import 'package:flutter/material.dart';

import '../../core/ui/app_dialog.dart';
import 'package:flutter/services.dart';
import 'package:share_plus/share_plus.dart';

import '../../core/data/backend.dart' show BackendException;
import '../../core/i18n/app_locale.dart';
import '../../core/theme/tokens.dart';
import '../../core/ui/app_icons.dart';
import '../../core/ui/relative_time.dart';
import '../home/home_screen.dart' show formatPop;
import '../my/profile_edit_screen.dart';
import '../planet/moderation.dart';
import '../translation/translation_comments.dart';
import '../translation/translation_data.dart';
import 'campaign_data.dart';
import 'campaign_ranking_screen.dart';
import 'campaign_share.dart';
import 'widgets/campaign_gauge.dart';
import 'widgets/campaign_list_card.dart' show CampaignAuthor;
import 'widgets/campaign_rank.dart';
import 'widgets/campaign_share_dialog.dart';
import 'widgets/campaign_style.dart';
import '../../core/ui/fx_intensity.dart';

/// 캠페인 상세 — 화면 대조 원장 F5 · Figma `272:245738`.
///
/// 신고하기는 `272:246311` 이며 [ReportScreen] 을 공용으로 쓴다.
///
/// 명세 `523:18493` — *디폴트 첫 번째 사진 노출 · 사진/영상 개수에 따른 인디케이터 수*
/// 명세 `523:18525` — *상세 페이지 진입과 동시에 조회수 +1 · 좋아요 클릭 시 +1*
/// 명세 `523:18559` — *캠페인 정보 탭 · 응원 게시판 +댓글수 탭 · 디폴트 캠페인 정보*
/// 명세 `523:18569` — *기여율 · 누적 POP · 목표 · 참여 인원 · 남은 시간*
/// 명세 `523:18589` — *기여하기 버튼은 **타인 캠페인에서만** 표시*
class CampaignDetailScreen extends StatefulWidget {
  CampaignDetailScreen({
    super.key,
    required this.campaignId,
    CampaignRepository? repository,
    this.myPop,
    this.translation,
  }) : repository = repository ?? SampleCampaignRepository();

  final String campaignId;
  final CampaignRepository repository;

  /// 후원 가능 잔액. 넘기지 않으면 저장소에서 읽는다(기여 POP · B-33).
  final int? myPop;

  /// 참여형 번역 — 없으면 앱 루트의 [TranslationScope] 를 쓴다.
  final TranslationRepository? translation;

  @override
  State<CampaignDetailScreen> createState() => _CampaignDetailScreenState();
}

class _CampaignDetailScreenState extends State<CampaignDetailScreen> {
  final _media = PageController();

  CampaignDetail? _detail;
  int _page = 0;
  int _tabIndex = 0;
  int _likes = 0;
  bool _liked = false;
  int _raised = 0;
  int _spent = 0;
  int _balance = 0;
  Object? _error;

  /// 응원 게시판 댓글(최신순). null 이면 아직 읽는 중.
  List<CampaignComment>? _comments;
  bool _moreComments = false;
  int _commentCount = 0;

  /// 공개 닉네임이 있는가 — 없으면 입력 대신 닉네임 안내를 띄운다.
  bool _hasNickname = true;

  /// 번역할 댓글. 없으면 번역 댓글은 캠페인 본문의 번역이다(Q-TR-07 A안).
  TranslationReplyTarget? _replyTo;

  TranslationRepository? get _translation =>
      translationSurfaces.contains(TranslationSurface.campaignBoard)
      ? widget.translation ?? TranslationScope.maybeOf(context)
      : null;

  String get _root => 'campaigns/${widget.campaignId}';

  @override
  void initState() {
    super.initState();
    _load();
    _loadComments();
  }

  @override
  void dispose() {
    _media.dispose();
    super.dispose();
  }

  Future<void> _load() async {
    final CampaignDetail detail;
    final int balance;
    try {
      detail = await widget.repository.detail(widget.campaignId);
      balance = widget.myPop ?? await widget.repository.balance();
    } on Object catch (error) {
      if (mounted) setState(() => _error = error);
      return;
    }
    if (!mounted) return;
    setState(() {
      _balance = balance;
      _detail = detail;
      _likes = detail.card.likes;
      _liked = detail.liked;
      _raised = detail.card.raisedPop;
      _commentCount = detail.card.comments;
    });
  }

  Future<void> _loadComments({bool more = false}) async {
    final List<CampaignComment> page;
    try {
      if (!more) _hasNickname = await widget.repository.hasPublicNickname();
      page = await widget.repository.comments(widget.campaignId, more: more);
    } on Object catch (error) {
      if (!mounted) return;
      setState(() => _comments ??= const []);
      _fail(error);
      return;
    }
    if (!mounted) return;
    setState(() {
      _comments = [if (more) ...?_comments, ...page];
      _moreComments = page.length >= campaignCommentPageSize;
    });
  }

  Future<bool> _send(String body) async {
    try {
      final c = await widget.repository.addComment(widget.campaignId, body);
      if (!mounted) return true;
      setState(() {
        _comments = [c, ...?_comments];
        _commentCount++;
      });
      return true;
    } on Object catch (error) {
      _fail(error);
      return false;
    }
  }

  /// 댓글 좋아요 — 저장이 끝난 뒤에만 숫자를 바꾼다(캠페인 좋아요와 같은 방식).
  Future<void> _likeComment(CampaignComment c) async {
    final on = !c.liked;
    try {
      await widget.repository.likeComment(widget.campaignId, c.id, on);
    } on Object catch (error) {
      _fail(error);
      return;
    }
    if (!mounted) return;
    final next = CampaignComment(
      id: c.id,
      authorName: c.authorName,
      body: c.body,
      createdAt: c.createdAt,
      authorUid: c.authorUid,
      isMine: c.isMine,
      liked: on,
      likes: c.likes + (on ? 1 : -1),
    );
    setState(
      () => _comments = [
        for (final x in _comments ?? const <CampaignComment>[])
          x == c ? next : x,
      ],
    );
  }

  /// 댓글 카드의 더보기 — 내 댓글은 삭제, 남의 댓글은 신고 · 차단(명세 `527:21192`).
  Future<void> _commentAction(CampaignComment c, String action) async {
    final repo = widget.repository;
    try {
      switch (action) {
        case 'delete':
          if (!await confirmOverlay(
            context,
            context.l10n.commentDeleteConfirm,
          )) {
            return;
          }
          await repo.deleteComment(widget.campaignId, c.id);
          if (!mounted) return;
          setState(() {
            _comments = [...?_comments]..remove(c);
            if (_commentCount > 0) _commentCount--;
          });
        case 'report':
          final reason = await Navigator.of(context, rootNavigator: true)
              .push<String>(
                MaterialPageRoute(
                  builder: (_) => ReportScreen(
                    target: ModerationTarget(
                      authorName: c.authorName,
                      title: c.body,
                    ),
                  ),
                ),
              );
          if (reason == null) return;
          await repo.reportComment(widget.campaignId, c, reason);
          if (mounted) _toast(context.l10n.reportReceived);
        case 'block':
          if (!await confirmBlock(context, c.authorName)) return;
          await repo.blockAuthor(c);
          if (!mounted) return;
          // 차단한 작성자의 댓글은 바로 숨긴다 — 다음 읽기부터는 저장소가 뺀다.
          setState(
            () => _comments = [
              for (final x in _comments ?? const <CampaignComment>[])
                if (x.authorUid != c.authorUid) x,
            ],
          );
          _toast(context.l10n.blocked);
      }
    } on Object catch (error) {
      _fail(error);
    }
  }

  @override
  Widget build(BuildContext context) {
    final detail = _detail;
    if (detail == null) {
      final error = _error;
      return Scaffold(
        appBar: error == null ? null : AppBar(),
        body: Center(
          child: error == null
              ? const CircularProgressIndicator()
              : Text(
                  error is BackendException
                      ? error.message
                      : context.l10n.campaignLoadFailed,
                ),
        ),
      );
    }
    final card = detail.card;

    // 시안(272:245738) — 대표 이미지 360 위에 반투명 원형 버튼 둘(42 · #000 60%)이 뜨고,
    // 제목 · 본문 · 탭 · 펀딩 현황이 한 스크롤에 이어진다. 탭은 고정 헤더가 아니다.
    return Scaffold(
      extendBodyBehindAppBar: true,
      appBar: AppBar(
        backgroundColor: Colors.transparent,
        toolbarHeight: 54,
        leadingWidth: 58,
        leading: const Padding(
          padding: EdgeInsets.only(left: 16),
          child: _Round(child: BackButton()),
        ),
        actions: [
          Padding(
            padding: const EdgeInsets.only(right: 16),
            child: _Round(
              child: PopupMenuButton<String>(
                tooltip: context.l10n.commonMore,
                icon: const ImageIcon(AppIcons.ellipsisVertical, size: 24),
                onSelected: (v) => _moderate(v, card),
                itemBuilder: (_) => [
                  PopupMenuItem(
                    value: 'report',
                    child: Text(context.l10n.reportTitle),
                  ),
                  PopupMenuItem(
                    value: 'block',
                    child: Text(context.l10n.commonBlockAction),
                  ),
                ],
              ),
            ),
          ),
        ],
      ),
      body: ListView(
        key: const ValueKey('campaign-info'),
        padding: EdgeInsets.only(bottom: card.mine ? AppSpace.s5 : 96),
        children: [
          _hero(detail),
          Padding(
            padding: const EdgeInsets.fromLTRB(20, 12, 20, 12),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Row(
                  children: [
                    Expanded(
                      child: CampaignAuthor(
                        name: card.authorName,
                        createdAt: card.createdAt,
                      ),
                    ),
                    Tooltip(
                      message: context.l10n.commonShare,
                      child: Material(
                        color: AppColors.cosmicSurfaceContainer,
                        shape: const StadiumBorder(),
                        child: InkWell(
                          onTap: () => _share(card),
                          customBorder: const StadiumBorder(),
                          child: Padding(
                            padding: const EdgeInsets.symmetric(
                              horizontal: 8,
                              vertical: 6,
                            ),
                            child: Row(
                              mainAxisSize: MainAxisSize.min,
                              children: [
                                Text(
                                  context.l10n.commonShare,
                                  style: campaignText(
                                    12,
                                    600,
                                    AppColors.onCosmicVariant,
                                    height: 1,
                                    spacing: 0,
                                  ),
                                ),
                                const SizedBox(width: 4),
                                const ImageIcon(
                                  AppIcons.share,
                                  size: 14,
                                  color: AppColors.onCosmicVariant,
                                ),
                              ],
                            ),
                          ),
                        ),
                      ),
                    ),
                  ],
                ),
                const SizedBox(height: 12),
                Text(
                  card.title,
                  style: campaignText(24, 500, AppColors.onCosmic, height: 1.4),
                ),
                const SizedBox(height: 12),
                Text(
                  card.body,
                  style: campaignText(
                    14,
                    500,
                    const Color(0xFFC2C2C2),
                    height: 1.4,
                  ),
                ),
                const SizedBox(height: 12),
                Row(
                  children: [
                    InkResponse(
                      onTap: _like,
                      radius: 16,
                      child: Tooltip(
                        message: context.l10n.like,
                        child: Icon(
                          _liked ? Icons.favorite : Icons.favorite_border,
                          size: 16,
                          color: _liked
                              ? AppColors.cosmicAccent
                              : AppColors.onCosmic,
                        ),
                      ),
                    ),
                    const SizedBox(width: 4),
                    Text(formatReaction(_likes), style: _reaction),
                    const SizedBox(width: 12),
                    const Icon(
                      Icons.visibility_outlined,
                      size: 16,
                      color: AppColors.onCosmic,
                    ),
                    const SizedBox(width: 4),
                    // 진입과 동시에 +1.
                    Text(formatReaction(card.views + 1), style: _reaction),
                    const SizedBox(width: 12),
                    const Icon(
                      Icons.share_outlined,
                      size: 16,
                      color: AppColors.onCosmic,
                    ),
                    const SizedBox(width: 4),
                    Text(formatReaction(card.shares), style: _reaction),
                  ],
                ),
              ],
            ),
          ),
          Padding(
            padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 10),
            child: Row(
              children: [
                _tab(context.l10n.campaignTabInfo, 0),
                _tab(context.l10n.campaignTabBoard('$_commentCount'), 1),
              ],
            ),
          ),
          if (_tabIndex == 0) _info(detail) else _board(),
        ],
      ),
      // 명세 — 기여하기는 타인 캠페인에서만. 내 캠페인은 철회할 수 있을 때 철회 버튼(B-58).
      // 응원 게시판 탭은 하단에 댓글 입력 영역을 고정한다(명세 `527:21196`).
      // 기본은 일반 댓글, 지구본을 켜면 캠페인 본문의 번역 댓글이다.
      bottomNavigationBar: _tabIndex == 1 && !_hasNickname
          ? _nicknamePrompt()
          : _tabIndex == 1
          ? CommentInputBar(
              hint: context.l10n.commentHint,
              onComment: _send,
              // 규칙의 댓글 상한과 같은 수.
              maxLength: 1000,
              translation: _translation,
              rootPath: _root,
              replyTo: _replyTo,
              onClearReply: () => setState(() => _replyTo = null),
            )
          : card.mine
          ? (_withdrawable(card)
                ? SafeArea(
                    child: Padding(
                      padding: const EdgeInsets.fromLTRB(20, 8, 20, 8),
                      child: OutlinedButton(
                        onPressed: () => _withdraw(card),
                        style: OutlinedButton.styleFrom(
                          minimumSize: const Size.fromHeight(50),
                          foregroundColor: AppColors.onCosmic,
                          shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(AppRadius.sm),
                          ),
                        ),
                        child: Text(context.l10n.campaignWithdraw),
                      ),
                    ),
                  )
                : null)
          : SafeArea(
              child: Padding(
                padding: const EdgeInsets.fromLTRB(20, 8, 20, 8),
                child: FilledButton(
                  onPressed: () => _contribute(detail),
                  style: FilledButton.styleFrom(
                    minimumSize: const Size.fromHeight(50),
                    backgroundColor: AppColors.onCosmic,
                    foregroundColor: Colors.black,
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(AppRadius.sm),
                    ),
                    textStyle: campaignText(14, 600, Colors.black, height: 1.3),
                  ),
                  child: Text(context.l10n.campaignContributeAction),
                ),
              ),
            ),
    );
  }

  /// 닉네임 없는 사용자 — 응원 게시판 댓글은 「팬」으로 쓸 수 없다(규칙과 같은 조건).
  Widget _nicknamePrompt() => ColoredBox(
    color: AppColors.cosmicVoid,
    child: SafeArea(
      top: false,
      child: Padding(
        padding: const EdgeInsets.fromLTRB(16, 10, 10, 10),
        child: Row(
          children: [
            Expanded(
              child: Text(
                context.l10n.campaignCommentNeedNickname,
                style: campaignText(14, 500, AppColors.onCosmicMuted),
              ),
            ),
            TextButton(
              onPressed: () async {
                await Navigator.of(context, rootNavigator: true).push(
                  MaterialPageRoute<void>(
                    builder: (_) => ProfileEditScreen(
                      nickname: '',
                      repository: widget.repository.my,
                    ),
                  ),
                );
                final ok = await widget.repository.hasPublicNickname();
                if (mounted) setState(() => _hasNickname = ok);
              },
              child: Text(context.l10n.campaignCommentSetNickname),
            ),
          ],
        ),
      ),
    ),
  );

  static final _reaction = campaignText(12, 500, AppColors.onCosmic, height: 1);

  /// 대표 이미지 — 상태 표시줄을 포함해 360. 인디케이터 수는 사진 개수를 따른다.
  Widget _hero(CampaignDetail detail) => SizedBox(
    height: 312 + MediaQuery.paddingOf(context).top,
    child: Stack(
      fit: StackFit.expand,
      children: [
        PageView(
          // 사진 슬라이드를 가려내는 표식.
          key: const ValueKey('campaign-media'),
          controller: _media,
          onPageChanged: (i) => setState(() => _page = i),
          children: [
            // 캠페인 문서의 사진은 아직 라벨뿐이라 시안 표본을 깐다.
            for (final label in detail.mediaLabels)
              Image.asset(
                'assets/figma/campaign-sample.png',
                fit: BoxFit.cover,
                semanticLabel: label,
              ),
          ],
        ),
        if (detail.mediaLabels.length > 1)
          Positioned(
            bottom: 12,
            left: 0,
            right: 0,
            child: Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                for (var i = 0; i < detail.mediaLabels.length; i++)
                  Container(
                    width: i == _page ? 16 : 6,
                    height: 6,
                    margin: const EdgeInsets.symmetric(horizontal: 2),
                    decoration: BoxDecoration(
                      borderRadius: BorderRadius.circular(AppRadius.full),
                      color: i == _page
                          ? AppColors.onCosmic
                          : AppColors.onCosmic.withValues(alpha: 0.5),
                    ),
                  ),
              ],
            ),
          ),
      ],
    ),
  );

  /// 탭 — 반폭 · 글자 14/500 · 선택 흰 글자·흰 밑줄, 비선택 #84868e · #1b1c1c 밑줄.
  Widget _tab(String label, int index) {
    final on = _tabIndex == index;
    return Expanded(
      child: InkWell(
        onTap: () => setState(() => _tabIndex = index),
        child: Container(
          height: 37,
          alignment: Alignment.center,
          decoration: BoxDecoration(
            border: Border(
              bottom: BorderSide(
                color: on ? AppColors.onCosmic : const Color(0xFF1B1C1C),
              ),
            ),
          ),
          child: Text(
            label,
            style: campaignText(
              14,
              500,
              on ? AppColors.onCosmic : const Color(0xFF84868E),
              spacing: 0,
            ),
          ),
        ),
      ),
    );
  }

  Widget _info(CampaignDetail detail) {
    final card = detail.card;
    final sorted = [...detail.topContributors]
      ..sort((a, b) => a.rank.compareTo(b.rank));
    return Padding(
      padding: const EdgeInsets.fromLTRB(20, 12, 20, 12),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          if (card.status.notice case final notice?) ...[
            Container(
              key: const ValueKey('campaign-status-notice'),
              padding: const EdgeInsets.all(12),
              decoration: BoxDecoration(
                color: AppColors.cosmicSurfaceContainer,
                borderRadius: BorderRadius.circular(AppRadius.sm),
              ),
              child: Text(
                notice,
                style: campaignText(14, 500, AppColors.onCosmic, height: 1.4),
              ),
            ),
            const SizedBox(height: 12),
          ],
          Text(
            context.l10n.campaignFundingStatus,
            style: campaignText(18, 600, AppColors.onCosmic, spacing: 0),
          ),
          const SizedBox(height: 12),
          CampaignGauge(raised: _raised, goal: card.goalPop),
          const SizedBox(height: 6),
          Row(
            children: [
              _stat(
                // 서버 donorCount(고유 후원자 수)를 그대로 쓴다. 후원 뒤 상세를 다시 읽으므로 화면이 더하지 않는다.
                formatPop(card.supporters),
                context.l10n.campaignSupporting,
              ),
              const SizedBox(width: 6),
              _stat(_left(detail.remaining()), context.l10n.campaignTimeLeft),
            ],
          ),
          const SizedBox(height: AppSpace.s5),
          CampaignRankHeader(
            window: RankWindow.live,
            onTap: () => _openRanking(detail),
          ),
          const SizedBox(height: 12),
          RankPodium(top: sorted.take(3).toList()),
          for (final r in sorted.skip(3)) RankRow(rank: r),
          if (detail.report case final report?) ...[
            const SizedBox(height: AppSpace.s5),
            _reportSection(report),
          ],
        ],
      ),
    );
  }

  /// 결과보고 — 집행 사진 · 영수증 · 예산 사용 내역(FR-CMP-06). 운영이 올린다(B-35).
  Widget _reportSection(CampaignReport report) {
    final heading = campaignText(18, 600, AppColors.onCosmic, spacing: 0);
    final sub = campaignText(14, 600, AppColors.onCosmic, spacing: 0);
    final text = campaignText(14, 500, AppColors.onCosmic, height: 1.4);
    Widget photos(List<String> urls, String label) => Column(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        for (final url in urls)
          Padding(
            padding: const EdgeInsets.only(bottom: AppSpace.s2),
            child: ClipRRect(
              borderRadius: BorderRadius.circular(AppRadius.sm),
              child: Image.network(
                url,
                fit: BoxFit.cover,
                semanticLabel: label,
                errorBuilder: (_, _, _) => const SizedBox(
                  height: 120,
                  child: Center(child: Icon(Icons.broken_image_outlined)),
                ),
              ),
            ),
          ),
      ],
    );
    return Column(
      key: const ValueKey('campaign-report'),
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        Text(context.l10n.campaignReport, style: heading),
        const SizedBox(height: 4),
        Text(
          relativeTime(report.createdAt),
          style: campaignText(12, 500, AppColors.onCosmicMuted),
        ),
        const SizedBox(height: 12),
        photos(report.photoUrls, context.l10n.campaignReportPhotos),
        Text(report.body, style: text),
        const SizedBox(height: AppSpace.s5),
        Text(context.l10n.campaignBudget, style: sub),
        const SizedBox(height: AppSpace.s2),
        for (final line in report.budget)
          Padding(
            padding: const EdgeInsets.only(bottom: 4),
            child: Row(
              children: [
                Expanded(child: Text(line.label, style: text)),
                Text('${formatPop(line.amount)} POP', style: text),
              ],
            ),
          ),
        const Divider(),
        Row(
          children: [
            Expanded(child: Text(context.l10n.campaignTotal, style: sub)),
            Text('${formatPop(report.budgetTotal)} POP', style: sub),
          ],
        ),
        const SizedBox(height: AppSpace.s5),
        Text(context.l10n.campaignReceipts, style: sub),
        const SizedBox(height: AppSpace.s2),
        photos(report.receiptUrls, context.l10n.campaignReceipts),
      ],
    );
  }

  /// 응원 중 · 남은 시간 칸 — #1a1a1c r8 높이 80, 값 20/500 · 라벨 12/500.
  Widget _stat(String value, String label) => Expanded(
    child: Container(
      height: 80,
      decoration: BoxDecoration(
        color: AppColors.cosmicSurfaceContainer,
        borderRadius: BorderRadius.circular(AppRadius.sm),
      ),
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Text(
            value,
            style: campaignText(
              20,
              500,
              AppColors.onCosmic,
              height: 1.2,
              spacing: 0,
            ),
          ),
          const SizedBox(height: 4),
          Text(
            label,
            style: campaignText(12, 500, AppColors.onCosmic, spacing: 0),
          ),
        ],
      ),
    ),
  );

  /// 시안 「6일 23:59:06」 — 일 · 시:분:초.
  String _left(Duration d) {
    String two(int v) => v.toString().padLeft(2, '0');
    final hms =
        '${two(d.inHours % 24)}:${two(d.inMinutes % 60)}:${two(d.inSeconds % 60)}';
    return d.inDays > 0
        ? context.l10n.campaignDaysLeft('${d.inDays}', hms)
        : hms;
  }

  Widget _board() => Padding(
    padding: const EdgeInsets.all(20),
    child: switch (_translation) {
      final t? => TranslationThreads(
        repository: t,
        rootPath: _root,
        builder: (_, byTarget) => _boardBody(t, byTarget),
      ),
      null => _boardBody(null, const {}),
    },
  );

  /// 댓글(최신순) → 더 보기 → 캠페인 본문의 번역 댓글(시안 `527:21198`).
  /// 댓글마다 그 댓글의 번역 댓글을 대댓글 자리에 붙인다(라운지와 같은 배치).
  Widget _boardBody(
    TranslationRepository? t,
    Map<String, List<TranslationEntry>> byTarget,
  ) {
    final own = byTarget[_root] ?? const <TranslationEntry>[];
    final comments = _comments;
    if (comments == null) {
      return const Center(child: CircularProgressIndicator());
    }
    return Column(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        if (comments.isEmpty && own.isEmpty)
          Text(
            context.l10n.commentFirst,
            textAlign: TextAlign.center,
            style: campaignText(12, 500, AppColors.onCosmicMuted),
          ),
        for (final (i, c) in comments.indexed) ...[
          if (i > 0) const Divider(height: AppSpace.s5),
          _commentCard(c, t),
          for (final e in byTarget['$_root/comments/${c.id}'] ?? const [])
            Padding(
              padding: const EdgeInsets.only(top: AppSpace.s3),
              child: TranslationCommentCard(
                entry: e,
                repository: t!,
                reply: true,
              ),
            ),
        ],
        if (_moreComments)
          TextButton(
            onPressed: () => _loadComments(more: true),
            child: Text(context.l10n.commonMore),
          ),
        for (final e in own)
          Padding(
            padding: const EdgeInsets.only(top: AppSpace.s4),
            child: TranslationCommentCard(entry: e, repository: t!),
          ),
      ],
    );
  }

  /// 댓글 카드 — 명세 `527:21192` *좋아요 · 대댓글(번역) · 신고/차단*.
  Widget _commentCard(CampaignComment c, TranslationRepository? t) => Row(
    crossAxisAlignment: CrossAxisAlignment.start,
    children: [
      Expanded(
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Flexible(
                  child: Text(
                    c.authorName,
                    overflow: TextOverflow.ellipsis,
                    style: campaignText(12, 500, AppColors.onCosmic),
                  ),
                ),
                const SizedBox(width: AppSpace.s2),
                Text(
                  relativeTime(c.createdAt),
                  style: campaignText(10, 500, AppColors.onCosmicMuted),
                ),
              ],
            ),
            const SizedBox(height: 4),
            Text(
              c.body,
              style: campaignText(14, 500, AppColors.onCosmic, height: 1.4),
            ),
            const SizedBox(height: 6),
            Row(
              children: [
                InkWell(
                  onTap: () => _likeComment(c),
                  child: Tooltip(
                    message: context.l10n.like,
                    child: Icon(
                      c.liked ? Icons.favorite : Icons.favorite_border,
                      size: 14,
                      color: c.liked
                          ? AppColors.cosmicAccent
                          : AppColors.onCosmicMuted,
                    ),
                  ),
                ),
                const SizedBox(width: 4),
                Text(
                  formatReaction(c.likes),
                  style: campaignText(10, 500, AppColors.onCosmicMuted),
                ),
              ],
            ),
          ],
        ),
      ),
      if (t != null)
        IconButton(
          tooltip: context.l10n.translationWrite,
          visualDensity: VisualDensity.compact,
          onPressed: () => setState(
            () => _replyTo = (
              path: '$_root/comments/${c.id}',
              name: c.authorName,
            ),
          ),
          icon: const ImageIcon(
            AppIcons.globe,
            size: 16,
            color: AppColors.onCosmicMuted,
          ),
        ),
      PopupMenuButton<String>(
        tooltip: context.l10n.commonMore,
        padding: EdgeInsets.zero,
        icon: const ImageIcon(
          AppIcons.ellipsisVertical,
          size: 16,
          color: AppColors.onCosmicMuted,
        ),
        onSelected: (v) => _commentAction(c, v),
        itemBuilder: (_) => c.isMine
            ? [
                PopupMenuItem(
                  value: 'delete',
                  child: Text(context.l10n.commonDeleteAction),
                ),
              ]
            : [
                PopupMenuItem(
                  value: 'report',
                  child: Text(context.l10n.reportTitle),
                ),
                PopupMenuItem(
                  value: 'block',
                  child: Text(context.l10n.commonBlockAction),
                ),
              ],
      ),
    ],
  );

  /// 두 번 누르면 취소된다. 명세는 +1 만 적었으나 취소가 없으면 오조작을
  /// 되돌릴 수 없다. **저장이 끝난 뒤에만** 숫자를 바꾼다.
  Future<void> _like() async {
    final on = !_liked;
    try {
      await widget.repository.like(widget.campaignId, on);
    } on Object catch (error) {
      _fail(error);
      return;
    }
    if (!mounted) return;
    setState(() {
      _liked = on;
      _likes += on ? 1 : -1;
    });
  }

  /// B-58 — 공개 전(검수 중)이거나 공개 후 첫 후원 전이면 개설자가 철회할 수 있다.
  bool _withdrawable(CampaignCardData card) =>
      card.status == CampaignStatus.review ||
      (card.status == CampaignStatus.funding &&
          card.supporters == 0 &&
          _raised == 0);

  /// 철회 확인 — 등록비 반환 여부를 먼저 알린다(B-58 · 공개 전만 반환).
  Future<void> _withdraw(CampaignCardData card) async {
    final beforePublish = card.status == CampaignStatus.review;
    final go = await showConfirmDialog(
      context,
      context.l10n.campaignWithdrawTitle,
      confirmLabel: context.l10n.campaignWithdrawConfirm,
      body: beforePublish
              ? context.l10n.campaignWithdrawRefund(
                  formatPop(campaignRegistrationFeePop),
                )
              : context.l10n.campaignWithdrawNoRefund(
                  formatPop(campaignRegistrationFeePop),
                ),
    );
    if (!go || !mounted) return;
    try {
      await widget.repository.withdraw(card.id);
    } on Object catch (error) {
      _fail(error);
      return;
    }
    await _load();
  }

  void _fail(Object error) {
    if (!mounted) return;
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(
          error is BackendException
              ? error.message
              : context.l10n.commonRequestFailed,
        ),
      ),
    );
  }

  /// 기여하기 바텀시트 — 명세 `527:21100`.
  ///
  /// *기여 POP 설정 영역 - 디폴트 0, **보유 POP 이상 설정 불가** ·*
  /// *완료 버튼 - 디폴트 비활성화, 기여 POP 설정 후 활성화*
  Future<void> _contribute(CampaignDetail detail) async {
    final available = _balance - _spent;
    final amount = await showModalBottomSheet<int>(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      barrierColor: Colors.black.withValues(alpha: 0.7),
      builder: (context) => _ContributeSheet(available: available),
    );
    if (amount == null || amount <= 0 || !mounted) return;

    // **앱이 잔액을 깎지 않는다.** 원장은 fn-campaign-fund 가 쓴다.
    // 실패하면 숫자를 올리지 않고 사유를 알린다 — 성공처럼 그리지 않는다.
    final int applied;
    try {
      applied = await widget.repository.contribute(detail.card.id, amount);
    } on Object catch (error) {
      _fail(error);
      return;
    }
    if (!mounted) return;
    final before = _raised;
    setState(() {
      _spent += applied;
      _raised += applied;
    });
    // 실시간 랭킹(상위 3) · 모금액을 서버 값으로 다시 읽는다. 잔액 계산(_balance · _spent)은 그대로 둔다.
    try {
      final fresh = await widget.repository.detail(widget.campaignId);
      if (mounted) {
        setState(() {
          _detail = fresh;
          _raised = fresh.card.raisedPop;
        });
        // v1.5 §1 Legendary 「Campaign 100%」 — 서버가 다시 준 모금액으로 이번 후원이 목표를 넘긴 때만 1회.
        if (campaignJustCompleted(before, fresh.card.raisedPop, fresh.card.goalPop)) fxHaptic(FxIntensity.legendary);
      }
    } on Object catch (_) {
      // 다시 읽기 실패는 후원 결과와 무관하다 — 앞 화면을 그대로 둔다.
    }
  }

  Future<void> _openRanking(CampaignDetail detail) =>
      Navigator.of(context, rootNavigator: true).push(
        MaterialPageRoute<void>(
          builder: (_) => CampaignRankingScreen(
            campaignId: detail.card.id,
            repository: widget.repository,
          ),
        ),
      );

  /// 공유 오버레이 — Figma `480:14594`.
  ///
  /// 인스타그램 · 틱톡 · X 는 OS 공유 시트를 띄운다. 앱이 대상별 SDK 를 따로 넣지 않아도
  /// 사용자가 설치한 앱 가운데서 고르며, 시안의 버튼 넷은 그대로 남는다. 마지막 「링크
  /// 복사」는 **문구 전문을 클립보드에 담는다** — 웹 브릿지 주소가 설정되면 문구 안에
  /// `/c/<캠페인>` 링크가 들어간다([campaignShareLink]).
  ///
  /// 명세 — *공유 성공 콜백을 받을 경우 +1*. 지금은 세지 않는다. 공유 수를 올리는
  /// 것은 `campaigns` 문서의 집계 필드를 건드리는 일이고 규칙이 클라이언트 쓰기를
  /// 막아 두었다. 카운터는 캠페인 서버 연결 회차에서 Functions 로 붙는다.
  Future<void> _share(CampaignCardData card) async {
    final target = await CampaignShareDialog.show(
      context,
      card: card,
      raised: _raised,
    );
    switch (target) {
      case null:
        return;
      case CampaignShareTarget.link:
        await _copyText(card);
      default:
        await _shareText(card);
    }
  }

  String _shareBody(CampaignCardData card) => campaignShareText(
    title: card.title,
    summary: card.summary.isEmpty ? card.body : card.summary,
    fandomName: card.fandomName,
    link: campaignShareLink(card.id),
  );

  Future<void> _shareText(CampaignCardData card) async {
    await SharePlus.instance.share(
      ShareParams(text: _shareBody(card), subject: card.title),
    );
  }

  Future<void> _copyText(CampaignCardData card) async {
    await Clipboard.setData(ClipboardData(text: _shareBody(card)));
    if (mounted) _toast(context.l10n.shareCopied);
  }

  /// 캠페인 신고(`reports/campaign-{캠페인}-{신고자}`) · 개설자 차단.
  /// 차단하면 그 개설자의 캠페인 · 댓글이 빠지므로 상세를 닫는다.
  Future<void> _moderate(String action, CampaignCardData card) async {
    try {
      if (action == 'report') {
        final reason = await Navigator.of(context, rootNavigator: true)
            .push<String>(
              MaterialPageRoute(
                builder: (_) => ReportScreen(
                  target: ModerationTarget(
                    authorName: card.authorName,
                    title: card.title,
                  ),
                ),
              ),
            );
        if (reason == null) return;
        await widget.repository.reportCampaign(card.id, reason);
        if (mounted) _toast(context.l10n.reportReceived);
        return;
      }
      if (!await confirmBlock(context, card.authorName)) return;
      await widget.repository.blockCreator(card);
      if (!mounted) return;
      _toast(context.l10n.blocked);
      Navigator.pop(context);
    } on Object catch (error) {
      _fail(error);
    }
  }

  void _toast(String message) {
    ScaffoldMessenger.of(context)
      ..hideCurrentSnackBar()
      ..showSnackBar(
        SnackBar(content: Text(message), behavior: SnackBarBehavior.floating),
      );
  }
}

/// 기여 POP 설정 — 명세 `527:21100`.
class _ContributeSheet extends StatefulWidget {
  const _ContributeSheet({required this.available});

  final int available;

  @override
  State<_ContributeSheet> createState() => _ContributeSheetState();
}

class _ContributeSheetState extends State<_ContributeSheet> {
  double _amount = 0;

  // 시안 527:21100 — #1a1a1c r12 카드(안쪽 20 · 간격 14) + 8 + 완료 56(비활성 #333 · #777).
  @override
  Widget build(BuildContext context) {
    final max = widget.available.toDouble();
    final axis = campaignText(
      12,
      400,
      const Color(0xFFCDCDCD),
      height: 1,
      spacing: 0,
      family: AppFonts.display,
    );
    final ready = _amount >= 1;
    return SafeArea(
      child: Padding(
        padding: const EdgeInsets.fromLTRB(20, 0, 20, 8),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Container(
              padding: const EdgeInsets.all(20),
              decoration: BoxDecoration(
                color: AppColors.cosmicSurfaceContainer,
                borderRadius: BorderRadius.circular(AppRadius.md),
              ),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
                  Text(
                    context.l10n.campaignContributeAction,
                    textAlign: TextAlign.center,
                    style: campaignText(
                      18,
                      500,
                      AppColors.onCosmic,
                      height: 1.4,
                      spacing: 0,
                    ),
                  ),
                  const SizedBox(height: 14),
                  Text(
                    context.l10n.campaignContributePop,
                    style: campaignText(
                      14,
                      600,
                      AppColors.onCosmic,
                      spacing: 0,
                    ),
                  ),
                  const SizedBox(height: 14),
                  Container(
                    height: 77,
                    alignment: Alignment.center,
                    decoration: BoxDecoration(
                      color: AppColors.cosmicVoid,
                      borderRadius: BorderRadius.circular(AppRadius.sm),
                    ),
                    child: Text(
                      formatPop(_amount.round()),
                      style: campaignText(
                        32,
                        400,
                        AppColors.onCosmic,
                        height: 1.4,
                        family: AppFonts.display,
                      ),
                    ),
                  ),
                  const SizedBox(height: 18),
                  SliderTheme(
                    data: SliderThemeData(
                      trackHeight: 6,
                      padding: EdgeInsets.zero,
                      activeTrackColor: AppColors.cosmicTeal,
                      inactiveTrackColor: const Color(0xFF424242),
                      thumbColor: const Color(0xFF52A0C4),
                      overlayShape: SliderComponentShape.noOverlay,
                      thumbShape: const RoundSliderThumbShape(
                        enabledThumbRadius: 10,
                      ),
                    ),
                    child: SizedBox(
                      height: 20,
                      child: Slider(
                        value: _amount.clamp(0, max),
                        // 보유 POP 이상은 아예 끌 수 없다.
                        max: max <= 0 ? 1 : max,
                        onChanged: max <= 0
                            ? null
                            : (v) =>
                                  setState(() => _amount = v.roundToDouble()),
                      ),
                    ),
                  ),
                  const SizedBox(height: 6),
                  Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text('0', style: axis),
                      Text(formatPop(widget.available), style: axis),
                    ],
                  ),
                  const SizedBox(height: 18),
                  Padding(
                    padding: const EdgeInsets.symmetric(horizontal: 2),
                    child: Text.rich(
                      TextSpan(
                        text: context.l10n.commonMyPop,
                        children: [
                          TextSpan(
                            text: formatPop(widget.available),
                            style: const TextStyle(color: AppColors.onCosmic),
                          ),
                        ],
                      ),
                      style: campaignText(
                        14,
                        500,
                        AppColors.onCosmicVariant,
                        height: 1,
                      ),
                    ),
                  ),
                ],
              ),
            ),
            const SizedBox(height: 8),
            FilledButton(
              // 디폴트 비활성화 · 설정 후 활성화.
              onPressed: ready
                  ? () => Navigator.of(context).pop(_amount.round())
                  : null,
              style: FilledButton.styleFrom(
                minimumSize: const Size.fromHeight(56),
                backgroundColor: AppColors.onCosmic,
                foregroundColor: Colors.black,
                disabledBackgroundColor: const Color(0xFF333333),
                disabledForegroundColor: const Color(0xFF777777),
                shape: RoundedRectangleBorder(
                  borderRadius: BorderRadius.circular(AppRadius.sm),
                ),
                textStyle: campaignText(
                  16,
                  600,
                  Colors.black,
                  height: 1.5,
                  spacing: 0,
                ),
              ),
              child: Text(context.l10n.commonDone),
            ),
          ],
        ),
      ),
    );
  }
}

/// 대표 이미지 위 원형 버튼 — 42 · #000 60%.
class _Round extends StatelessWidget {
  const _Round({required this.child});

  final Widget child;

  @override
  Widget build(BuildContext context) => Center(
    child: Container(
      width: 42,
      height: 42,
      decoration: BoxDecoration(
        color: Colors.black.withValues(alpha: 0.6),
        shape: BoxShape.circle,
      ),
      child: Center(child: child),
    ),
  );
}

/// 이번 후원 전 모금액 [before] 가 목표 [goal] 미만이었고 서버 확정 모금액 [raised] 가 목표에 닿았는가.
bool campaignJustCompleted(int before, int raised, int goal) =>
    goal > 0 && before < goal && raised >= goal;