import { api } from './request'
import { secureGet } from '@/utils/secure-storage'

type EventName =
  | 'page_view'
  | 'login'
  | 'bind_phone'
  | 'health_data_input'
  | 'health_trend_view'
  | 'appointment_create'
  | 'appointment_detail'
  | 'followup_submit'
  | 'report_view'
  | 'article_view'
  | 'article_share'
  | 'medication_add'
  | 'family_add'
  | 'profile_edit'

interface AnalyticsEvent {
  event: EventName | string
  properties?: Record<string, unknown>
  timestamp: number
  userId?: string
  patientId?: string
}

const QUEUE_KEY = 'analytics_queue'
const MAX_QUEUE_SIZE = 50

function getQueue(): AnalyticsEvent[] {
  return uni.getStorageSync(QUEUE_KEY) || []
}

function setQueue(queue: AnalyticsEvent[]): void {
  uni.setStorageSync(QUEUE_KEY, queue.slice(-MAX_QUEUE_SIZE))
}

export function trackEvent(event: EventName | string, properties?: Record<string, unknown>): void {
  let userId: string | undefined
  try {
    const raw = secureGet('user_data')
    userId = raw ? JSON.parse(raw).id : undefined
  } catch { /* ignore */ }
  const patientId = uni.getStorageSync('current_patient_id')

  const evt: AnalyticsEvent = { event, properties, timestamp: Date.now(), userId, patientId }
  const queue = getQueue()
  queue.push(evt)
  setQueue(queue)
}

export function trackPageView(pageName: string, properties?: Record<string, unknown>): void {
  trackEvent('page_view', { page: pageName, ...properties })
}

export async function flushEvents(): Promise<void> {
  const queue = getQueue()
  if (queue.length === 0) return
  const batch = queue.slice()
  setQueue([])
  try {
    await api.post('/analytics/batch', { events: batch })
  } catch {
    const current = getQueue()
    setQueue([...batch.slice(-MAX_QUEUE_SIZE + current.length), ...current])
  }
}

export function getQueueSize(): number {
  return getQueue().length
}