humanspeak / svelte-headless-table / 12913869200

import type { DeriveFlatColumnsFn, NewTablePropSet, TablePlugin } from '../types/TablePlugin.js'

import { derived, writable, type Writable } from 'svelte/store'

export interface ColumnOrderConfig {

    initialColumnIdOrder?: string[]

    hideUnspecifiedColumns?: boolean

}

export interface ColumnOrderState {

    columnIdOrder: Writable<string[]>

}

export const addColumnOrder =

    <Item>({

        initialColumnIdOrder = [],

        hideUnspecifiedColumns = false

    }: ColumnOrderConfig = {}): TablePlugin<

        Item,

        ColumnOrderState,

        Record<string, never>,

        NewTablePropSet<never>

    > =>

    () => {

        const columnIdOrder = writable<string[]>(initialColumnIdOrder)

        const pluginState: ColumnOrderState = { columnIdOrder }

        const deriveFlatColumns: DeriveFlatColumnsFn<Item> = (flatColumns) => {

            return derived([flatColumns, columnIdOrder], ([$flatColumns, $columnIdOrder]) => {

                const _flatColumns = [...$flatColumns]

                const orderedFlatColumns: typeof $flatColumns = []

                $columnIdOrder.forEach((id) => {

                    const colIdx = _flatColumns.findIndex((c) => c.id === id)

                    orderedFlatColumns.push(..._flatColumns.splice(colIdx, 1))

                })

                if (!hideUnspecifiedColumns) {

                    // Push the remaining unspecified columns.

                    orderedFlatColumns.push(..._flatColumns)

                }

                return orderedFlatColumns

            })

        }

        return {

            pluginState,

            deriveFlatColumns

        }

    }