seitu/dist/core/debounced-fn/index.mjs

import { createReadableSubscription, createSubscription } from "../subscription/index.mjs";
//#region src/core/debounced-fn/index.ts
/**
* Debounced callable that is also a subscribable. Each call resets the timer;
* the return value becomes the current state.
*
* @example
* ```ts twoslash
* import { createDebouncedFn } from 'seitu'
*
* const search = createDebouncedFn((query: string) => fetch(`/api?q=${query}`), 300)
* search.subscribe(result => console.log('result:', result))
* search('hello') // debounced — fires after 300ms of inactivity
* search.get()
* search.flush()
* search.cancel()
* ```
*/
function createDebouncedFn(fn, wait) {
	let state;
	let timeoutId;
	let pendingArgs;
	const { subscribe, notify } = createSubscription();
	const get = () => state;
	const cancel = () => {
		clearTimeout(timeoutId);
		timeoutId = void 0;
		pendingArgs = void 0;
	};
	const run = () => {
		const args = pendingArgs;
		cancel();
		state = fn(...args);
		notify();
	};
	const flush = () => {
		if (timeoutId !== void 0) run();
	};
	return Object.assign((...args) => {
		clearTimeout(timeoutId);
		pendingArgs = args;
		timeoutId = setTimeout(run, wait);
	}, createReadableSubscription(get, subscribe, notify), {
		cancel,
		flush,
		pending: () => timeoutId !== void 0
	});
}
//#endregion
export { createDebouncedFn };