import { ref, computed, watch } from 'vue'
import { $t } from '@/locales'
const SPECIAL_COLUMNS = {
  selection: { prop: '__selection__', label: $t('table.column.selection') },
  expand: { prop: '__expand__', label: $t('table.column.expand') },
  index: { prop: '__index__', label: $t('table.column.index') }
}
const getColumnKey = (col) => SPECIAL_COLUMNS[col.type]?.prop ?? col.prop
const getColumnVisibility = (col) => {
  if (col.visible !== void 0) {
    return col.visible
  }
  return col.checked ?? true
}
const getColumnChecks = (columns) =>
  columns.map((col) => {
    const special = col.type && SPECIAL_COLUMNS[col.type]
    const visibility = getColumnVisibility(col)
    if (special) {
      return { ...col, prop: special.prop, label: special.label, checked: true, visible: true }
    }
    return { ...col, checked: visibility, visible: visibility }
  })
function useTableColumns(columnsFactory) {
  const dynamicColumns = ref(columnsFactory())
  const columnChecks = ref(getColumnChecks(dynamicColumns.value))
  watch(
    dynamicColumns,
    (newCols) => {
      const visibilityMap = new Map(
        columnChecks.value.map((c) => [getColumnKey(c), getColumnVisibility(c)])
      )
      const newChecks = getColumnChecks(newCols).map((c) => {
        const key = getColumnKey(c)
        const visibility = visibilityMap.has(key) ? visibilityMap.get(key) : getColumnVisibility(c)
        return {
          ...c,
          checked: visibility,
          visible: visibility
        }
      })
      columnChecks.value = newChecks
    },
    { deep: true }
  )
  const columns = computed(() => {
    const colMap = new Map(dynamicColumns.value.map((c) => [getColumnKey(c), c]))
    return columnChecks.value
      .filter((c) => getColumnVisibility(c))
      .map((c) => colMap.get(getColumnKey(c)))
      .filter(Boolean)
  })
  const setDynamicColumns = (updater) => {
    const copy = [...dynamicColumns.value]
    const result = updater(copy)
    dynamicColumns.value = Array.isArray(result) ? result : copy
  }
  return {
    columns,
    columnChecks,
    /**
     * 新增列（支持单个或批量）
     */
    addColumn: (column, index) =>
      setDynamicColumns((cols) => {
        const next = [...cols]
        const columnsToAdd = Array.isArray(column) ? column : [column]
        const insertIndex =
          typeof index === 'number' && index >= 0 && index <= next.length ? index : next.length
        next.splice(insertIndex, 0, ...columnsToAdd)
        return next
      }),
    /**
     * 删除列（支持单个或批量）
     */
    removeColumn: (prop) =>
      setDynamicColumns((cols) => {
        const propsToRemove = Array.isArray(prop) ? prop : [prop]
        return cols.filter((c) => !propsToRemove.includes(getColumnKey(c)))
      }),
    /**
     * 更新列（支持单个或批量）
     */
    updateColumn: (prop, updates) => {
      if (Array.isArray(prop)) {
        setDynamicColumns((cols) => {
          const map = new Map(prop.map((u) => [u.prop, u.updates]))
          return cols.map((c) => {
            const key = getColumnKey(c)
            const upd = map.get(key)
            return upd ? { ...c, ...upd } : c
          })
        })
      } else if (updates) {
        setDynamicColumns((cols) =>
          cols.map((c) => (getColumnKey(c) === prop ? { ...c, ...updates } : c))
        )
      }
    },
    /**
     * 切换列显示状态（支持单个或批量）
     */
    toggleColumn: (prop, visible) => {
      const propsToToggle = Array.isArray(prop) ? prop : [prop]
      const next = [...columnChecks.value]
      propsToToggle.forEach((p) => {
        const i = next.findIndex((c) => getColumnKey(c) === p)
        if (i > -1) {
          const currentVisibility = getColumnVisibility(next[i])
          const newVisibility = visible ?? !currentVisibility
          next[i] = { ...next[i], checked: newVisibility, visible: newVisibility }
        }
      })
      columnChecks.value = next
    },
    /**
     * 重置所有列
     */
    resetColumns: () => {
      dynamicColumns.value = columnsFactory()
    },
    /**
     * 批量更新列（兼容旧版本）
     * @deprecated 推荐使用 updateColumn 的数组模式
     */
    batchUpdateColumns: (updates) =>
      setDynamicColumns((cols) => {
        const map = new Map(updates.map((u) => [u.prop, u.updates]))
        return cols.map((c) => {
          const key = getColumnKey(c)
          const upd = map.get(key)
          return upd ? { ...c, ...upd } : c
        })
      }),
    /**
     * 重新排序列
     */
    reorderColumns: (fromIndex, toIndex) =>
      setDynamicColumns((cols) => {
        if (
          fromIndex < 0 ||
          fromIndex >= cols.length ||
          toIndex < 0 ||
          toIndex >= cols.length ||
          fromIndex === toIndex
        ) {
          return cols
        }
        const next = [...cols]
        const [moved] = next.splice(fromIndex, 1)
        next.splice(toIndex, 0, moved)
        return next
      }),
    /**
     * 获取列配置
     */
    getColumnConfig: (prop) => dynamicColumns.value.find((c) => getColumnKey(c) === prop),
    /**
     * 获取所有列配置
     */
    getAllColumns: () => [...dynamicColumns.value]
  }
}
export { getColumnChecks, getColumnKey, getColumnVisibility, useTableColumns }