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// @ts-check
/**
* @param {string} message
* @returns {never}
*/
function fail(message) {
throw new Error(message);
}
/**
* @param {number} value
*/
function base64FormatEncode(value) {
return value < 0 ? fail("Invalid value") :
value < 26 ? 0x41 /*A*/ + value :
value < 52 ? 0x61 /*a*/ + value - 26 :
value < 62 ? 0x30 /*0*/ + value - 52 :
value === 62 ? 0x2B /*+*/ :
value === 63 ? 0x2F /*/*/ :
fail("Invalid value");
}
/**
* @param {number} value
*/
function base64VLQFormatEncode(value) {
if (value < 0) {
value = ((-value) << 1) + 1;
}
else {
value = value << 1;
}
// Encode 5 bits at a time starting from least significant bits
let result = "";
do {
let currentDigit = value & 31; // 11111
value = value >> 5;
if (value > 0) {
// There are still more digits to decode, set the msb (6th bit)
currentDigit = currentDigit | 32;
}
result += String.fromCharCode(base64FormatEncode(currentDigit));
} while (value > 0);
return result;
}
exports.base64VLQFormatEncode = base64VLQFormatEncode;
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