import 'dart:io';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/material.dart';
import 'package:flutter_cache_manager/flutter_cache_manager.dart';
import 'package:flutter_lucide/flutter_lucide.dart';
import 'package:gal/gal.dart';
import 'package:http/http.dart' as http;
import 'package:image_picker/image_picker.dart';
import 'package:path_provider/path_provider.dart';
import 'package:video_player/video_player.dart';

import '../../core/api/services/feedback_api.dart';
import '../../core/theme/app_colors.dart';
import '../../core/theme/app_spacing.dart';
import '../../core/theme/app_typography.dart';
import '../../features/gallery/models/gallery_task_item.dart';
import '../../shared/widgets/top_nav_bar.dart';

/// Video Generation Result screen - matches Pencil cFA4T
class GenerationResultScreen extends StatefulWidget {
  const GenerationResultScreen({super.key, this.mediaItem});

  final GalleryMediaItem? mediaItem;

  @override
  State<GenerationResultScreen> createState() => _GenerationResultScreenState();
}

class _GenerationResultScreenState extends State<GenerationResultScreen> {
  VideoPlayerController? _videoController;
  bool _saving = false;
  bool _videoLoading = true;
  String? _videoLoadError;

  String? get _videoUrl => widget.mediaItem?.videoUrl;
  String? get _imageUrl => widget.mediaItem?.imageUrl;

  @override
  void initState() {
    super.initState();
    if (_videoUrl != null) {
      _initVideoFromCache();
    }
  }

  Future<void> _initVideoFromCache() async {
    if (_videoUrl == null) return;
    try {
      final file = await DefaultCacheManager().getSingleFile(_videoUrl!);
      if (!mounted) return;
      final controller = VideoPlayerController.file(file);
      await controller.initialize();
      if (!mounted) return;
      setState(() {
        _videoController = controller;
        _videoLoading = false;
      });
    } catch (e) {
      if (mounted) {
        setState(() {
          _videoLoading = false;
          _videoLoadError = e.toString();
        });
      }
    }
  }

  @override
  void dispose() {
    _videoController?.dispose();
    super.dispose();
  }

  Future<void> _saveToAlbum() async {
    if (widget.mediaItem == null) return;
    setState(() => _saving = true);

    try {
      final hasAccess = await Gal.hasAccess(toAlbum: true);
      if (!hasAccess) {
        final granted = await Gal.requestAccess(toAlbum: true);
        if (!granted) {
          throw Exception('Photo library access denied');
        }
      }

      if (_videoUrl != null) {
        final tempDir = await getTemporaryDirectory();
        final file = File(
            '${tempDir.path}/gallery_video_${DateTime.now().millisecondsSinceEpoch}.mp4');
        final response = await http.get(Uri.parse(_videoUrl!));
        if (response.statusCode != 200) {
          throw Exception('Failed to download video');
        }
        await file.writeAsBytes(response.bodyBytes);
        await Gal.putVideo(file.path);
        await file.delete();
      } else if (_imageUrl != null) {
        final tempDir = await getTemporaryDirectory();
        final file = File(
            '${tempDir.path}/gallery_image_${DateTime.now().millisecondsSinceEpoch}.jpg');
        final response = await http.get(Uri.parse(_imageUrl!));
        if (response.statusCode != 200) {
          throw Exception('Failed to download image');
        }
        await file.writeAsBytes(response.bodyBytes);
        await Gal.putImage(file.path);
        await file.delete();
      }

      if (mounted) {
        setState(() => _saving = false);
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Saved to photo library')),
        );
      }
    } catch (e) {
      if (mounted) {
        setState(() => _saving = false);
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Save failed: $e')),
        );
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: AppColors.background,
      appBar: PreferredSize(
        preferredSize: const Size.fromHeight(56),
        child: TopNavBar(
          title: 'Ready',
          showBackButton: true,
          onBack: () => Navigator.of(context).pop(),
        ),
      ),
      body: widget.mediaItem == null
          ? const Center(
              child: Text(
                'No media',
                style: TextStyle(color: AppColors.textSecondary),
              ),
            )
          : SingleChildScrollView(
              padding: const EdgeInsets.all(AppSpacing.screenPaddingLarge),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
                  _MediaDisplay(
                    videoUrl: _videoUrl,
                    imageUrl: _imageUrl,
                    videoController: _videoController,
                    videoLoading: _videoUrl != null ? _videoLoading : false,
                    videoLoadError: _videoLoadError,
                  ),
                  const SizedBox(height: AppSpacing.xxl),
                  _DownloadButton(
                    onDownload: _saving ? null : _saveToAlbum,
                    saving: _saving,
                  )
                ],
              ),
            ),
    );
  }
}

class _MediaDisplay extends StatelessWidget {
  const _MediaDisplay({
    this.videoUrl,
    this.imageUrl,
    this.videoController,
    this.videoLoading = false,
    this.videoLoadError,
  });

  final String? videoUrl;
  final String? imageUrl;
  final VideoPlayerController? videoController;
  final bool videoLoading;
  final String? videoLoadError;

  @override
  Widget build(BuildContext context) {
    return Container(
      height: 360,
      decoration: BoxDecoration(
        color: AppColors.textPrimary,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: AppColors.border, width: 1),
      ),
      child: ClipRRect(
        borderRadius: BorderRadius.circular(16),
        child: Stack(
          fit: StackFit.expand,
          children: [
            videoUrl != null && videoController != null
                ? _VideoPlayer(
                    controller: videoController!,
                  )
                : videoUrl != null && videoLoading
                    ? Container(
                        color: AppColors.textPrimary,
                        alignment: Alignment.center,
                        child: const CircularProgressIndicator(
                          color: AppColors.surface,
                        ),
                      )
                    : videoUrl != null && videoLoadError != null
                        ? Container(
                            color: AppColors.textPrimary,
                            alignment: Alignment.center,
                            child: const Text(
                              'Load failed',
                              style: TextStyle(color: AppColors.surface),
                            ),
                          )
                        : imageUrl != null
                            ? CachedNetworkImage(
                                imageUrl: imageUrl!,
                                fit: BoxFit.cover,
                                placeholder: (_, __) => _Placeholder(),
                                errorWidget: (_, __, ___) => _Placeholder(),
                              )
                            : _Placeholder(),
            Positioned(
              top: 16,
              right: 20,
              child: GestureDetector(
                onTap: () => _ReportDialog.show(context),
                child: Container(
                  width: 44,
                  height: 44,
                  decoration: BoxDecoration(
                    color: Colors.black.withValues(alpha: 0.6),
                    borderRadius: BorderRadius.circular(8),
                  ),
                  alignment: Alignment.center,
                  child: Icon(
                    LucideIcons.triangle_alert,
                    size: 24,
                    color: AppColors.surface,
                  ),
                ),
              ),
            ),
            Positioned(
              bottom: 20,
              right: 20,
              child: Text(
                'PetsHero AI',
                style: AppTypography.bodyMedium.copyWith(
                  color: AppColors.surface.withValues(alpha: 0.6),
                  fontSize: 12,
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _VideoPlayer extends StatefulWidget {
  const _VideoPlayer({required this.controller});

  final VideoPlayerController controller;

  @override
  State<_VideoPlayer> createState() => _VideoPlayerState();
}

class _VideoPlayerState extends State<_VideoPlayer> {
  @override
  void initState() {
    super.initState();
    widget.controller.addListener(_listener);
  }

  @override
  void dispose() {
    widget.controller.removeListener(_listener);
    super.dispose();
  }

  void _listener() {
    if (mounted) setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    if (!widget.controller.value.isInitialized) {
      return Container(
        color: AppColors.textPrimary,
        child: const Center(
          child: CircularProgressIndicator(color: AppColors.surface),
        ),
      );
    }

    return GestureDetector(
      onTap: () {
        if (widget.controller.value.isPlaying) {
          widget.controller.pause();
        } else {
          widget.controller.play();
        }
      },
      child: FittedBox(
        fit: BoxFit.contain,
        child: SizedBox(
          width: widget.controller.value.size.width > 0
              ? widget.controller.value.size.width
              : 16,
          height: widget.controller.value.size.height > 0
              ? widget.controller.value.size.height
              : 9,
          child: VideoPlayer(widget.controller),
        ),
      ),
    );
  }
}

class _Placeholder extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      color: AppColors.textPrimary,
      alignment: Alignment.center,
      child: Text(
        'Your work is ready',
        style: AppTypography.bodyRegular.copyWith(
          color: AppColors.surface.withValues(alpha: 0.6),
        ),
      ),
    );
  }
}

class _DownloadButton extends StatelessWidget {
  const _DownloadButton({
    required this.onDownload,
    this.saving = false,
  });

  final VoidCallback? onDownload;
  final bool saving;

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: onDownload,
      child: Container(
        height: 52,
        decoration: BoxDecoration(
          color: saving ? AppColors.surfaceAlt : AppColors.primary,
          borderRadius: BorderRadius.circular(14),
          boxShadow: saving
              ? null
              : [
                  BoxShadow(
                    color: AppColors.primaryShadow.withValues(alpha: 0.25),
                    blurRadius: 6,
                    offset: const Offset(0, 2),
                  ),
                ],
        ),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            if (saving)
              const SizedBox(
                width: 20,
                height: 20,
                child: CircularProgressIndicator(
                  strokeWidth: 2,
                  color: AppColors.textSecondary,
                ),
              )
            else
              const Icon(LucideIcons.download,
                  size: 20, color: AppColors.surface),
            const SizedBox(width: AppSpacing.md),
            Text(
              saving ? 'Saving...' : 'Save to Album',
              style: AppTypography.bodyMedium.copyWith(
                color: AppColors.surface,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

/// Report dialog - matches Pencil 5qKUB
class _ReportDialog extends StatefulWidget {
  const _ReportDialog({required this.parentContext});

  final BuildContext parentContext;

  static void show(BuildContext context) {
    showDialog<void>(
      context: context,
      barrierColor: Colors.black54,
      builder: (_) => _ReportDialog(parentContext: context),
    );
  }

  @override
  State<_ReportDialog> createState() => _ReportDialogState();
}

class _ReportDialogState extends State<_ReportDialog> {
  final _controller = TextEditingController();
  File? _pickedImage;
  final _picker = ImagePicker();
  bool _submitting = false;
  String? _errorText;

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  Future<void> _pickImage() async {
    final x = await _picker.pickImage(source: ImageSource.gallery);
    if (x != null && mounted) {
      setState(() => _pickedImage = File(x.path));
    }
  }

  Future<void> _submit() async {
    final content = _controller.text.trim();
    if (content.isEmpty) {
      setState(() => _errorText = 'Please describe the issue');
      return;
    }
    if (_pickedImage == null) {
      setState(() => _errorText = 'Please upload an image');
      return;
    }

    setState(() {
      _errorText = null;
      _submitting = true;
    });
    try {
      final file = _pickedImage!;
      final ext = file.path.split('.').last.toLowerCase();
      final contentType = ext == 'png'
          ? 'image/png'
          : ext == 'gif'
              ? 'image/gif'
              : 'image/jpeg';
      final fileName =
          'feedback_${DateTime.now().millisecondsSinceEpoch}.$ext';

      final presignedRes =
          await FeedbackApi.getUploadPresignedUrl(fileName: fileName);
      if (!presignedRes.isSuccess || presignedRes.data == null) {
        throw Exception(
            presignedRes.msg.isNotEmpty ? presignedRes.msg : 'Failed to get upload URL');
      }

      final data = presignedRes.data as Map<String, dynamic>;
      final uploadUrl = data['shed'] as String?;
      final filePath = data['hunt'] as String?;

      if (uploadUrl == null ||
          uploadUrl.isEmpty ||
          filePath == null ||
          filePath.isEmpty) {
        throw Exception('Invalid presigned URL response');
      }

      final bytes = await file.readAsBytes();
      final uploadResponse = await http.put(
        Uri.parse(uploadUrl),
        headers: {'Content-Type': contentType},
        body: bytes,
      );

      if (uploadResponse.statusCode < 200 ||
          uploadResponse.statusCode >= 300) {
        throw Exception('Upload failed: ${uploadResponse.statusCode}');
      }

      final submitRes = await FeedbackApi.submit(
        fileUrls: [filePath],
        content: content,
        contentType: 'text/plain',
      );

      if (!submitRes.isSuccess) {
        throw Exception(
            submitRes.msg.isNotEmpty ? submitRes.msg : 'Failed to submit report');
      }

      if (!mounted) return;
      Navigator.of(context).pop();
      if (widget.parentContext.mounted) {
        ScaffoldMessenger.of(widget.parentContext).showSnackBar(
          const SnackBar(
            content: Text('Report submitted'),
            behavior: SnackBarBehavior.floating,
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        setState(() => _errorText = e.toString().replaceAll('Exception: ', ''));
      }
    } finally {
      if (mounted) {
        setState(() => _submitting = false);
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Dialog(
      backgroundColor: Colors.transparent,
      insetPadding: const EdgeInsets.symmetric(horizontal: 24),
      child: Container(
        width: 342,
        padding: const EdgeInsets.all(24),
        decoration: BoxDecoration(
          color: AppColors.surface,
          borderRadius: BorderRadius.circular(16),
          boxShadow: [
            BoxShadow(
              color: Colors.black.withValues(alpha: 0.15),
              blurRadius: 24,
              offset: const Offset(0, 8),
            ),
          ],
        ),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text(
                  'Report',
                  style: AppTypography.bodyMedium.copyWith(
                    fontSize: 20,
                    fontWeight: FontWeight.w700,
                    color: AppColors.textPrimary,
                  ),
                ),
                GestureDetector(
                  onTap: () => Navigator.of(context).pop(),
                  child: const SizedBox(
                    width: 40,
                    height: 40,
                    child: Icon(
                      LucideIcons.x,
                      size: 24,
                      color: AppColors.textSecondary,
                    ),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 20),
            Container(
              height: 120,
              padding: const EdgeInsets.all(16),
              decoration: BoxDecoration(
                color: AppColors.background,
                borderRadius: BorderRadius.circular(12),
                border: Border.all(color: AppColors.border),
              ),
              child: TextField(
                controller: _controller,
                maxLines: null,
                decoration: const InputDecoration(
                  hintText: 'Describe the issue...',
                  hintStyle: TextStyle(color: AppColors.textMuted),
                  border: InputBorder.none,
                  contentPadding: EdgeInsets.zero,
                  isDense: true,
                ),
              ),
            ),
            const SizedBox(height: 20),
            GestureDetector(
              onTap: _pickImage,
              child: Container(
                height: 120,
                decoration: BoxDecoration(
                  color: AppColors.surfaceAlt,
                  borderRadius: BorderRadius.circular(12),
                  border: Border.all(
                    color: const Color(0xFFD4D4D8),
                    width: 2,
                  ),
                ),
                child: _pickedImage != null
                    ? ClipRRect(
                        borderRadius: BorderRadius.circular(10),
                        child: Image.file(
                          _pickedImage!,
                          fit: BoxFit.cover,
                          width: double.infinity,
                          height: double.infinity,
                        ),
                      )
                    : Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        children: [
                          Icon(
                            LucideIcons.image_plus,
                            size: 32,
                            color: AppColors.textMuted,
                          ),
                          const SizedBox(height: 8),
                          Text(
                            'Tap to upload image',
                            style: TextStyle(
                              color: AppColors.textSecondary,
                              fontSize: 14,
                            ),
                          ),
                        ],
                      ),
              ),
            ),
            if (_errorText != null) ...[
              const SizedBox(height: 12),
              Text(
                _errorText!,
                style: TextStyle(
                  color: AppColors.accentOrange,
                  fontSize: 14,
                ),
              ),
            ],
            const SizedBox(height: 20),
            GestureDetector(
              onTap: _submitting ? null : _submit,
              child: Container(
                height: 52,
                decoration: BoxDecoration(
                  color: _submitting
                      ? AppColors.textMuted
                      : const Color(0xFF7C3AED),
                  borderRadius: BorderRadius.circular(14),
                ),
                alignment: Alignment.center,
                child: _submitting
                    ? const SizedBox(
                        width: 20,
                        height: 20,
                        child: CircularProgressIndicator(
                          strokeWidth: 2,
                          color: AppColors.surface,
                        ),
                      )
                    : Text(
                        'Submit',
                        style: AppTypography.bodyMedium.copyWith(
                          color: AppColors.surface,
                          fontSize: 16,
                          fontWeight: FontWeight.w600,
                        ),
                      ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _ShareButton extends StatelessWidget {
  const _ShareButton({required this.onShare});

  final VoidCallback onShare;

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: onShare,
      child: Container(
        height: 52,
        decoration: BoxDecoration(
          color: AppColors.surface,
          borderRadius: BorderRadius.circular(14),
          border: Border.all(color: AppColors.border),
          boxShadow: const [
            BoxShadow(
              color: AppColors.shadowLight,
              blurRadius: 6,
              offset: Offset(0, 2),
            ),
          ],
        ),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const Icon(LucideIcons.share_2, size: 20, color: AppColors.primary),
            const SizedBox(width: AppSpacing.md),
            Text(
              'Share',
              style: AppTypography.bodyMedium.copyWith(
                color: AppColors.textPrimary,
              ),
            ),
          ],
        ),
      ),
    );
  }
}