import { computed, onMounted, reactive, ref, watch } from 'vue'
import { useRouter } from '#imports'
import { useComponentTypes } from '~/composables/useComponentTypes'
import { useComposants } from '~/composables/useComposants'
import { usePieceTypes } from '~/composables/usePieceTypes'
import { useProductTypes } from '~/composables/useProductTypes'
import { usePieces } from '~/composables/usePieces'
import { useProducts } from '~/composables/useProducts'
import { useCustomFields } from '~/composables/useCustomFields'
import { useApi } from '~/composables/useApi'
import { useToast } from '~/composables/useToast'
import { extractRelationId } from '~/shared/apiRelations'
import { useDocuments } from '~/composables/useDocuments'
import { useConstructeurs } from '~/composables/useConstructeurs'
import { useComponentHistory } from '~/composables/useComponentHistory'
import { formatStructurePreview, normalizeStructureForEditor } from '~/shared/modelUtils'
import { uniqueConstructeurIds } from '~/shared/constructeurUtils'
import {
  getStructurePieces,
  getStructureProducts,
  resolvePieceLabel as _resolvePieceLabel,
  resolveProductLabel as _resolveProductLabel,
  resolveSubcomponentLabel,
  fetchModelTypeNames,
  buildTypeLabelMap,
} from '~/shared/utils/structureDisplayUtils'
import type { ComponentModelStructure } from '~/shared/types/inventory'
import type { ModelType } from '~/services/modelTypes'
import { canPreviewDocument } from '~/utils/documentPreview'
import {
  type CustomFieldInput,
  buildCustomFieldInputs,
  requiredCustomFieldsFilled as _requiredCustomFieldsFilled,
  saveCustomFieldValues as _saveCustomFieldValues,
} from '~/shared/utils/customFieldFormUtils'
import { collectStructureSelections } from '~/shared/utils/structureSelectionUtils'

interface ComponentCatalogType extends ModelType {
  structure: ComponentModelStructure | null
  customFields?: Array<Record<string, any>>
}

const historyFieldLabels: Record<string, string> = {
  name: 'Nom',
  reference: 'Référence',
  prix: 'Prix',
  structure: 'Structure',
  typeComposant: 'Catégorie',
  product: 'Produit lié',
  constructeurIds: 'Fournisseurs',
}

export function useComponentEdit(componentId: string) {
  const { canEdit } = usePermissions()
  const router = useRouter()
  const { get, patch } = useApi()
  const { componentTypes, loadComponentTypes } = useComponentTypes()
  const { pieceTypes, loadPieceTypes } = usePieceTypes()
  const { productTypes, loadProductTypes } = useProductTypes()
  const { updateComposant, composants: componentCatalogRef } = useComposants()
  const { pieces } = usePieces()
  const { products } = useProducts()
  const { ensureConstructeurs } = useConstructeurs()
  const { upsertCustomFieldValue, updateCustomFieldValue } = useCustomFields()
  const toast = useToast()
  const { loadDocumentsByComponent, uploadDocuments, deleteDocument } = useDocuments()
  const {
    history,
    loading: historyLoading,
    error: historyError,
    loadHistory,
  } = useComponentHistory()

  const component = ref<any | null>(null)
  const loading = ref(true)
  const saving = ref(false)
  const selectedFiles = ref<File[]>([])
  const uploadingDocuments = ref(false)
  const loadingDocuments = ref(false)
  const componentDocuments = ref<any[]>([])
  const previewDocument = ref<any | null>(null)
  const previewVisible = ref(false)

  const selectedTypeId = ref<string>('')
  const editionForm = reactive({
    name: '' as string,
    description: '' as string,
    reference: '' as string,
    constructeurIds: [] as string[],
    prix: '' as string,
  })

  const customFieldInputs = ref<CustomFieldInput[]>([])
  const fetchedPieceTypeMap = ref<Record<string, string>>({})
  const pieceTypeLabelMap = computed(() =>
    buildTypeLabelMap(pieceTypes.value, fetchedPieceTypeMap.value),
  )
  const fetchedProductTypeMap = ref<Record<string, string>>({})
  const productTypeLabelMap = computed(() =>
    buildTypeLabelMap(productTypes.value, fetchedProductTypeMap.value),
  )
  const pieceCatalogMap = computed(() =>
    new Map(
      (pieces.value || [])
        .filter((item: any) => item?.id)
        .map((item: any) => [String(item.id), item]),
    ),
  )
  const productCatalogMap = computed(() =>
    new Map(
      (products.value || [])
        .filter((item: any) => item?.id)
        .map((item: any) => [String(item.id), item]),
    ),
  )
  const componentCatalogMap = computed(() =>
    new Map(
      (componentCatalogRef.value || [])
        .filter((item: any) => item?.id)
        .map((item: any) => [String(item.id), item]),
    ),
  )

  const openPreview = (doc: any) => {
    if (!doc || !canPreviewDocument(doc)) {
      return
    }
    previewDocument.value = doc
    previewVisible.value = true
  }

  const closePreview = () => {
    previewVisible.value = false
    previewDocument.value = null
  }

  const removeDocument = async (documentId: string | number | null | undefined) => {
    if (!documentId) {
      return
    }
    const result = await deleteDocument(documentId, { updateStore: false })
    if (result.success) {
      componentDocuments.value = componentDocuments.value.filter((doc) => doc.id !== documentId)
    }
  }

  const refreshDocuments = async () => {
    if (!component.value?.id) {
      componentDocuments.value = []
      return
    }
    loadingDocuments.value = true
    try {
      const result = await loadDocumentsByComponent(component.value.id, { updateStore: false })
      if (result.success) {
        componentDocuments.value = Array.isArray(result.data) ? result.data : result.data ? [result.data] : []
      }
    }
    finally {
      loadingDocuments.value = false
    }
  }

  const handleFilesAdded = async (files: File[]) => {
    if (!files?.length || !component.value?.id) {
      return
    }
    uploadingDocuments.value = true
    try {
      const result = await uploadDocuments(
        {
          files,
          context: { composantId: component.value.id },
        },
        { updateStore: false },
      )
      if (result.success) {
        selectedFiles.value = []
        await refreshDocuments()
      }
    }
    finally {
      uploadingDocuments.value = false
    }
  }

  const componentTypeList = computed<ComponentCatalogType[]>(() =>
    (componentTypes.value || [])
      .filter((item: any) => item?.category === 'COMPONENT') as ComponentCatalogType[],
  )

  const selectedType = computed(() => {
    if (!selectedTypeId.value) {
      return null
    }
    return componentTypeList.value.find((type) => type.id === selectedTypeId.value) ?? null
  })

  const selectedTypeStructure = computed<ComponentModelStructure | null>(() => {
    const structure = selectedType.value?.structure ?? null
    return structure ? normalizeStructureForEditor(structure) : null
  })

  const refreshCustomFieldInputs = (
    structureOverride?: ComponentModelStructure | null,
    valuesOverride?: any[] | null,
  ) => {
    const structure = structureOverride ?? selectedTypeStructure.value ?? null
    const values = valuesOverride ?? component.value?.customFieldValues ?? null
    customFieldInputs.value = buildCustomFieldInputs(structure, values)
  }

  const requiredCustomFieldsFilled = computed(() =>
    _requiredCustomFieldsFilled(customFieldInputs.value),
  )

  const canSubmit = computed(() => Boolean(
    canEdit.value
    && component.value
    && editionForm.name
    && requiredCustomFieldsFilled.value
    && !saving.value,
  ))

  const fetchComponent = async () => {
    if (!componentId || typeof componentId !== 'string') {
      component.value = null
      componentDocuments.value = []
      return
    }
    const result = await get(`/composants/${componentId}`)
    if (result.success) {
      component.value = result.data
      componentDocuments.value = Array.isArray(result.data?.documents) ? result.data.documents : []

      const customValues = Array.isArray(result.data?.customFieldValues) ? result.data.customFieldValues : []
      refreshCustomFieldInputs(undefined, customValues)

      loadHistory(result.data.id).catch(() => {})
    }
    else {
      component.value = null
      componentDocuments.value = []
    }
  }

  const resolvePieceLabel = (piece: Record<string, any>) =>
    _resolvePieceLabel(piece, pieceTypeLabelMap.value)

  const resolveProductLabel = (product: Record<string, any>) =>
    _resolveProductLabel(product, productTypeLabelMap.value)

  const structureSelections = computed(() => {
    const selections = collectStructureSelections(
      component.value?.structure,
      {
        pieceCatalogMap: pieceCatalogMap.value,
        productCatalogMap: productCatalogMap.value,
        componentCatalogMap: componentCatalogMap.value,
      },
      { resolvePieceLabel, resolveProductLabel, resolveSubcomponentLabel },
    )
    const total
      = selections.pieces.length + selections.products.length + selections.components.length
    return {
      ...selections,
      total,
      hasAny: total > 0,
    }
  })

  // --- Slot selection entries (for selectors) ---

  const pieceSlotEntries = computed(() => {
    const structure = component.value?.structure
    if (!structure?.pieces) return []
    return (structure.pieces as any[]).map((slot: any, i: number) => ({
      slotId: slot.slotId,
      typePieceId: slot.typePieceId,
      selectedPieceId: slot.selectedPieceId ?? null,
      quantity: slot.quantity ?? 1,
      position: slot.position ?? i,
      label: pieceTypeLabelMap.value[slot.typePieceId] || `Pièce #${i + 1}`,
    }))
  })

  const productSlotEntries = computed(() => {
    const structure = component.value?.structure
    if (!structure?.products) return []
    return (structure.products as any[]).map((slot: any, i: number) => ({
      slotId: slot.slotId,
      typeProductId: slot.typeProductId,
      selectedProductId: slot.selectedProductId ?? null,
      familyCode: slot.familyCode,
      position: slot.position ?? i,
      label: productTypeLabelMap.value[slot.typeProductId] || `Produit #${i + 1}`,
    }))
  })

  const subcomponentSlotEntries = computed(() => {
    const structure = component.value?.structure
    if (!structure?.subcomponents) return []
    return (structure.subcomponents as any[]).map((slot: any, i: number) => ({
      slotId: slot.slotId,
      typeComposantId: slot.typeComposantId,
      selectedComponentId: slot.selectedComponentId ?? null,
      alias: slot.alias,
      familyCode: slot.familyCode,
      position: slot.position ?? i,
      label: slot.alias || `Sous-composant #${i + 1}`,
    }))
  })

  const savePieceSlotSelection = async (slotId: string, selectedPieceId: string | null) => {
    const result = await patch(`/composant-piece-slots/${slotId}`, { selectedPieceId })
    if (result.success) {
      const structure = component.value?.structure
      if (structure?.pieces) {
        const slot = (structure.pieces as any[]).find((s: any) => s.slotId === slotId)
        if (slot) slot.selectedPieceId = selectedPieceId
      }
      toast.showSuccess('Pièce mise à jour')
    }
  }

  const saveProductSlotSelection = async (slotId: string, selectedProductId: string | null) => {
    const result = await patch(`/composant-product-slots/${slotId}`, { selectedProductId })
    if (result.success) {
      const structure = component.value?.structure
      if (structure?.products) {
        const slot = (structure.products as any[]).find((s: any) => s.slotId === slotId)
        if (slot) slot.selectedProductId = selectedProductId
      }
      toast.showSuccess('Produit mis à jour')
    }
  }

  const saveSubcomponentSlotSelection = async (slotId: string, selectedComposantId: string | null) => {
    const result = await patch(`/composant-subcomponent-slots/${slotId}`, { selectedComposantId })
    if (result.success) {
      const structure = component.value?.structure
      if (structure?.subcomponents) {
        const slot = (structure.subcomponents as any[]).find((s: any) => s.slotId === slotId)
        if (slot) slot.selectedComponentId = selectedComposantId
      }
      toast.showSuccess('Sous-composant mis à jour')
    }
  }

  const saveSlotQuantity = async (slotId: string, quantity: number) => {
    if (!slotId || quantity < 1) return
    const result = await patch(`/composant-piece-slots/${slotId}`, { quantity: Math.max(1, quantity) })
    if (result.success) {
      const structure = component.value?.structure
      if (structure?.pieces) {
        const slot = (structure.pieces as any[]).find((s: any) => s.slotId === slotId)
        if (slot) slot.quantity = quantity
      }
      toast.showSuccess('Quantité mise à jour')
    }
  }

  const submitEdition = async () => {
    if (!component.value) {
      return
    }

    const rawPrice = typeof editionForm.prix === 'string'
      ? editionForm.prix.trim()
      : editionForm.prix === null || editionForm.prix === undefined
        ? ''
        : String(editionForm.prix).trim()

    const payload: Record<string, any> = {
      name: editionForm.name.trim(),
      description: editionForm.description.trim() || null,
    }

    const reference = editionForm.reference.trim()
    payload.reference = reference || null
    payload.constructeurIds = uniqueConstructeurIds(editionForm.constructeurIds)

    if (rawPrice) {
      const parsed = Number(rawPrice)
      if (!Number.isNaN(parsed)) {
        payload.prix = String(parsed)
      }
    }
    else {
      payload.prix = null
    }

    saving.value = true
    try {
      const result = await updateComposant(component.value.id, payload)
      if (result.success && result.data) {
        const updatedComponent = result.data as Record<string, any>
        await _saveCustomFieldValues(
          'composant',
          updatedComponent.id,
          [
            updatedComponent?.typeComposant?.structure?.customFields,
          ],
          { customFieldInputs, upsertCustomFieldValue, updateCustomFieldValue, toast },
        )
        toast.showSuccess('Composant mis à jour avec succès.')
      }
    }
    catch (error: any) {
      toast.showError(error?.message || 'Erreur lors de la mise à jour du composant')
    }
    finally {
      saving.value = false
    }
  }

  // --- Watchers ---

  const initialized = ref(false)

  watch(
    [component, selectedTypeStructure],
    ([currentComponent, currentStructure]) => {
      if (!currentComponent) {
        return
      }

      if (!initialized.value) {
        const resolvedTypeId = currentComponent.typeComposantId
          || extractRelationId(currentComponent.typeComposant)
          || ''
        if (resolvedTypeId && !currentComponent.typeComposantId) {
          currentComponent.typeComposantId = resolvedTypeId
        }
        selectedTypeId.value = resolvedTypeId

        editionForm.name = currentComponent.name || ''
        editionForm.description = currentComponent.description || ''
        editionForm.reference = currentComponent.reference || ''
        editionForm.constructeurIds = uniqueConstructeurIds(
          currentComponent,
          Array.isArray(currentComponent.constructeurs) ? currentComponent.constructeurs : [],
          currentComponent.constructeur ? [currentComponent.constructeur] : [],
        )
        editionForm.prix = currentComponent.prix !== null && currentComponent.prix !== undefined ? String(currentComponent.prix) : ''
        if (editionForm.constructeurIds.length) {
          void ensureConstructeurs(editionForm.constructeurIds)
        }

        initialized.value = true
      }

      refreshCustomFieldInputs(selectedTypeStructure.value ?? currentStructure, currentComponent.customFieldValues)
    },
    { immediate: true },
  )

  watch(
    selectedTypeStructure,
    (structure) => {
      const pieceIds = getStructurePieces(structure)
        .map((piece: any) => piece?.typePieceId)
        .filter((id: any): id is string => typeof id === 'string' && id.trim().length > 0)
      if (pieceIds.length) {
        fetchModelTypeNames(Array.from(new Set(pieceIds)), pieceTypeLabelMap.value, get)
          .then((additions) => {
            if (Object.keys(additions).length) {
              fetchedPieceTypeMap.value = { ...fetchedPieceTypeMap.value, ...additions }
            }
          })
          .catch(() => {})
      }

      const productIds = getStructureProducts(structure)
        .map((product: any) => product?.typeProductId)
        .filter((id: any): id is string => typeof id === 'string' && id.trim().length > 0)
      if (productIds.length) {
        fetchModelTypeNames(Array.from(new Set(productIds)), productTypeLabelMap.value, get)
          .then((additions) => {
            if (Object.keys(additions).length) {
              fetchedProductTypeMap.value = { ...fetchedProductTypeMap.value, ...additions }
            }
          })
          .catch(() => {})
      }
    },
    { immediate: true },
  )

  // --- Lifecycle ---

  onMounted(async () => {
    await Promise.allSettled([
      loadComponentTypes(),
      loadPieceTypes(),
      loadProductTypes(),
      fetchComponent(),
    ])
    loading.value = false
  })

  return {
    // State
    component,
    loading,
    saving,
    selectedFiles,
    uploadingDocuments,
    loadingDocuments,
    componentDocuments,
    previewDocument,
    previewVisible,
    selectedTypeId,
    editionForm,
    customFieldInputs,
    historyFieldLabels,

    // Computed
    canEdit,
    canSubmit,
    componentTypeList,
    selectedType,
    selectedTypeStructure,
    structureSelections,
    pieceSlotEntries,
    productSlotEntries,
    subcomponentSlotEntries,

    // History
    history,
    historyLoading,
    historyError,

    // Methods
    openPreview,
    closePreview,
    removeDocument,
    handleFilesAdded,
    refreshDocuments,
    submitEdition,
    saveSlotQuantity,
    savePieceSlotSelection,
    saveProductSlotSelection,
    saveSubcomponentSlotSelection,
    resolvePieceLabel,
    resolveProductLabel,
    resolveSubcomponentLabel,
    formatStructurePreview,
  }
}