，点此重试'));
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -400));
    await tester.pump();
    expect(find.text('动态内容 p-2'), findsOneWidget);
    expect(find.text('加载失败，点此重试'), findsNothing);
  });

  testWidgets('下拉刷新：整体替换列表；刷新失败保留旧列表 + SnackBar', (tester) async {
    var attempts = 0;
    repository.onFeed = (_, _) async {
      attempts += 1;
      if (attempts == 1) return feedPage([textCard('p-1')]);
      if (attempts == 2) throw const ApiNetworkException();
      return feedPage([textCard('p-9')]);
    };

    await pumpHome(tester);
    await tester.pumpAndSettle();
    expect(find.text('动态内容 p-1'), findsOneWidget);

    // 第一次下拉：失败——旧列表保留、SnackBar 轻提示、事件上报。
    await tester.fling(list(), const Offset(0, 400), 1000);
    await tester.pumpAndSettle();
    expect(find.text('动态内容 p-1'), findsOneWidget);
    expect(find.text('网络异常，请检查网络后重试'), findsOneWidget);
    expect(eventsNamed('feed_load_failed').single?['loadType'], 'refresh');

    // 第二次下拉：成功——整体替换不残留旧卡。
    await tester.fling(list(), const Offset(0, 400), 1000);
    await tester.pumpAndSettle();
    expect(find.text('动态内容 p-9'), findsOneWidget);
    expect(find.text('动态内容 p-1'), findsNothing);
  });

  testWidgets('曝光结算 · 切走 Tab：可见 ≥500ms 的卡片计入，一段恰一条 feed_viewed', (
    tester,
  ) async {
    repository.onFeed = (_, _) async =>
        feedPage([textCard('p-1'), textCard('p-2')]);

    await pumpHome(tester);
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -1000));
    // 先渲染一帧（滚动后位置在帧末扫描），再驻留满 500ms（曝光判定），
    // 随后切走 Tab 结算。
    await tester.pump();
    await tester.pump(const Duration(milliseconds: 600));

    expect(eventsNamed('feed_viewed'), isEmpty);
    await pumpHome(tester, isActive: false);
    await tester.pump();

    final viewed = eventsNamed('feed_viewed');
    expect(viewed, hasLength(1));
    expect(viewed.single?['feedTab'], 'home');
    expect(viewed.single?['impressionCount'], 2);
    // 首屏自动预取不计刷新，本段无翻页。
    expect(viewed.single?['refreshCount'], 0);
    expect(viewed.single?['loadMoreCount'], 0);
    // durationMs 取真实时钟（生产语义），widget 测试的 pump 只推进假
    // 时钟，此处仅验证字段在场非负（精确口径见 feed_exposure_test）。
    expect(viewed.single?['durationMs'], greaterThanOrEqualTo(0));

    // 切回 Tab 开新段：再切走仍恰一条新事件（幂等不翻倍）。
    await pumpHome(tester);
    await tester.pump();
    await pumpHome(tester, isActive: false);
    await tester.pump();
    expect(eventsNamed('feed_viewed'), hasLength(2));
  });

  testWidgets('曝光结算 · 快速滑过不计；刷新/翻页计数入段', (tester) async {
    final cards = List.generate(6, (i) => textCard('p-$i'));
    repository.onFeed = (_, cursor) async {
      if (cursor == null) {
        return feedPage(cards, nextCursor: 'c1', hasMore: true);
      }
      return feedPage([textCard('p-6')]);
    };

    await pumpHome(tester);
    await tester.pumpAndSettle();

    // 快速滑到底（各卡驻留 <500ms）→ 触发一次翻页。
    await tester.drag(list(), const Offset(0, -2000));
    await tester.pumpAndSettle();
    // 用户下拉刷新一次。
    await tester.drag(list(), const Offset(0, 2000));
    await tester.pump();
    await tester.fling(list(), const Offset(0, 400), 1000);
    await tester.pumpAndSettle();

    await pumpHome(tester, isActive: false);
    await tester.pump();

    final viewed = eventsNamed('feed_viewed').single!;
    expect(viewed['refreshCount'], 1);
    expect(viewed['loadMoreCount'], 1);
    // 快速滑过的中段卡片未驻留满 500ms，不应全量计曝光。
    expect(viewed['impressionCount'], lessThan(cards.length));
  });

  testWidgets('曝光结算 · 退后台：结算一条，回前台开新段', (tester) async {
    repository.onFeed = (_, _) async => feedPage([textCard('p-1')]);

    await pumpHome(tester);
    await tester.pumpAndSettle();

    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.paused);
    await tester.pump();
    // 级联 inactive→hidden→paused 只结算一次。
    expect(eventsNamed('feed_viewed'), hasLength(1));

    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.resumed);
    await tester.pump();
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.paused);
    await tester.pump();
    expect(eventsNamed('feed_viewed'), hasLength(2));

    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.resumed);
    await tester.pump();
  });

  testWidgets('曝光结算 · 切到服务分段：结算；切回开新段', (tester) async {
    repository.onFeed = (_, _) async => feedPage([textCard('p-1')]);

    await pumpHome(tester);
    await tester.pumpAndSettle();

    await tester.tap(find.text('本地服务'));
    await tester.pump();
    expect(eventsNamed('feed_viewed'), hasLength(1));

    await tester.tap(find.text('社区动态'));
    await tester.pump();
    await tester.tap(find.text('本地服务'));
    await tester.pump();
    expect(eventsNamed('feed_viewed'), hasLength(2));
  });

  testWidgets('T3-15 导航接通：整卡与评论钮点按回调 onOpenPost（占位提示移除）', (tester) async {
    repository.onFeed = (_, _) async => feedPage([textCard('p-1')]);

    await pumpHome(tester);
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -600));
    await tester.pump();

    await tester.tap(find.text('动态内容 p-1'));
    await tester.pump();
    expect(find.text('帖子详情正在接入真实数据，敬请期待'), findsNothing);
    expect(openedPosts, ['p-1']);

    await tester.tap(find.byIcon(Icons.chat_bubble_outline));
    await tester.pump();
    expect(openedPosts, ['p-1', 'p-1']);
  });

  testWidgets('T3-16 互动接线：点赞乐观翻转即时显示，成功报 post_liked(source=feed)', (
    tester,
  ) async {
    repository.onFeed = (_, _) async => feedPage([
      FeedCard.fromJson({
        ...sampleFeedCardJson(likeCount: 6),
        'coverImage': null,
        'mediaCount': 0,
      }),
    ]);
    final like = Completer<LikeState>();
    repository.onLikeToggle = (_, _) => like.future;

    await pumpHome(tester);
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -800));
    await tester.pumpAndSettle();

    await tester.tap(find.byIcon(Icons.favorite_border));
    await tester.pump();
    // 乐观翻转：请求未回已 +1（同帧反馈）。
    expect(find.text('7'), findsOneWidget);
    expect(repository.calls, contains('like:p-1'));

    like.complete(const LikeState(liked: true, likeCount: 7));
    await tester.pumpAndSettle();
    expect(eventsNamed('post_liked'), [
      {'source': 'feed'},
    ]);
    expect(find.text('7'), findsOneWidget);
  });

  testWidgets('T3-16 互动接线：点赞失败回滚 + SnackBar「操作失败，请重试」', (tester) async {
    repository.onFeed = (_, _) async => feedPage([
      FeedCard.fromJson({
        ...sampleFeedCardJson(likeCount: 6),
        'coverImage': null,
        'mediaCount': 0,
      }),
    ]);
    final like = Completer<LikeState>();
    repository.onLikeToggle = (_, _) => like.future;

    await pumpHome(tester);
    await tester.pumpAndSettle();
    await tester.drag(list(), const Offset(0, -800));
    await tester.pumpAndSettle();

    await tester.tap(find.byIcon(Icons.favorite_border));
    await tester.pump();
    expect(find.text('7'), findsOneWidget);

    like.completeError(const ApiNetworkException());
    await tester.pumpAndSettle();
    // 回滚成对恢复 + SnackBar；不报 post_liked。
    expect(find.text('6'), findsOneWidget);
    expect(find.text('操作失败，请重试'), findsOneWidget);
    expect(eventsNamed('post_liked'), isEmpty);
  });

  testWidgets('搜索词过滤已加载卡片；无命中显搜索空态', (tester) async {
    repository.onFeed = (_, _) async =>
        feedPage([textCard('p-1'), textCard('p-2')]);

    await pumpHome(tester);
    await tester.pumpAndSettle();

    await tester.enterText(find.byType(TextField), 'p-1');
    await tester.pump();
    expect(find.byType(PostCard), findsOneWidget);

    await tester.enterText(find.byType(TextField), '不存在的词');
    await tester.pump();
    expect(find.byType(PostCard), findsNothing);
    expect(find.text('没有找到相关动态'), findsOneWidget);
  });
}