import 'package:flutter/services.dart';

class ShareIntentService {
  static const _platform = MethodChannel('app.channel.shared.data');
  static ShareIntentService? _instance;

  // Singleton pattern
  factory ShareIntentService() {
    _instance ??= ShareIntentService._internal();
    return _instance!;
  }

  ShareIntentService._internal();

  /// Retrieves shared text from the platform channel
  /// Returns null if no shared text is available
  Future<String?> getSharedText() async {
    try {
      final String? sharedText = await _platform.invokeMethod('getSharedText');
      return sharedText;
    } on PlatformException catch (e) {
      // Log error in production app
      print('Failed to get shared text: ${e.message}');
      return null;
    }
  }

  /// Checks if the text is a Google Maps link
  bool isGoogleMapsLink(String text) {
    return text.contains('maps.google.com') ||
        text.contains('maps.app.goo.gl') ||
        text.contains('goo.gl/maps');
  }

  /// Extracts metadata from a Google Maps link
  MapsLinkMetadata extractMetadata(String mapsLink) {
    String? placeName;
    String? latitude;
    String? longitude;
    String? address;

    // Extract place name from URL
    final placeMatch = RegExp(r'/place/([^/]+)').firstMatch(mapsLink);
    if (placeMatch != null) {
      placeName = Uri.decodeComponent(
        placeMatch.group(1)!,
      ).replaceAll('+', ' ');
    }

    // Extract coordinates
    final coordMatch = RegExp(
      r'@(-?\d+\.\d+),(-?\d+\.\d+)',
    ).firstMatch(mapsLink);
    if (coordMatch != null) {
      latitude = coordMatch.group(1);
      longitude = coordMatch.group(2);
    }

    // Extract search query/address
    final searchMatch = RegExp(r'/search/([^/?]+)').firstMatch(mapsLink);
    if (searchMatch != null) {
      address = Uri.decodeComponent(searchMatch.group(1)!).replaceAll('+', ' ');
      // Use address as place name if name not found
      placeName ??= address;
    }

    // Extract from data parameter (alternative format)
    final dataMatch = RegExp(r'[?&]q=([^&]+)').firstMatch(mapsLink);
    if (dataMatch != null && placeName == null) {
      final query = Uri.decodeComponent(dataMatch.group(1)!);
      // Check if it's coordinates
      final coordPattern = RegExp(r'^(-?\d+\.\d+),(-?\d+\.\d+)$');
      final coords = coordPattern.firstMatch(query);
      if (coords != null) {
        latitude ??= coords.group(1);
        longitude ??= coords.group(2);
      } else {
        placeName = query.replaceAll('+', ' ');
      }
    }

    return MapsLinkMetadata(
      url: mapsLink,
      placeName: placeName ?? 'Unknown Location',
      latitude: latitude,
      longitude: longitude,
      address: address,
    );
  }
}

/// Data class for Google Maps link metadata
class MapsLinkMetadata {
  final String url;
  final String placeName;
  final String? latitude;
  final String? longitude;
  final String? address;

  const MapsLinkMetadata({
    required this.url,
    required this.placeName,
    this.latitude,
    this.longitude,
    this.address,
  });

  String get coordinates {
    if (latitude != null && longitude != null) {
      return '$latitude, $longitude';
    }
    return '';
  }

  bool get hasCoordinates => latitude != null && longitude != null;
}