import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import 'package:arcx/app/app_theme.dart';
import 'package:arcx/data/local/models/models.dart';
import 'package:arcx/features/config/application/app_config_controller.dart';
import 'package:arcx/features/home/presentation/widgets/heatmap_card.dart';
import 'package:arcx/features/home/presentation/widgets/profile_card.dart';
import 'package:arcx/features/home/presentation/widgets/score_distribution_card.dart';
import 'package:arcx/features/home/presentation/widgets/stats_card.dart';
import 'package:arcx/features/iap/presentation/iap_unlock_dialog.dart';
import 'package:arcx/features/profile/presentation/profile_edit_dialog.dart';
import 'package:arcx/features/records/presentation/point_book_list_page.dart';
import 'package:arcx/features/scoring/application/scoring_service.dart';
import 'package:arcx/features/scoring/presentation/point_book_create_page.dart';
import 'package:arcx/features/scoring/presentation/point_book_edit_page.dart';
import 'package:arcx/features/stats/application/stats.dart';

class PointBookHomeScreen extends ConsumerWidget {
  const PointBookHomeScreen({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final statsAsync = ref.watch(statsProvider);
    final configAsync = ref.watch(appConfigProvider);

    return Scaffold(
      backgroundColor: AppTheme.surfaceMuted,
      appBar: AppBar(title: const Text('记分本')),
      body: statsAsync.when(
        loading: () => const Center(child: CircularProgressIndicator()),
        error: (e, _) => Center(child: Text('数据加载失败：$e')),
        data: (stats) => RefreshIndicator(
          onRefresh: () async => ref.invalidate(statsProvider),
          child: ListView(
            padding: const EdgeInsets.fromLTRB(16, 16, 16, 32),
            children: [
              ProfileCard(onEdit: () => _editProfile(context)),
              const SizedBox(height: 12),
              _EntitlementBanner(configAsync: configAsync),
              const SizedBox(height: 12),
              StatsCard(stats: stats),
              const SizedBox(height: 12),
              HeatmapCard(stats: stats),
              const SizedBox(height: 12),
              ScoreDistributionCard(stats: stats),
              const SizedBox(height: 20),
              _EntryButtons(
                onOpenRecords: () => _openRecords(context),
                onStartScoring: () => _startScoring(context, ref),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Future<void> _editProfile(BuildContext context) async {
    await showDialog<void>(
      context: context,
      builder: (_) => const ProfileEditDialog(),
    );
  }

  Future<void> _openRecords(BuildContext context) async {
    await Navigator.of(
      context,
    ).push(MaterialPageRoute<void>(builder: (_) => const PointBookListPage()));
  }

  Future<void> _startScoring(BuildContext context, WidgetRef ref) async {
    final config = ref.read(appConfigProvider).value;
    if (config == null) return;

    // IAP / trial gate.
    // if (!config.canStartScoring) {
    //   await showDialog<void>(
    //     context: context,
    //     builder: (_) => const IapUnlockDialog(),
    //   );
    //   return;
    // }

    // Draft check.
    final notifier = ref.read(pointRecordsProvider.notifier);
    final draft = await notifier.currentDraft();
    if (draft != null && context.mounted) {
      final choice = await _showDraftConfirm(context);
      if (choice == null) return;
      if (choice == true) {
        await _goToEdit(context, draft);
        return;
      }
      await notifier.clearDrafts();
    }

    if (!context.mounted) return;
    await _goToCreate(context);
  }

  Future<void> _goToCreate(BuildContext context) async {
    final created = await Navigator.of(context).push<PointRecord>(
      MaterialPageRoute<PointRecord>(
        builder: (_) => const PointBookCreatePage(),
      ),
    );
    // Create already popped itself before returning, so the stack is [Home]
    // here. A plain push yields [Home, Edit] and back/popUntil lands on Home.
    if (created != null && context.mounted) {
      await _goToEdit(context, created);
    }
  }

  Future<void> _goToEdit(BuildContext context, PointRecord record) async {
    await Navigator.of(context).push(
      MaterialPageRoute<void>(
        builder: (_) => PointBookEditPage(recordId: record.id),
      ),
    );
  }

  Future<bool?> _showDraftConfirm(BuildContext context) {
    return showDialog<bool>(
      context: context,
      builder: (_) => AlertDialog(
        title: const Text('存在未完成草稿'),
        content: const Text('检测到上次有未完成的记分草稿，是否继续编辑？选择“重新计分”将删除该草稿。'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context, false),
            child: const Text('重新计分'),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(context, true),
            child: const Text('继续编辑'),
          ),
        ],
      ),
    );
  }
}

class _EntitlementBanner extends StatelessWidget {
  const _EntitlementBanner({required this.configAsync});
  final AsyncValue<AppConfig> configAsync;

  @override
  Widget build(BuildContext context) {
    return configAsync.when(
      loading: () => const SizedBox.shrink(),
      error: (_, __) => const SizedBox.shrink(),
      data: (config) {
        final unlocked = config.isVipUnlocked;
        return Container(
          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
          decoration: BoxDecoration(
            color: unlocked
                ? AppTheme.primary.withValues(alpha: 0.12)
                : AppTheme.accent.withValues(alpha: 0.18),
            borderRadius: BorderRadius.circular(12),
          ),
          child: Row(
            children: [
              Icon(
                unlocked ? Icons.verified_outlined : Icons.timer_outlined,
                color: unlocked ? AppTheme.primary : AppTheme.accent,
                size: 20,
              ),
              const SizedBox(width: 8),
              Expanded(
                child: Text(
                  unlocked
                      ? '已解锁无限记分权益'
                      : '免费试用剩余 ${config.remainingTrialCount}/${config.freeTrialLimit} 次',
                  style: TextStyle(
                    fontSize: 13,
                    color: unlocked ? AppTheme.primaryDark : AppTheme.accent,
                    fontWeight: FontWeight.w600,
                  ),
                ),
              ),
            ],
          ),
        );
      },
    );
  }
}

class _EntryButtons extends StatelessWidget {
  const _EntryButtons({
    required this.onOpenRecords,
    required this.onStartScoring,
  });
  final VoidCallback onOpenRecords;
  final VoidCallback onStartScoring;

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Expanded(
          child: OutlinedButton.icon(
            onPressed: onOpenRecords,
            icon: const Icon(Icons.list_alt_outlined),
            label: const Text('计分记录'),
          ),
        ),
        const SizedBox(width: 12),
        Expanded(
          child: ElevatedButton.icon(
            onPressed: onStartScoring,
            icon: const Icon(Icons.play_arrow),
            label: const Text('开始记分'),
          ),
        ),
      ],
    );
  }
}