Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 | 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x | import { IterableWeakSet } from '../algorithms/iterable-weak-struct.js'
import { timeNowFrame } from '../algorithms/time.utils.js'
/**
* A margin that improves the reliability of the next time value to change
* due to possible protections to fingerprinting on the client side
*
* {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/now}
*/
const MARGIN_MILLIS = 100
/**
* @param {TimeTickInstance["data"]} newInstance - target time tick instance
*/
function checkTick (newInstance) {
const { callbacks, tickingElements, timeoutNumber } = newInstance
if (timeoutNumber === undefined && tickingElements.size > 0 && callbacks.size > 0) {
const nextSecond = 1000 - timeNowFrame() % 1000
newInstance.timeoutNumber = setTimeout(() => {
for (const tickCallback of callbacks) {
tickCallback({
targets: [...tickingElements],
untick: (el) => tickingElements.delete(el),
})
}
newInstance.timeoutNumber = undefined
checkTick(newInstance)
}, nextSecond + MARGIN_MILLIS)
}
}
/**
* Builds a time tick instance
*/
function buildTimeTick () {
const data = {
/** @type {IterableWeakSet<Element>} */
tickingElements: new IterableWeakSet(),
/** @type {ReturnType<typeof setTimeout> | undefined} */
timeoutNumber: undefined,
/** @type {Set<TimeTickCallback>} */
callbacks: new Set(),
}
const api = {
/** @param {Element} element - target element */
tickElement: (element) => {
data.tickingElements.add(element)
checkTick(data)
},
/** @param {Element} element - target element */
untickElement: (element) => {
data.tickingElements.delete(element)
},
/** @param {TimeTickCallback} callback - callback to trigger each time tick */
addCallback: (callback) => {
data.callbacks.add(callback)
checkTick(data)
},
/** @param {TimeTickCallback} callback - callback to trigger each time tick */
removeCallback: (callback) => {
data.callbacks.delete(callback)
},
}
return { api, data }
}
/** @type {TimeTickInstance} */
let timeTickInstances
/**
* @returns {TimeTickApi} singleton time tick instance
*/
export function timeTick () {
timeTickInstances ??= buildTimeTick()
return timeTickInstances.api
}
/**
* @typedef {object} TimeTickCallbackParams
* @property {Element[]} targets - target ticking elements
* @property {(el: Element) => void} untick - stop ticking an element, does nothing if already not ticking
*/
/**
* @typedef {ReturnType<typeof buildTimeTick>} TimeTickInstance
*/
/**
* @typedef {TimeTickInstance["api"]} TimeTickApi
*/
/**
* @callback TimeTickCallback
* @param {TimeTickCallbackParams} param
*/
|