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const cacheStore = new WeakMap<AnyFunction, CacheStorage<any, any>>();

export default function mem<
	FunctionToMemoize extends AnyFunction,
	CacheKeyType,
>(
	fn: FunctionToMemoize,
	{
		cacheKey,
		cache = new Map(),
		maxAge,
	}: Options<FunctionToMemoize, CacheKeyType> = {},
): FunctionToMemoize {
	if (typeof maxAge === 'number') {
		mapAgeCleaner(cache as unknown as Map<CacheKeyType, ReturnType<FunctionToMemoize>>);
	}

	const memoized = function (this: any, ...arguments_: Parameters<FunctionToMemoize>): ReturnType<FunctionToMemoize> {
		const key = cacheKey ? cacheKey(arguments_) : arguments_[0] as CacheKeyType;

		const cacheItem = cache.get(key);
		if (cacheItem) {
			return cacheItem.data; // eslint-disable-line @typescript-eslint/no-unsafe-return
		}

		const result = fn.apply(this, arguments_) as ReturnType<FunctionToMemoize>;

		cache.set(key, {
			data: result,
			maxAge: maxAge ? Date.now() + maxAge : Number.POSITIVE_INFINITY,
		});

		return result; // eslint-disable-line @typescript-eslint/no-unsafe-return
	} as FunctionToMemoize;

	mimicFn(memoized, fn, {
		ignoreNonConfigurable: true,
	});

	cacheStore.set(memoized, cache);

	return memoized;
}