import apiClient from './api/client'

export interface Notification {
  id: string
  title: string
  message: string
  type: 'system' | 'user' | 'alert' | 'invoice' | 'payment'
  recipient: string
  status: 'sent' | 'delivered' | 'read' | 'unread'
  isRead: boolean
  createdAt: string
  sentAt?: string
  readAt?: string
}

export interface NotificationSettings {
  emailNotifications: boolean
  pushNotifications: boolean
  invoiceReminders: boolean
  paymentAlerts: boolean
  systemUpdates: boolean
}

class NotificationService {
  /**
   * Get all notifications for current user
   */
  async getNotifications(params?: {
    type?: string
    status?: string
    search?: string
  }): Promise<Notification[]> {
    const response = await apiClient.get<Notification[]>('/notifications', {
      params,
    })
    return response.data
  }

  /**
   * Get unread notification count
   */
  async getUnreadCount(): Promise<number> {
    const response = await apiClient.get<{ count: number }>('/notifications/unread-count')
    return response.data.count
  }

  /**
   * Mark notification as read
   */
  async markAsRead(id: string): Promise<void> {
    await apiClient.post(`/notifications/${id}/read`)
  }

  /**
   * Mark all notifications as read
   */
  async markAllAsRead(): Promise<void> {
    await apiClient.post('/notifications/read-all')
  }

  /**
   * Broadcast push, SMS, and/or email (Super Admin & Admin only)
   */
  async sendBroadcast(data: {
    title: string
    message: string
    channels: ('push' | 'sms' | 'email')[]
    audience?: 'all_end_users' | 'system_users_only' | 'everyone_with_access'
  }): Promise<{ id: string }> {
    const response = await apiClient.post<{ id: string }>(
      '/admin/notifications/broadcast',
      data,
    )
    return response.data
  }

  /**
   * Send notification (ADMIN only)
   */
  async sendNotification(data: {
    title: string
    message: string
    type: string
    recipient?: string
    recipientType?: 'user' | 'all'
  }): Promise<Notification> {
    const response = await apiClient.post<Notification>('/notifications/send', data)
    return response.data
  }

  /**
   * Subscribe to push notifications
   */
  async subscribeToPush(subscription: PushSubscription): Promise<void> {
    await apiClient.post('/notifications/subscribe', subscription)
  }

  /**
   * Unsubscribe from push notifications
   */
  async unsubscribeFromPush(endpoint: string): Promise<void> {
    await apiClient.delete(`/notifications/unsubscribe/${encodeURIComponent(endpoint)}`)
  }

  /**
   * Get notification settings
   */
  async getSettings(): Promise<NotificationSettings> {
    const response = await apiClient.get<NotificationSettings>('/notifications/settings')
    return response.data
  }

  /**
   * Update notification settings
   */
  async updateSettings(settings: Partial<NotificationSettings>): Promise<NotificationSettings> {
    const response = await apiClient.put<NotificationSettings>('/notifications/settings', settings)
    return response.data
  }

  /**
   * Send invoice reminder
   */
  async sendInvoiceReminder(invoiceId: string): Promise<void> {
    await apiClient.post(`/notifications/invoice/${invoiceId}/reminder`)
  }

  /**
   * Export notifications (creates CSV from current data)
   */
  async exportNotifications(notifications: Notification[]): Promise<Blob> {
    const csvContent = [
      ['ID', 'Title', 'Message', 'Type', 'Status', 'Created Date', 'Read Date'],
      ...notifications.map(n => [
        n.id,
        n.title,
        n.message,
        n.type,
        n.status,
        n.createdAt,
        n.readAt || '-'
      ])
    ].map(row => row.join(',')).join('\n')

    return new Blob([csvContent], { type: 'text/csv;charset=utf-8;' })
  }
}

export const notificationService = new NotificationService()