auth: use unicode b64 encoding on browser

brought over unicodeB64Encode/Decode from my other filaments project.
Fixes #364.

ts/modules/common.ts

@@ -291,3 +291,16 @@ export function bindManualDropdowns() {
         };
     }
 }
+
+export function unicodeB64Decode(s: string): string {
+    const decoded = atob(s);
+    const byteArray = Uint8Array.from(decoded, (m) => m.codePointAt(0));
+    const toUnicode = new TextDecoder().decode(byteArray);
+    return toUnicode;
+}
+
+export function unicodeB64Encode(s: string): string {
+    const encoded = new TextEncoder().encode(s);
+    const bin = String.fromCodePoint(...encoded);
+    return btoa(bin);
+}

ts/modules/login.ts

@@ -1,5 +1,5 @@
 import { Modal } from "../modules/modal.js";
-import { toggleLoader, _post } from "../modules/common.js";
+import { toggleLoader, _post, unicodeB64Encode } from "../modules/common.js";
 
 export class Login {
     loggedIn: boolean = false;
@@ -68,7 +68,7 @@ export class Login {
         const refresh = (username == "" && password == "");
         req.open("GET", this._url + (refresh ? "token/refresh" : "token/login"), true);
         if (!refresh) {
-            req.setRequestHeader("Authorization", "Basic " + btoa(username + ":" + password));
+            req.setRequestHeader("Authorization", "Basic " + unicodeB64Encode(username + ":" + password));
         }
         req.onreadystatechange = ((req: XMLHttpRequest, _: Event): any => {
             if (req.readyState == 4) {