import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:intl/intl.dart';
import 'package:supabase_flutter/supabase_flutter.dart';
import '/core/supabase_client.dart';
import '/models/child.dart';

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

  @override
  ConsumerState<AttendanceScreen> createState() => _AttendanceScreenState();
}

class _AttendanceScreenState extends ConsumerState<AttendanceScreen> {
  DateTime _selectedDate = DateTime.now();
  final Map<String, bool> _presence = {};
  final Map<String, String?> _timeIn = {};
  bool _isSaving = false;

  Future<void> _pickDate() async {
    final picked = await showDatePicker(
      context: context,
      initialDate: _selectedDate,
      firstDate: DateTime(2024),
      lastDate: DateTime.now(),
      builder: (c, child) => Theme(
        data: ThemeData.dark()
            .copyWith(colorScheme: const ColorScheme.dark(primary: Color(0xFF4FC3F7))),
        child: child!,
      ),
    );
    if (picked != null) setState(() => _selectedDate = picked);
  }

  Future<void> _markAllPresent(List<Child> children) async {
    setState(() {
      for (final c in children) {
        _presence[c.id] = true;
      }
    });
  }

  Future<void> _saveAttendance(List<Child> children) async {
    setState(() => _isSaving = true);
    final supabase = ref.read(supabaseProvider);
    final today = _selectedDate.toIso8601String().split('T')[0];
    try {
      for (final child in children) {
        final isPresent = _presence[child.id] ?? false;
        await supabase.from('attendance').upsert({
          'child_id': child.id,
          'date': today,
          'status': isPresent ? 'present' : 'absent',
          'time_in': _timeIn[child.id],
        });
      }
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(
            content: Text('Presença guardada com sucesso!'),
            backgroundColor: Color(0xFFA5D6A7),
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text('Erro: $e'), backgroundColor: Colors.red));
      }
    } finally {
      if (mounted) setState(() => _isSaving = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final supabase = ref.read(supabaseProvider);

    return Scaffold(
      backgroundColor: const Color(0xFF1A1A2E),
      appBar: AppBar(
        backgroundColor: const Color(0xFF16213E),
        title: const Text('Presença',
            style: TextStyle(color: Color(0xFF4FC3F7))),
      ),
      body: Column(
        children: [
          // Header: data + filtro
          Container(
            padding: const EdgeInsets.all(16),
            color: const Color(0xFF16213E),
            child: Row(
              children: [
                const Icon(Icons.calendar_today, color: Color(0xFF4FC3F7)),
                const SizedBox(width: 10),
                Text(
                  DateFormat('d MMMM yyyy', 'pt_PT').format(_selectedDate),
                  style: const TextStyle(
                      color: Colors.white,
                      fontWeight: FontWeight.bold,
                      fontSize: 15),
                ),
                const Spacer(),
                TextButton(
                  onPressed: _pickDate,
                  child: const Text('Alterar',
                      style: TextStyle(color: Color(0xFF4FC3F7))),
                ),
              ],
            ),
          ),

          // Lista de crianças
          Expanded(
            child: StreamBuilder<List<Map<String, dynamic>>>(
              stream: supabase.from('children').stream(primaryKey: ['id']),
              builder: (context, snapshot) {
                if (!snapshot.hasData) {
                  return const Center(
                      child: CircularProgressIndicator(
                          color: Color(0xFF4FC3F7)));
                }
                final children = snapshot.data!.map(Child.fromMap).toList();

                return Column(
                  children: [
                    // Botão marcar todos
                    Padding(
                      padding: const EdgeInsets.symmetric(
                          horizontal: 16, vertical: 8),
                      child: ElevatedButton.icon(
                        icon: const Icon(Icons.check_circle_outline,
                            color: Colors.white),
                        label: const Text('Marcar Todos Presentes',
                            style: TextStyle(color: Colors.white)),
                        style: ElevatedButton.styleFrom(
                          backgroundColor: const Color(0xFFA5D6A7),
                          minimumSize: const Size(double.infinity, 46),
                          shape: RoundedRectangleBorder(
                              borderRadius: BorderRadius.circular(12)),
                        ),
                        onPressed: () => _markAllPresent(children),
                      ),
                    ),
                    Expanded(
                      child: ListView.builder(
                        padding: const EdgeInsets.symmetric(horizontal: 16),
                        itemCount: children.length,
                        itemBuilder: (context, i) {
                          final child = children[i];
                          final isPresent = _presence[child.id] ?? false;
                          return Container(
                            margin: const EdgeInsets.only(bottom: 8),
                            padding: const EdgeInsets.symmetric(
                                horizontal: 14, vertical: 10),
                            decoration: BoxDecoration(
                              color: const Color(0xFF16213E),
                              borderRadius: BorderRadius.circular(14),
                              border: Border.all(
                                color: isPresent
                                    ? const Color(0xFFA5D6A7).withOpacity(0.5)
                                    : const Color(0xFF333366),
                              ),
                            ),
                            child: Row(
                              children: [
                                CircleAvatar(
                                  radius: 20,
                                  backgroundImage: child.photoUrl != null
                                      ? NetworkImage(child.photoUrl!)
                                      : null,
                                  backgroundColor:
                                      const Color(0xFF4FC3F7).withOpacity(0.2),
                                  child: child.photoUrl == null
                                      ? const Icon(Icons.child_care,
                                          color: Color(0xFF4FC3F7), size: 20)
                                      : null,
                                ),
                                const SizedBox(width: 12),
                                Expanded(
                                  child: Column(
                                    crossAxisAlignment:
                                        CrossAxisAlignment.start,
                                    children: [
                                      Text(child.fullName,
                                          style: const TextStyle(
                                              color: Colors.white,
                                              fontWeight: FontWeight.bold)),
                                      Text(child.classId,
                                          style: const TextStyle(
                                              color: Color(0xFF888888),
                                              fontSize: 12)),
                                    ],
                                  ),
                                ),
                                Switch(
                                  value: isPresent,
                                  activeColor: const Color(0xFFA5D6A7),
                                  onChanged: (v) => setState(
                                      () => _presence[child.id] = v),
                                ),
                              ],
                            ),
                          );
                        },
                      ),
                    ),
                    Padding(
                      padding: const EdgeInsets.all(16),
                      child: ElevatedButton.icon(
                        icon: _isSaving
                            ? const SizedBox(
                                height: 18,
                                width: 18,
                                child: CircularProgressIndicator(
                                    color: Colors.white, strokeWidth: 2))
                            : const Icon(Icons.save, color: Colors.white),
                        label: Text(
                          _isSaving ? 'A guardar...' : 'Guardar Presenças',
                          style: const TextStyle(color: Colors.white),
                        ),
                        style: ElevatedButton.styleFrom(
                          backgroundColor: const Color(0xFF4FC3F7),
                          minimumSize: const Size(double.infinity, 50),
                          shape: RoundedRectangleBorder(
                              borderRadius: BorderRadius.circular(12)),
                        ),
                        onPressed: _isSaving
                            ? null
                            : () => _saveAttendance(children),
                      ),
                    ),
                  ],
                );
              },
            ),
          ),
        ],
      ),
    );
  }
}