import { makeStateUpdater, memo } from '../utils'

import { Table, OnChangeFn, Updater, Column, RowData } from '../types'

import { orderColumns } from './Grouping'
import { TableFeature } from '../core/table'

export interface ColumnOrderTableState {
  columnOrder: ColumnOrderState
}

export type ColumnOrderState = string[]

export interface ColumnOrderOptions {
  /**
   * If provided, this function will be called with an `updaterFn` when `state.columnOrder` changes. This overrides the default internal state management, so you will need to persist the state change either fully or partially outside of the table.
   * @link [API Docs](https://tanstack.com/table/v8/docs/api/features/column-ordering#oncolumnorderchange)
   * @link [Guide](https://tanstack.com/table/v8/docs/guide/column-ordering)
   */
  onColumnOrderChange?: OnChangeFn<ColumnOrderState>
}

export interface ColumnOrderDefaultOptions {
  onColumnOrderChange: OnChangeFn<ColumnOrderState>
}

export interface ColumnOrderInstance<TData extends RowData> {
  _getOrderColumnsFn: () => (
    columns: Column<TData, unknown>[]
  ) => Column<TData, unknown>[]
  /**
   * Resets the **columnOrder** state to `initialState.columnOrder`, or `true` can be passed to force a default blank state reset to `[]`.
   * @link [API Docs](https://tanstack.com/table/v8/docs/api/features/column-ordering#resetcolumnorder)
   * @link [Guide](https://tanstack.com/table/v8/docs/guide/column-ordering)
   */
  resetColumnOrder: (defaultState?: boolean) => void
  /**
   * Sets or updates the `state.columnOrder` state.
   * @link [API Docs](https://tanstack.com/table/v8/docs/api/features/column-ordering#setcolumnorder)
   * @link [Guide](https://tanstack.com/table/v8/docs/guide/column-ordering)
   */
  setColumnOrder: (updater: Updater<ColumnOrderState>) => void
}

//

export const Ordering: TableFeature = {
  getInitialState: (state): ColumnOrderTableState => {
    return {
      columnOrder: [],
      ...state,
    }
  },

  getDefaultOptions: <TData extends RowData>(
    table: Table<TData>
  ): ColumnOrderDefaultOptions => {
    return {
      onColumnOrderChange: makeStateUpdater('columnOrder', table),
    }
  },

  createTable: <TData extends RowData>(table: Table<TData>): void => {
    table.setColumnOrder = updater =>
      table.options.onColumnOrderChange?.(updater)
    table.resetColumnOrder = defaultState => {
      table.setColumnOrder(
        defaultState ? [] : table.initialState.columnOrder ?? []
      )
    }
    table._getOrderColumnsFn = memo(
      () => [
        table.getState().columnOrder,
        table.getState().grouping,
        table.options.groupedColumnMode,
      ],
      (columnOrder, grouping, groupedColumnMode) => columns => {
        // Sort grouped columns to the start of the column list
        // before the headers are built
        let orderedColumns: Column<TData, unknown>[] = []

        // If there is no order, return the normal columns
        if (!columnOrder?.length) {
          orderedColumns = columns
        } else {
          const columnOrderCopy = [...columnOrder]

          // If there is an order, make a copy of the columns
          const columnsCopy = [...columns]

          // And make a new ordered array of the columns

          // Loop over the columns and place them in order into the new array
          while (columnsCopy.length && columnOrderCopy.length) {
            const targetColumnId = columnOrderCopy.shift()
            const foundIndex = columnsCopy.findIndex(
              d => d.id === targetColumnId
            )
            if (foundIndex > -1) {
              orderedColumns.push(columnsCopy.splice(foundIndex, 1)[0]!)
            }
          }

          // If there are any columns left, add them to the end
          orderedColumns = [...orderedColumns, ...columnsCopy]
        }

        return orderColumns(orderedColumns, grouping, groupedColumnMode)
      },
      {
        key: process.env.NODE_ENV === 'development' && 'getOrderColumnsFn',
        // debug: () => table.options.debugAll ?? table.options.debugTable,
      }
    )
  },
}