import 'package:flutter/material.dart';
import '../models/profile.dart';
import '../models/group.dart';
import '../models/norms.dart';
import '../services/api_service.dart';
import '../services/session_manager.dart';
import '../widgets/item_rating_card.dart';
import '../widgets/loading_spinner.dart';

class ProfileEditScreen extends StatefulWidget {
  final Profile? profile;

  const ProfileEditScreen({super.key, this.profile});

  @override
  State<ProfileEditScreen> createState() => _ProfileEditScreenState();
}

class _ProfileEditScreenState extends State<ProfileEditScreen>
    with SingleTickerProviderStateMixin {
  late TabController _tabController;
  final _nameController = TextEditingController();
  Group? _selectedGroup;
  String _newGroupName = '';
  List<Group> _groups = [];
  List<int> _seItems = List.filled(36, 2);
  List<int> _feItems = List.filled(36, 2);
  bool _isLoading = true;
  bool _isSaving = false;
  bool _showNewGroupField = false;

  @override
  void initState() {
    super.initState();
    _tabController = TabController(length: 2, vsync: this);
    if (widget.profile != null) {
      _nameController.text = widget.profile!.name;
      _seItems = List.from(widget.profile!.seItems);
      _feItems = List.from(widget.profile!.feItems);
    }
    _loadGroups();
  }

  Future<void> _loadGroups() async {
    try {
      final apiService = ApiService();
      final groups = await apiService.getGroups();
      setState(() {
        _groups = groups;
        if (widget.profile?.gruppeID != null) {
          _selectedGroup = groups.firstWhere(
            (g) => g.gruppeID.toString() == widget.profile!.gruppeID,
            orElse: () => groups.first,
          );
        }
        _isLoading = false;
      });
    } catch (e) {
      setState(() => _isLoading = false);
      _showError('Gruppen konnten nicht geladen werden');
    }
  }

  Future<void> _save() async {
    if (_nameController.text.trim().isEmpty) {
      _showError('Bitte geben Sie einen Namen ein');
      return;
    }

    setState(() => _isSaving = true);

    int? finalGroupId;

    if (_showNewGroupField && _newGroupName.trim().isNotEmpty) {
      try {
        final apiService = ApiService();
        final success = await apiService.createGroup(_newGroupName.trim());
        if (success) {
          final updatedGroups = await apiService.getGroups();
          final newGroup = updatedGroups.firstWhere(
            (g) => g.name == _newGroupName.trim(),
          );
          finalGroupId = newGroup.gruppeID;
        }
      } catch (e) {
        _showError('Gruppe konnte nicht erstellt werden');
        setState(() => _isSaving = false);
        return;
      }
    } else if (_selectedGroup != null) {
      finalGroupId = _selectedGroup!.gruppeID;
    }

    final profile = Profile(
      profilID: widget.profile?.profilID ?? '',
      name: _nameController.text.trim(),
      gruppename: _selectedGroup?.name ?? (_newGroupName.trim().isNotEmpty ? _newGroupName.trim() : null),
      gruppeID: finalGroupId?.toString(),
      seItems: _seItems,
      feItems: _feItems,
    );

    try {
      final apiService = ApiService();
      bool success;

      if (widget.profile != null) {
        success = await apiService.updateProfile(profile);
      } else {
        success = await apiService.createProfile(profile);
      }

      if (success && mounted) {
        Navigator.pop(context, true);
      } else {
        _showError('Speichern fehlgeschlagen');
      }
    } catch (e) {
      _showError('Fehler: $e');
    } finally {
      if (mounted) setState(() => _isSaving = false);
    }
  }

  void _showError(String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(content: Text(message), backgroundColor: Colors.red),
    );
  }

  @override
  Widget build(BuildContext context) {
    if (_isLoading) {
      return const Scaffold(body: LoadingSpinner());
    }

    return Scaffold(
      appBar: AppBar(
        title: Text(widget.profile == null ? 'Neues Profil' : 'Profil bearbeiten'),
        bottom: TabBar(
          controller: _tabController,
          tabs: const [
            Tab(text: 'Selbsteinschätzung'),
            Tab(text: 'Fremdeinschätzung'),
          ],
        ),
      ),
      body: Column(
        children: [
          Padding(
            padding: const EdgeInsets.all(16),
            child: Column(
              children: [
                TextField(
                  controller: _nameController,
                  decoration: const InputDecoration(
                    labelText: 'Name *',
                    border: OutlineInputBorder(),
                  ),
                ),
                const SizedBox(height: 12),
                if (!_showNewGroupField)
                  DropdownButtonFormField<Group>(
                    value: _selectedGroup,
                    decoration: const InputDecoration(
                      labelText: 'Gruppe',
                      border: OutlineInputBorder(),
                    ),
                    items: [
                      const DropdownMenuItem(value: null, child: Text('Keine Gruppe')),
                      ..._groups.map((g) => DropdownMenuItem(value: g, child: Text(g.name))),
                      const DropdownMenuItem(value: null, child: Text('+ Neue Gruppe...')),
                    ],
                    onChanged: (value) {
                      if (value == null && _selectedGroup != null) {
                        setState(() {
                          _showNewGroupField = true;
                          _selectedGroup = null;
                        });
                      } else {
                        setState(() => _selectedGroup = value);
                      }
                    },
                  ),
                if (_showNewGroupField)
                  Column(
                    children: [
                      TextField(
                        decoration: const InputDecoration(
                          labelText: 'Neue Gruppe',
                          border: OutlineInputBorder(),
                        ),
                        onChanged: (value) => _newGroupName = value,
                      ),
                      TextButton(
                        onPressed: () => setState(() => _showNewGroupField = false),
                        child: const Text('Abbrechen'),
                      ),
                    ],
                  ),
              ],
            ),
          ),
          Expanded(
            child: TabBarView(
              controller: _tabController,
              children: [
                _buildItemsList(_seItems, true),
                _buildItemsList(_feItems, false),
              ],
            ),
          ),
        ],
      ),
      bottomNavigationBar: BottomAppBar(
        child: Padding(
          padding: const EdgeInsets.all(16),
          child: Row(
            children: [
              Expanded(
                child: OutlinedButton(
                  onPressed: () => Navigator.pop(context),
                  child: const Text('Abbrechen'),
                ),
              ),
              const SizedBox(width: 16),
              Expanded(
                child: ElevatedButton(
                  onPressed: _isSaving ? null : _save,
                  child: _isSaving
                      ? const SizedBox(
                          height: 20,
                          width: 20,
                          child: CircularProgressIndicator(strokeWidth: 2),
                        )
                      : const Text('Speichern'),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Widget _buildItemsList(List<int> items, bool isSE) {
    return ListView.builder(
      padding: const EdgeInsets.all(16),
      itemCount: 36,
      itemBuilder: (context, index) {
        return ItemRatingCard(
          index: index,
          itemName: Norms.items[index],
          value: items[index],
          onChanged: (newValue) {
            setState(() {
              if (isSE) {
                _seItems[index] = newValue;
              } else {
                _feItems[index] = newValue;
              }
            });
          },
        );
      },
    );
  }
}