type TypedArray = Int8Array | Uint8Array | Uint8ClampedArray | Int16Array | Uint16Array | Int32Array | Uint32Array | Float32Array | Float64Array | BigInt64Array | BigUint64Array

export const at = {
	at<T extends Array<any> | string | TypedArray>(this: T, index: number) {
		index = Math.trunc(index) || 0
	
		if (index < 0) index += this.length;
	
		if (index < 0 || index >= this.length) return undefined;
	
		return this[index];
	}
}.at

export const initRelativeIndexingMethod = (target: any, exclude: Set<string>) => {
	if (exclude.has('at')) return

	const Classes = []

	if (!exclude.has('TypedArray')) Classes.push(Object.getPrototypeOf(target.Int8Array || globalThis.Int8Array))
	if (!exclude.has('Array')) Classes.push(target.Array || globalThis.Array)
	if (!exclude.has('String')) Classes.push(target.String || globalThis.String)

	for (const Class of Classes) {
		if (!Class.prototype.at) Object.defineProperty(Class.prototype, 'at', {
			value: at,
			writable: true,
			enumerable: false,
			configurable: true
		})
	}
}