/**
 * Monitor 3: User Analytics Service
 * Tracks feature usage and user interactions
 */

import { apiClient } from './api/client';
import { logger } from '@/utils/logger';

export const analyticsService = {
  /**
   * Monitor 3: Record a user analytics event
   * Tracks feature usage and user interactions
   * @param eventName - Name of the event (e.g., 'feature_used', 'button_clicked')
   * @param payload - Optional event data (e.g., { feature: 'search', query: '...' })
   */
  recordEvent: async (eventName: string, payload?: Record<string, unknown>) => {
    try {
      // Send event to backend analytics endpoint
      await apiClient.post('/analytics/events', {
        event_name: eventName,
        payload: payload || {},
      });

      // Log in development for debugging
      if (import.meta.env.DEV) {
        logger.debug('[Analytics] Event recorded', {
          event_name: eventName,
          payload,
        });
      }
    } catch (error) {
      // Don't throw errors for analytics - fail silently to avoid disrupting user experience
      if (import.meta.env.DEV) {
        logger.warn('[Analytics] Failed to record event', {
          event_name: eventName,
          error: error instanceof Error ? error.message : String(error),
        });
      }
    }
  },

  getGlobalStats: async (range: string = '30d') => {
    try {
      const response = await apiClient.get<{ data?: Record<string, unknown> }>('/analytics', {
        params: { days: range.replace('d', '') }
      });

      const data = (response.data?.data ?? response.data) as Record<string, unknown> | undefined;
      if (!data || typeof data !== 'object') {
        return {};
      }

      return {
        total_tracks: (data.total_tracks as number | undefined) ?? 0,
        total_plays: (data.total_plays as number | undefined) ?? 0,
        total_revenue: (data.total_revenue as number | undefined) ?? 0,
        followers: (data.followers as number | undefined) ?? 0,
        profile_views: (data.profile_views as number | undefined) ?? 0,
        trends: (data.trends as Record<string, number> | undefined) ?? { plays: 0, revenue: 0, followers: 0, views: 0 },
        sparklines: (data.sparklines as Record<string, number[]> | undefined) ?? { plays: [0], revenue: [0], followers: [0], views: [0] },
      };
    } catch (error) {
      logger.error('[Analytics] Failed to fetch global stats', { error });
      throw error;
    }
  },

  getTopTracks: async (range: string = '30d') => {
    try {
      const response = await apiClient.get<{ data?: { tracks?: { top_tracks?: unknown[] } } }>('/analytics', {
        params: { days: range.replace('d', '') }
      });

      const data = response.data?.data ?? response.data;
      const topTracks = (data as Record<string, unknown>)?.tracks as { top_tracks?: Array<{ id?: string; title?: string; plays?: number; play_count?: number; change?: number; revenue?: number }> } | undefined;
      const tracks = topTracks?.top_tracks ?? [];

      return tracks.map((t) => ({
        id: t.id ?? '',
        title: t.title ?? '',
        plays: t.plays ?? t.play_count ?? 0,
        change: t.change ?? 0,
        revenue: t.revenue ?? 0,
      }));
    } catch (error) {
      logger.error('[Analytics] Failed to fetch top tracks', { error });
      throw error;
    }
  },

  getTrafficSources: async () => {
    try {
      const response = await apiClient.get<{ sources?: unknown[] }>('/analytics/traffic-sources');
      return (response.data?.sources ?? []) as unknown[];
    } catch (error) {
      logger.warn('[Analytics] Failed to fetch traffic sources', { error });
      return [];
    }
  },

  getCreatorStats: async (params?: { start_date?: string; end_date?: string; days?: number }) => {
    try {
      const searchParams = new URLSearchParams();
      if (params?.days != null) searchParams.set('days', String(params.days));
      if (params?.start_date) searchParams.set('start_date', params.start_date);
      if (params?.end_date) searchParams.set('end_date', params.end_date);
      const qs = searchParams.toString();
      const url = `/analytics/creator/stats${qs ? `?${qs}` : ''}`;
      const response = await apiClient.get<{
        data?: {
          total_plays?: number;
          unique_listeners?: number;
          average_completion_rate?: number;
          plays_by_day?: number[];
          period?: { start_date?: string; end_date?: string; days?: number };
        };
      }>(url);
      const data = (response.data?.data ?? response.data) as Record<string, unknown> | undefined;
      return data ?? {};
    } catch (error) {
      logger.error('[Analytics] Failed to fetch creator stats', { error });
      throw error;
    }
  },

  getDeviceBreakdown: async () => {
    try {
      const response = await apiClient.get<{ mobile?: number; desktop?: number }>('/analytics/device-breakdown');
      return {
        mobile: response.data?.mobile ?? 0,
        desktop: response.data?.desktop ?? 0,
      };
    } catch (error) {
      logger.warn('[Analytics] Failed to fetch device breakdown', { error });
      return { mobile: 0, desktop: 0 };
    }
  },
};