import { ModelRef, onBeforeMount, ref, watch } from 'vue'
import { KettalQTableColumn, KettalVisibleColumn } from '@/types/KTable'

export default function usePrepareTableColumns (visibleColumns: ModelRef<KettalVisibleColumn[]>, props: { rows: any[], columns: KettalQTableColumn[], }) {
  const localColumns = ref<KettalQTableColumn[]>([])
  const localVisibleColumns = ref<string[]>([])

  watch(() => visibleColumns.value, () => {
    prepareVisibleAndOrderColumns()
  },
  { deep: true }
  )

  onBeforeMount(() => {
    if (!Array.isArray(props.rows)) {
      console.error('Receiving props.rows as ', props.rows)
      throw new Error('Rows must be an array.')
    }
    prepareVisibleAndOrderColumns()
  })

  function prepareVisibleAndOrderColumns () {
    // For some reason, sometimes visibleColumns did not update so it threw an error when doing the localColumns mapping
    if (visibleColumns.value === undefined ||
        visibleColumns.value.length === 0 ||
          !(Array.isArray(visibleColumns.value) && visibleColumns.value.every((value: unknown) => {
            const obj = value as KettalVisibleColumn
            return typeof obj.name === 'string' && typeof obj.isVisible === 'boolean'
          }))
    ) {
      // visibleColumns = columns.map((column) => { return { name: column.name, isVisible: true } })
      while (visibleColumns.value.length > 0) {
        visibleColumns.value.pop()
      }
      props.columns.map((column) => { return { name: column.name, isVisible: true } }).forEach((column) => {
        visibleColumns.value.push(column)
      })
    }
    localVisibleColumns.value = visibleColumns.value.filter((value: unknown) => {
      const column = value as KettalVisibleColumn
      return column.isVisible
    }).map((value: unknown) => {
      const column = value as KettalQTableColumn
      return column.name
    })
    const aux = visibleColumns.value.map((value: KettalVisibleColumn) => {
      const column = props.columns.find((col) => col.name === value.name) as KettalQTableColumn
      if (column) {
        return column
      } else {
        console.error('Column "' + value.name + '" in Visible Columns not found in Columns')
        return null
      }
    })

    localColumns.value = aux.filter((value) => value !== null) as KettalQTableColumn[]
  }

  return { localColumns, localVisibleColumns, prepareVisibleAndOrderColumns }
}