import { ref } from 'vue'

export const useNotificationLogs = () => {
  // Use Nuxt's useFetch instead of $fetch
  const config = useRuntimeConfig()
  
  // Logs data state
  const logs = ref([])
  const loading = ref(false)
  const error = ref(null)
  const pagination = ref({
    page: 1,
    limit: 10,
    total: 0,
    pages: 1
  })
  const summaryStats = ref({
    totalLogs: 0,
    failedDeliveries: 0,
    successfulDeliveries: 0,
    successRate: 0
  })
  
  // Filters state
  const filters = ref({
    startDate: null,
    endDate: null,
    action: null,
    channel: null,
    status: null,
    actor: '',
    keyword: ''
  })
  
  // Analytics state
  const analyticsData = ref(null)
  const analyticsLoading = ref(false)
  const analyticsError = ref(null)
  
  // Monitoring state
  const monitoringData = ref(null)
  const monitoringLoading = ref(false)
  const monitoringError = ref(null)
  
  // Fetch logs with filters and pagination
  const fetchLogs = async () => {
    try {
      loading.value = true
      error.value = null
      
      // Build query parameters
      const queryParams = new URLSearchParams()
      queryParams.append('page', pagination.value.page)
      queryParams.append('limit', pagination.value.limit)
      
      // Add filters if they exist
      if (filters.value.startDate) queryParams.append('startDate', filters.value.startDate)
      if (filters.value.endDate) queryParams.append('endDate', filters.value.endDate)
      if (filters.value.action) queryParams.append('action', filters.value.action)
      if (filters.value.channel) queryParams.append('channel', filters.value.channel)
      if (filters.value.status) queryParams.append('status', filters.value.status)
      if (filters.value.actor) queryParams.append('actor', filters.value.actor)
      if (filters.value.keyword) queryParams.append('keyword', filters.value.keyword)
      
      // Make API call with useFetch
      const { data, error: fetchError } = await useFetch(`/api/notifications/logs`, {
        method: 'GET',
        params: {
          page: pagination.value.page,
          limit: pagination.value.limit,
          ...filters.value
        }
      })
      
      if (fetchError.value) {
        throw new Error(fetchError.value.message || 'Failed to fetch logs');
      }
      
      if (data.value && data.value.body && data.value.body.success) {
        logs.value = data.value.body.data.logs || [];
        pagination.value = data.value.body.data.pagination || pagination.value;
        
        // Ensure summary stats are properly assigned
        if (data.value.body.data.summary) {
          summaryStats.value = {
            totalLogs: data.value.body.data.summary.totalLogs || 0,
            failedDeliveries: data.value.body.data.summary.failedDeliveries || 0,
            successfulDeliveries: data.value.body.data.summary.successfulDeliveries || 0,
            successRate: data.value.body.data.summary.successRate || 0
          };
        }
        
        console.log('Logs fetched successfully:', {
          logsCount: logs.value.length,
          pagination: pagination.value,
          summaryStats: summaryStats.value
        });
      } else {
        throw new Error('Failed to fetch logs: ' + (data.value?.body?.message || 'Unknown error'))
      }
    } catch (err) {
      error.value = err.message || 'An error occurred'
      console.error('Error fetching logs:', err)
    } finally {
      loading.value = false
    }
  }
  
  // Get a specific log by ID
  const getLogById = async (id) => {
    try {
      loading.value = true
      error.value = null
      
      // Make API call
      const { data } = await useFetch(`/api/notifications/logs/${id}`, {
        method: 'GET'
      })
      
      if (data.value && data.value.body && data.value.body.success) {
        return data.value.body.data
      } else {
        throw new Error('Failed to fetch log details')
      }
    } catch (err) {
      error.value = err.message || 'An error occurred'
      console.error('Error fetching log details:', err)
      return null
    } finally {
      loading.value = false
    }
  }
  
  // Update filters and fetch logs
  const applyFilters = async (newFilters) => {
    filters.value = { ...filters.value, ...newFilters }
    pagination.value.page = 1 // Reset to first page when filters change
    await fetchLogs()
  }
  
  // Clear all filters
  const clearFilters = async () => {
    filters.value = {
      startDate: null,
      endDate: null,
      action: null,
      channel: null,
      status: null,
      actor: '',
      keyword: ''
    }
    pagination.value.page = 1
    await fetchLogs()
  }
  
  // Change page
  const changePage = async (page) => {
    pagination.value.page = page
    await fetchLogs()
  }
  
  // Fetch analytics data
  const fetchAnalytics = async (period = '7d', channel = 'all') => {
    try {
      analyticsLoading.value = true
      analyticsError.value = null
      
      // Make API call
      const { data } = await useFetch(`/api/notifications/logs/analytics`, {
        method: 'GET',
        params: {
          period,
          channel
        }
      })
      
      if (data.value && data.value.body && data.value.body.success) {
        analyticsData.value = data.value.body.data
      } else {
        throw new Error('Failed to fetch analytics data')
      }
    } catch (err) {
      analyticsError.value = err.message || 'An error occurred'
      console.error('Error fetching analytics data:', err)
    } finally {
      analyticsLoading.value = false
    }
  }
  
  // Fetch monitoring data
  const fetchMonitoringData = async () => {
    try {
      monitoringLoading.value = true
      monitoringError.value = null
      
      // Make API call
      const { data } = await useFetch('/api/notifications/logs/monitoring', {
        method: 'GET'
      })
      
      if (data.value && data.value.body && data.value.body.success) {
        monitoringData.value = data.value.body.data
      } else {
        throw new Error('Failed to fetch monitoring data')
      }
    } catch (err) {
      monitoringError.value = err.message || 'An error occurred'
      console.error('Error fetching monitoring data:', err)
    } finally {
      monitoringLoading.value = false
    }
  }
  
  // Format date for display
  const formatDate = (date, includeTime = false) => {
    if (!date) return ''
    const options = { year: 'numeric', month: 'short', day: 'numeric' }
    if (includeTime) {
      options.hour = '2-digit'
      options.minute = '2-digit'
    }
    return new Date(date).toLocaleDateString(undefined, options)
  }
  
  // Format time ago (e.g., "2 minutes ago")
  const formatTimeAgo = (timestamp) => {
    const now = new Date()
    const time = new Date(timestamp)
    const diffInMinutes = Math.floor((now - time) / (1000 * 60))
  
    if (diffInMinutes < 1) return "Just now"
    if (diffInMinutes < 60) return `${diffInMinutes} minutes ago`
    if (diffInMinutes < 1440) return `${Math.floor(diffInMinutes / 60)} hours ago`
    return `${Math.floor(diffInMinutes / 1440)} days ago`
  }
  
  // Get available actions for filters
  const availableActions = [
    { label: 'All Actions', value: null },
    { label: 'Notification Created', value: 'Notification Created' },
    { label: 'Notification Sent', value: 'Notification Sent' },
    { label: 'Delivery Attempted', value: 'Delivery Attempted' },
    { label: 'Delivery Failed', value: 'Delivery Failed' },
    { label: 'Notification Opened', value: 'Notification Opened' },
    { label: 'Template Updated', value: 'Template Updated' },
    { label: 'Notification Queued', value: 'Notification Queued' },
  ]
  
  // Get available channels for filters
  const availableChannels = [
    { label: 'All Channels', value: null },
    { label: 'Email', value: 'Email' },
    { label: 'SMS', value: 'SMS' },
    { label: 'Push Notification', value: 'Push Notification' },
    { label: 'Webhook', value: 'Webhook' }
  ]
  
  // Get available statuses for filters
  const availableStatuses = [
    { label: 'All Statuses', value: null },
    { label: 'Sent', value: 'Sent' },
    { label: 'Failed', value: 'Failed' },
    { label: 'Bounced', value: 'Bounced' },
    { label: 'Opened', value: 'Opened' },
    { label: 'Queued', value: 'Queued' },
    { label: 'Created', value: 'Created' },
    { label: 'Updated', value: 'Updated' }
  ]

  return {
    // State
    logs,
    loading,
    error,
    pagination,
    summaryStats,
    filters,
    analyticsData,
    analyticsLoading,
    analyticsError,
    monitoringData,
    monitoringLoading,
    monitoringError,
    
    // Methods
    fetchLogs,
    getLogById,
    applyFilters,
    clearFilters,
    changePage,
    fetchAnalytics,
    fetchMonitoringData,
    formatDate,
    formatTimeAgo,
    
    // Filter options
    availableActions,
    availableChannels,
    availableStatuses
  }
}