/**
 * Lookup cascade (bağımlı açılır liste) davranışı.
 * Grid ve Tree aynı kuralları paylaşır.
 */
import type { GridDto } from '@/proxy/form/models'

export type CascadeInfo = {
  parentFields: string[]
  childFields?: string[]
}

export type CascadeMaps = {
  /** fieldName -> cascade bilgisi */
  cascadeFieldsMap: Map<string, CascadeInfo>
  /** parentField -> etkilediği child alan adları */
  parentToChildrenMap: Map<string, Set<string>>
}

const splitFields = (value?: string | null) =>
  (value ?? '')
    .split(',')
    .map((field) => field.trim())
    .filter(Boolean)

export const createCascadeMaps = (gridDto?: GridDto): CascadeMaps => {
  const cascadeFieldsMap = new Map<string, CascadeInfo>()
  const parentToChildrenMap = new Map<string, Set<string>>()

  gridDto?.columnFormats.forEach((col) => {
    if (!col.fieldName || !col.lookupDto?.cascadeParentFields) return

    const parentFields = splitFields(col.lookupDto.cascadeParentFields)
    const childFields = col.lookupDto.cascadeEmptyFields
      ? splitFields(col.lookupDto.cascadeEmptyFields)
      : undefined

    cascadeFieldsMap.set(col.fieldName, { parentFields, childFields })

    parentFields.forEach((parentField) => {
      const children = parentToChildrenMap.get(parentField) ?? new Set<string>()
      children.add(col.fieldName!)
      parentToChildrenMap.set(parentField, children)
    })
  })

  return { cascadeFieldsMap, parentToChildrenMap }
}

type AttachCascadeParams = {
  editor: any
  gridDto: GridDto
  cascadeInfo: CascadeInfo
  maps: CascadeMaps
}

/**
 * `onEditorPreparing` içinde cascade davranışını editöre bağlar:
 * - parent değiştiğinde child alanları temizler,
 * - etkilenen child editörlerin `disabled` durumunu günceller,
 * - form ilk açıldığında parent'ı boş olan alanı devre dışı bırakır.
 */
export const attachCascadeBehavior = ({
  editor,
  gridDto,
  cascadeInfo,
  maps,
}: AttachCascadeParams) => {
  const { cascadeFieldsMap, parentToChildrenMap } = maps
  const affectedChildren = parentToChildrenMap.get(editor.dataField)
  const previousHandler = editor.editorOptions.onValueChanged

  editor.editorOptions.onValueChanged = (e: any) => {
    previousHandler?.(e)

    const grid = editor.component
    const rowKey = grid.option('editing.editRowKey')
    const rowIndex = grid.getRowIndexByKey(rowKey)

    // Parent değiştiğinde bağımlı alanları temizle.
    if (cascadeInfo.childFields && rowIndex >= 0) {
      cascadeInfo.childFields.forEach((childField) => grid.cellValue(rowIndex, childField, null))
    }

    if (!affectedChildren?.size) return

    const formInstance = grid.option('editing.form') as any
    if (!formInstance?.getEditor) return

    const rowData = grid.getVisibleRows().find((row: any) => row.key === rowKey)?.data
    if (!rowData) return

    affectedChildren.forEach((childFieldName) => {
      const childInfo = cascadeFieldsMap.get(childFieldName)
      if (!childInfo) return

      try {
        const childColumn = gridDto.columnFormats.find(
          (column) => column.fieldName === childFieldName,
        )
        const childEditorOptions = childColumn?.editorOptions
          ? JSON.parse(childColumn.editorOptions)
          : {}
        const childEditor = formInstance.getEditor(childFieldName)

        childEditor?.option(
          'disabled',
          childEditorOptions?.disabled === true ||
            childInfo.parentFields.some((parentField) => !rowData[parentField]),
        )
      } catch (err) {
        console.error(`Cascade child editor güncellenemedi: "${childFieldName}"`, err)
      }
    })
  }

  // İlk açılışta parent'ı dolu değilse editörü kilitle.
  const grid = editor.component
  const rowKey = grid.option('editing.editRowKey')
  const rowData = grid.getVisibleRows().find((row: any) => row.key === rowKey)?.data

  if (rowData && cascadeInfo.parentFields.some((parentField) => !rowData[parentField])) {
    editor.editorOptions.disabled = true
  }
}