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/session.dart';
import '../../data/models/target_type.dart';
import '../../data/repositories/session_repository.dart';
import 'session_detail_screen.dart';
import 'widgets/session_list_item.dart';
import 'widgets/history_chart.dart';

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

  @override
  State<HistoryScreen> createState() => _HistoryScreenState();
}

class _HistoryScreenState extends State<HistoryScreen> {
  List<Session> _sessions = [];
  bool _isLoading = true;
  TargetType? _filterType;

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

  Future<void> _loadSessions() async {
    setState(() => _isLoading = true);

    try {
      final repository = context.read<SessionRepository>();
      final sessions = await repository.getAllSessions(
        targetType: _filterType,
      );

      if (mounted) {
        setState(() {
          _sessions = sessions;
          _isLoading = false;
        });
      }
    } catch (e) {
      if (mounted) {
        setState(() => _isLoading = false);
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('Erreur de chargement: $e'),
            backgroundColor: AppTheme.errorColor,
          ),
        );
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Historique'),
        actions: [
          PopupMenuButton<TargetType?>(
            icon: const Icon(Icons.filter_list),
            tooltip: 'Filtrer',
            onSelected: (type) {
              setState(() => _filterType = type);
              _loadSessions();
            },
            itemBuilder: (context) => [
              const PopupMenuItem(
                value: null,
                child: Text('Tous'),
              ),
              ...TargetType.values.map((type) => PopupMenuItem(
                value: type,
                child: Text(type.displayName),
              )),
            ],
          ),
        ],
      ),
      body: _isLoading
          ? const Center(child: CircularProgressIndicator())
          : _sessions.isEmpty
              ? _buildEmptyState()
              : _buildContent(),
    );
  }

  Widget _buildEmptyState() {
    return Center(
      child: Padding(
        padding: const EdgeInsets.all(AppConstants.defaultPadding),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Icon(Icons.history, size: 64, color: Colors.grey[400]),
            const SizedBox(height: 16),
            Text(
              'Aucune session',
              style: Theme.of(context).textTheme.titleLarge,
            ),
            const SizedBox(height: 8),
            Text(
              _filterType != null
                  ? 'Aucune session de type ${_filterType!.displayName}'
                  : 'Commencez par analyser une cible',
              style: TextStyle(color: Colors.grey[600]),
              textAlign: TextAlign.center,
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildContent() {
    return RefreshIndicator(
      onRefresh: _loadSessions,
      child: CustomScrollView(
        slivers: [
          // Chart section
          if (_sessions.length >= 2)
            SliverToBoxAdapter(
              child: Padding(
                padding: const EdgeInsets.all(AppConstants.defaultPadding),
                child: HistoryChart(sessions: _sessions),
              ),
            ),

          // Filter indicator
          if (_filterType != null)
            SliverToBoxAdapter(
              child: Padding(
                padding: const EdgeInsets.symmetric(horizontal: AppConstants.defaultPadding),
                child: Chip(
                  label: Text('Filtre: ${_filterType!.displayName}'),
                  deleteIcon: const Icon(Icons.close, size: 18),
                  onDeleted: () {
                    setState(() => _filterType = null);
                    _loadSessions();
                  },
                ),
              ),
            ),

          // Sessions list
          SliverPadding(
            padding: const EdgeInsets.all(AppConstants.defaultPadding),
            sliver: SliverList(
              delegate: SliverChildBuilderDelegate(
                (context, index) {
                  final session = _sessions[index];
                  return Padding(
                    padding: const EdgeInsets.only(bottom: 12),
                    child: SessionListItem(
                      session: session,
                      onTap: () => _openSessionDetail(session),
                      onDelete: () => _deleteSession(session),
                    ),
                  );
                },
                childCount: _sessions.length,
              ),
            ),
          ),
        ],
      ),
    );
  }

  void _openSessionDetail(Session session) async {
    await Navigator.push(
      context,
      MaterialPageRoute(
        builder: (_) => SessionDetailScreen(session: session),
      ),
    );
    _loadSessions(); // Refresh in case session was deleted
  }

  Future<void> _deleteSession(Session session) async {
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('Supprimer'),
        content: Text(
          'Supprimer la session du ${DateFormat('dd/MM/yyyy').format(session.createdAt)}?',
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context, false),
            child: const Text('Annuler'),
          ),
          TextButton(
            onPressed: () => Navigator.pop(context, true),
            child: const Text('Supprimer', style: TextStyle(color: AppTheme.errorColor)),
          ),
        ],
      ),
    );

    if (confirmed == true && mounted) {
      try {
        final repository = context.read<SessionRepository>();
        await repository.deleteSession(session.id);
        _loadSessions();
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(content: Text('Session supprimee')),
          );
        }
      } catch (e) {
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              content: Text('Erreur: $e'),
              backgroundColor: AppTheme.errorColor,
            ),
          );
        }
      }
    }
  }
}