/*!
 * Copyright (c) Microsoft. All rights reserved.
 * Licensed under the MIT license. See LICENSE file in the project.
 */
import type { RecodeArgs, Value } from '@datashaper/schema'
import type { Step } from '@datashaper/workflow'
import { op } from 'arquero'
import type ColumnTable from 'arquero/dist/types/table/column-table'
import { useCallback, useMemo } from 'react'

import { EMPTY_OBJECT } from '../../../../empty.js'
import type { StepChangeFunction } from '../../../../types.js'

export function useColumnValues(
	step: Step<RecodeArgs>,
	table?: ColumnTable,
): Value[] {
	return useMemo(() => {
		const { column } = step.args
		if (!(table && column)) {
			return []
		}
		const args = {
			[column]: op.array_agg_distinct(column),
		}
		const rollup = table.orderby(column).rollup(args)
		return rollup.get(column, 0)
	}, [table, step])
}

// find the next value from the table to suggest
function next(step: Step<RecodeArgs>, values: Value[]): Value | undefined {
	return values.find((value) => {
		if (!step.args.mapping) {
			return true
		}
		return step.args.mapping[value] == null
	})
}

export function useHandleAddButtonClick(
	step: Step<RecodeArgs>,
	values: Value[],
	onChange?: StepChangeFunction<RecodeArgs>,
): () => void {
	return useCallback(() => {
		const nextValue = next(step, values)

		if (nextValue != null) {
			// could be a 0 or false...
			onChange?.({
				...step,
				args: {
					...step.args,
					mapping: {
						...step.args.mapping,
						[nextValue]: nextValue,
					},
				},
			})
		}
	}, [step, values, onChange])
}

export function useDisabled(step: Step<RecodeArgs>, values: Value[]): boolean {
	if (values.length === 0 || !step.args.column) {
		return true
	}
	return values.length === Object.keys(step.args.mapping || EMPTY_OBJECT).length
}