import 'dart:io';
import 'dart:convert';
import 'package:flutter/material.dart';
// camera を使う（内蔵カメラ画面）
import 'package:camera/camera.dart';

import 'package:permission_handler/permission_handler.dart';
import 'package:google_mlkit_text_recognition/google_mlkit_text_recognition.dart';
import 'package:http/http.dart' as http;
import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
import 'package:webview_flutter/webview_flutter.dart';
import 'package:shared_preferences/shared_preferences.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await _requestPermissions();
  runApp(const MyApp());
}

/// カメラとストレージのパーミッション要求
Future<void> _requestPermissions() async {
  if (Platform.isAndroid) {
    await Permission.camera.request();
    await Permission.storage.request();
  } else if (Platform.isIOS) {
    await Permission.camera.request();
    await Permission.photos.request();
  }
}

/// メインアプリ
class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: '説明書検索アプリ',
      theme: ThemeData(useMaterial3: true),
      home: const OCRSearchScreen(),
    );
  }
}

/// OCRと検索画面
class OCRSearchScreen extends StatefulWidget {
  const OCRSearchScreen({super.key});

  @override
  State<OCRSearchScreen> createState() => _OCRSearchScreenState();
}

class _OCRSearchScreenState extends State<OCRSearchScreen> {
  File? _image;
  String _selectedModel = '';
  List<Map<String, String>> _searchResults = [];
  List<Map<String, String>> _favorites = [];
  bool _isLoading = false;
  bool _showAllResults = false;

  // 検索バー用
  final TextEditingController _manualController = TextEditingController();

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

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

  Future<void> _loadFavorites() async {
    final prefs = await SharedPreferences.getInstance();
    final favs = prefs.getStringList("favorites") ?? [];
    if (!mounted) return;
    setState(() {
      _favorites = favs
          .map((e) => Map<String, String>.from(json.decode(e)))
          .toList();
    });
  }

  Future<void> _saveFavorites() async {
    final prefs = await SharedPreferences.getInstance();
    final favs = _favorites.map((e) => json.encode(e)).toList();
    await prefs.setStringList("favorites", favs);
  }

  /// 画像を撮影→OCR→検索
  Future<void> _pickImageAndRecognizeText() async {
    // 内蔵カメラ画面へ
    final XFile? captured = await Navigator.push(
      context,
      MaterialPageRoute(builder: (_) => const CameraCapturePage()),
    );
    if (captured == null) return;

    setState(() {
      _isLoading = true;
      _image = File(captured.path);
      _selectedModel = '';
      _searchResults = [];
      _showAllResults = false;
    });

    try {
      final inputImage = InputImage.fromFile(_image!);
      final textRecognizer = TextRecognizer();
      final recognizedText = await textRecognizer.processImage(inputImage);
      await textRecognizer.close();

      final models = _extractModelNumbers(recognizedText.text);
      if (models.isNotEmpty) {
        final first = models.first;
        if (!mounted) return;
        setState(() {
          _selectedModel = first;
          _manualController.text = first; // 取得した型番を検索バーに反映
        });
        await _searchManuals(first);
      } else {
        if (!mounted) return;
        setState(() {
          _selectedModel = '';
        });
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('型番が見つかりませんでした。検索バーから手入力してください。')),
        );
      }
    } catch (e) {
      if (!mounted) return;
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(SnackBar(content: Text('エラー: $e')));
    } finally {
      if (!mounted) return;
      setState(() {
        _isLoading = false;
      });
    }
  }

  /// 型番候補を抽出（英字のみ/数字のみ除外、5〜20文字）
  List<String> _extractModelNumbers(String text) {
    final modelRegex = RegExp(r'\b[A-Z0-9][A-Z0-9\-_]{4,19}\b');
    final matches = modelRegex.allMatches(text);
    final candidates = matches.map((m) => m.group(0)!).toSet().toList();

    final filtered = candidates.where((c) {
      final hasLetter = RegExp(r'[A-Z]').hasMatch(c);
      final hasNumber = RegExp(r'\d').hasMatch(c);
      return hasLetter && hasNumber && c.length >= 5 && c.length <= 20;
    }).toList();

    filtered.sort(
      (a, b) => _scoreModelCandidate(b).compareTo(_scoreModelCandidate(a)),
    );

    return filtered;
  }

  int _scoreModelCandidate(String model) {
    int score = 0;
    if (model.length >= 6 && model.length <= 12) score += 1;
    if (RegExp(r'[A-Z]').hasMatch(model) &&
        RegExp(r'\d').hasMatch(model) &&
        RegExp(r'[-_]').hasMatch(model)) {
      score += 1;
    }
    if (RegExp(r'^[A-Z]').hasMatch(model)) score += 1;
    return score;
  }

  /// Google カスタム検索 API を使って説明書を検索
  Future<void> _searchManuals(String modelNumber) async {
    const apiKey = 'AIzaSyAEpUlGntFdDygHBgleEmig6gleFnvcEPQ'; // ←あなたのキー
    const searchEngineId = '41e4997a6d32d42b7'; // ←あなたのCSE ID

    final query = Uri.encodeComponent('$modelNumber 説明書 PDF');
    final url = Uri.parse(
      'https://www.googleapis.com/customsearch/v1?key=$apiKey&cx=$searchEngineId&q=$query',
    );

    final response = await http.get(url);

    if (response.statusCode == 200) {
      final data = json.decode(response.body);
      final items = data['items'] as List<dynamic>?;

      if (items != null) {
        final results = items.map((item) {
          final link = item['link'].toString();
          final title = item['title'].toString();
          return {'link': link, 'title': title};
        }).toList();

        results.sort(
          (a, b) => _scoreHostHints(
            b['link']!,
            b['title']!,
          ).compareTo(_scoreHostHints(a['link']!, a['title']!)),
        );

        if (!mounted) return;
        setState(() {
          _searchResults = results;
        });
      } else {
        if (!mounted) return;
        setState(() => _searchResults = []);
      }
    } else {
      debugPrint('検索エラー: ${response.statusCode}');
      if (!mounted) return;
      setState(() => _searchResults = []);
    }
  }

  int _scoreHostHints(String url, String title) {
    final lowerUrl = url.toLowerCase();
    final lowerTitle = title.toLowerCase();

    final officialWords = [
      "support",
      "downloads",
      "manual",
      "docs",
      "help",
      "service",
      "global",
      "jp",
      "downloadcenter",
      "drivers",
      "product-support",
      "customer-support",
      "knowledgebase",
      "faq",
      "manuals",
    ];

    final nonOfficialWords = [
      "amazon",
      "rakuten",
      "yahoo",
      "mercari",
      "kakaku",
      "store",
      "shop",
      "auction",
    ];

    int score = 0;
    if (lowerUrl.endsWith(".pdf")) score += 5;

    for (final word in officialWords) {
      if (lowerUrl.contains(word) || lowerTitle.contains(word)) {
        score += 3;
      }
    }
    for (final word in nonOfficialWords) {
      if (lowerUrl.contains(word) || lowerTitle.contains(word)) {
        score -= 3;
      }
    }
    return score;
  }

  /// お気に入り登録時に名前入力
  Future<String?> _askFavoriteName(
    BuildContext context,
    String defaultName,
  ) async {
    String customName = '';
    await showDialog(
      context: context,
      builder: (context) {
        return AlertDialog(
          title: const Text("お気に入りに名前を付ける"),
          content: TextField(
            autofocus: true,
            decoration: const InputDecoration(
              hintText: "例: 掃除機の説明書（未入力なら自動保存）",
            ),
            onChanged: (value) => customName = value,
          ),
          actions: [
            TextButton(
              child: const Text("キャンセル"),
              onPressed: () => Navigator.pop(context),
            ),
            TextButton(
              child: const Text("保存"),
              onPressed: () => Navigator.pop(context),
            ),
          ],
        );
      },
    );
    return customName.isEmpty ? defaultName : customName;
  }

  /// お気に入り登録/解除
  void _toggleFavorite(BuildContext context, Map<String, String> item) async {
    final exists = _favorites.any((f) => f['link'] == item['link']);
    if (exists) {
      setState(() {
        _favorites.removeWhere((f) => f['link'] == item['link']);
      });
      _saveFavorites();
      return;
    }

    final customName = await _askFavoriteName(context, item['title'] ?? "説明書");
    if (!mounted) return;

    final favItem = {
      'link': item['link']!,
      'title': item['title']!,
      'customName': customName!,
    };
    setState(() {
      _favorites.add(favItem);
    });
    _saveFavorites();
  }

  /// 手動検索
  Future<void> _searchByManualInput() async {
    final input = _manualController.text.trim();
    if (input.isEmpty) return;

    setState(() {
      _selectedModel = input;
      _searchResults = [];
      _showAllResults = false;
    });

    await _searchManuals(input);
  }

  @override
  Widget build(BuildContext context) {
    final resultsToShow = _showAllResults
        ? _searchResults
        : _searchResults.take(5).toList();

    return Scaffold(
      appBar: AppBar(
        title: const Text('説明書検索アプリ'),
        actions: [
          TextButton.icon(
            onPressed: () async {
              await Navigator.push(
                context,
                MaterialPageRoute(
                  builder: (_) => FavoritesPage(
                    favorites: _favorites,
                    onUpdate: (favs) {
                      setState(() => _favorites = favs);
                      _saveFavorites();
                    },
                  ),
                ),
              );
            },
            icon: const Icon(Icons.star, color: Colors.orange),
            label: const Text('お気に入り', style: TextStyle(color: Colors.orange)),
          ),
          const SizedBox(width: 8),
        ],
      ),

      // 画面下中央にカメラボタン（FAB）
      floatingActionButton: FloatingActionButton(
        onPressed: _pickImageAndRecognizeText,
        backgroundColor: Colors.blue,
        child: const Icon(Icons.camera_alt, size: 32, color: Colors.white),
      ),
      floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,

      body: SingleChildScrollView(
        padding: const EdgeInsets.fromLTRB(16, 12, 16, 90), // FABと被らないように下余白
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            // 常時表示の検索バー
            TextField(
              controller: _manualController,
              textInputAction: TextInputAction.search,
              onSubmitted: (_) => _searchByManualInput(),
              onChanged: (_) => setState(() {}), // ×ボタンの表示を即時反映
              decoration: InputDecoration(
                hintText: '型番を手入力して検索（例：SPF-013）',
                prefixIcon: const Icon(Icons.search),
                suffixIcon: Row(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    if (_manualController.text.isNotEmpty)
                      IconButton(
                        icon: const Icon(Icons.clear),
                        onPressed: () {
                          setState(() {
                            _manualController.clear();
                          });
                        },
                      ),
                    IconButton(
                      icon: const Icon(Icons.arrow_forward),
                      onPressed: _searchByManualInput,
                    ),
                  ],
                ),
                border: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(12),
                ),
                filled: true,
              ),
            ),
            const SizedBox(height: 12),

            if (_isLoading) const Center(child: CircularProgressIndicator()),
            if (_image != null) ...[
              Image.file(_image!),
              const SizedBox(height: 16),
            ],
            if (_selectedModel.isNotEmpty)
              Padding(
                padding: const EdgeInsets.only(bottom: 8),
                child: Text('抽出された型番（自動選択）: $_selectedModel'),
              ),

            if (_searchResults.isNotEmpty) ...[
              const Text('検索結果:'),
              const SizedBox(height: 8),
              ...resultsToShow.map((result) {
                final link = result['link']!;
                final title = result['title']!;
                final isPdf = link.toLowerCase().endsWith(".pdf");
                final isFav = _favorites.any((f) => f['link'] == link);

                return Card(
                  margin: const EdgeInsets.symmetric(vertical: 6),
                  child: ListTile(
                    leading: Icon(
                      isPdf ? Icons.picture_as_pdf : Icons.language,
                      color: isPdf ? Colors.red : Colors.blue,
                    ),
                    title: Text(isPdf ? "📄 PDF: $title" : "🌐 Web: $title"),
                    trailing: IconButton(
                      icon: Icon(
                        isFav ? Icons.star : Icons.star_border,
                        color: Colors.orange,
                      ),
                      onPressed: () => _toggleFavorite(context, result),
                    ),
                    onTap: () {
                      Navigator.push(
                        context,
                        MaterialPageRoute(
                          builder: (_) => isPdf
                              ? PDFViewerPage(url: link)
                              : WebViewerPage(url: link),
                        ),
                      );
                    },
                  ),
                );
              }),
              if (!_showAllResults && _searchResults.length > 5)
                TextButton(
                  onPressed: () => setState(() => _showAllResults = true),
                  child: const Text("もっと見る"),
                ),
            ],
          ],
        ),
      ),
    );
  }
}

/// お気に入り一覧画面
class FavoritesPage extends StatefulWidget {
  final List<Map<String, String>> favorites;
  final Function(List<Map<String, String>>) onUpdate;

  const FavoritesPage({
    super.key,
    required this.favorites,
    required this.onUpdate,
  });

  @override
  State<FavoritesPage> createState() => _FavoritesPageState();
}

class _FavoritesPageState extends State<FavoritesPage> {
  late List<Map<String, String>> _favorites;

  @override
  void initState() {
    super.initState();
    _favorites = List.from(widget.favorites);
  }

  Future<String?> _askFavoriteName(
    BuildContext context,
    String defaultName,
  ) async {
    String customName = '';
    await showDialog(
      context: context,
      builder: (context) {
        return AlertDialog(
          title: const Text("名前を変更"),
          content: TextField(
            autofocus: true,
            decoration: const InputDecoration(hintText: "新しい名前"),
            onChanged: (value) => customName = value,
          ),
          actions: [
            TextButton(
              child: const Text("キャンセル"),
              onPressed: () => Navigator.pop(context),
            ),
            TextButton(
              child: const Text("保存"),
              onPressed: () => Navigator.pop(context),
            ),
          ],
        );
      },
    );
    return customName.isEmpty ? defaultName : customName;
  }

  Future<bool?> _confirmDelete(BuildContext context) async {
    return showDialog<bool>(
      context: context,
      builder: (context) {
        return AlertDialog(
          title: const Text("削除しますか？"),
          actions: [
            TextButton(
              child: const Text("いいえ"),
              onPressed: () => Navigator.pop(context, false),
            ),
            TextButton(
              child: const Text("はい"),
              onPressed: () => Navigator.pop(context, true),
            ),
          ],
        );
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text("お気に入り一覧")),
      body: ListView.builder(
        itemCount: _favorites.length,
        itemBuilder: (context, index) {
          final item = _favorites[index];
          final link = item['link']!;
          final title = item['title']!;
          final customName = item['customName'] ?? title;
          final isPdf = link.toLowerCase().endsWith(".pdf");

          return Card(
            margin: const EdgeInsets.symmetric(vertical: 6, horizontal: 8),
            child: ListTile(
              leading: Icon(
                isPdf ? Icons.picture_as_pdf : Icons.language,
                color: isPdf ? Colors.red : Colors.blue,
              ),
              title: Text(customName),
              subtitle: Text(
                title,
                maxLines: 1,
                overflow: TextOverflow.ellipsis,
              ),
              trailing: PopupMenuButton<String>(
                onSelected: (value) async {
                  if (value == 'edit') {
                    final newName = await _askFavoriteName(context, customName);
                    if (!mounted) return;
                    setState(() {
                      _favorites[index]['customName'] = newName!;
                    });
                    widget.onUpdate(_favorites);
                  } else if (value == 'delete') {
                    final ok = await _confirmDelete(context);
                    if (ok == true) {
                      if (!mounted) return;
                      setState(() {
                        _favorites.removeAt(index);
                      });
                      widget.onUpdate(_favorites);
                    }
                  }
                },
                itemBuilder: (context) => const [
                  PopupMenuItem(value: 'edit', child: Text("✏️ 名前を変更")),
                  PopupMenuItem(value: 'delete', child: Text("🗑 削除")),
                ],
              ),
              onTap: () {
                Navigator.push(
                  context,
                  MaterialPageRoute(
                    builder: (_) => isPdf
                        ? PDFViewerPage(url: link)
                        : WebViewerPage(url: link),
                  ),
                );
              },
            ),
          );
        },
      ),
    );
  }
}

/// ===== 内蔵カメラ画面（シャッター下固定） =====
class CameraCapturePage extends StatefulWidget {
  const CameraCapturePage({super.key});

  @override
  State<CameraCapturePage> createState() => _CameraCapturePageState();
}

class _CameraCapturePageState extends State<CameraCapturePage> {
  CameraController? _controller;
  List<CameraDescription> _cameras = [];
  bool _isBusy = true;
  bool _torchOn = false;
  int _index = 0; // 0:背面→1:前面

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

  Future<void> _initCameras() async {
    try {
      _cameras = await availableCameras();
      if (_cameras.isEmpty) {
        if (!mounted) return;
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(const SnackBar(content: Text('カメラが見つかりませんでした')));
        Navigator.pop(context);
        return;
      }
      _index = _cameras.indexWhere(
        (c) => c.lensDirection == CameraLensDirection.back,
      );
      if (_index < 0) _index = 0;
      await _startController(_cameras[_index]);
    } catch (e) {
      if (!mounted) return;
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(SnackBar(content: Text('カメラ初期化エラー: $e')));
      Navigator.pop(context);
    }
  }

  Future<void> _startController(CameraDescription desc) async {
    _controller?.dispose();
    _controller = CameraController(desc, ResolutionPreset.medium);
    await _controller!.initialize();
    if (!mounted) return;
    setState(() {
      _isBusy = false;
    });
  }

  Future<void> _toggleTorch() async {
    if (_controller == null) return;
    _torchOn = !_torchOn;
    await _controller!.setFlashMode(_torchOn ? FlashMode.torch : FlashMode.off);
    if (!mounted) return;
    setState(() {});
  }

  Future<void> _switchCamera() async {
    if (_cameras.length < 2) return;
    _index = (_index + 1) % _cameras.length;
    setState(() => _isBusy = true);
    await _startController(_cameras[_index]);
  }

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

  @override
  Widget build(BuildContext context) {
    final preview = (_controller != null && _controller!.value.isInitialized)
        ? CameraPreview(_controller!)
        : const SizedBox.shrink();

    return Scaffold(
      backgroundColor: Colors.black,
      body: SafeArea(
        child: Stack(
          children: [
            Positioned.fill(child: preview),
            // 下部コントロールバー（シャッター固定）
            Positioned(
              left: 0,
              right: 0,
              bottom: 0,
              child: Container(
                padding: const EdgeInsets.symmetric(
                  horizontal: 24,
                  vertical: 16,
                ),
                decoration: BoxDecoration(
                  gradient: LinearGradient(
                    colors: [
                      Colors.black.withOpacity(0.0),
                      Colors.black.withOpacity(0.6),
                      Colors.black.withOpacity(0.9),
                    ],
                    begin: Alignment.topCenter,
                    end: Alignment.bottomCenter,
                  ),
                ),
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    // トーチ
                    IconButton(
                      icon: Icon(
                        _torchOn ? Icons.flash_on : Icons.flash_off,
                        color: Colors.white,
                        size: 28,
                      ),
                      onPressed: _toggleTorch,
                    ),
                    // シャッター（大きい円）
                    GestureDetector(
                      onTap: _isBusy
                          ? null
                          : () async {
                              try {
                                setState(() => _isBusy = true);
                                final file = await _controller!.takePicture();
                                if (!mounted) return;
                                Navigator.pop(context, file);
                              } catch (e) {
                                if (!mounted) return;
                                ScaffoldMessenger.of(context).showSnackBar(
                                  SnackBar(content: Text('撮影エラー: $e')),
                                );
                                setState(() => _isBusy = false);
                              }
                            },
                      child: Container(
                        width: 76,
                        height: 76,
                        decoration: BoxDecoration(
                          shape: BoxShape.circle,
                          border: Border.all(color: Colors.white, width: 4),
                          color: Colors.white.withOpacity(0.15),
                        ),
                        child: const Center(
                          child: CircleAvatar(
                            radius: 28,
                            backgroundColor: Colors.white,
                          ),
                        ),
                      ),
                    ),
                    // カメラ切替
                    IconButton(
                      icon: const Icon(
                        Icons.cameraswitch,
                        color: Colors.white,
                        size: 28,
                      ),
                      onPressed: _switchCamera,
                    ),
                  ],
                ),
              ),
            ),
            if (_isBusy)
              const Positioned.fill(
                child: IgnorePointer(
                  ignoring: true,
                  child: Center(
                    child: CircularProgressIndicator(color: Colors.white),
                  ),
                ),
              ),
            // 戻るボタン（左上）
            Positioned(
              left: 8,
              top: 8,
              child: IconButton(
                icon: const Icon(Icons.close, color: Colors.white),
                onPressed: () => Navigator.pop(context),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

/// PDFビューア画面
class PDFViewerPage extends StatelessWidget {
  final String url;
  const PDFViewerPage({super.key, required this.url});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text("PDFビューア")),
      body: SfPdfViewer.network(url),
    );
  }
}

/// Webビューア画面
class WebViewerPage extends StatelessWidget {
  final String url;
  const WebViewerPage({super.key, required this.url});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text("Webマニュアル")),
      body: WebViewWidget(
        controller: WebViewController()
          ..setJavaScriptMode(JavaScriptMode.unrestricted)
          ..loadRequest(Uri.parse(url)),
      ),
    );
  }
}