import { useState, useEffect, useCallback } from 'react'
import { notificationService, loadStoredNotifications, saveNotifications, markNotificationAsRead, markAllAsRead, deleteNotification } from '@/lib/notifications'
import type { Notification } from '@/types/notifications'

export function useNotifications(userPubkey: string | null) {
  const [notifications, setNotifications] = useState<Notification[]>([])
  const [loading, setLoading] = useState(true)

  // Load stored notifications on mount
  useEffect(() => {
    if (!userPubkey) {
      setNotifications([])
      setLoading(false)
      return
    }

    const stored = loadStoredNotifications(userPubkey)
    setNotifications(stored)
    setLoading(false)
  }, [userPubkey])

  // Subscribe to new notifications
  useEffect(() => {
    if (!userPubkey) {
      return
    }

    const unsubscribe = notificationService.subscribeToPayments(userPubkey, (newNotification) => {
      setNotifications((prev) => {
        // Check if notification already exists
        if (prev.some((n) => n.id === newNotification.id)) {
          return prev
        }

        // Add new notification at the beginning
        const updated = [newNotification, ...prev]

        // Keep only last 100 notifications
        const trimmed = updated.slice(0, 100)

        // Save to localStorage
        saveNotifications(userPubkey, trimmed)

        return trimmed
      })
    })

    return () => {
      unsubscribe()
    }
  }, [userPubkey])

  const unreadCount = notifications.filter((n) => !n.read).length

  const markAsRead = useCallback(
    (notificationId: string) => {
      if (!userPubkey) return

      setNotifications((prev) => markNotificationAsRead(userPubkey, notificationId, prev))
    },
    [userPubkey]
  )

  const markAllAsReadHandler = useCallback(() => {
    if (!userPubkey) return

    setNotifications((prev) => markAllAsRead(userPubkey, prev))
  }, [userPubkey])

  const deleteNotificationHandler = useCallback(
    (notificationId: string) => {
      if (!userPubkey) return

      setNotifications((prev) => deleteNotification(userPubkey, notificationId, prev))
    },
    [userPubkey]
  )

  return {
    notifications,
    unreadCount,
    loading,
    markAsRead,
    markAllAsRead: markAllAsReadHandler,
    deleteNotification: deleteNotificationHandler,
  }
}