lbry-desktop/ui/util/hex.js
2021-03-03 12:54:06 -05:00

50 lines
1.5 KiB
JavaScript

// @flow
const EMOJI_REGEX = /(?:[\u2700-\u27bf]|(?:\ud83c[\udde6-\uddff]){2}|[\ud800-\udbff][\udc00-\udfff])[\ufe0e\ufe0f]?(?:[\u0300-\u036f\ufe20-\ufe23\u20d0-\u20f0]|\ud83c[\udffb-\udfff])?(?:\u200d(?:[^\ud800-\udfff]|(?:\ud83c[\udde6-\uddff]){2}|[\ud800-\udbff][\udc00-\udfff])[\ufe0e\ufe0f]?(?:[\u0300-\u036f\ufe20-\ufe23\u20d0-\u20f0]|\ud83c[\udffb-\udfff])?)*/g;
export function toHex(str: string): string {
const array = Array.from(str);
let result = '';
for (var i = 0; i < array.length; i++) {
const val = array[i];
const isEmoji = EMOJI_REGEX.test(val);
const utf = isEmoji
? toUTF8Array(val)
.map((num) => num.toString(16))
.join('')
: val.charCodeAt(0).toString(16);
result += utf;
}
return result;
}
function toUTF8Array(str) {
var utf8 = [];
for (var i = 0; i < str.length; i++) {
var charcode = str.charCodeAt(i);
if (charcode < 0x80) utf8.push(charcode);
else if (charcode < 0x800) {
utf8.push(0xc0 | (charcode >> 6), 0x80 | (charcode & 0x3f));
} else if (charcode < 0xd800 || charcode >= 0xe000) {
utf8.push(0xe0 | (charcode >> 12), 0x80 | ((charcode >> 6) & 0x3f), 0x80 | (charcode & 0x3f));
}
// surrogate pair
else {
i++;
charcode = (((charcode & 0x3ff) << 10) | (str.charCodeAt(i) & 0x3ff)) + 0x010000;
utf8.push(
0xf0 | (charcode >> 18),
0x80 | ((charcode >> 12) & 0x3f),
0x80 | ((charcode >> 6) & 0x3f),
0x80 | (charcode & 0x3f)
);
}
}
return utf8;
}