/* eslint no-proto:0 */
import { classOf } from '../langs/classOf';

/**
 * Clone an object using structured cloning algorithm
 *
 * - Chrome 98, Safari 15.4, NodeJS 17
 *
 * @see {@link https://developer.mozilla.org/en-US/docs/Web/API/structuredClone structuredClone}
 * @see {@link https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/web.structured-clone.js core-js}
 */
export const structuredClone: <T>(value: T, options?: StructuredSerializeOptions) => T =
	globalThis.structuredClone || _clone;

function set(obj: any, key: any, val: any) {
	if (typeof val.value === 'object') val.value = _clone(val.value);
	if (!val.enumerable || val.get || val.set || !val.configurable || !val.writable || key === '__proto__') {
		Object.defineProperty(obj, key, val);
	} else obj[key] = val.value;
}

/**
 * @see {@link https://github.com/lukeed/klona/blob/master/src/full.js klona}
 */
export function _clone(x: any): any {
	// too complex
	// https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/web.structured-clone.js

	if (typeof x !== 'object') return x;

	let i = 0;
	let k: string | number;
	let list: any[] | Set<any> | Map<any, any>;
	let tmp: any;
	const str = classOf(x);
	switch (str) {
		case 'Array':
			tmp = Array(x.length);
			break;
		case 'Object':
			tmp = Object.create(x.__proto__ || null);
			break;
		case 'Set':
			tmp = new Set();
			x.forEach((val: any) => {
				tmp.add(_clone(val));
			});
			break;
		case 'Map':
			tmp = new Map();
			x.forEach((val: any, key: any) => {
				tmp.set(_clone(key), _clone(val));
			});
			break;
		case 'Date':
			tmp = new Date(+x);
			break;
		case 'RegExp':
			tmp = new RegExp(x.source, x.flags);
			break;
		case 'DataView':
			tmp = new x.constructor(_clone(x.buffer));
			break;
		case 'ArrayBuffer':
			tmp = x.slice(0);
			break;
		default:
			// typed arrays
			if (str.endsWith('Array')) {
				// ArrayBuffer.isView(x)
				// ~> `new` bcuz `Buffer.slice` => ref
				tmp = new x.constructor(x);
			}
	}

	if (tmp) {
		for (list = Object.getOwnPropertySymbols(x); i < list.length; i++) {
			set(tmp, list[i], Object.getOwnPropertyDescriptor(x, list[i]));
		}

		for (i = 0, list = Object.getOwnPropertyNames(x); i < list.length; i++) {
			if (Object.hasOwn(tmp, (k = list[i])) && tmp[k] === x[k]) continue;
			set(tmp, k, Object.getOwnPropertyDescriptor(x, k));
		}
	}

	return tmp || x;
}