import 'dart:convert';
import 'dart:math';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:intl/intl.dart';

import '../../../../l10n/app_localizations.dart';
import '../../../../shared/theme/app_color_palette.dart';
import '../../../../shared/theme/design_tokens.dart';
import '../../../../shared/widgets/divination/divination_terms.dart';
import '../../../../shared/widgets/divination/yao_glyph.dart';
import '../../../../shared/widgets/divination/yao_legend.dart';
import '../../../../shared/widgets/toast/toast.dart';
import '../../../../shared/widgets/toast/toast_type.dart';
import '../../data/models/divination_params.dart';
import '../../data/models/divination_result.dart';

class DivinationResultScreen extends StatefulWidget {
  const DivinationResultScreen({super.key, required this.data});

  final DivinationResultData data;

  @override
  State<DivinationResultScreen> createState() => _DivinationResultScreenState();
}

enum _ResultTransitionStep { preparing, deriving, done }

class _DivinationResultScreenState extends State<DivinationResultScreen> {
  _ResultTransitionStep _step = _ResultTransitionStep.preparing;
  bool _showOverlay = true;

  @override
  void initState() {
    super.initState();
    _playSequence();
  }

  Future<void> _playSequence() async {
    await Future<void>.delayed(const Duration(milliseconds: 420));
    if (!mounted) {
      return;
    }
    setState(() {
      _step = _ResultTransitionStep.deriving;
    });
    await Future<void>.delayed(const Duration(milliseconds: 820));
    if (!mounted) {
      return;
    }
    setState(() {
      _step = _ResultTransitionStep.done;
    });
  }

  void _dismissOverlay() {
    if (_step != _ResultTransitionStep.done) {
      return;
    }
    setState(() {
      _showOverlay = false;
    });
  }

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    final palette = Theme.of(context).extension<AppColorPalette>()!;
    final l10n = AppLocalizations.of(context)!;
    return Scaffold(
      backgroundColor: colors.surface,
      appBar: AppBar(
        backgroundColor: colors.surface,
        surfaceTintColor: colors.surface,
        title: Text(l10n.resultScreenTitle),
        centerTitle: true,
      ),
      body: Stack(
        children: [
          SingleChildScrollView(
            padding: const EdgeInsets.fromLTRB(
              AppSpacing.xl,
              AppSpacing.lg,
              AppSpacing.xl,
              AppSpacing.xl,
            ),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                _ResultHeader(data: widget.data),
                const SizedBox(height: AppSpacing.md),
                _SignCard(signType: widget.data.signType),
                const SizedBox(height: AppSpacing.md),
                _KeywordCard(keywords: widget.data.keywords),
                const SizedBox(height: AppSpacing.md),
                _AnalysisCard(
                  title: l10n.resultConclusion,
                  content: widget.data.conclusion,
                ),
                const SizedBox(height: AppSpacing.md),
                _AnalysisCard(
                  title: l10n.resultAnalysis,
                  content: widget.data.analysis,
                ),
                const SizedBox(height: AppSpacing.md),
                _AnalysisCard(
                  title: l10n.resultSuggestion,
                  content: widget.data.suggestion,
                ),
                const SizedBox(height: AppSpacing.md),
                Container(
                  width: double.infinity,
                  padding: const EdgeInsets.all(AppSpacing.md),
                  decoration: BoxDecoration(
                    color: palette.warningContainer,
                    borderRadius: BorderRadius.circular(AppRadius.md),
                  ),
                  child: Row(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Icon(Icons.warning, color: palette.warning, size: 20),
                      const SizedBox(width: AppSpacing.sm),
                      Expanded(
                        child: Text(
                          l10n.resultWarning,
                          style: Theme.of(context).textTheme.bodyMedium
                              ?.copyWith(
                                color: palette.warning,
                                fontWeight: FontWeight.w600,
                                height: 1.35,
                              ),
                        ),
                      ),
                    ],
                  ),
                ),
                const SizedBox(height: AppSpacing.xl),
                Text(
                  l10n.resultBasicInfo,
                  style: Theme.of(context).textTheme.titleLarge,
                ),
                const SizedBox(height: AppSpacing.md),
                _InfoCard(data: widget.data),
                const SizedBox(height: AppSpacing.xl),
                Text(
                  l10n.resultHexagramDetail,
                  style: Theme.of(context).textTheme.titleLarge,
                ),
                const SizedBox(height: AppSpacing.md),
                _HexagramDetailCard(data: widget.data),
              ],
            ),
          ),
          if (_showOverlay)
            _ResultTransitionOverlay(step: _step, onTapDone: _dismissOverlay),
        ],
      ),
    );
  }
}

class _ResultTransitionOverlay extends StatelessWidget {
  const _ResultTransitionOverlay({required this.step, required this.onTapDone});

  final _ResultTransitionStep step;
  final VoidCallback onTapDone;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    final l10n = AppLocalizations.of(context)!;
    final cardText = switch (step) {
      _ResultTransitionStep.preparing => l10n.transitionPreparing,
      _ResultTransitionStep.deriving => l10n.transitionDeriving,
      _ResultTransitionStep.done => l10n.transitionDone,
    };

    return Positioned.fill(
      child: Material(
        color: colors.surface,
        child: Center(
          child: GestureDetector(
            key: const Key('result_transition_overlay_tap'),
            onTap: onTapDone,
            child: TweenAnimationBuilder<double>(
              key: ValueKey<_ResultTransitionStep>(step),
              tween: Tween<double>(begin: pi / 2, end: 0),
              duration: const Duration(milliseconds: 460),
              curve: Curves.easeOutCubic,
              builder: (context, angle, child) {
                final opacity = (1 - angle / (pi / 2)).clamp(0.0, 1.0);
                return Opacity(
                  opacity: opacity,
                  child: Transform(
                    alignment: Alignment.center,
                    transform: Matrix4.identity()
                      ..setEntry(3, 2, 0.001)
                      ..rotateY(angle),
                    child: child,
                  ),
                );
              },
              child: Container(
                width: 220,
                height: 320,
                decoration: BoxDecoration(
                  color: colors.surface,
                  borderRadius: BorderRadius.circular(AppRadius.lg),
                  border: Border.all(
                    color: colors.primary.withValues(alpha: 0.2),
                  ),
                  boxShadow: [
                    BoxShadow(
                      color: colors.shadow.withValues(alpha: 0.25),
                      blurRadius: 22,
                      offset: const Offset(0, 12),
                    ),
                  ],
                ),
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Icon(
                      step == _ResultTransitionStep.done
                          ? Icons.visibility
                          : Icons.auto_awesome,
                      color: colors.primary,
                      size: 34,
                    ),
                    const SizedBox(height: AppSpacing.md),
                    Text(
                      cardText,
                      textAlign: TextAlign.center,
                      style: Theme.of(context).textTheme.titleMedium?.copyWith(
                        color: colors.primary,
                        fontWeight: FontWeight.w700,
                        height: 1.4,
                      ),
                    ),
                  ],
                ),
              ),
            ),
          ),
        ),
      ),
    );
  }
}

class _ResultHeader extends StatelessWidget {
  const _ResultHeader({required this.data});

  final DivinationResultData data;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    final l10n = AppLocalizations.of(context)!;
    return Row(
      children: [
        Text(
          l10n.resultAIAnalysis,
          style: Theme.of(
            context,
          ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.w700),
        ),
        const Spacer(),
        TextButton(
          onPressed: () {
            final payload = <String, dynamic>{
              'signType': data.signType,
              'question': data.params.question,
              'keywords': data.keywords,
              'conclusion': data.conclusion,
            };
            Clipboard.setData(
              ClipboardData(
                text: const JsonEncoder.withIndent('  ').convert(payload),
              ),
            );
            Toast.show(
              context,
              l10n.toastContentCopied,
              type: ToastType.success,
            );
          },
          style: TextButton.styleFrom(foregroundColor: colors.primary),
          child: Text(l10n.resultShare),
        ),
      ],
    );
  }
}

class _SignCard extends StatelessWidget {
  const _SignCard({required this.signType});

  final String signType;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    final image = switch (signType) {
      '上上签' => 'assets/images/qigua/shangshang.jpg',
      '中上签' => 'assets/images/qigua/zhongshang.jpg',
      _ => 'assets/images/qigua/zhongxia.jpg',
    };
    return Card(
      margin: EdgeInsets.zero,
      color: colors.surface,
      elevation: 2,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(AppRadius.md),
      ),
      child: Padding(
        padding: const EdgeInsets.symmetric(vertical: AppSpacing.lg),
        child: Column(
          children: [
            Image.asset(
              image,
              width: double.infinity,
              height: 220,
              fit: BoxFit.cover,
            ),
            const SizedBox(height: AppSpacing.sm),
            Text(
              signType,
              style: Theme.of(context).textTheme.titleLarge?.copyWith(
                color: colors.primary,
                fontWeight: FontWeight.w700,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _KeywordCard extends StatelessWidget {
  const _KeywordCard({required this.keywords});

  final String keywords;

  @override
  Widget build(BuildContext context) {
    final palette = Theme.of(context).extension<AppColorPalette>()!;
    return Card(
      margin: EdgeInsets.zero,
      color: palette.warningContainer,
      elevation: 0,
      child: Padding(
        padding: const EdgeInsets.all(AppSpacing.lg),
        child: Center(
          child: Text(
            keywords,
            textAlign: TextAlign.center,
            style: Theme.of(context).textTheme.titleMedium?.copyWith(
              color: Theme.of(context).colorScheme.primary,
              fontWeight: FontWeight.w700,
            ),
          ),
        ),
      ),
    );
  }
}

class _AnalysisCard extends StatelessWidget {
  const _AnalysisCard({required this.title, required this.content});

  final String title;
  final String content;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    return Card(
      margin: EdgeInsets.zero,
      color: colors.surface,
      elevation: 2,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(AppRadius.md),
      ),
      child: Padding(
        padding: const EdgeInsets.all(AppSpacing.lg),
        child: Column(
          children: [
            Row(
              children: [
                Text(
                  title,
                  style: Theme.of(context).textTheme.titleMedium?.copyWith(
                    color: colors.primary,
                    fontWeight: FontWeight.w700,
                  ),
                ),
                const Spacer(),
                TextButton(
                  onPressed: () {
                    Clipboard.setData(ClipboardData(text: content));
                    Toast.show(context, '$title已复制', type: ToastType.success);
                  },
                  child: const Text('复制'),
                ),
              ],
            ),
            const SizedBox(height: AppSpacing.sm),
            Text(
              content,
              style: Theme.of(
                context,
              ).textTheme.bodyMedium?.copyWith(height: 1.65),
            ),
          ],
        ),
      ),
    );
  }
}

class _InfoCard extends StatelessWidget {
  const _InfoCard({required this.data});

  final DivinationResultData data;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    return Card(
      margin: EdgeInsets.zero,
      color: colors.surface,
      elevation: 2,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(AppRadius.md),
      ),
      child: Padding(
        padding: const EdgeInsets.all(AppSpacing.lg),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
              '起卦信息',
              style: Theme.of(context).textTheme.titleMedium?.copyWith(
                color: colors.primary,
                fontWeight: FontWeight.w700,
              ),
            ),
            const SizedBox(height: AppSpacing.md),
            _kv(
              context,
              '起卦时间',
              DateFormat(
                'yyyy年MM月dd日 HH:mm',
              ).format(data.params.divinationTime),
            ),
            _kv(
              context,
              '起卦方式',
              data.params.method == DivinationMethod.auto ? '自动起卦' : '手动起卦',
            ),
            _kv(context, '问题类型', _typeLabel(data.params.questionType)),
            _kv(context, '占卜问题', data.params.question),
          ],
        ),
      ),
    );
  }

  Widget _kv(BuildContext context, String k, String v) {
    return Padding(
      padding: const EdgeInsets.only(bottom: AppSpacing.sm),
      child: RichText(
        text: TextSpan(
          style: Theme.of(context).textTheme.bodyMedium,
          children: [
            TextSpan(
              text: '$k：',
              style: TextStyle(
                color: Theme.of(
                  context,
                ).colorScheme.onSurface.withValues(alpha: 0.75),
              ),
            ),
            TextSpan(
              text: v,
              style: TextStyle(
                color: Theme.of(context).colorScheme.onSurface,
                fontWeight: FontWeight.w600,
              ),
            ),
          ],
        ),
      ),
    );
  }

  String _typeLabel(QuestionType type) {
    return switch (type) {
      QuestionType.career => '事业',
      QuestionType.love => '情感',
      QuestionType.wealth => '财富',
      QuestionType.fortune => '运势',
      QuestionType.dream => '解梦',
      QuestionType.health => '健康',
      QuestionType.study => '学业',
      QuestionType.search => '寻物',
      QuestionType.other => '其他',
    };
  }
}

class _HexagramDetailCard extends StatelessWidget {
  const _HexagramDetailCard({required this.data});

  final DivinationResultData data;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    return Column(
      children: [
        Card(
          margin: EdgeInsets.zero,
          color: colors.surface,
          elevation: 2,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(AppRadius.md),
          ),
          child: Padding(
            padding: const EdgeInsets.all(AppSpacing.lg),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  '干支信息',
                  style: Theme.of(context).textTheme.titleMedium?.copyWith(
                    color: colors.primary,
                    fontWeight: FontWeight.w700,
                  ),
                ),
                const SizedBox(height: AppSpacing.md),
                Row(
                  children: [
                    Expanded(
                      child: _miniKV(context, '月建', data.ganzhi.yueJian),
                    ),
                    Expanded(child: _miniKV(context, '日辰', data.ganzhi.riChen)),
                  ],
                ),
                const SizedBox(height: AppSpacing.sm),
                Row(
                  children: [
                    Expanded(child: _miniKV(context, '月破', data.ganzhi.yuePo)),
                    Expanded(
                      child: _miniKV(context, '日冲', data.ganzhi.riChong),
                    ),
                  ],
                ),
                const SizedBox(height: AppSpacing.md),
                Text('五行旺衰', style: Theme.of(context).textTheme.bodyMedium),
                const SizedBox(height: AppSpacing.sm),
                _WuXingTable(data: data),
                const SizedBox(height: AppSpacing.md),
                Text('干支空亡', style: Theme.of(context).textTheme.bodyMedium),
                const SizedBox(height: AppSpacing.sm),
                _KongWangTable(data: data),
              ],
            ),
          ),
        ),
        const SizedBox(height: AppSpacing.md),
        Card(
          margin: EdgeInsets.zero,
          color: colors.surfaceContainerLow,
          elevation: 2,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(AppRadius.md),
          ),
          child: Padding(
            padding: const EdgeInsets.all(AppSpacing.lg),
            child: Column(
              children: [
                Row(
                  children: [
                    Expanded(
                      child: Text(
                        data.guaName,
                        textAlign: TextAlign.center,
                        style: Theme.of(context).textTheme.titleMedium
                            ?.copyWith(fontWeight: FontWeight.w700),
                      ),
                    ),
                    if (data.hasChangingYao)
                      Expanded(
                        child: Text(
                          data.targetGuaName,
                          textAlign: TextAlign.center,
                          style: Theme.of(context).textTheme.titleMedium
                              ?.copyWith(fontWeight: FontWeight.w700),
                        ),
                      ),
                  ],
                ),
                const SizedBox(height: AppSpacing.md),
                for (int idx = 5; idx >= 0; idx--)
                  _YaoDetailRow(
                    line: data.yaoLines[idx],
                    target: data.targetYaoLines[idx],
                    showTarget: data.hasChangingYao,
                  ),
                const SizedBox(height: AppSpacing.sm),
                const Align(
                  alignment: Alignment.centerLeft,
                  child: YaoLegend(),
                ),
              ],
            ),
          ),
        ),
      ],
    );
  }

  Widget _miniKV(BuildContext context, String key, String value) {
    return Row(
      children: [
        Text('$key：'),
        Text(value, style: const TextStyle(fontWeight: FontWeight.w600)),
      ],
    );
  }
}

class _WuXingTable extends StatelessWidget {
  const _WuXingTable({required this.data});

  final DivinationResultData data;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    return Container(
      decoration: BoxDecoration(
        border: Border.all(color: colors.outline),
        borderRadius: BorderRadius.circular(AppRadius.sm),
      ),
      child: Column(
        children: [
          Row(
            children: DivinationTerms.wuXing
                .map(
                  (k) => Expanded(
                    child: Container(
                      padding: const EdgeInsets.symmetric(
                        vertical: AppSpacing.sm,
                      ),
                      decoration: BoxDecoration(
                        color: colors.surfaceContainerHigh,
                        border: Border(
                          right: BorderSide(
                            color: k == DivinationTerms.wuXing.last
                                ? colors.surfaceContainerHigh
                                : colors.outline,
                          ),
                        ),
                      ),
                      child: Text(k, textAlign: TextAlign.center),
                    ),
                  ),
                )
                .toList(),
          ),
          Row(
            children: DivinationTerms.wuXing
                .map(
                  (k) => Expanded(
                    child: Padding(
                      padding: const EdgeInsets.symmetric(
                        vertical: AppSpacing.sm,
                      ),
                      child: Text(
                        data.wuXingStatus[k] ?? '',
                        textAlign: TextAlign.center,
                      ),
                    ),
                  ),
                )
                .toList(),
          ),
        ],
      ),
    );
  }
}

class _KongWangTable extends StatelessWidget {
  const _KongWangTable({required this.data});

  final DivinationResultData data;

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    final rows = [
      ('年', '${data.ganzhi.yearGanZhi}年', data.ganzhi.yearKongWang),
      ('月', '${data.ganzhi.monthGanZhi}月', data.ganzhi.monthKongWang),
      ('日', '${data.ganzhi.dayGanZhi}日', data.ganzhi.dayKongWang),
      ('时', '${data.ganzhi.timeGanZhi}时', data.ganzhi.timeKongWang),
    ];
    return Container(
      decoration: BoxDecoration(
        border: Border.all(color: colors.outline),
        borderRadius: BorderRadius.circular(AppRadius.sm),
      ),
      child: Column(
        children: [
          for (final row in rows)
            Padding(
              padding: const EdgeInsets.symmetric(
                horizontal: AppSpacing.md,
                vertical: AppSpacing.sm,
              ),
              child: Row(
                children: [
                  SizedBox(width: 28, child: Text(row.$1)),
                  Expanded(child: Text(row.$2, textAlign: TextAlign.center)),
                  SizedBox(
                    width: 64,
                    child: Text(row.$3, textAlign: TextAlign.right),
                  ),
                ],
              ),
            ),
        ],
      ),
    );
  }
}

class _YaoDetailRow extends StatelessWidget {
  const _YaoDetailRow({
    required this.line,
    required this.target,
    required this.showTarget,
  });

  final YaoLineData line;
  final YaoLineData target;
  final bool showTarget;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: AppSpacing.sm),
      child: Row(
        children: [
          Expanded(child: _lineCell(context, line, showMark: true)),
          if (showTarget)
            Expanded(child: _lineCell(context, target, showMark: false)),
        ],
      ),
    );
  }

  Widget _lineCell(
    BuildContext context,
    YaoLineData data, {
    required bool showMark,
  }) {
    return Row(
      children: [
        SizedBox(
          width: 20,
          child: Text(data.spirit, textAlign: TextAlign.center),
        ),
        SizedBox(
          width: 28,
          child: Text(data.relation, textAlign: TextAlign.center),
        ),
        SizedBox(
          width: 18,
          child: Text(data.branch, textAlign: TextAlign.center),
        ),
        SizedBox(
          width: 18,
          child: Text(data.element, textAlign: TextAlign.center),
        ),
        const SizedBox(width: AppSpacing.xs),
        Expanded(child: YaoGlyph(type: data.type, height: 6)),
        SizedBox(
          width: 18,
          child: Text(_changeMark(data.type), textAlign: TextAlign.center),
        ),
        SizedBox(
          width: 18,
          child: Text(showMark ? data.mark : '', textAlign: TextAlign.center),
        ),
      ],
    );
  }

  String _changeMark(YaoType type) {
    return type.changeMark;
  }
}