import { computed, ref } from 'vue'
import { defineStore } from 'pinia'
import { getMyUnreadNotificationCount } from '../api/notifications'

export const useNotificationsStore = defineStore('client-notifications', () => {
  const unreadCount = ref<number | null>(null)
  const loading = ref(false)
  const errorMessage = ref('')

  const hasUnread = computed(() => (unreadCount.value ?? 0) > 0)

  let pending: Promise<void> | null = null

  async function refreshUnreadCount(afterMutation = false): Promise<void> {
    if (pending) {
      if (!afterMutation) return pending
      await pending
      return refreshUnreadCount()
    }
    pending = loadUnreadCount().finally(() => { pending = null })
    return pending
  }

  async function loadUnreadCount() {
    loading.value = true
    errorMessage.value = ''
    try {
      unreadCount.value = await getMyUnreadNotificationCount()
    } catch (error) {
      unreadCount.value = null
      errorMessage.value = error instanceof Error ? error.message : '未读数量加载失败'
    } finally {
      loading.value = false
    }
  }

  return { unreadCount, hasUnread, loading, errorMessage, refreshUnreadCount }
})