Refactor protocol assignment in getUrl method (#322)

Refactor the protocol determination logic to use bitwise operations for extracting protocol index. This change simplifies the code by directly using the lower four bits of the protocol to check for HTTP or HTTPS. Additionally, enhanced the error message formatting for better readability.

Author: pflynn-virtru

lib/src/nanotdf/models/ResourceLocator.ts

@@ -106,13 +106,15 @@ export default class ResourceLocator {
    * Construct URL from ResourceLocator or throw error
    */
   getUrl(): string | never {
-    let protocol;
-    if (this.protocol === ProtocolEnum.Http) {
+    let protocol: string;
+    // protocolIndex get the first four bits
+    const protocolIndex: number = this.protocol & 0xf;
+    if (protocolIndex === ProtocolEnum.Http) {
       protocol = 'http';
-    } else if (this.protocol === ProtocolEnum.Https) {
+    } else if (protocolIndex === ProtocolEnum.Https) {
       protocol = 'https';
     } else {
-      throw new Error(`Cannot create URL from protocol, ${ProtocolEnum[this.protocol]}`);
+      throw new Error(`Cannot create URL from protocol, "${ProtocolEnum[this.protocol]}"`);
     }
 
     return `${protocol}://${this.body}`;