// lib/screens/time_series_screen.dart
import 'package:flutter/material.dart';
import 'package:fl_chart/fl_chart.dart';
import '../services/api_service.dart';
import '../services/calculator.dart';
import '../models/profile.dart';
import '../models/norms.dart';

class TimeSeriesScreen extends StatefulWidget {
  final String? groupName;
  final int? groupId;
  
  const TimeSeriesScreen({super.key, this.groupName, this.groupId});

  @override
  State<TimeSeriesScreen> createState() => _TimeSeriesScreenState();
}

class _TimeSeriesScreenState extends State<TimeSeriesScreen> {
  List<Profile> _profiles = [];
  List<List<int>> _competenceValues = [];
  List<String> _profileNames = [];
  int _selectedCompetence = 0;
  bool _isLoading = true;

  @override
  void initState() {
    super.initState();
    _loadData();
  }

  Future<void> _loadData() async {
    setState(() => _isLoading = true);
    try {
      final apiService = ApiService();
      final allProfiles = await apiService.getProfiles();
      
      List<Profile> filtered;
      if (widget.groupId != null) {
        filtered = allProfiles.where((p) => p.gruppeID == widget.groupId.toString()).toList();
      } else if (widget.groupName != null) {
        filtered = allProfiles.where((p) => p.gruppename == widget.groupName).toList();
      } else {
        filtered = allProfiles;
      }
      
      filtered.sort((a, b) => (a.createdAt ?? DateTime.now()).compareTo(b.createdAt ?? DateTime.now()));
      
      final values = <List<int>>[];
      final names = <String>[];
      
      for (final profile in filtered) {
        final seSums = Calculator.calculateSums(profile.seItems);
        final competenceValues = Calculator.calculateProfileValues(seSums, Norms.normSE_HS);
        values.add(competenceValues);
        names.add(profile.name);
      }
      
      setState(() {
        _profiles = filtered;
        _competenceValues = values;
        _profileNames = names;
        _isLoading = false;
      });
    } catch (e) {
      setState(() => _isLoading = false);
      _showError('Daten konnten nicht geladen werden');
    }
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Zeitreihe - ${widget.groupName ?? 'Alle Profile'}'),
      ),
      body: _isLoading
          ? const Center(child: CircularProgressIndicator())
          : _profiles.isEmpty
              ? const Center(child: Text('Keine Profile in dieser Gruppe'))
              : Column(
                  children: [
                    Padding(
                      padding: const EdgeInsets.all(16),
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          const Text('Kompetenz auswählen:', style: TextStyle(fontWeight: FontWeight.bold)),
                          const SizedBox(height: 8),
                          DropdownButton<int>(
                            value: _selectedCompetence,
                            isExpanded: true,
                            items: List.generate(6, (i) {
                              return DropdownMenuItem(
                                value: i,
                                child: Text(Norms.kompetenzen[i]),
                              );
                            }),
                            onChanged: (value) => setState(() => _selectedCompetence = value!),
                          ),
                        ],
                      ),
                    ),
                    SizedBox(
                      height: 280,
                      child: Padding(
                        padding: const EdgeInsets.all(16),
                        child: LineChart(
                          LineChartData(
                            gridData: const FlGridData(show: true),
                            titlesData: const FlTitlesData(
                              leftTitles: AxisTitles(sideTitles: SideTitles(showTitles: true)),
                              bottomTitles: AxisTitles(sideTitles: SideTitles(showTitles: false)),
                            ),
                            borderData: FlBorderData(show: true),
                            lineBarsData: [
                              LineChartBarData(
                                spots: List.generate(
                                  _competenceValues.length,
                                  (i) => FlSpot(i.toDouble(), _competenceValues[i][_selectedCompetence].toDouble()),
                                ),
                                isCurved: true,
                                color: Colors.blue,
                                barWidth: 2,
                                dotData: const FlDotData(show: true),
                              ),
                            ],
                            minY: 0,
                            maxY: 6,
                          ),
                        ),
                      ),
                    ),
                    const SizedBox(height: 16),
                    const Divider(),
                    Expanded(
                      child: SingleChildScrollView(
                        scrollDirection: Axis.horizontal,
                        child: DataTable(
                          columnSpacing: 12,
                          columns: [
                            const DataColumn(label: Text('Profil')),
                            ...Norms.kompetenzen.map((k) => DataColumn(label: Text(k.substring(0, 8)))),
                          ],
                          rows: List.generate(_profileNames.length, (index) {
                            return DataRow(cells: [
                              DataCell(Text(_profileNames[index])),
                              ..._competenceValues[index].map((v) => DataCell(Text(v.toString()))),
                            ]);
                          }),
                        ),
                      ),
                    ),
                  ],
                ),
    );
  }
}