Move getFriendlyRoomName to Room. Add recalculate() function to cache info.

lib/models/room.js

@@ -3,6 +3,8 @@
  * @module models/room
  */
 var RoomState = require("./room-state");
+var RoomSummary = require("./room-summary");
+var utils = require("../utils");
 
 /**
  * Construct a new Room.
@@ -43,6 +45,62 @@ Room.prototype = {
                 this.timeline.push(events[i]);
             }
         }
+    },
+
+    /**
+     * Recalculate various aspects of the room, including the room name and
+     * room summary. Call this any time the room's current state is modified.
+     * @param {string} userId The client's user ID.
+     */
+    recalculate: function(userId) {
+        this.name = this.calculateRoomName(userId);
+        this.summary = new RoomSummary(this.roomId, {
+            title: this.name
+        });
+    },
+
+    /**
+     * Calculates the name of the room from the current room state.
+     * @param {string} userId The client's user ID. Used to filter room members
+     * correctly.
+     * @return {string} The calculated room name.
+     */
+    calculateRoomName: function(userId) {
+        // check for an alias, if any. for now, assume first alias is the
+        // official one.
+        var alias;
+        var mRoomAliases = this.currentState.getStateEvents("m.room.aliases")[0];
+        if (mRoomAliases && utils.isArray(mRoomAliases.getContent().aliases)) {
+            alias = mRoomAliases.getContent().aliases[0];
+        }
+
+        var mRoomName = this.currentState.getStateEvents('m.room.name', '');
+        if (mRoomName) {
+            return mRoomName.getContent().name + (alias ? " (" + alias + ")" : "");
+        }
+        else if (alias) {
+            return alias;
+        }
+        else {
+            var members = this.currentState.getMembers();
+
+            if (members.length === 0) {
+                return "Unknown";
+            }
+            else if (members.length == 1) {
+                return members[0].name;
+            }
+            else if (members.length == 2) {
+                return (
+                    members[0].name + " and " + members[1].name
+                );
+            }
+            else {
+                return (
+                    members[0].name + " and " + (members.length - 1) + " others"
+                );
+            }
+        }
     }
 };