import 'dart:io';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:image/image.dart' as img;
import '../../config/app_config.dart';
import '../documents/pending_documents_provider.dart';
import 'blur_detector.dart';

class DottedVerticalLine extends StatelessWidget {
  final double height;
  final Color color;

  const DottedVerticalLine({super.key, required this.height, this.color = Colors.black45});

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: List.generate((height / 4).floor(), (index) => Container(
        width: 1.5,
        height: 2,
        color: color,
      )),
    );
  }
}

class BlurScoreBar extends StatelessWidget {
  final double score;
  final double threshold = 80.0;
  final double maxScore = 100.0;

  const BlurScoreBar({super.key, required this.score});

  @override
  Widget build(BuildContext context) {
    final double displayScore = score;
    const double displayThreshold = 80.0;
    const double maxDisplayScore = 100.0;

    final double normalizedScore = displayScore / maxDisplayScore;
    final double thresholdRatio = displayThreshold / maxDisplayScore;
    final bool isSharp = displayScore >= displayThreshold;
    final Color barColor = isSharp ? AppConfig.successColor : AppConfig.errorColor;

    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            Text('Ketajaman Foto', style: AppConfig.bodyMedium.copyWith(fontWeight: FontWeight.bold)),
            Text(
              '${displayScore.toStringAsFixed(1)} / ${maxDisplayScore.toInt()}',
              style: AppConfig.bodyMedium.copyWith(color: barColor, fontWeight: FontWeight.bold),
            ),
          ],
        ),
        const SizedBox(height: 8),
        LayoutBuilder(
          builder: (context, constraints) {
            final double totalWidth = constraints.maxWidth;
            final double thresholdPosition = totalWidth * thresholdRatio;

            return Stack(
              clipBehavior: Clip.none,
              children: [
                // 1. Progress Bar Track
                Container(
                  height: 20,
                  width: double.infinity,
                  decoration: BoxDecoration(
                    color: Colors.grey.shade200,
                    borderRadius: BorderRadius.circular(10),
                  ),
                ),
                // 2. Active Filled Bar
                FractionallySizedBox(
                  widthFactor: normalizedScore,
                  child: Container(
                    height: 20,
                    decoration: BoxDecoration(
                      color: barColor,
                      borderRadius: BorderRadius.circular(10),
                    ),
                  ),
                ),
                // 3. Vertical Dotted Threshold Line
                Positioned(
                  left: thresholdPosition,
                  top: 0,
                  bottom: 0,
                  child: const DottedVerticalLine(height: 20, color: Colors.black45),
                ),
                // 4. Threshold Label
                Positioned(
                  left: thresholdPosition - 40,
                  top: 22,
                  child: Text(
                    'Batas Min (${displayThreshold.toInt()})',
                    style: AppConfig.bodySmall.copyWith(
                      color: Colors.grey.shade600,
                      fontWeight: FontWeight.bold,
                      fontSize: 9,
                    ),
                  ),
                ),
              ],
            );
          },
        ),
        const SizedBox(height: 20),
      ],
    );
  }
}

class ImagePreviewScreen extends ConsumerStatefulWidget {
  final String imagePath;
  final double? latitude;
  final double? longitude;

  const ImagePreviewScreen({
    super.key, 
    required this.imagePath,
    this.latitude,
    this.longitude,
  });

  @override
  ConsumerState<ImagePreviewScreen> createState() => _ImagePreviewScreenState();
}

class _ImagePreviewScreenState extends ConsumerState<ImagePreviewScreen> {
  bool _analyzing = true;
  BlurResult? _blurResult;
  late String _currentImagePath;

  @override
  void initState() {
    super.initState();
    _currentImagePath = widget.imagePath;
    _detectBlur();
  }

  Future<void> _detectBlur() async {
    try {
      final result = await BlurDetector.checkBlur(_currentImagePath);
      if (mounted) {
        setState(() {
          _blurResult = result;
          _analyzing = false;
        });
      }
    } catch (e) {
      if (mounted) {
        setState(() {
          _analyzing = false;
        });
      }
    }
  }

  Future<void> _rotateImage() async {
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (context) => const Center(
        child: CircularProgressIndicator(color: AppConfig.primaryColor),
      ),
    );

    try {
      final bytes = await File(_currentImagePath).readAsBytes();
      final decoded = img.decodeImage(bytes);
      if (decoded != null) {
        // Rotate 90 degrees clockwise
        final rotated = img.copyRotate(decoded, angle: 90);
        final encoded = img.encodeJpg(rotated);

        final dir = Directory(_currentImagePath).parent.path;
        final name = _currentImagePath.split('/').last.split('\\').last;
        final newPath = '$dir/rotated_${DateTime.now().millisecondsSinceEpoch}_$name';

        await File(newPath).writeAsBytes(encoded);

        // Delete old rotated files to prevent memory leaks/leftovers
        if (_currentImagePath.contains('rotated_')) {
          try {
            await File(_currentImagePath).delete();
          } catch (_) {}
        }

        if (mounted) {
          setState(() {
            _currentImagePath = newPath;
            _analyzing = true;
          });
          Navigator.pop(context); // Close loading dialog
          _detectBlur(); // Re-run blur analysis
        }
      } else {
        if (mounted) Navigator.pop(context);
      }
    } catch (e) {
      if (mounted) Navigator.pop(context);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: AppConfig.backgroundColor,
      appBar: AppBar(
        title: const Text('Konfirmasi Foto'),
        actions: [
          IconButton(
            icon: const Icon(Icons.rotate_right),
            onPressed: _rotateImage,
            tooltip: 'Putar 90°',
          ),
        ],
      ),
      body: SafeArea(
        child: Column(
          children: [
            // Interactive photo view (with pinch-to-zoom support)
            Expanded(
              child: Stack(
                children: [
                  Container(
                    margin: const EdgeInsets.all(16),
                    decoration: BoxDecoration(
                      color: Colors.white,
                      borderRadius: BorderRadius.circular(16),
                      boxShadow: [
                        BoxShadow(
                          color: Colors.black.withOpacity(0.05),
                          blurRadius: 10,
                          spreadRadius: 2,
                        )
                      ],
                      border: Border.all(color: Colors.grey.shade200),
                    ),
                    child: ClipRRect(
                      borderRadius: BorderRadius.circular(16),
                      child: InteractiveViewer(
                        maxScale: 4.0,
                        child: Center(
                          child: Hero(
                            tag: 'doc_image_preview',
                            child: Image.file(
                              File(_currentImagePath),
                              fit: BoxFit.contain,
                            ),
                          ),
                        ),
                      ),
                    ),
                  ),
                  Positioned(
                    bottom: 24,
                    right: 24,
                    child: FloatingActionButton.small(
                      heroTag: 'rotate_button',
                      backgroundColor: Colors.white.withOpacity(0.9),
                      foregroundColor: AppConfig.primaryColor,
                      onPressed: _rotateImage,
                      child: const Icon(Icons.rotate_right),
                    ),
                  ),
                ],
              ),
            ),
            
            // Bottom confirmation box
            Container(
              padding: const EdgeInsets.all(24.0),
              decoration: BoxDecoration(
                color: Colors.white,
                borderRadius: const BorderRadius.vertical(top: Radius.circular(24)),
                boxShadow: [
                  BoxShadow(
                    color: Colors.black.withOpacity(0.05),
                    blurRadius: 15,
                    offset: const Offset(0, -5),
                  )
                ],
              ),
              child: Column(
                mainAxisSize: MainAxisSize.min,
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
                  Text(
                    'Periksa Kualitas Foto',
                    style: AppConfig.h2.copyWith(fontWeight: FontWeight.bold),
                    textAlign: TextAlign.center,
                  ),
                  const SizedBox(height: 16),
                  
                  // Blur status area
                  if (_analyzing)
                    Row(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        const SizedBox(
                          width: 20,
                          height: 20,
                          child: CircularProgressIndicator(strokeWidth: 2, color: AppConfig.primaryColor),
                        ),
                        const SizedBox(width: 12),
                        Text(
                          'Menganalisis ketajaman foto...',
                          style: AppConfig.bodyMedium.copyWith(color: AppConfig.textSecondary),
                        ),
                      ],
                    )
                  else if (_blurResult != null) ...[
                    BlurScoreBar(score: _blurResult!.score),
                    _buildBlurBadge(_blurResult!)
                  ] else
                    Text(
                      'Pastikan seluruh area dokumen masuk ke dalam frame, tulisan dapat terbaca dengan jelas, dan hasil foto tidak blur.',
                      style: AppConfig.bodyMedium.copyWith(color: AppConfig.textSecondary),
                      textAlign: TextAlign.center,
                    ),

                  const SizedBox(height: 24),
                  Row(
                    children: [
                      // Retake Button
                      Expanded(
                        child: OutlinedButton(
                          onPressed: () => Navigator.pop(context),
                          style: OutlinedButton.styleFrom(
                            foregroundColor: AppConfig.textPrimary,
                            side: BorderSide(color: Colors.grey.shade400),
                            shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
                            padding: const EdgeInsets.symmetric(vertical: 14),
                          ),
                          child: const Text('Ambil Ulang', style: TextStyle(fontWeight: FontWeight.bold)),
                        ),
                      ),
                      const SizedBox(width: 16),
                      // Confirm & Sync Button
                      Expanded(
                        child: ElevatedButton(
                          onPressed: (!_analyzing && _blurResult != null && !_blurResult!.isBlur) ? () {
                            ref.read(pendingDocumentsProvider.notifier).addDocument(
                              _currentImagePath,
                              latitude: widget.latitude,
                              longitude: widget.longitude,
                            );
                            Navigator.pop(context);
                            context.go('/documents');
                          } : null,
                          style: ElevatedButton.styleFrom(
                            backgroundColor: AppConfig.primaryColor,
                            foregroundColor: Colors.white,
                            shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
                            padding: const EdgeInsets.symmetric(vertical: 14),
                          ),
                          child: const Text('Unggah Dokumen', style: TextStyle(fontWeight: FontWeight.bold)),
                        ),
                      ),
                    ],
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildBlurBadge(BlurResult result) {
    if (result.isBlur) {
      return Container(
        padding: const EdgeInsets.all(12),
        decoration: BoxDecoration(
          color: AppConfig.errorColor.withOpacity(0.1),
          borderRadius: BorderRadius.circular(12),
          border: Border.all(color: AppConfig.errorColor.withOpacity(0.3)),
        ),
        child: Row(
          children: [
            const Icon(Icons.warning_amber_rounded, color: AppConfig.errorColor, size: 24),
            const SizedBox(width: 12),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text(
                    'Foto Terdeteksi Blur!',
                    style: AppConfig.bodyMedium.copyWith(color: AppConfig.errorColor, fontWeight: FontWeight.bold),
                  ),
                  const SizedBox(height: 2),
                  Text(
                    'Diharuskan untuk mengambil ulang gambar.',
                    style: AppConfig.bodySmall.copyWith(color: AppConfig.textSecondary),
                  ),
                ],
              ),
            ),
          ],
        ),
      );
    } else {
      return Container(
        padding: const EdgeInsets.all(12),
        decoration: BoxDecoration(
          color: AppConfig.successColor.withOpacity(0.1),
          borderRadius: BorderRadius.circular(12),
          border: Border.all(color: AppConfig.successColor.withOpacity(0.3)),
        ),
        child: Row(
          children: [
            const Icon(Icons.check_circle_outline, color: AppConfig.successColor, size: 24),
            const SizedBox(width: 12),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text(
                    'Kualitas Foto Baik',
                    style: AppConfig.bodyMedium.copyWith(color: AppConfig.successColor, fontWeight: FontWeight.bold),
                  ),
                  const SizedBox(height: 2),
                  Text(
                    'Fokus dan ketajaman gambar optimal.',
                    style: AppConfig.bodySmall.copyWith(color: AppConfig.textSecondary),
                  ),
                ],
              ),
            ),
          ],
        ),
      );
    }
  }
}