/**
 * Notification Store – Polls unread count and notifications from the API.
 */
import { defineStore } from 'pinia'
import { apiFetch } from '../services/api'

export interface NotificationItem {
  id: string
  type: string       // "task_assigned", "task_review", "task_blocked"
  title: string
  message: string | null
  forUser: string
  taskId: string | null
  isRead: boolean
  createdAt: string
}

export interface UnreadCount {
  count: number
}

export const useNotificationStore = defineStore('notifications', {
  state: () => ({
    notifications: [] as NotificationItem[],
    unreadCount: 0,
    loading: false,
    error: null as string | null,
    countRefreshInterval: null as ReturnType<typeof setInterval> | null,
    listRefreshInterval: null as ReturnType<typeof setInterval> | null,
  }),

  actions: {
    async fetchNotifications(forUser = 'bao', limit = 50, unreadOnly = false) {
      this.loading = true
      try {
        const params = new URLSearchParams({ forUser, limit: String(limit), unreadOnly: String(unreadOnly) })
        const res = await apiFetch(`/api/dashboard/notifications?${params}`)
        if (!res.ok) throw new Error(`HTTP ${res.status}`)
        this.notifications = await res.json()
        this.error = null
      } catch (err) {
        console.warn('[NotificationStore] fetchNotifications failed', err)
        this.error = 'Notifications could not be loaded'
      } finally {
        this.loading = false
      }
    },

    async fetchUnreadCount(forUser = 'bao') {
      try {
        const params = new URLSearchParams({ forUser })
        const res = await apiFetch(`/api/dashboard/notifications/unread-count?${params}`)
        if (!res.ok) throw new Error(`HTTP ${res.status}`)
        const data: UnreadCount = await res.json()
        this.unreadCount = data.count
      } catch (err) {
        console.warn('[NotificationStore] fetchUnreadCount failed', err)
      }
    },

    async markAsRead(id: string) {
      try {
        const res = await apiFetch(`/api/dashboard/notifications/${id}/read`, { method: 'PATCH' })
        if (!res.ok) throw new Error(`HTTP ${res.status}`)
        // Update local state
        const n = this.notifications.find(n => n.id === id)
        if (n) n.isRead = true
        this.unreadCount = Math.max(0, this.unreadCount - 1)
      } catch (err) {
        console.warn('[NotificationStore] markAsRead failed', err)
      }
    },

    async markAllAsRead(forUser = 'bao') {
      try {
        const params = new URLSearchParams({ forUser })
        const res = await apiFetch(`/api/dashboard/notifications/read-all?${params}`, { method: 'PATCH' })
        if (!res.ok) throw new Error(`HTTP ${res.status}`)
        this.notifications.forEach(n => { n.isRead = true })
        this.unreadCount = 0
      } catch (err) {
        console.warn('[NotificationStore] markAllAsRead failed', err)
      }
    },

    startPolling(forUser = 'bao') {
      if (!this.countRefreshInterval) {
        this.fetchUnreadCount(forUser)
        this.countRefreshInterval = setInterval(() => {
          this.fetchUnreadCount(forUser)
        }, 30000)
      }
    },

    stopPolling() {
      if (this.countRefreshInterval) {
        clearInterval(this.countRefreshInterval)
        this.countRefreshInterval = null
      }
      if (this.listRefreshInterval) {
        clearInterval(this.listRefreshInterval)
        this.listRefreshInterval = null
      }
    },

    startListPolling(forUser = 'bao') {
      if (!this.listRefreshInterval) {
        this.fetchNotifications(forUser)
        this.listRefreshInterval = setInterval(() => {
          this.fetchNotifications(forUser)
        }, 30000)
      }
    },

    stopListPolling() {
      if (this.listRefreshInterval) {
        clearInterval(this.listRefreshInterval)
        this.listRefreshInterval = null
      }
    },
  },
})