import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:intl/intl.dart';
import '../../models/time_registration.dart';
import '../../providers/auth_provider.dart';
import '../../providers/time_provider.dart';

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

  @override
  ConsumerState<ManualEntryScreen> createState() => _ManualEntryScreenState();
}

class _ManualEntryScreenState extends ConsumerState<ManualEntryScreen> {
  final _formKey = GlobalKey<FormState>();
  final _commentController = TextEditingController();
  final _projectController = TextEditingController();
  final _customerController = TextEditingController();
  
  late DateTime _selectedDate;
  late TimeOfDay _startTime;
  late TimeOfDay _endTime;
  RegistrationType _selectedType = RegistrationType.ordinary;
  bool _isLoading = false;

  @override
  void initState() {
    super.initState();
    _selectedDate = DateTime.now();
    _startTime = const TimeOfDay(hour: 8, minute: 0);
    _endTime = const TimeOfDay(hour: 16, minute: 0);
  }

  @override
  void dispose() {
    _commentController.dispose();
    _projectController.dispose();
    _customerController.dispose();
    super.dispose();
  }

  Future<void> _selectDate(BuildContext context) async {
    final DateTime? picked = await showDatePicker(
      context: context,
      initialDate: _selectedDate,
      firstDate: DateTime(2020),
      lastDate: DateTime.now(),
      locale: const Locale('nb', 'NO'),
    );
    if (picked != null && picked != _selectedDate) {
      setState(() {
        _selectedDate = picked;
      });
    }
  }

  Future<void> _selectTime(BuildContext context, bool isStart) async {
    final TimeOfDay? picked = await showTimePicker(
      context: context,
      initialTime: isStart ? _startTime : _endTime,
      builder: (context, child) {
        return MediaQuery(
          data: MediaQuery.of(context).copyWith(alwaysUse24HourFormat: true),
          child: child!,
        );
      },
    );
    if (picked != null) {
      setState(() {
        if (isStart) {
          _startTime = picked;
        } else {
          _endTime = picked;
        }
      });
    }
  }

  Future<void> _saveRegistration() async {
    if (!_formKey.currentState!.validate()) return;

    setState(() => _isLoading = true);

    try {
      final user = ref.read(currentUserProvider);
      final userData = await ref.read(userDataProvider.future);
      
      if (user == null || userData == null) {
        throw Exception('Ingen brukerdata funnet');
      }

      final startDateTime = DateTime(
        _selectedDate.year,
        _selectedDate.month,
        _selectedDate.day,
        _startTime.hour,
        _startTime.minute,
      );

      var endDateTime = DateTime(
        _selectedDate.year,
        _selectedDate.month,
        _selectedDate.day,
        _endTime.hour,
        _endTime.minute,
      );

      // Håndter nattarbeid (hvis slutt er før start, antar vi neste dag)
      if (endDateTime.isBefore(startDateTime)) {
        endDateTime = endDateTime.add(const Duration(days: 1));
      }

      final timeService = ref.read(timeServiceProvider);
      await timeService.createManualEntry(
        userId: user.uid,
        organizationId: userData.organizationId,
        startTime: startDateTime,
        endTime: endDateTime,
        type: _selectedType,
        projectId: _projectController.text.isNotEmpty ? _projectController.text : null,
        customerId: _customerController.text.isNotEmpty ? _customerController.text : null,
        comment: _commentController.text.isNotEmpty ? _commentController.text : null,
      );

      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Timeregistrering lagret')),
        );
        Navigator.pop(context);
        
        // Oppdater lister
        ref.invalidate(todayRegistrationsProvider);
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Feil: $e')),
        );
      }
    } finally {
      if (mounted) {
        setState(() => _isLoading = false);
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Manuell registrering'),
      ),
      body: SingleChildScrollView(
        padding: const EdgeInsets.all(16.0),
        child: Form(
          key: _formKey,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              // Dato
              ListTile(
                title: const Text('Dato'),
                subtitle: Text(DateFormat('EEEE d. MMMM yyyy', 'nb_NO').format(_selectedDate)),
                leading: const Icon(Icons.calendar_today),
                onTap: () => _selectDate(context),
                shape: RoundedRectangleBorder(
                  borderRadius: BorderRadius.circular(12),
                  side: BorderSide(color: Colors.grey.shade300),
                ),
              ),
              const SizedBox(height: 16),

              // Tidspunkt
              Row(
                children: [
                  Expanded(
                    child: ListTile(
                      title: const Text('Start'),
                      subtitle: Text(_startTime.format(context)),
                      leading: const Icon(Icons.access_time),
                      onTap: () => _selectTime(context, true),
                      shape: RoundedRectangleBorder(
                        borderRadius: BorderRadius.circular(12),
                        side: BorderSide(color: Colors.grey.shade300),
                      ),
                    ),
                  ),
                  const SizedBox(width: 16),
                  Expanded(
                    child: ListTile(
                      title: const Text('Slutt'),
                      subtitle: Text(_endTime.format(context)),
                      leading: const Icon(Icons.access_time_filled),
                      onTap: () => _selectTime(context, false),
                      shape: RoundedRectangleBorder(
                        borderRadius: BorderRadius.circular(12),
                        side: BorderSide(color: Colors.grey.shade300),
                      ),
                    ),
                  ),
                ],
              ),
              const SizedBox(height: 16),

              // Type arbeid
              DropdownButtonFormField<RegistrationType>(
                value: _selectedType,
                decoration: const InputDecoration(
                  labelText: 'Type arbeid',
                  prefixIcon: Icon(Icons.category),
                ),
                items: RegistrationType.values.map((type) {
                  return DropdownMenuItem(
                    value: type,
                    child: Text(_getTypeDisplayName(type)),
                  );
                }).toList(),
                onChanged: (value) {
                  if (value != null) {
                    setState(() => _selectedType = value);
                  }
                },
              ),
              const SizedBox(height: 16),

              // Prosjekt og Kunde
              TextFormField(
                controller: _customerController,
                decoration: const InputDecoration(
                  labelText: 'Kunde (valgfritt)',
                  prefixIcon: Icon(Icons.business),
                ),
              ),
              const SizedBox(height: 16),
              
              TextFormField(
                controller: _projectController,
                decoration: const InputDecoration(
                  labelText: 'Prosjekt (valgfritt)',
                  prefixIcon: Icon(Icons.folder),
                ),
              ),
              const SizedBox(height: 16),

              // Kommentar
              TextFormField(
                controller: _commentController,
                decoration: const InputDecoration(
                  labelText: 'Kommentar (valgfritt)',
                  prefixIcon: Icon(Icons.comment),
                ),
                maxLines: 3,
              ),
              const SizedBox(height: 32),

              // Lagre knapp
              FilledButton(
                onPressed: _isLoading ? null : _saveRegistration,
                style: FilledButton.styleFrom(
                  padding: const EdgeInsets.symmetric(vertical: 16),
                ),
                child: _isLoading
                    ? const SizedBox(
                        height: 20,
                        width: 20,
                        child: CircularProgressIndicator(strokeWidth: 2),
                      )
                    : const Text('Lagre registrering'),
              ),
            ],
          ),
        ),
      ),
    );
  }

  String _getTypeDisplayName(RegistrationType type) {
    switch (type) {
      case RegistrationType.ordinary:
        return 'Ordinær arbeidstid';
      case RegistrationType.overtime:
        return 'Overtid';
      case RegistrationType.oncall:
        return 'Beredskap/Vakt';
      case RegistrationType.travel:
        return 'Reisetid';
    }
  }
}