import 'dart:convert';
import 'package:flutter/foundation.dart';
import 'package:http/http.dart' as http;
import 'road_alert_models.dart';
import 'road_alert_provider_interface.dart';

/// Commercial telematics provider for HERE Technologies Safety Cameras.
///
/// Queries HERE Safety Cameras circular search REST endpoint for
/// verified mobile speed traps, stationary radar, and red light cameras.
class HereRoadAlertProvider implements RoadAlertProvider {
  final http.Client _client;

  HereRoadAlertProvider({http.Client? client})
      : _client = client ?? http.Client();

  @override
  String get id => 'here_safety_cameras';

  @override
  String get name => 'HERE Safety Cameras';

  @override
  Set<RoadAlertCategory> get supportedCategories => const {
        RoadAlertCategory.police,
        RoadAlertCategory.speedCamera,
        RoadAlertCategory.hazard,
      };

  @override
  Future<RoadAlertProviderStatus> testConnection(String apiKey) async {
    final key = apiKey.trim();
    if (key.isEmpty) {
      return RoadAlertProviderStatus.notConfigured;
    }

    try {
      // Test circular search around downtown Los Angeles (US sample point)
      final url = Uri.parse(
        'https://safetycameras.hereapi.com/v2/search?in=circle:34.0522,-118.2437;r=500&apiKey=$key',
      );
      final response =
          await _client.get(url).timeout(const Duration(seconds: 6));

      if (response.statusCode == 200) {
        return RoadAlertProviderStatus.connected;
      } else if (response.statusCode == 401 || response.statusCode == 403) {
        return RoadAlertProviderStatus.authError;
      } else if (response.statusCode == 429) {
        return RoadAlertProviderStatus.rateLimited;
      }
      return RoadAlertProviderStatus.networkError;
    } catch (_) {
      return RoadAlertProviderStatus.networkError;
    }
  }

  @override
  Future<List<RoadAlert>> getAlerts({
    required double latitude,
    required double longitude,
    required double radiusMeters,
    String? apiKey,
  }) async {
    final key = apiKey?.trim();
    if (key == null || key.isEmpty) {
      return [];
    }

    try {
      final r = radiusMeters.clamp(100.0, 10000.0).toInt();
      final url = Uri.parse(
        'https://safetycameras.hereapi.com/v2/search?in=circle:$latitude,$longitude;r=$r&apiKey=$key',
      );

      final response =
          await _client.get(url).timeout(const Duration(seconds: 8));
      if (response.statusCode != 200) {
        return [];
      }

      final data = json.decode(response.body);
      final List<dynamic> items =
          data['items'] ?? (data['safetyCameras'] ?? []);
      final List<RoadAlert> alerts = [];

      for (var item in items) {
        if (item is Map<String, dynamic>) {
          try {
            final alert = parseHereItem(item);
            if (alert != null) {
              alerts.add(alert);
            }
          } catch (e) {
            if (kDebugMode) {
              debugPrint('[HereRoadAlertProvider] Item parse error: $e');
            }
          }
        }
      }

      return alerts;
    } catch (e) {
      if (kDebugMode) {
        debugPrint('[HereRoadAlertProvider] Request error: $e');
      }
      return [];
    }
  }

  /// Parses a single item from the HERE Safety Cameras response
  RoadAlert? parseHereItem(Map<String, dynamic> item) {
    final id = item['id']?.toString() ?? 'here_${item.hashCode}';
    final typeStr =
        (item['type'] ?? item['cameraType'] ?? '').toString().toUpperCase();

    // Map HERE camera / incident types to RoadAlertCategory
    final RoadAlertCategory category;
    final RoadAlertSeverity severity;
    if (typeStr.contains('MOBILE') || typeStr.contains('POLICE')) {
      category = RoadAlertCategory.police;
      severity = RoadAlertSeverity.high;
    } else if (typeStr.contains('SPEED') ||
        typeStr.contains('RED_LIGHT') ||
        typeStr.contains('CAMERA') ||
        typeStr.contains('FIXED')) {
      category = RoadAlertCategory.speedCamera;
      severity = RoadAlertSeverity.medium;
    } else {
      category = RoadAlertCategory.hazard;
      severity = RoadAlertSeverity.low;
    }

    // Coordinates
    final position = item['position'] ?? item['coordinate'] ?? {};
    final lat = (position['lat'] ?? position['latitude'] as num?)?.toDouble();
    final lng = (position['lng'] ?? position['longitude'] as num?)?.toDouble();
    if (lat == null || lng == null) return null;

    final road = item['road'] ?? item['roadName']?.toString();
    final speedLimit = item['speedLimit'];
    final unit = item['speedLimitUnit'] ?? 'MPH';
    final heading = (item['heading'] ?? item['bearing'] as num?)?.toDouble();

    String desc = item['description']?.toString() ?? '';
    if (desc.isEmpty) {
      if (category == RoadAlertCategory.police) {
        desc = speedLimit != null
            ? 'Mobile Speed Trap ($speedLimit $unit zone)'
            : 'Mobile Police Enforcement Zone';
      } else {
        desc = speedLimit != null
            ? 'Safety Speed Camera ($speedLimit $unit)'
            : 'Enforcement Camera';
      }
    }

    return RoadAlert(
      id: id,
      providerId: 'here_safety_cameras',
      category: category,
      latitude: lat,
      longitude: lng,
      heading: heading,
      roadName: road,
      description: desc,
      reportedAt: DateTime.now(),
      lastUpdated: DateTime.now(),
      severity: severity,
      source: 'HERE Technologies',
      sourceType: RoadAlertSourceType.providerReported,
    );
  }
}