import { ApplogValue, DatomPart } from '../applog/datom-types.ts'

export function includes(str: string) {
	return (vl: DatomPart) => vl?.includes?.(str)
}
export function includedIn(arr: string[]) {
	return (vl: DatomPart) => arr?.includes?.(vl)
}

/**
 * Set-membership matcher: matches when the field equals any of `vals`. Use this instead of a
 * bare array in a query pattern — bare arrays are rejected by the matcher (a bare array is
 * ambiguous now that `vl` can hold a literal array value).
 *
 * Returns a `Set`, which the matcher engine checks via `.has` (O(1)). Members must be
 * primitives: `Set.has` is referential, so object/array members would silently never match —
 * we throw rather than fail silently. For object membership, use a predicate matcher, e.g.
 * `(v) => members.some(m => isEqual(v, m))`.
 */
export function anyOf<T extends ApplogValue>(...vals: T[]): ReadonlySet<T> {
	for (const v of vals) {
		if (v !== null && typeof v === 'object') {
			throw new Error(
				`[anyOf] object/array members are not supported (referential Set membership would silently never match).`
					+ ` Use a predicate matcher instead, e.g. (v) => members.some(m => isEqual(v, m)).`,
			)
		}
	}
	return new Set(vals)
}