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/* eslint no-invalid-this: 0 */
/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
*/
const ZBase32Alphabet = "ybndrfg8ejkmcpqxot1uwisza345h769";
export var EnigmailZBase32 = {
a: ZBase32Alphabet,
pad: "=",
/**
* Encode a string in Z-Base-32 encoding
*
* @param {string} str - Input string
*
* @returns {string} the encoded string.
*/
encode(str) {
const a = this.a;
const pad = this.pad;
const len = str.length;
let o = "";
let w,
c,
r = 0,
sh = 0;
for (let i = 0; i < len; i += 5) {
// mask top 5 bits
c = str.charCodeAt(i);
w = 0xf8 & c;
o += a.charAt(w >> 3);
r = 0x07 & c;
sh = 2;
if (i + 1 < len) {
c = str.charCodeAt(i + 1);
// mask top 2 bits
w = 0xc0 & c;
o += a.charAt((r << 2) + (w >> 6));
o += a.charAt((0x3e & c) >> 1);
r = c & 0x01;
sh = 4;
}
if (i + 2 < len) {
c = str.charCodeAt(i + 2);
// mask top 4 bits
w = 0xf0 & c;
o += a.charAt((r << 4) + (w >> 4));
r = 0x0f & c;
sh = 1;
}
if (i + 3 < len) {
c = str.charCodeAt(i + 3);
// mask top 1 bit
w = 0x80 & c;
o += a.charAt((r << 1) + (w >> 7));
o += a.charAt((0x7c & c) >> 2);
r = 0x03 & c;
sh = 3;
}
if (i + 4 < len) {
c = str.charCodeAt(i + 4);
// mask top 3 bits
w = 0xe0 & c;
o += a.charAt((r << 3) + (w >> 5));
o += a.charAt(0x1f & c);
r = 0;
sh = 0;
}
}
// Calculate length of pad by getting the
// number of words to reach an 8th octet.
if (r != 0) {
o += a.charAt(r << sh);
}
var padlen = 8 - (o.length % 8);
if (padlen === 8) {
return o;
}
if (padlen === 1 || padlen === 3 || padlen === 4 || padlen === 6) {
return o + pad.repeat(padlen);
}
throw new Error(
"there was some kind of error:\npadlen:" +
padlen +
" ,r:" +
r +
" ,sh:" +
sh +
", w:" +
w
);
},
};