/// Écran de capture - Première étape du workflow d'analyse.
///
/// Permet de sélectionner le type de cible (concentrique ou silhouette)
/// et la source d'image (caméra ou galerie). Affiche un aperçu de l'image
/// sélectionnée avant de lancer l'analyse.
library;

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import '../../core/constants/app_constants.dart';
import '../../core/theme/app_theme.dart';
import '../../data/models/target_type.dart';
import '../analysis/analysis_screen.dart';
import 'widgets/target_type_selector.dart';
import 'widgets/image_source_button.dart';

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

  @override
  State<CaptureScreen> createState() => _CaptureScreenState();
}

class _CaptureScreenState extends State<CaptureScreen> {
  final ImagePicker _picker = ImagePicker();
  TargetType _selectedType = TargetType.concentric;
  String? _selectedImagePath;
  bool _isLoading = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Nouvelle Analyse'),
      ),
      body: SingleChildScrollView(
        padding: const EdgeInsets.all(AppConstants.defaultPadding),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            // Target type selection
            _buildSectionTitle('Type de Cible'),
            const SizedBox(height: 12),
            TargetTypeSelector(
              selectedType: _selectedType,
              onTypeSelected: (type) {
                setState(() => _selectedType = type);
              },
            ),
            const SizedBox(height: AppConstants.largePadding),

            // Image source selection
            _buildSectionTitle('Source de l\'Image'),
            const SizedBox(height: 12),
            Row(
              children: [
                Expanded(
                  child: ImageSourceButton(
                    icon: Icons.camera_alt,
                    label: 'Camera',
                    onPressed: _isLoading ? null : () => _captureImage(ImageSource.camera),
                  ),
                ),
                const SizedBox(width: 12),
                Expanded(
                  child: ImageSourceButton(
                    icon: Icons.photo_library,
                    label: 'Galerie',
                    onPressed: _isLoading ? null : () => _captureImage(ImageSource.gallery),
                  ),
                ),
              ],
            ),
            const SizedBox(height: AppConstants.largePadding),

            // Image preview
            if (_isLoading)
              const Center(
                child: Padding(
                  padding: EdgeInsets.all(32),
                  child: CircularProgressIndicator(),
                ),
              )
            else if (_selectedImagePath != null)
              _buildImagePreview(),

            // Guide text
            if (_selectedImagePath == null && !_isLoading)
              _buildGuide(),
          ],
        ),
      ),
      floatingActionButton: _selectedImagePath != null
          ? FloatingActionButton.extended(
              onPressed: _analyzeImage,
              icon: const Icon(Icons.analytics),
              label: const Text('Analyser'),
            )
          : null,
    );
  }

  Widget _buildSectionTitle(String title) {
    return Text(
      title,
      style: Theme.of(context).textTheme.titleMedium?.copyWith(
        fontWeight: FontWeight.bold,
      ),
    );
  }

  Widget _buildImagePreview() {
    return Column(
      children: [
        _buildSectionTitle('Apercu'),
        const SizedBox(height: 12),
        ClipRRect(
          borderRadius: BorderRadius.circular(AppConstants.borderRadius),
          child: Stack(
            children: [
              Image.file(
                File(_selectedImagePath!),
                fit: BoxFit.contain,
                width: double.infinity,
              ),
              Positioned(
                top: 8,
                right: 8,
                child: IconButton(
                  icon: const Icon(Icons.close),
                  onPressed: () {
                    setState(() => _selectedImagePath = null);
                  },
                  style: IconButton.styleFrom(
                    backgroundColor: Colors.black54,
                    foregroundColor: Colors.white,
                  ),
                ),
              ),
            ],
          ),
        ),
        const SizedBox(height: 12),
        _buildFramingHints(),
      ],
    );
  }

  Widget _buildFramingHints() {
    return Card(
      color: AppTheme.warningColor.withValues(alpha: 0.1),
      child: Padding(
        padding: const EdgeInsets.all(12),
        child: Row(
          children: [
            Icon(Icons.info_outline, color: AppTheme.warningColor),
            const SizedBox(width: 12),
            Expanded(
              child: Text(
                'Assurez-vous que la cible est bien centree et visible.',
                style: TextStyle(color: AppTheme.warningColor.withValues(alpha: 0.8)),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildGuide() {
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(AppConstants.defaultPadding),
        child: Column(
          children: [
            Icon(
              Icons.help_outline,
              size: 48,
              color: Colors.grey[400],
            ),
            const SizedBox(height: 12),
            Text(
              'Conseils pour une bonne analyse',
              style: Theme.of(context).textTheme.titleSmall?.copyWith(
                fontWeight: FontWeight.bold,
              ),
            ),
            const SizedBox(height: 12),
            _buildGuideItem(Icons.crop_free, 'Cadrez la cible entiere dans l\'image'),
            _buildGuideItem(Icons.wb_sunny, 'Utilisez un bon eclairage'),
            _buildGuideItem(Icons.straighten, 'Prenez la photo de face'),
            _buildGuideItem(Icons.blur_off, 'Evitez les images floues'),
          ],
        ),
      ),
    );
  }

  Widget _buildGuideItem(IconData icon, String text) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 4),
      child: Row(
        children: [
          Icon(icon, size: 20, color: AppTheme.primaryColor),
          const SizedBox(width: 12),
          Expanded(child: Text(text)),
        ],
      ),
    );
  }

  Future<void> _captureImage(ImageSource source) async {
    setState(() => _isLoading = true);

    try {
      final XFile? image = await _picker.pickImage(
        source: source,
        maxWidth: 2048,
        maxHeight: 2048,
        imageQuality: 90,
      );

      if (image != null) {
        setState(() => _selectedImagePath = image.path);
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('Erreur lors de la capture: $e'),
            backgroundColor: AppTheme.errorColor,
          ),
        );
      }
    } finally {
      if (mounted) {
        setState(() => _isLoading = false);
      }
    }
  }

  void _analyzeImage() {
    if (_selectedImagePath == null) return;

    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (_) => AnalysisScreen(
          imagePath: _selectedImagePath!,
          targetType: _selectedType,
        ),
      ),
    );
  }
}