import { computed, ref } from 'vue'
import { useApi } from '~/composables/useApi'
import { useToast } from '~/composables/useToast'

type GuardLabels = {
  singular: string
  plural: string
  verifying: string
}

type GuardConfig = {
  endpoint: string
  filterKey: string
  labels: GuardLabels
}

const extractTotal = (payload: any, fallbackLength: number) => {
  if (typeof payload?.totalItems === 'number') {
    return payload.totalItems
  }
  if (typeof payload?.['hydra:totalItems'] === 'number') {
    return payload['hydra:totalItems']
  }
  if (Array.isArray(payload?.member)) {
    return payload.member.length
  }
  if (Array.isArray(payload?.['hydra:member'])) {
    return payload['hydra:member'].length
  }
  return fallbackLength
}

export function useCategoryEditGuard (config: GuardConfig) {
  const { get } = useApi()
  const { showInfo } = useToast()

  const linkedCount = ref(0)
  const linkedLoading = ref(false)

  const loadLinkedCount = async (modelTypeId: string) => {
    linkedLoading.value = true
    try {
      const params = new URLSearchParams()
      params.set('itemsPerPage', '1')
      params.set(config.filterKey, `/api/model_types/${modelTypeId}`)

      const result = await get(`${config.endpoint}?${params.toString()}`)
      if (!result.success) {
        linkedCount.value = 0
        return
      }

      const fallbackLength = Array.isArray(result.data?.member)
        ? result.data.member.length
        : Array.isArray(result.data?.['hydra:member'])
          ? result.data['hydra:member'].length
          : 0

      linkedCount.value = extractTotal(result.data, fallbackLength)
    } catch (error) {
      linkedCount.value = 0
    } finally {
      linkedLoading.value = false
    }
  }

  const isRestrictedMode = computed(
    () => !linkedLoading.value && linkedCount.value > 0,
  )

  const isSubmitBlocked = computed(
    () => linkedLoading.value,
  )

  const restrictedModeMessage = computed(() => {
    if (linkedLoading.value) {
      return config.labels.verifying
    }
    if (linkedCount.value <= 0) {
      return ''
    }
    if (linkedCount.value === 1) {
      return `Mode restreint : 1 ${config.labels.singular} est déjà lié à cette catégorie. Vous pouvez ajouter de nouveaux champs personnalisés, mais pas modifier ou supprimer les existants.`
    }
    return `Mode restreint : ${linkedCount.value} ${config.labels.plural} sont déjà liés à cette catégorie. Vous pouvez ajouter de nouveaux champs personnalisés, mais pas modifier ou supprimer les existants.`
  })

  const submitBlockMessage = computed(() => {
    if (linkedLoading.value) {
      return config.labels.verifying
    }
    return ''
  })

  const guardSubmitOrNotify = () => {
    if (!isSubmitBlocked.value) {
      return false
    }
    showInfo(submitBlockMessage.value || 'Veuillez patienter...')
    return true
  }

  return {
    linkedCount,
    linkedLoading,
    isRestrictedMode,
    isSubmitBlocked,
    restrictedModeMessage,
    submitBlockMessage,
    loadLinkedCount,
    guardSubmitOrNotify,
  }
}