rescript-debounce/src/Debounce.res.js

Debounce for ReScript

// Generated by ReScript, PLEASE EDIT WITH CARE

import * as Primitive_option from "@rescript/runtime/lib/es6/Primitive_option.js";

function makeControlled(waitOpt, fn) {
  let wait = waitOpt !== undefined ? waitOpt : 100;
  let timerId = {
    contents: undefined
  };
  let lastArg = {
    contents: undefined
  };
  let lastCallTime = {
    contents: undefined
  };
  let shouldCall = time => {
    let lastCallTime$1 = lastCallTime.contents;
    if (lastCallTime$1 === undefined) {
      return true;
    }
    let timeSinceLastCall = time - lastCallTime$1 | 0;
    if (timeSinceLastCall >= wait) {
      return true;
    } else {
      return timeSinceLastCall < 0;
    }
  };
  let remainingWait = time => {
    let lastCallTime$1 = lastCallTime.contents;
    if (lastCallTime$1 === undefined) {
      return wait;
    }
    let timeSinceLastCall = time - lastCallTime$1 | 0;
    return wait - timeSinceLastCall | 0;
  };
  let timerExpired = () => {
    let timerId$1 = timerId.contents;
    if (timerId$1 !== undefined) {
      clearTimeout(Primitive_option.valFromOption(timerId$1));
    }
    let time = Date.now() | 0;
    if (shouldCall(time)) {
      return call();
    } else {
      timerId.contents = Primitive_option.some(setTimeout(timerExpired, remainingWait(time)));
      return;
    }
  };
  let call = () => {
    let x = lastArg.contents;
    if (x !== undefined) {
      lastArg.contents = undefined;
      timerId.contents = undefined;
      return fn(Primitive_option.valFromOption(x));
    } else {
      timerId.contents = undefined;
      return;
    }
  };
  let schedule = x => {
    let time = Date.now() | 0;
    lastArg.contents = Primitive_option.some(x);
    lastCallTime.contents = time;
    timerId.contents = Primitive_option.some(setTimeout(timerExpired, wait));
  };
  let scheduled = () => timerId.contents !== undefined;
  let cancel = () => {
    let timerId$p = timerId.contents;
    if (timerId$p !== undefined) {
      clearTimeout(Primitive_option.valFromOption(timerId$p));
      timerId.contents = undefined;
      lastArg.contents = undefined;
      lastCallTime.contents = undefined;
      return;
    }
  };
  let invoke = x => {
    cancel();
    fn(x);
  };
  return {
    invoke: invoke,
    schedule: schedule,
    scheduled: scheduled,
    cancel: cancel
  };
}

function make(wait, fn) {
  return makeControlled(wait, fn).schedule;
}

export {
  make,
  makeControlled,
}
/* No side effect */