import 'dart:io';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:lucide_icons/lucide_icons.dart';
import '../models/sake_item.dart';
import '../services/draft_service.dart';
import '../services/network_service.dart';
import '../theme/app_colors.dart';

/// 未解析Draft一覧・一括解析画面
///
/// Phase 1: オフライン対応機能
/// オフライン時に撮影した写真（Draft）の一覧を表示し、
/// オンライン復帰後に一括解析できます。
class PendingAnalysisScreen extends ConsumerStatefulWidget {
  const PendingAnalysisScreen({super.key});

  @override
  ConsumerState<PendingAnalysisScreen> createState() => _PendingAnalysisScreenState();
}

class _PendingAnalysisScreenState extends ConsumerState<PendingAnalysisScreen> {
  List<SakeItem> _pendingDrafts = [];
  bool _isLoading = true;
  bool _isAnalyzing = false;
  int _analyzedCount = 0;
  int _totalCount = 0;
  String? _errorMessage;

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

  Future<void> _loadPendingDrafts() async {
    setState(() {
      _isLoading = true;
      _errorMessage = null;
    });

    try {
      final drafts = await DraftService.getPendingDrafts();
      setState(() {
        _pendingDrafts = drafts;
        _isLoading = false;
      });
    } catch (e) {
      setState(() {
        _errorMessage = 'Draft読み込みエラー: $e';
        _isLoading = false;
      });
    }
  }

  Future<void> _analyzeAllDrafts() async {
    final appColors = Theme.of(context).extension<AppColors>()!;

    // オンライン確認
    final isOnline = await NetworkService.isOnline();
    if (!isOnline) {
      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: const Text('オフライン状態です。インターネット接続を確認してください。'),
          backgroundColor: appColors.error,
          duration: const Duration(seconds: 4),
        ),
      );
      return;
    }

    setState(() {
      _isAnalyzing = true;
      _analyzedCount = 0;
      _totalCount = _pendingDrafts.length;
      _errorMessage = null;
    });

    try {
      final result = await DraftService.analyzeAllDrafts(
        onProgress: (progress, total) {
          if (mounted) {
            setState(() {
              _analyzedCount = progress;
            });
          }
        },
      );

      if (!mounted) return;

      // 解析完了後、リスト再読み込み
      await _loadPendingDrafts();

      // 結果通知
      final successCount = result['success'] as int;
      final failedCount = result['failed'] as int;
      final errors = result['errors'] as List<String>;

      if (failedCount > 0) {
        // 一部失敗
        setState(() {
          _errorMessage = '解析完了: $successCount成功, $failedCount失敗\n\n失敗詳細:\n${errors.join('\n')}';
        });
      } else {
        // 全成功
        if (!mounted) return;
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('すべてのDraft（$successCount件）を解析しました'),
            backgroundColor: appColors.success,
            duration: const Duration(seconds: 3),
          ),
        );

        // 全件解析完了なら画面を閉じる
        if (_pendingDrafts.isEmpty) {
          if (!mounted) return;
          Navigator.of(context).pop();
        }
      }
    } catch (e) {
      setState(() {
        _errorMessage = '一括解析エラー: $e';
      });
    } finally {
      setState(() {
        _isAnalyzing = false;
      });
    }
  }

  Future<void> _deleteDraft(SakeItem draft) async {
    final appColors = Theme.of(context).extension<AppColors>()!;

    final confirm = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('Draft削除確認'),
        content: const Text('この写真を削除しますか？\n（ギャラリーには残ります）'),
        actions: [
          TextButton(
            onPressed: () => Navigator.of(context).pop(false),
            child: const Text('キャンセル'),
          ),
          TextButton(
            onPressed: () => Navigator.of(context).pop(true),
            style: TextButton.styleFrom(foregroundColor: appColors.error),
            child: const Text('削除'),
          ),
        ],
      ),
    );

    if (confirm != true) return;

    try {
      await DraftService.deleteDraft(draft.key);
      await _loadPendingDrafts();

      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(
          content: Text('Draftを削除しました'),
          duration: Duration(seconds: 3),
        ),
      );

      // 全件削除された場合は画面を閉じる
      if (_pendingDrafts.isEmpty) {
        Navigator.of(context).pop();
      }
    } catch (e) {
      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text('削除エラー: $e'),
          duration: const Duration(seconds: 5),
        ),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final appColors = Theme.of(context).extension<AppColors>()!;

    return Scaffold(
      appBar: AppBar(
        title: const Text('未解析の写真', style: TextStyle(fontWeight: FontWeight.bold)),
        actions: [
          if (_pendingDrafts.isNotEmpty && !_isAnalyzing)
            IconButton(
              icon: const Icon(LucideIcons.trash2),
              tooltip: 'すべて削除',
              onPressed: () async {
                // BuildContextキャプチャ（async gapの前）
                if (!mounted) return;
                final navigator = Navigator.of(context);
                final messenger = ScaffoldMessenger.of(context);
                
                final confirm = await showDialog<bool>(
                  context: context,
                  builder: (context) => AlertDialog(
                    title: const Text('全件削除確認'),
                    content: Text('${_pendingDrafts.length}件のDraftをすべて削除しますか？'),
                    actions: [
                      TextButton(
                        onPressed: () => Navigator.of(context).pop(false),
                        child: const Text('キャンセル'),
                      ),
                      TextButton(
                        onPressed: () => Navigator.of(context).pop(true),
                        style: TextButton.styleFrom(foregroundColor: appColors.error),
                        child: const Text('すべて削除'),
                      ),
                    ],
                  ),
                );

                if (!mounted) return;
                if (confirm != true) return;

                final count = await DraftService.deleteAllDrafts();
                await _loadPendingDrafts();

                // async gap後はキャプチャした変数を使用
                if (!mounted) return;
                messenger.showSnackBar(
                  SnackBar(
                    content: Text('$count件のDraftを削除しました'),
                    duration: const Duration(seconds: 3),
                  ),
                );

                if (!mounted) return;
                navigator.pop();
              },
            ),
        ],
      ),
      body: _isLoading
          ? const Center(child: CircularProgressIndicator())
          : _errorMessage != null
              ? Center(
                  child: Padding(
                    padding: const EdgeInsets.all(24.0),
                    child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        Icon(LucideIcons.alertCircle, size: 60, color: appColors.error),
                        const SizedBox(height: 16),
                        Text(
                          _errorMessage!,
                          textAlign: TextAlign.center,
                          style: TextStyle(color: appColors.error),
                        ),
                        const SizedBox(height: 24),
                        ElevatedButton(
                          onPressed: _loadPendingDrafts,
                          child: const Text('再読み込み'),
                        ),
                      ],
                    ),
                  ),
                )
              : _pendingDrafts.isEmpty
                  ? Center(
                      child: Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        children: [
                          Icon(LucideIcons.checkCircle, size: 60, color: appColors.success),
                          const SizedBox(height: 16),
                          const Text(
                            '未解析の写真はありません',
                            style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
                          ),
                          const SizedBox(height: 8),
                          Text(
                            'すべての写真の解析が完了しています',
                            style: TextStyle(color: appColors.textSecondary),
                          ),
                        ],
                      ),
                    )
                  : Column(
                      children: [
                        // 進捗表示（解析中のみ）
                        if (_isAnalyzing)
                          Container(
                            padding: const EdgeInsets.all(16),
                            color: appColors.brandPrimary.withValues(alpha: 0.1),
                            child: Column(
                              children: [
                                Row(
                                  children: [
                                    const SizedBox(
                                      width: 24,
                                      height: 24,
                                      child: CircularProgressIndicator(strokeWidth: 3),
                                    ),
                                    const SizedBox(width: 12),
                                    Text(
                                      '解析中... $_analyzedCount / $_totalCount',
                                      style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
                                    ),
                                  ],
                                ),
                                const SizedBox(height: 8),
                                LinearProgressIndicator(
                                  value: _totalCount > 0 ? _analyzedCount / _totalCount : 0,
                                ),
                              ],
                            ),
                          ),

                        // Draft一覧
                        Expanded(
                          child: ListView.builder(
                            padding: const EdgeInsets.all(16),
                            itemCount: _pendingDrafts.length,
                            itemBuilder: (context, index) {
                              final draft = _pendingDrafts[index];
                              final photoPath = draft.draftPhotoPath;

                              return Card(
                                margin: const EdgeInsets.only(bottom: 12),
                                child: ListTile(
                                  contentPadding: const EdgeInsets.all(12),
                                  leading: photoPath != null && File(photoPath).existsSync()
                                      ? ClipRRect(
                                          borderRadius: BorderRadius.circular(8),
                                          child: Image.file(
                                            File(photoPath),
                                            width: 60,
                                            height: 60,
                                            fit: BoxFit.cover,
                                          ),
                                        )
                                      : Container(
                                          width: 60,
                                          height: 60,
                                          decoration: BoxDecoration(
                                            color: Colors.grey.shade300,
                                            borderRadius: BorderRadius.circular(8),
                                          ),
                                          child: const Icon(LucideIcons.image, color: Colors.grey),
                                        ),
                                  title: const Text(
                                    '解析待ち',
                                    style: TextStyle(fontWeight: FontWeight.bold),
                                  ),
                                  subtitle: Text(
                                    '撮影日時: ${draft.metadata.createdAt.toString().substring(0, 16)}',
                                    style: TextStyle(fontSize: 12, color: appColors.textSecondary),
                                  ),
                                  trailing: IconButton(
                                    icon: Icon(LucideIcons.trash2, color: appColors.error),
                                    onPressed: () => _deleteDraft(draft),
                                  ),
                                ),
                              );
                            },
                          ),
                        ),

                        // 一括解析ボタン
                        if (_pendingDrafts.isNotEmpty)
                          Container(
                            padding: const EdgeInsets.all(16),
                            decoration: BoxDecoration(
                              color: Colors.white,
                              boxShadow: [
                                BoxShadow(
                                  color: Colors.black.withValues(alpha: 0.1),
                                  blurRadius: 8,
                                  offset: const Offset(0, -2),
                                ),
                              ],
                            ),
                            child: SafeArea(
                              child: SizedBox(
                                width: double.infinity,
                                height: 56,
                                child: ElevatedButton(
                                  onPressed: _isAnalyzing ? null : _analyzeAllDrafts,
                                  style: ElevatedButton.styleFrom(
                                    backgroundColor: appColors.brandPrimary,
                                    foregroundColor: Colors.white,
                                    disabledBackgroundColor: Colors.grey.shade400,
                                    shape: RoundedRectangleBorder(
                                      borderRadius: BorderRadius.circular(12),
                                    ),
                                  ),
                                  child: _isAnalyzing
                                      ? const Row(
                                          mainAxisAlignment: MainAxisAlignment.center,
                                          children: [
                                            SizedBox(
                                              width: 20,
                                              height: 20,
                                              child: CircularProgressIndicator(
                                                color: Colors.white,
                                                strokeWidth: 2,
                                              ),
                                            ),
                                            SizedBox(width: 12),
                                            Text('解析中...', style: TextStyle(fontSize: 16)),
                                          ],
                                        )
                                      : Row(
                                          mainAxisAlignment: MainAxisAlignment.center,
                                          children: [
                                            const Icon(LucideIcons.sparkles, size: 20),
                                            const SizedBox(width: 8),
                                            Text(
                                              'すべて解析（${_pendingDrafts.length}件）',
                                              style: const TextStyle(
                                                fontSize: 16,
                                                fontWeight: FontWeight.bold,
                                              ),
                                            ),
                                          ],
                                        ),
                                ),
                              ),
                            ),
                          ),
                      ],
                    ),
    );
  }
}