// eslint-disable-next-line @typescript-eslint/ban-ts-comment // @ts-nocheck /** Error message constants. */ const FUNC_ERROR_TEXT = 'Expected a function'; interface IDebounceOptions { leading?: boolean; maxWait?: number; trailing?: boolean; } type IThrottleOptions = IDebounceOptions; function throttle(func, wait: number, options?: IThrottleOptions) { let leading = true, trailing = true; if (typeof func != 'function') { throw new TypeError(FUNC_ERROR_TEXT); } if (options && isObject(options)) { leading = 'leading' in options ? !!options.leading : leading; trailing = 'trailing' in options ? !!options.trailing : trailing; } return debounce(func, wait, { leading: leading, maxWait: wait, trailing: trailing, }); } function debounce(func, wait: number, options?: IDebounceOptions) { let lastArgs, lastThis, maxWait, result, timerId, lastCallTime, lastInvokeTime = 0, leading = false, maxing = false, trailing = true; if (typeof func != 'function') { throw new TypeError(FUNC_ERROR_TEXT); } wait = wait || 0; if (options && isObject(options)) { leading = !!options.leading; maxing = 'maxWait' in options; maxWait = maxing ? Math.max(options.maxWait || 0, wait) : maxWait; trailing = 'trailing' in options ? !!options.trailing : trailing; } function invokeFunc(time) { const args = lastArgs, thisArg = lastThis; lastArgs = lastThis = undefined; lastInvokeTime = time; result = func.apply(thisArg, args); return result; } function leadingEdge(time) { // Reset any `maxWait` timer. lastInvokeTime = time; // Start the timer for the trailing edge. timerId = setTimeout(timerExpired, wait); // Invoke the leading edge. return leading ? invokeFunc(time) : result; } function remainingWait(time) { const timeSinceLastCall = time - lastCallTime, timeSinceLastInvoke = time - lastInvokeTime, timeWaiting = wait - timeSinceLastCall; return maxing ? Math.min(timeWaiting, maxWait - timeSinceLastInvoke) : timeWaiting; } function shouldInvoke(time) { const timeSinceLastCall = time - lastCallTime, timeSinceLastInvoke = time - lastInvokeTime; // Either this is the first call, activity has stopped and we're at the // trailing edge, the system time has gone backwards and we're treating // it as the trailing edge, or we've hit the `maxWait` limit. return (lastCallTime === undefined || (timeSinceLastCall >= wait) || (timeSinceLastCall < 0) || (maxing && timeSinceLastInvoke >= maxWait)); } function timerExpired() { const time = Date.now(); if (shouldInvoke(time)) { return trailingEdge(time); } // Restart the timer. timerId = setTimeout(timerExpired, remainingWait(time)); } function trailingEdge(time) { timerId = undefined; // Only invoke if we have `lastArgs` which means `func` has been // debounced at least once. if (trailing && lastArgs) { return invokeFunc(time); } lastArgs = lastThis = undefined; return result; } function cancel() { if (timerId !== undefined) { clearTimeout(timerId); } lastInvokeTime = 0; lastArgs = lastCallTime = lastThis = timerId = undefined; } function flush() { return timerId === undefined ? result : trailingEdge(Date.now()); } function debounced() { const time = Date.now(), isInvoking = shouldInvoke(time); // eslint-disable-next-line prefer-rest-params lastArgs = arguments; // @ts-expect-error ignore this type // eslint-disable-next-line @typescript-eslint/no-this-alias lastThis = this; lastCallTime = time; if (isInvoking) { if (timerId === undefined) { return leadingEdge(lastCallTime); } if (maxing) { // Handle invocations in a tight loop. clearTimeout(timerId); timerId = setTimeout(timerExpired, wait); return invokeFunc(lastCallTime); } } if (timerId === undefined) { timerId = setTimeout(timerExpired, wait); } return result; } debounced.cancel = cancel; debounced.flush = flush; return debounced; } function isObject(value) { const type = typeof value; return value != null && (type == 'object' || type == 'function'); } export { debounce, throttle, };