import 'package:firebase_analytics/firebase_analytics.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';

/// Firebase Analytics service for tracking user events across the app.
///
/// Usage:
/// ```dart
/// // Log add to cart event
/// AnalyticsService.logAddToCart(
///   productId: 'SKU123',
///   productName: 'Gạch men 60x60',
///   price: 150000,
///   quantity: 2,
/// );
/// ```
class AnalyticsService {
  AnalyticsService._();

  static final FirebaseAnalytics _analytics = FirebaseAnalytics.instance;

  /// Get the analytics instance for NavigatorObserver
  static FirebaseAnalytics get instance => _analytics;

  /// Get the observer for automatic screen tracking in GoRouter
  static FirebaseAnalyticsObserver get observer => FirebaseAnalyticsObserver(
        analytics: _analytics,
        nameExtractor: (settings) {
          // GoRouter uses the path as the route name
          final name = settings.name;
          if (name != null && name.isNotEmpty && name != '/') {
            return name;
          }
          return settings.name ?? '/';
        },
        routeFilter: (route) => route is PageRoute,
      );

  /// Log screen view manually
  static Future<void> logScreenView({
    required String screenName,
    String? screenClass,
  }) async {
    try {
      await _analytics.logScreenView(
        screenName: screenName,
        screenClass: screenClass,
      );
      debugPrint('📊 Analytics: screen_view - $screenName');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  // ============================================================================
  // E-commerce Events
  // ============================================================================

  /// Log view item event - when user views product detail
  static Future<void> logViewItem({
    required String productId,
    required String productName,
    required double price,
    String? brand,
    String? category,
  }) async {
    try {
      await _analytics.logViewItem(
        currency: 'VND',
        value: price,
        items: [
          AnalyticsEventItem(
            itemId: productId,
            itemName: productName,
            price: price,
            itemBrand: brand,
            itemCategory: category,
          ),
        ],
      );
      debugPrint('📊 Analytics: view_item - $productName');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log add to cart event
  static Future<void> logAddToCart({
    required String productId,
    required String productName,
    required double price,
    required int quantity,
    String? brand,
  }) async {
    try {
      await _analytics.logAddToCart(
        currency: 'VND',
        value: price * quantity,
        items: [
          AnalyticsEventItem(
            itemId: productId,
            itemName: productName,
            price: price,
            quantity: quantity,
            itemBrand: brand,
          ),
        ],
      );
      debugPrint('📊 Analytics: add_to_cart - $productName x$quantity');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log remove from cart event
  static Future<void> logRemoveFromCart({
    required String productId,
    required String productName,
    required double price,
    required int quantity,
  }) async {
    try {
      await _analytics.logRemoveFromCart(
        currency: 'VND',
        value: price * quantity,
        items: [
          AnalyticsEventItem(
            itemId: productId,
            itemName: productName,
            price: price,
            quantity: quantity,
          ),
        ],
      );
      debugPrint('📊 Analytics: remove_from_cart - $productName');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log view cart event
  static Future<void> logViewCart({
    required double cartValue,
    required List<AnalyticsEventItem> items,
  }) async {
    try {
      await _analytics.logViewCart(
        currency: 'VND',
        value: cartValue,
        items: items,
      );
      debugPrint('📊 Analytics: view_cart - ${items.length} items');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log begin checkout event
  static Future<void> logBeginCheckout({
    required double value,
    required List<AnalyticsEventItem> items,
    String? coupon,
  }) async {
    try {
      await _analytics.logBeginCheckout(
        currency: 'VND',
        value: value,
        items: items,
        coupon: coupon,
      );
      debugPrint('📊 Analytics: begin_checkout - $value VND');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log purchase event - when order is completed
  static Future<void> logPurchase({
    required String orderId,
    required double value,
    required List<AnalyticsEventItem> items,
    double? shipping,
    double? tax,
    String? coupon,
  }) async {
    try {
      await _analytics.logPurchase(
        currency: 'VND',
        transactionId: orderId,
        value: value,
        items: items,
        shipping: shipping,
        tax: tax,
        coupon: coupon,
      );
      debugPrint('📊 Analytics: purchase - Order $orderId');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  // ============================================================================
  // Search & Discovery Events
  // ============================================================================

  /// Log search event
  static Future<void> logSearch({
    required String searchTerm,
  }) async {
    try {
      await _analytics.logSearch(searchTerm: searchTerm);
      debugPrint('📊 Analytics: search - $searchTerm');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log select item event - when user taps on a product in list
  static Future<void> logSelectItem({
    required String productId,
    required String productName,
    String? listName,
  }) async {
    try {
      await _analytics.logSelectItem(
        itemListName: listName,
        items: [
          AnalyticsEventItem(
            itemId: productId,
            itemName: productName,
          ),
        ],
      );
      debugPrint('📊 Analytics: select_item - $productName');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  // ============================================================================
  // Loyalty & Rewards Events
  // ============================================================================

  /// Log earn points event
  static Future<void> logEarnPoints({
    required int points,
    required String source,
  }) async {
    try {
      await _analytics.logEarnVirtualCurrency(
        virtualCurrencyName: 'loyalty_points',
        value: points.toDouble(),
      );
      debugPrint('📊 Analytics: earn_points - $points from $source');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log spend points event - when user redeems points
  static Future<void> logSpendPoints({
    required int points,
    required String itemName,
  }) async {
    try {
      await _analytics.logSpendVirtualCurrency(
        virtualCurrencyName: 'loyalty_points',
        value: points.toDouble(),
        itemName: itemName,
      );
      debugPrint('📊 Analytics: spend_points - $points for $itemName');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  // ============================================================================
  // User Events
  // ============================================================================

  /// Log login event
  static Future<void> logLogin({
    String? method,
  }) async {
    try {
      await _analytics.logLogin(loginMethod: method ?? 'phone');
      debugPrint('📊 Analytics: login - $method');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log sign up event
  static Future<void> logSignUp({
    String? method,
  }) async {
    try {
      await _analytics.logSignUp(signUpMethod: method ?? 'phone');
      debugPrint('📊 Analytics: sign_up - $method');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Log share event
  static Future<void> logShare({
    required String contentType,
    required String itemId,
    String? method,
  }) async {
    try {
      await _analytics.logShare(
        contentType: contentType,
        itemId: itemId,
        method: method ?? 'unknown',
      );
      debugPrint('📊 Analytics: share - $contentType $itemId');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  // ============================================================================
  // Custom Events
  // ============================================================================

  /// Log custom event
  static Future<void> logEvent({
    required String name,
    Map<String, Object>? parameters,
  }) async {
    try {
      await _analytics.logEvent(name: name, parameters: parameters);
      debugPrint('📊 Analytics: $name');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Set user ID for analytics
  static Future<void> setUserId(String? userId) async {
    try {
      await _analytics.setUserId(id: userId);
      debugPrint('📊 Analytics: setUserId - $userId');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }

  /// Set user property
  static Future<void> setUserProperty({
    required String name,
    required String? value,
  }) async {
    try {
      await _analytics.setUserProperty(name: name, value: value);
      debugPrint('📊 Analytics: setUserProperty - $name: $value');
    } catch (e) {
      debugPrint('📊 Analytics error: $e');
    }
  }
}