CoastalCommitsPastes/client/lib/generate-uuid.ts

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2022-03-06 19:46:59 -05:00
export default function generateUUID() {
if (typeof crypto === 'object') {
if (typeof crypto.randomUUID === 'function') {
// https://developer.mozilla.org/en-US/docs/Web/API/Crypto/randomUUID
return crypto.randomUUID();
}
if (typeof crypto.getRandomValues === 'function' && typeof Uint8Array === 'function') {
// https://stackoverflow.com/questions/105034/how-to-create-a-guid-uuid
const callback = (c: string) => {
const num = Number(c);
return (num ^ (crypto.getRandomValues(new Uint8Array(1))[0] & (15 >> (num / 4)))).toString(16);
};
return '10000000-1000-4000-8000-100000000000'.replace(/[018]/g, callback);
}
}
let timestamp = new Date().getTime();
let perforNow = (typeof performance !== 'undefined' && performance.now && performance.now() * 1000) || 0;
return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
let random = Math.random() * 16;
if (timestamp > 0) {
random = (timestamp + random) % 16 | 0;
timestamp = Math.floor(timestamp / 16);
} else {
random = (perforNow + random) % 16 | 0;
perforNow = Math.floor(perforNow / 16);
}
return (c === 'x' ? random : (random & 0x3) | 0x8).toString(16);
});
};