Files
rts/js/helpers.js
T
2020-04-30 20:14:26 +01:00

95 lines
2.2 KiB
JavaScript

/**
* Function to randomise an array order
* @param {array} array
*/
export function shuffleArray(array) {
var currentIndex = array.length,
temporaryValue,
randomIndex;
// While there remain elements to shuffle...
while (0 !== currentIndex) {
// Pick a remaining element...
randomIndex = Math.floor(Math.random() * currentIndex);
currentIndex -= 1;
// And swap it with the current element.
temporaryValue = array[currentIndex];
array[currentIndex] = array[randomIndex];
array[randomIndex] = temporaryValue;
}
return array;
}
export function urltoFile(url, filename, mimeType) {
return fetch(url)
.then(function (res) {
return res.arrayBuffer();
})
.then(function (buf) {
return new File([buf], filename, { type: mimeType });
});
}
export function formatBytes(bytes, decimals = 2) {
if (bytes === 0) return "0 Bytes";
const k = 1024;
const dm = decimals < 0 ? 0 : decimals;
const sizes = ["Bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"];
const i = Math.floor(Math.log(bytes) / Math.log(k));
return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + " " + sizes[i];
}
export function CountDownTimer(duration, granularity) {
this.duration = duration;
this.granularity = granularity || 1000;
this.tickFtns = [];
this.running = false;
}
CountDownTimer.prototype.start = function () {
if (this.running) {
return;
}
this.running = true;
var start = Date.now(),
that = this,
diff,
obj;
(function timer() {
diff = that.duration - (((Date.now() - start) / 1000) | 0);
if (diff > 0) {
setTimeout(timer, that.granularity);
} else {
diff = 0;
that.running = false;
}
obj = CountDownTimer.parse(diff);
that.tickFtns.forEach(function (ftn) {
ftn.call(this, obj.minutes, obj.seconds);
}, that);
})();
};
CountDownTimer.prototype.onTick = function (ftn) {
if (typeof ftn === 'function') {
this.tickFtns.push(ftn);
}
return this;
};
CountDownTimer.prototype.expired = function () {
return !this.running;
};
CountDownTimer.parse = function (seconds) {
return {
'minutes': (seconds / 60) | 0,
seconds: seconds % 60 | 0,
};
};