import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../../core/theme/app_theme.dart';
import '../../data/database/app_database.dart';
import '../../data/models/movement_detail.dart';
import '../../providers/database_provider.dart';
import '../../providers/parent_providers.dart';
import 'widgets/child_selector.dart';
import 'widgets/rules_grid.dart';

class ParentSpaceScreen extends ConsumerStatefulWidget {
  const ParentSpaceScreen({super.key});

  @override
  ConsumerState<ParentSpaceScreen> createState() => _ParentSpaceScreenState();
}

class _ParentSpaceScreenState extends ConsumerState<ParentSpaceScreen> {
  int? _selectedChildId;
  bool _isApplying = false;

  void _refreshData() {
    ref.invalidate(childrenProvider);
    ref.invalidate(movementsProvider);
  }

  Future<void> _applyRule(int ruleId) async {
    final childId = _selectedChildId;
    if (childId == null || _isApplying) return;

    setState(() => _isApplying = true);
    try {
      final child = await ref
          .read(parentRepositoryProvider)
          .applyRule(childId, ruleId);

      if (!mounted) return;

      if (child == null) {
        _showFeedback('Erreur lors de l\'application.');
        return;
      }

      _refreshData();
      _showFeedback('${child.prenom} : ${child.score} pts !');
    } finally {
      if (mounted) setState(() => _isApplying = false);
    }
  }

  Future<void> _confirmCancel(MovementDetail movement) async {
    final sign = movement.delta > 0 ? '+' : '';
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('Annuler ce mouvement ?'),
        content: Text(
          'Annuler « ${movement.label} » pour ${movement.childName} '
          '($sign${movement.delta}) ?\nLes points seront recalculés.',
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context, false),
            child: const Text('Non'),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(context, true),
            child: const Text('Oui, annuler'),
          ),
        ],
      ),
    );

    if (confirmed != true || !mounted) return;

    final result = await ref
        .read(parentRepositoryProvider)
        .cancelMovement(movement.id);

    if (!mounted) return;

    if (result == null) {
      _showFeedback('Impossible d\'annuler.');
      return;
    }

    _refreshData();
    _showFeedback('Mouvement annulé');
  }

  void _showFeedback(String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(content: Text(message), duration: const Duration(seconds: 2)),
    );
  }

  @override
  Widget build(BuildContext context) {
    final childrenAsync = ref.watch(childrenProvider);
    final rulesAsync = ref.watch(rulesProvider);
    final movementsAsync = ref.watch(movementsProvider);

    return DecoratedBox(
      decoration: const BoxDecoration(gradient: AppTheme.primaryGradient),
      child: Scaffold(
        backgroundColor: Colors.transparent,
        appBar: AppBar(
          leading: IconButton(
            icon: const Icon(Icons.arrow_back),
            onPressed: () => Navigator.of(context).pop(),
          ),
          title: const Row(
            mainAxisSize: MainAxisSize.min,
            children: [
              Icon(Icons.family_restroom, size: 22),
              SizedBox(width: 8),
              Text('Espace Parents'),
            ],
          ),
          actions: [
            TextButton(
              onPressed: () => Navigator.of(context).pop(),
              child: const Text('Déconnexion'),
            ),
          ],
        ),
        body: childrenAsync.when(
          loading: () => const Center(
            child: CircularProgressIndicator(color: Colors.white),
          ),
          error: (_, _) => const Center(
            child: Text('Erreur', style: TextStyle(color: Colors.white)),
          ),
          data: (children) {
            if (children.isEmpty) {
              return const Center(
                child: Text(
                  'Aucun enfant',
                  style: TextStyle(color: Colors.white),
                ),
              );
            }

            _selectedChildId ??= children.first.id;
            final selected = children.firstWhere(
              (c) => c.id == _selectedChildId,
              orElse: () => children.first,
            );

            return RefreshIndicator(
              onRefresh: () async => _refreshData(),
              child: ListView(
                padding: const EdgeInsets.fromLTRB(16, 0, 16, 24),
                children: [
                  _SectionCard(
                    title: 'Enfant sélectionné',
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.stretch,
                      children: [
                        ChildSelector(
                          children: children,
                          selectedId: selected.id,
                          onSelected: (id) =>
                              setState(() => _selectedChildId = id),
                        ),
                        const SizedBox(height: 12),
                        _ScoreBanner(child: selected),
                      ],
                    ),
                  ),
                  const SizedBox(height: 12),
                  _SectionCard(
                    title: 'Appliquer une règle',
                    child: rulesAsync.when(
                      loading: () => const Center(
                        child: Padding(
                          padding: EdgeInsets.all(24),
                          child: CircularProgressIndicator(),
                        ),
                      ),
                      error: (_, _) => const Text('Erreur de chargement'),
                      data: (rules) {
                        if (rules.isEmpty) {
                          return const Text(
                            'Aucune règle active. Importez le pack par défaut '
                            'ou ajoutez des règles.',
                          );
                        }
                        return RulesGrid(
                          rules: rules,
                          isApplying: _isApplying,
                          onRuleTap: _applyRule,
                        );
                      },
                    ),
                  ),
                  const SizedBox(height: 12),
                  _SectionCard(
                    title: 'Derniers mouvements',
                    child: movementsAsync.when(
                      loading: () => const Center(
                        child: Padding(
                          padding: EdgeInsets.all(24),
                          child: CircularProgressIndicator(),
                        ),
                      ),
                      error: (_, _) => const Text('Erreur de chargement'),
                      data: (movements) => _MovementHistory(
                        movements: movements,
                        onCancel: _confirmCancel,
                      ),
                    ),
                  ),
                ],
              ),
            );
          },
        ),
      ),
    );
  }
}

class _SectionCard extends StatelessWidget {
  const _SectionCard({required this.title, required this.child});

  final String title;
  final Widget child;

  @override
  Widget build(BuildContext context) {
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Text(
              title,
              style: Theme.of(context).textTheme.titleSmall?.copyWith(
                    fontWeight: FontWeight.w700,
                    color: const Color(0xFF667EEA),
                  ),
            ),
            const SizedBox(height: 12),
            child,
          ],
        ),
      ),
    );
  }
}

class _ScoreBanner extends StatelessWidget {
  const _ScoreBanner({required this.child});

  final Enfant child;

  @override
  Widget build(BuildContext context) {
    final color = AppTheme.parseColor(child.couleur);
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
      decoration: BoxDecoration(
        border: Border.all(color: color, width: 2),
        borderRadius: BorderRadius.circular(12),
        color: color.withValues(alpha: 0.08),
      ),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: [
          Text(
            child.prenom,
            style: const TextStyle(fontWeight: FontWeight.w700, fontSize: 16),
          ),
          Text(
            '${child.score} points',
            style: TextStyle(
              fontWeight: FontWeight.bold,
              fontSize: 18,
              color: color,
            ),
          ),
        ],
      ),
    );
  }
}

class _MovementHistory extends StatelessWidget {
  const _MovementHistory({
    required this.movements,
    required this.onCancel,
  });

  final List<MovementDetail> movements;
  final void Function(MovementDetail) onCancel;

  @override
  Widget build(BuildContext context) {
    if (movements.isEmpty) {
      return Text(
        'Aucun mouvement',
        style: TextStyle(color: Colors.grey.shade600),
      );
    }

    return Column(
      children: movements.map((m) {
        final sign = m.delta > 0 ? '+' : '';
        final deltaColor =
            m.delta >= 0 ? Colors.green.shade700 : Colors.red.shade700;

        return Padding(
          padding: const EdgeInsets.symmetric(vertical: 6),
          child: Row(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Expanded(
                child: Text(
                  '${m.icon} ${m.childName} — ${m.label}',
                  style: const TextStyle(fontSize: 14),
                ),
              ),
              Column(
                crossAxisAlignment: CrossAxisAlignment.end,
                children: [
                  Text(
                    '$sign${m.delta}',
                    style: TextStyle(
                      fontWeight: FontWeight.bold,
                      color: deltaColor,
                    ),
                  ),
                  Text(
                    _formatDate(m.createdAt),
                    style: TextStyle(fontSize: 11, color: Colors.grey.shade600),
                  ),
                ],
              ),
              IconButton(
                icon: const Icon(Icons.close, size: 20),
                color: Colors.grey.shade600,
                tooltip: 'Annuler',
                onPressed: () => onCancel(m),
              ),
            ],
          ),
        );
      }).toList(),
    );
  }

  static String _formatDate(DateTime dt) {
    final local = dt.toLocal();
    String two(int n) => n.toString().padLeft(2, '0');
    return '${two(local.day)}/${two(local.month)} '
        '${two(local.hour)}:${two(local.minute)}';
  }
}