import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:intl/intl.dart';
import '../../core/constants/app_constants.dart';
import '../../core/theme/app_theme.dart';
import '../../data/models/weapon.dart';
import '../../data/repositories/session_repository.dart';
import 'session_provider.dart';
import '../capture/capture_screen.dart';
import '../garage/weapon_list_screen.dart';

class SessionSetupScreen extends StatefulWidget {
  const SessionSetupScreen({super.key});

  @override
  State<SessionSetupScreen> createState() => _SessionSetupScreenState();
}

class _SessionSetupScreenState extends State<SessionSetupScreen> {
  final _formKey = GlobalKey<FormState>();

  int _shotsPerTarget = 5;
  int _distance = 25;
  List<Weapon> _availableWeapons = [];
  Weapon? _selectedWeapon;
  bool _isLoadingWeapons = true;

  DateTime _selectedDate = DateTime.now();

  static const List<int> _presetDistances = [10, 15, 25, 50, 100, 200];
  static const List<int> _presetShots = [3, 5, 10, 15, 20, 30];

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

  Future<void> _loadWeapons() async {
    setState(() => _isLoadingWeapons = true);
    final repository = context.read<SessionRepository>();
    final weapons = await repository.getWeapons();

    if (mounted) {
      setState(() {
        _availableWeapons = weapons;
        if (_availableWeapons.isNotEmpty && _selectedWeapon == null) {
          _selectedWeapon = _availableWeapons.first;
          _updateSettingsForWeapon(_selectedWeapon!);
        }
        _isLoadingWeapons = false;
      });
    }
  }

  void _updateSettingsForWeapon(Weapon weapon) {
    _shotsPerTarget = weapon.magazineCapacity > 0 ? weapon.magazineCapacity : 5;
    _distance = (weapon.type == WeaponType.handgun) ? 25 : 50;
  }

  Future<void> _pickDate() async {
    final DateTime? picked = await showDatePicker(
      context: context,
      initialDate: _selectedDate,
      firstDate: DateTime(2020),
      lastDate: DateTime(2100),
      locale: const Locale('fr', 'FR'),
    );
    if (picked != null && picked != _selectedDate) {
      setState(() {
        final now = DateTime.now();
        _selectedDate = DateTime(
          picked.year,
          picked.month,
          picked.day,
          now.hour,
          now.minute,
        );
      });
    }
  }

  void _startSession() {
    if (_formKey.currentState!.validate() && _selectedWeapon != null) {
      final repository = context.read<SessionRepository>();
      final sessionProvider = context.read<SessionProvider>();

      final sessionId = repository.generateId();

      sessionProvider.startSession(
        _selectedWeapon!.displayName,
        _shotsPerTarget,
        sessionId,
        weaponId: _selectedWeapon!.id,
        distance: _distance,
        date: _selectedDate,
      );

      Navigator.pushReplacement(
        context,
        MaterialPageRoute(builder: (_) => const CaptureScreen()),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final isDark = Theme.of(context).brightness == Brightness.dark;
    final formattedDate = DateFormat('dd MMMM yyyy • HH:mm', 'fr_FR').format(_selectedDate);

    return Scaffold(
      appBar: AppBar(
        title: const Text('Configuration de Session'),
      ),
      body: _isLoadingWeapons
          ? const Center(child: CircularProgressIndicator())
          : SingleChildScrollView(
              padding: const EdgeInsets.all(AppConstants.defaultPadding),
              child: Form(
                key: _formKey,
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.stretch,
                  children: [
                    if (_availableWeapons.isEmpty)
                      _buildEmptyArmoryState(isDark)
                    else ...[
                      _buildWeaponAndDateSection(isDark, formattedDate),
                      const SizedBox(height: 20),
                      _buildDistanceSection(isDark),
                      const SizedBox(height: 20),
                      _buildShotsSection(isDark),
                      const SizedBox(height: 32),
                      _buildStartButton(),
                      const SizedBox(height: 16),
                    ],
                  ],
                ),
              ),
            ),
    );
  }

  Widget _buildEmptyArmoryState(bool isDark) {
    return Container(
      padding: const EdgeInsets.all(24),
      decoration: BoxDecoration(
        color: isDark ? AppTheme.darkSurface : AppTheme.lightSurface,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(
          color: AppTheme.errorColor.withValues(alpha: 0.5),
        ),
      ),
      child: Column(
        children: [
          const Icon(
            Icons.warning_amber_rounded,
            color: AppTheme.errorColor,
            size: 52,
          ),
          const SizedBox(height: 12),
          Text(
            'Armurerie vide',
            style: TextStyle(
              fontSize: 18,
              fontWeight: FontWeight.w700,
              color: isDark ? AppTheme.darkTextPrimary : AppTheme.lightTextPrimary,
            ),
          ),
          const SizedBox(height: 6),
          Text(
            'Ajoutez au moins une arme dans votre armurerie pour débuter une séance.',
            textAlign: TextAlign.center,
            style: TextStyle(
              fontSize: 13,
              color: isDark ? AppTheme.darkTextSecondary : AppTheme.lightTextSecondary,
            ),
          ),
          const SizedBox(height: 20),
          ElevatedButton.icon(
            onPressed: () {
              Navigator.push(
                context,
                MaterialPageRoute(builder: (_) => const WeaponListScreen()),
              ).then((_) => _loadWeapons());
            },
            icon: const Icon(Icons.shield),
            label: const Text('Aller à l\'armurerie'),
          ),
        ],
      ),
    );
  }

  Widget _buildWeaponAndDateSection(bool isDark, String formattedDate) {
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                const Icon(Icons.tune, color: AppTheme.primaryColor, size: 20),
                const SizedBox(width: 8),
                Text(
                  'Arme & Date',
                  style: TextStyle(
                    fontSize: 15,
                    fontWeight: FontWeight.w700,
                    color: isDark ? AppTheme.darkTextPrimary : AppTheme.lightTextPrimary,
                  ),
                ),
              ],
            ),
            const SizedBox(height: 16),
            DropdownButtonFormField<Weapon>(
              initialValue: _selectedWeapon,
              decoration: const InputDecoration(
                labelText: 'Arme utilisée',
                prefixIcon: Icon(Icons.shield_outlined),
              ),
              items: _availableWeapons
                  .map(
                    (w) => DropdownMenuItem(
                      value: w,
                      child: Text('${w.displayName} (${w.caliber})'),
                    ),
                  )
                  .toList(),
              onChanged: (value) {
                if (value != null) {
                  setState(() {
                    _selectedWeapon = value;
                    _updateSettingsForWeapon(value);
                  });
                }
              },
            ),
            const SizedBox(height: 12),
            InkWell(
              onTap: _pickDate,
              borderRadius: BorderRadius.circular(12),
              child: IgnorePointer(
                child: TextFormField(
                  decoration: const InputDecoration(
                    labelText: 'Date de séance',
                    prefixIcon: Icon(Icons.calendar_today_outlined),
                  ),
                  controller: TextEditingController(text: formattedDate),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildDistanceSection(bool isDark) {
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Row(
                  children: [
                    const Icon(Icons.straighten, color: AppTheme.secondaryColor, size: 20),
                    const SizedBox(width: 8),
                    Text(
                      'Distance de Tir',
                      style: TextStyle(
                        fontSize: 15,
                        fontWeight: FontWeight.w700,
                        color: isDark ? AppTheme.darkTextPrimary : AppTheme.lightTextPrimary,
                      ),
                    ),
                  ],
                ),
                Container(
                  padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
                  decoration: BoxDecoration(
                    color: AppTheme.secondaryColor.withValues(alpha: isDark ? 0.2 : 0.1),
                    borderRadius: BorderRadius.circular(8),
                    border: Border.all(
                      color: AppTheme.secondaryColor.withValues(alpha: 0.4),
                    ),
                  ),
                  child: Text(
                    '${_distance}m',
                    style: const TextStyle(
                      fontSize: 16,
                      fontWeight: FontWeight.w800,
                      color: AppTheme.secondaryColor,
                    ),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 12),
            Wrap(
              spacing: 8,
              runSpacing: 8,
              children: _presetDistances.map((d) {
                final isSelected = _distance == d;
                return ChoiceChip(
                  label: Text('${d}m'),
                  selected: isSelected,
                  onSelected: (selected) {
                    if (selected) setState(() => _distance = d);
                  },
                );
              }).toList(),
            ),
            const SizedBox(height: 8),
            Slider(
              value: _distance.toDouble(),
              min: 5,
              max: 300,
              divisions: 59,
              activeColor: AppTheme.secondaryColor,
              onChanged: (val) {
                setState(() => _distance = val.round());
              },
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildShotsSection(bool isDark) {
    final primaryColor = Theme.of(context).colorScheme.primary;
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Row(
                  children: [
                    Icon(Icons.ads_click, color: primaryColor, size: 20),
                    const SizedBox(width: 8),
                    Text(
                      'Tirs par Cible',
                      style: TextStyle(
                        fontSize: 15,
                        fontWeight: FontWeight.w700,
                        color: isDark ? AppTheme.darkTextPrimary : AppTheme.lightTextPrimary,
                      ),
                    ),
                  ],
                ),
                Container(
                  padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
                  decoration: BoxDecoration(
                    color: primaryColor.withValues(alpha: isDark ? 0.2 : 0.1),
                    borderRadius: BorderRadius.circular(8),
                    border: Border.all(
                      color: primaryColor.withValues(alpha: 0.4),
                    ),
                  ),
                  child: Text(
                    '$_shotsPerTarget tirs',
                    style: TextStyle(
                      fontSize: 16,
                      fontWeight: FontWeight.w800,
                      color: primaryColor,
                    ),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 12),
            Wrap(
              spacing: 8,
              runSpacing: 8,
              children: _presetShots.map((s) {
                final isSelected = _shotsPerTarget == s;
                return ChoiceChip(
                  label: Text('$s coups'),
                  selected: isSelected,
                  onSelected: (selected) {
                    if (selected) setState(() => _shotsPerTarget = s);
                  },
                );
              }).toList(),
            ),
            const SizedBox(height: 8),
            Slider(
              value: _shotsPerTarget.toDouble(),
              min: 1,
              max: 50,
              divisions: 49,
              activeColor: primaryColor,
              onChanged: (val) {
                setState(() => _shotsPerTarget = val.round());
              },
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildStartButton() {
    final primaryColor = Theme.of(context).colorScheme.primary;
    return Container(
      decoration: BoxDecoration(
        borderRadius: BorderRadius.circular(16),
        gradient: LinearGradient(
          colors: [
            primaryColor,
            HSLColor.fromColor(primaryColor).withLightness((HSLColor.fromColor(primaryColor).lightness + 0.15).clamp(0.0, 1.0)).toColor(),
          ],
          begin: Alignment.topLeft,
          end: Alignment.bottomRight,
        ),
        boxShadow: [
          BoxShadow(
            color: primaryColor.withValues(alpha: 0.35),
            blurRadius: 16,
            offset: const Offset(0, 4),
          ),
        ],
      ),
      child: ElevatedButton.icon(
        onPressed: (_availableWeapons.isEmpty || _selectedWeapon == null)
            ? null
            : _startSession,
        style: ElevatedButton.styleFrom(
          backgroundColor: Colors.transparent,
          foregroundColor: Colors.white,
          shadowColor: Colors.transparent,
          padding: const EdgeInsets.symmetric(vertical: 18),
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(16),
          ),
        ),
        icon: const Icon(Icons.play_arrow_rounded, size: 26),
        label: const Text(
          'DÉMARRER LA SESSION',
          style: TextStyle(
            fontSize: 16,
            fontWeight: FontWeight.w800,
            letterSpacing: 0.8,
          ),
        ),
      ),
    );
  }
}