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export { textToBase64, base64ToText, isValidBase64, removePotentialDataAndMimePrefix };
function textToBase64(str: string, { makeUrlSafe = false }: { makeUrlSafe?: boolean } = {}) {
const encoded = window.btoa(str);
return makeUrlSafe ? makeUriSafe(encoded) : encoded;
}
function base64ToText(str: string, { makeUrlSafe = false }: { makeUrlSafe?: boolean } = {}) {
if (!isValidBase64(str, { makeUrlSafe })) {
throw new Error('Incorrect base64 string');
}
let cleanStr = removePotentialDataAndMimePrefix(str);
if (makeUrlSafe) {
cleanStr = unURI(cleanStr);
}
try {
return window.atob(cleanStr);
}
catch (_) {
throw new Error('Incorrect base64 string');
}
}
function removePotentialDataAndMimePrefix(str: string) {
return str.replace(/^data:.*?;base64,/, '');
}
function isValidBase64(str: string, { makeUrlSafe = false }: { makeUrlSafe?: boolean } = {}) {
let cleanStr = removePotentialDataAndMimePrefix(str);
if (makeUrlSafe) {
cleanStr = unURI(cleanStr);
}
try {
if (makeUrlSafe) {
return removePotentialPadding(window.btoa(window.atob(cleanStr))) === cleanStr;
}
return window.btoa(window.atob(cleanStr)) === cleanStr;
}
catch (err) {
return false;
}
}
function makeUriSafe(encoded: string) {
return encoded.replace(/=/g, '').replace(/\+/g, '-').replace(/\//g, '_');
}
function unURI(encoded: string): string {
return encoded
.replace(/-/g, '+')
.replace(/_/g, '/')
.replace(/[^A-Za-z0-9+/]/g, '');
}
function removePotentialPadding(str: string) {
return str.replace(/=/g, '');
}
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