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base64.js
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base64.js
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export default class Base64 {
static _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
static encode(input) {
let output = "";
let chr1, chr2, chr3, enc1, enc2, enc3, enc4;
let i = 0;
input = Base64._utf8_encode(input);
while (i < input.length) {
chr1 = input.charCodeAt(i++);
chr2 = input.charCodeAt(i++);
chr3 = input.charCodeAt(i++);
enc1 = chr1 >> 2;
enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
enc4 = chr3 & 63;
if (isNaN(chr2)) {
enc3 = enc4 = 64;
} else if (isNaN(chr3)) {
enc4 = 64;
}
output = output + Base64._keyStr.charAt(enc1) +
Base64._keyStr.charAt(enc2) +
Base64._keyStr.charAt(enc3) +
Base64._keyStr.charAt(enc4);
}
return output;
}
static decode(input) {
let output = "";
let chr1, chr2, chr3;
let enc1, enc2, enc3, enc4;
let i = 0;
input = input.replace(/[^A-Za-z0-9+/=]/g, "");
while (i < input.length) {
enc1 = Base64._keyStr.indexOf(input.charAt(i++));
enc2 = Base64._keyStr.indexOf(input.charAt(i++));
enc3 = Base64._keyStr.indexOf(input.charAt(i++));
enc4 = Base64._keyStr.indexOf(input.charAt(i++));
chr1 = (enc1 << 2) | (enc2 >> 4);
chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
chr3 = ((enc3 & 3) << 6) | enc4;
output = output + String.fromCharCode(chr1);
if (enc3 !== 64) {
output = output + String.fromCharCode(chr2);
}
if (enc4 !== 64) {
output = output + String.fromCharCode(chr3);
}
}
output = Base64._utf8_decode(output);
return output;
}
static _utf8_encode(str) {
str = str.replace(/\r\n/g, "\n");
let utfText = "";
for (let n = 0; n < str.length; n++) {
let c = str.charCodeAt(n);
if (c < 128) {
utfText += String.fromCharCode(c);
}
else if ((c > 127) && (c < 2048)) {
utfText += String.fromCharCode((c >> 6) | 192);
utfText += String.fromCharCode((c & 63) | 128);
}
else {
utfText += String.fromCharCode((c >> 12) | 224);
utfText += String.fromCharCode(((c >> 6) & 63) | 128);
utfText += String.fromCharCode((c & 63) | 128);
}
}
return utfText;
}
static _utf8_decode(utfText) {
let str = "";
let i = 0;
let c = 0;
let c2 = 0;
let c3 = 0;
while (i < utfText.length) {
c = utfText.charCodeAt(i);
if (c < 128) {
str += String.fromCharCode(c);
i++;
}
else if ((c > 191) && (c < 224)) {
c2 = utfText.charCodeAt(i + 1);
str += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
i += 2;
}
else {
c2 = utfText.charCodeAt(i + 1);
c3 = utfText.charCodeAt(i + 2);
str += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
i += 3;
}
}
return str;
}
}