import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:fl_chart/fl_chart.dart'; // La librairie pour les courbes
import '../../data/models/session.dart';
import '../../data/repositories/session_repository.dart';
import '../../services/statistics_service.dart';

class StatisticsScreen extends StatefulWidget {
  final Session? singleSession;

  const StatisticsScreen({super.key, this.singleSession});

  @override
  State<StatisticsScreen> createState() => _StatisticsScreenState();
}

class _StatisticsScreenState extends State<StatisticsScreen> {
  final StatisticsService _statisticsService = StatisticsService();
  StatsPeriod _selectedPeriod = StatsPeriod.all;
  SessionStatistics? _statistics;
  bool _isLoading = true;
  List<Session> _allSessions = [];

  // Valeurs pour les Dropdowns (Filtres)
  String _selectedWeapon = 'Toutes';
  String _selectedDistance = 'Toutes';

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addPostFrameCallback((_) => _loadStatistics());
  }

  Future<void> _loadStatistics() async {
    if (!mounted) return;
    setState(() => _isLoading = true);
    try {
      final repository = context.read<SessionRepository>();
      _allSessions = await repository.getAllSessions();
      _calculateStats();
    } catch (e) {
      debugPrint('Error: $e');
    } finally {
      if (mounted) setState(() => _isLoading = false);
    }
  }

  void _calculateStats() {
    _statistics = _statisticsService.calculateStatistics(
      _allSessions,
      period: _selectedPeriod,
    );
  }

  List<double> _getScoreHistory() {
    if (_statistics == null || _statistics!.sessions.isEmpty) return [0];
    // Sort sessions by date and take last 10
    final sortedSessions = List<Session>.from(_statistics!.sessions)
      ..sort((a, b) => a.createdAt.compareTo(b.createdAt));
    return sortedSessions.map((s) => s.totalScore.toDouble()).toList();
  }

  List<double> _getPrecisionHistory() {
    if (_statistics == null || _statistics!.sessions.isEmpty) return [0];
    // We would need to calculate precision for each session individually to have a history.
    // For now, let's just use the score trend as a proxy if we don't have per-session precision cached.
    // Actually, let's use the scores but normalized if possible.
    final sortedSessions = List<Session>.from(_statistics!.sessions)
      ..sort((a, b) => a.createdAt.compareTo(b.createdAt));
    return sortedSessions.map((s) {
      if (s.shots.isEmpty) return 0.0;
      // Simple precision proxy: score / max possible (assuming 10 is max)
      return (s.totalScore / (s.shots.length * 10)) * 100;
    }).toList();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: const Color(
        0xFF121212,
      ), // Fond sombre comme sur le design
      appBar: AppBar(
        backgroundColor: Colors.transparent,
        elevation: 0,
        leading: IconButton(
          icon: const Icon(Icons.arrow_back, color: Colors.white),
          onPressed: () => Navigator.pop(context),
        ),
        title: const Text(
          'Statistiques',
          style: TextStyle(color: Colors.white),
        ),
        centerTitle: true,
      ),
      body: _isLoading
          ? const Center(child: CircularProgressIndicator())
          : SingleChildScrollView(
              padding: const EdgeInsets.all(16),
              child: Column(
                children: [
                  // 1. FILTRES (Arme et Distance)
                  Row(
                    children: [
                      Expanded(
                        child: _buildDropdown('Arme utilisée', _selectedWeapon),
                      ),
                      const SizedBox(width: 12),
                      Expanded(
                        child: _buildDropdown('Distance', _selectedDistance),
                      ),
                    ],
                  ),
                  const SizedBox(height: 20),

                  // 2. DONNÉES RAPIDES (Tirs et Sessions)
                  Row(
                    children: [
                      Expanded(
                        child: _buildQuickStat(
                          'Nbre de tirs',
                          '${_statistics?.totalShots ?? 0}',
                          Icons.gps_fixed,
                        ),
                      ),
                      const SizedBox(width: 12),
                      Expanded(
                        child: _buildQuickStat(
                          'Nbre de sessions',
                          '${_statistics?.sessions.length ?? 0}',
                          Icons.analytics,
                        ),
                      ),
                    ],
                  ),
                  const SizedBox(height: 25),

                  // 3. LES GRAPHIQUES
                  _buildChartSection(
                    'Score',
                    '${_statistics?.totalScore ?? 0}',
                    _getScoreHistory(),
                  ),
                  const SizedBox(height: 20),
                  _buildChartSection(
                    'Précision',
                    '${_statistics?.precision.precisionScore.toStringAsFixed(1)}%',
                    _getPrecisionHistory(),
                  ),
                  const SizedBox(height: 20),
                  _buildChartSection(
                    'Groupement moyen',
                    '${(_statistics?.precision.groupingDiameter ?? 0 * 100).toStringAsFixed(1)}%',
                    _getScoreHistory().map((e) => e / 10).toList(), // Proxy for grouping history
                  ),

                  const SizedBox(height: 25),

                  // 4. DISTRIBUTION ET BIAIS (Restauré)
                  if (_statistics != null && _statistics!.totalShots > 0) ...[
                    _buildRegionalDistribution(),
                    const SizedBox(height: 20),
                    _buildQuadrantGrid(),
                    const SizedBox(height: 20),
                    if (_statistics!.regional.biasX.abs() > 0.05 ||
                        _statistics!.regional.biasY.abs() > 0.05)
                      _buildBiasWarning(),
                  ],

                  const SizedBox(height: 30),

                  // 4. BOUTON ACCUEIL
                  SizedBox(
                    width: double.infinity,
                    height: 50,
                    child: ElevatedButton(
                      style: ElevatedButton.styleFrom(
                        backgroundColor: const Color(0xFF1A73E8),
                        shape: RoundedRectangleBorder(
                          borderRadius: BorderRadius.circular(8),
                        ),
                      ),
                      onPressed: () => Navigator.of(
                        context,
                      ).popUntil((route) => route.isFirst),
                      child: const Text(
                        'ACCUEIL',
                        style: TextStyle(
                          color: Colors.white,
                          fontWeight: FontWeight.bold,
                        ),
                      ),
                    ),
                  ),
                ],
              ),
            ),
    );
  }

  // Widget pour les Dropdowns de filtres
  Widget _buildDropdown(String label, String value) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 4),
      decoration: BoxDecoration(
        color: const Color(0xFF1E1E1E),
        borderRadius: BorderRadius.circular(8),
        border: Border.all(color: Colors.white12),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            label,
            style: const TextStyle(color: Colors.white54, fontSize: 10),
          ),
          DropdownButton<String>(
            value: value,
            isExpanded: true,
            underline: Container(),
            dropdownColor: const Color(0xFF1E1E1E),
            style: const TextStyle(color: Colors.white, fontSize: 14),
            items: [value]
                .map(
                  (String val) =>
                      DropdownMenuItem(value: val, child: Text(val)),
                )
                .toList(),
            onChanged: (newValue) {},
          ),
        ],
      ),
    );
  }

  // Widget pour les petites cartes de stats
  Widget _buildQuickStat(String label, String value, IconData icon) {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: const Color(0xFF1E1E1E),
        borderRadius: BorderRadius.circular(12),
      ),
      child: Column(
        children: [
          Icon(icon, color: const Color(0xFF1A73E8), size: 20),
          const SizedBox(height: 8),
          Text(
            value,
            style: const TextStyle(
              color: Colors.white,
              fontSize: 20,
              fontWeight: FontWeight.bold,
            ),
          ),
          Text(
            label,
            style: const TextStyle(color: Colors.white54, fontSize: 12),
          ),
        ],
      ),
    );
  }

  // Widget pour une section de graphique
  Widget _buildChartSection(
    String title,
    String value,
    List<double> dataPoints,
  ) {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: const Color(0xFF1E1E1E),
        borderRadius: BorderRadius.circular(12),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            title,
            style: const TextStyle(color: Colors.white70, fontSize: 14),
          ),
          const SizedBox(height: 10),
          Row(
            children: [
              Text(
                value,
                style: const TextStyle(
                  color: Colors.white,
                  fontSize: 24,
                  fontWeight: FontWeight.bold,
                ),
              ),
              const SizedBox(width: 20),
              Expanded(
                child: SizedBox(
                  height: 60,
                  child: LineChart(_mainChartData(dataPoints)),
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }

  LineChartData _mainChartData(List<double> points) {
    if (points.isEmpty) points = [0];
    return LineChartData(
      gridData: const FlGridData(show: false),
      titlesData: const FlTitlesData(show: false),
      borderData: FlBorderData(show: false),
      lineBarsData: [
        LineChartBarData(
          spots: points.length == 1
              ? [const FlSpot(0, 0), FlSpot(1, points[0])]
              : points
                  .asMap()
                  .entries
                  .map((e) => FlSpot(e.key.toDouble(), e.value))
                  .toList(),
          isCurved: true,
          color: const Color(0xFF4CAF50), // Vert comme sur ton design
          barWidth: 3,
          isStrokeCapRound: true,
          dotData: const FlDotData(show: false),
          belowBarData: BarAreaData(
            show: true,
            color: const Color(0xFF4CAF50).withOpacity(0.2),
          ),
        ),
      ],
    );
  }

  // --- NOUVEAUX WIDGETS RESTAURÉS ---

  Widget _buildRegionalDistribution() {
    final regional = _statistics!.regional;
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: const Color(0xFF1E1E1E),
        borderRadius: BorderRadius.circular(12),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          const Text(
            'Distribution Régionale',
            style: TextStyle(
              color: Colors.white,
              fontSize: 16,
              fontWeight: FontWeight.bold,
            ),
          ),
          const SizedBox(height: 12),
          Row(
            children: [
              const Icon(Icons.explore, color: Color(0xFF1A73E8), size: 20),
              const SizedBox(width: 8),
              Text(
                'Direction dominante : ${regional.dominantDirection}',
                style: const TextStyle(color: Colors.white70, fontSize: 14),
              ),
            ],
          ),
          const SizedBox(height: 12),
          Wrap(
            spacing: 8,
            runSpacing: 8,
            children: regional.sectorDistribution.entries
                .where((e) => e.value > 0)
                .map((e) {
              final percentage = (e.value / _statistics!.totalShots * 100);
              return Container(
                padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
                decoration: BoxDecoration(
                  color: const Color(0xFF1A73E8).withOpacity(0.1),
                  borderRadius: BorderRadius.circular(20),
                  border: Border.all(color: const Color(0xFF1A73E8).withOpacity(0.3)),
                ),
                child: Text(
                  '${e.key}: ${e.value} (${percentage.toStringAsFixed(0)}%)',
                  style: const TextStyle(color: Colors.white, fontSize: 12),
                ),
              );
            }).toList(),
          ),
        ],
      ),
    );
  }

  Widget _buildQuadrantGrid() {
    final quadrants = _statistics!.regional.quadrantDistribution;
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: const Color(0xFF1E1E1E),
        borderRadius: BorderRadius.circular(12),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          const Text(
            'Répartition par Quadrant',
            style: TextStyle(
              color: Colors.white,
              fontSize: 16,
              fontWeight: FontWeight.bold,
            ),
          ),
          const SizedBox(height: 16),
          AspectRatio(
            aspectRatio: 1,
            child: GridView.count(
              crossAxisCount: 2,
              mainAxisSpacing: 4,
              crossAxisSpacing: 4,
              shrinkWrap: true,
              physics: const NeverScrollableScrollPhysics(),
              children: [
                _buildQuadrantCell('Haut-Gauche', quadrants['Haut-Gauche'] ?? 0),
                _buildQuadrantCell('Haut-Droite', quadrants['Haut-Droite'] ?? 0),
                _buildQuadrantCell('Bas-Gauche', quadrants['Bas-Gauche'] ?? 0),
                _buildQuadrantCell('Bas-Droite', quadrants['Bas-Droite'] ?? 0),
              ],
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildQuadrantCell(String label, int count) {
    final percentage = (count / _statistics!.totalShots * 100);
    final intensity = count / _statistics!.totalShots;

    return Container(
      decoration: BoxDecoration(
        color: Color.lerp(
          const Color(0xFF2A2A2A),
          const Color(0xFF1A73E8),
          intensity,
        )!.withOpacity(0.8),
        borderRadius: BorderRadius.circular(8),
      ),
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Text(
            '$count',
            style: const TextStyle(
              color: Colors.white,
              fontSize: 20,
              fontWeight: FontWeight.bold,
            ),
          ),
          Text(
            '${percentage.toStringAsFixed(0)}%',
            style: const TextStyle(color: Colors.white70, fontSize: 12),
          ),
          Text(
            label,
            style: const TextStyle(color: Colors.white54, fontSize: 10),
          ),
        ],
      ),
    );
  }

  Widget _buildBiasWarning() {
    final regional = _statistics!.regional;
    String description = '';
    if (regional.biasX.abs() > 0.05) {
      description += regional.biasX > 0 ? 'vers la droite' : 'vers la gauche';
    }
    if (regional.biasY.abs() > 0.05) {
      if (description.isNotEmpty) description += ' et ';
      description += regional.biasY > 0 ? 'vers le bas' : 'vers le haut';
    }

    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: Colors.orange.withOpacity(0.1),
        borderRadius: BorderRadius.circular(12),
        border: Border.all(color: Colors.orange.withOpacity(0.3)),
      ),
      child: Row(
        children: [
          const Icon(Icons.warning_amber_rounded, color: Colors.orange),
          const SizedBox(width: 12),
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                const Text(
                  'Biais détecté',
                  style: TextStyle(
                    color: Colors.orange,
                    fontWeight: FontWeight.bold,
                  ),
                ),
                Text(
                  'Tendance $description',
                  style: const TextStyle(color: Colors.white70, fontSize: 13),
                ),
              ],
            ),
          ),
        ],
      ),
    );
  }
}