Process username changes in storage service

ts/util/getTitle.ts

@@ -36,7 +36,7 @@ export function getTitleNoDefault(
 
   return (
     (isShort ? attributes.systemGivenName : undefined) ||
-    attributes.name ||
+    getSystemName(attributes) ||
     (isShort ? attributes.profileName : undefined) ||
     getProfileName(attributes) ||
     getNumber(attributes) ||
@@ -44,6 +44,30 @@ export function getTitleNoDefault(
   );
 }
 
+// Note that the used attributes field should match the ones we listen for
+// change on in ConversationModel (see `ConversationModel#maybeClearUsername`)
+export function canHaveUsername(
+  attributes: Pick<
+    ConversationAttributesType,
+    'id' | 'type' | 'name' | 'profileName' | 'profileFamilyName' | 'e164'
+  >,
+  ourConversationId: string | undefined
+): boolean {
+  if (!isDirectConversation(attributes)) {
+    return false;
+  }
+
+  if (ourConversationId === attributes.id) {
+    return true;
+  }
+
+  return (
+    !getSystemName(attributes) &&
+    !getProfileName(attributes) &&
+    !getNumber(attributes)
+  );
+}
+
 export function getProfileName(
   attributes: Pick<
     ConversationAttributesType,
@@ -57,6 +81,22 @@ export function getProfileName(
   return undefined;
 }
 
+export function getSystemName(
+  attributes: Pick<
+    ConversationAttributesType,
+    'systemGivenName' | 'systemFamilyName' | 'type'
+  >
+): string | undefined {
+  if (isDirectConversation(attributes)) {
+    return combineNames(
+      attributes.systemGivenName,
+      attributes.systemFamilyName
+    );
+  }
+
+  return undefined;
+}
+
 export function getNumber(
   attributes: Pick<ConversationAttributesType, 'e164' | 'type'>
 ): string {