Reduce cognitive complexity

Author: hughns

src/rendezvous/MSC3906Rendezvous.ts

@@ -134,6 +134,10 @@ export class MSC3906Rendezvous {
         this._code = JSON.stringify(raw);
     }
 
+    /**
+     *
+     * @returns the checksum of the secure channel if the rendezvous set up was successful, otherwise undefined
+     */
     public async startAfterShowingCode(): Promise<string | undefined> {
         const checksum = await this.channel.connect();
 
@@ -157,6 +161,16 @@ export class MSC3906Rendezvous {
             protocols: [LOGIN_TOKEN_PROTOCOL.name],
         });
 
+        const receivedValidProtocolResponse = await this.waitForAndHandleProtocolPayload();
+
+        return receivedValidProtocolResponse ? checksum : undefined;
+    }
+
+    /**
+     *
+     * @returns true if the protocol was received successfully, false otherwise
+     */
+    private async waitForAndHandleProtocolPayload(): Promise<boolean> {
         logger.info("Waiting for other device to chose protocol");
         const { type, protocol, outcome, reason, intent } = await this.receive();
 
@@ -182,7 +196,7 @@ export class MSC3906Rendezvous {
                 reason = RendezvousFailureReason.Unknown;
             }
             await this.cancel(reason);
-            return undefined;
+            return false;
         }
 
         // v2 flow
@@ -206,28 +220,28 @@ export class MSC3906Rendezvous {
                     failureReason = RendezvousFailureReason.Unknown;
             }
             await this.cancel(failureReason);
-            return undefined;
+            return false;
         }
 
         // v1 unexpected payload
         if (this.v1FallbackEnabled && type !== PayloadType.Progress) {
             await this.cancel(RendezvousFailureReason.Unknown);
-            return undefined;
+            return false;
         }
 
         // v2 unexpected payload
         if (!this.v1FallbackEnabled && type !== PayloadType.Protocol) {
             await this.cancel(RendezvousFailureReason.Unknown);
-            return undefined;
+            return false;
         }
 
         // invalid protocol
         if (!protocol || !LOGIN_TOKEN_PROTOCOL.matches(protocol)) {
             await this.cancel(RendezvousFailureReason.UnsupportedAlgorithm);
-            return undefined;
+            return false;
         }
 
-        return checksum;
+        return true;
     }
 
     private async receive(): Promise<MSC3906RendezvousPayload> {