diff --git a/chatto/src/main/javascript/ts/src/model/ChatModel.ts b/chatto/src/main/javascript/ts/src/model/ChatModel.ts
index da7025b..e03caa3 100644
--- a/chatto/src/main/javascript/ts/src/model/ChatModel.ts
+++ b/chatto/src/main/javascript/ts/src/model/ChatModel.ts
@@ -3,162 +3,217 @@ import { Observer } from "../observe/Observer";
 import { JsonAPI } from "../singleton/JsonAPI";
 import { ChatMessageViewModel } from "../viewmodel/ChatMessageViewModel";
 import { ChatModelHelper } from "./ChatModelHelper";
-import log = require('loglevel');
+import log = require("loglevel");
 import { ObserverData } from "../observe/ObserverData";
 import { ActiveUserViewModel } from "../viewmodel/ActiveUserViewModel";
 import moment = require("moment");
 
 interface Params {
-    userName: string,
-    data: ChatMessageViewModel[],
-    op: string
+  userName: string;
+  data: ChatMessageViewModel[];
+  op: string;
 }
 
 export class ChatModel implements Subject<ChatMessageViewModel> {
-    /**
-  * @type {Observer[]} List of subscribers. In real life, the list of
-  * subscribers can be stored more comprehensively (categorized by event
-  * type, etc.).
-  */
-    private readonly _observers: Observer<ChatMessageViewModel>[] = [];
-    private readonly _messagePageMap: Map<string, number>;
-    private readonly _messagesMap: Map<string, ChatMessageViewModel[]>;
-    private readonly _chatModelHelper: ChatModelHelper;
-
-    constructor(chatModelHelper: ChatModelHelper) {
-        this._messagePageMap = new Map();
-        this._messagesMap = new Map();
-        this._chatModelHelper = chatModelHelper;
-    }
-    /**
-     * The subscription management methods.
-     */
-    public attach(observer: Observer<ChatMessageViewModel>): void {
-        log.info('Subject: Attached an observer.');
-        this._observers.push(observer);
+  /**
+   * @type {Observer[]} List of subscribers. In real life, the list of
+   * subscribers can be stored more comprehensively (categorized by event
+   * type, etc.).
+   */
+  private readonly _observers: Observer<ChatMessageViewModel>[] = [];
+  private readonly _messagePageMap: Map<string, number>;
+  private readonly _messagesMap: Map<string, ChatMessageViewModel[]>;
+  private readonly _chatModelHelper: ChatModelHelper;
+
+  constructor(chatModelHelper: ChatModelHelper) {
+    this._messagePageMap = new Map();
+    this._messagesMap = new Map();
+    this._chatModelHelper = chatModelHelper;
+  }
+  /**
+   * The subscription management methods.
+   */
+  public attach(observer: Observer<ChatMessageViewModel>): void {
+    log.info("Subject: Attached an observer.");
+    this._observers.push(observer);
+  }
+
+  public detach(observer: Observer<ChatMessageViewModel>): void {
+    const observerIndex = this._observers.indexOf(observer);
+    this._observers.splice(observerIndex, 1);
+    log.info("Subject: Detached an observer.");
+  }
+
+  private storeUserMessages(
+    username: string,
+    messages: ChatMessageViewModel[],
+    op: string
+  ) {
+    switch (op) {
+      case "clear":
+        this._messagesMap.set(username, []);
+        break;
+      case "page":
+        this._messagesMap.set(
+          username,
+          messages.concat(this.getStoredUserMessages(username))
+        );
+        break;
+      // case "page": this._messagesMap.set(username, messages);
+      case "new":
+        this._messagesMap.set(
+          username,
+          this.getStoredUserMessages(username).concat(messages)
+        );
+        break;
+      case "update":
+        this._messagesMap.set(
+          username,
+          this.getStoredUserMessages(username).concat(messages)
+        );
+        break;
+      default:
+        new Error("Invalid option");
     }
+  }
 
-    public detach(observer: Observer<ChatMessageViewModel>): void {
-        const observerIndex = this._observers.indexOf(observer);
-        this._observers.splice(observerIndex, 1);
-        log.info('Subject: Detached an observer.');
+  private getStoredUserMessages(username: string): ChatMessageViewModel[] {
+    let temp = this._messagesMap.get(username);
+    if (temp == null) return [];
+    else {
+      return temp;
     }
-
-    private storeUserMessages(username: string, messages: ChatMessageViewModel[], op: string) {
-        switch (op) {
-            case "clear": this._messagesMap.set(username, []); break;
-            case "page": this._messagesMap.set(username, messages.concat(this.getStoredUserMessages(username))); break;
-            // case "page": this._messagesMap.set(username, messages);
-            case "new": this._messagesMap.set(username, this.getStoredUserMessages(username).concat(messages)); break;
-            case "update": this._messagesMap.set(username, this.getStoredUserMessages(username).concat(messages)); break;
-            default: new Error("Invalid option");
+  }
+
+  /**
+   * Trigger an update in each subscriber.
+   */
+  public notify(p: Params): void {
+    log.info("Subject: Notifying observers...");
+    switch (p.op) {
+      case "clear":
+        {
+          const od: ObserverData<ChatMessageViewModel> = {
+            data: [],
+            op: "clear",
+          };
+          for (const observer of this._observers) {
+            observer.update(od);
+          }
         }
-
-    }
-
-    private getStoredUserMessages(username: string): ChatMessageViewModel[] {
-        let temp = this._messagesMap.get(username);
-        if (temp == null)
-            return [];
-        else {
-            return temp;
+        break;
+      case "new":
+        {
+          const od: ObserverData<ChatMessageViewModel> = {
+            data: p.data,
+            op: p.op,
+          };
+          for (const observer of this._observers) {
+            observer.update(od);
+          }
         }
-    }
-
-    /**
-     * Trigger an update in each subscriber.
-     */
-    public notify(p: Params): void {
-        log.info('Subject: Notifying observers...');
-        switch (p.op) {
-            case "clear": {
-                const od: ObserverData<ChatMessageViewModel> = { data: [], op: "clear" }
-                for (const observer of this._observers) {
-                    observer.update(od);
-                }
-            } break;
-            case "new": {
-                const od: ObserverData<ChatMessageViewModel> = { data: p.data, op: p.op }
-                for (const observer of this._observers) {
-                    observer.update(od);
-                }
-            } break;
-            case "page": {
-                const od: ObserverData<ChatMessageViewModel> = { data: p.data, op: p.op }
-                for (const observer of this._observers) {
-                    observer.update(od);
-                }
-            } break;
-            case "update": {
-                const od: ObserverData<ChatMessageViewModel> = { data: p.data, op: p.op }
-                for (const observer of this._observers) {
-                    observer.update(od);
-                }
-            } break;
-            default: { log.error("error") }
+        break;
+      case "page":
+        {
+          const od: ObserverData<ChatMessageViewModel> = {
+            data: p.data,
+            op: p.op,
+          };
+          for (const observer of this._observers) {
+            observer.update(od);
+          }
         }
+        break;
+      case "update":
+        {
+          const od: ObserverData<ChatMessageViewModel> = {
+            data: p.data,
+            op: p.op,
+          };
+          for (const observer of this._observers) {
+            observer.update(od);
+          }
+        }
+        break;
+      default: {
+        log.error("error");
+      }
     }
+  }
 
-    public someBusinessMethod(chatMessageList: ChatMessageViewModel[]): void {
-    }
+  public someBusinessMethod(chatMessageList: ChatMessageViewModel[]): void {}
 
-    public clear(): void {
-        log.info("Clearing model")
-        this._messagePageMap.set(JsonAPI.contactName!, 0);
-        this.storeUserMessages(JsonAPI.contactName!, Array(), "clear");
-        this.notify({ userName: "", data: [], op: "clear" })
-    }
+  public clear(): void {
+    log.info("Clearing model");
+    this._messagePageMap.set(JsonAPI.contactName!, 0);
+    this.storeUserMessages(JsonAPI.contactName!, Array(), "clear");
+    this.notify({ userName: "", data: [], op: "clear" });
+  }
 
-    public async getMessages(vm: ActiveUserViewModel, op: string): Promise<ChatMessageViewModel[]> {
-        if (this._messagePageMap.get(vm.userName!) == null)
-            this._messagePageMap.set(vm.userName!, 0);
-
-        const pageNumber = this._messagePageMap.get(vm.userName!)
-        const cVMs = await this._chatModelHelper.getMessages(vm.userName!, vm.passphrase, pageNumber!, vm.lastMessageTime!, op);
-        let cVMs2 = Array();
-        if (cVMs != null) {
-            log.info('Subject: My state has just changed')
-            const existingMessages = this.getStoredUserMessages(vm.userName!);
-            log.debug('existing message:')
-            log.debug(existingMessages);
-            log.debug('new messages:')
-            log.debug(cVMs);
-            cVMs2 = cVMs.filter(c => {
-                const res = existingMessages.filter(m => {
-                    if (moment(c.messageTime).isSame(moment(m.messageTime)))
-                        return true;
-                })
-                if (res.length > 0)
-                    return false;
-                return true;
-            })
-            if (cVMs2.length != 0 && op == "update") {
-                const lastMessageText = vm.lastMessageText = cVMs2[cVMs2.length - 1].message;
-                cVMs2.forEach(v => {
-                    if (v.userName == vm.userName) {
-                        v.lastMessageTime = cVMs2[cVMs2.length - 1].messageTime;
-                            v.lastMessageText = cVMs2[cVMs2.length - 1].message.slice(0, 15) + "..."
-                    }
-                })
-            };
-
-            if (cVMs2.length != 0 && op != "update") {
-
-                this._messagePageMap.set(vm.userName!, this._messagePageMap.get(vm.userName!)! + 1);
-            }
-
-            this.storeUserMessages(vm.userName!, cVMs2, op);
-            this.notify({ userName: vm.userName!, data: cVMs2, op: op });
-        }
-        else {
-            log.error('Messages were null');
-        }
-
-        return cVMs2;
+  public async getMessages(
+    aVm: ActiveUserViewModel,
+    op: string
+  ): Promise<ChatMessageViewModel[]> {
+    if (this._messagePageMap.get(aVm.userName!) == null)
+      this._messagePageMap.set(aVm.userName!, 0);
+
+    const pageNumber = this._messagePageMap.get(aVm.userName!);
+    const cVMs = await this._chatModelHelper.getMessages(
+      aVm.userName!,
+      aVm.passphrase,
+      pageNumber!,
+      aVm.lastMessageTime!,
+      op
+    );
+    let cVMsFiltered = Array<ChatMessageViewModel>();
+    if (cVMs != null && cVMs.length != 0) {
+      log.info("Subject: My state has just changed");
+      const existingMessages = this.getStoredUserMessages(aVm.userName!);
+      log.debug("existing message:");
+      log.debug(existingMessages);
+      log.debug("new messages:");
+      log.debug(cVMs);
+
+      // filter duplicates
+      cVMsFiltered = cVMs.filter((c) => {
+        const res = existingMessages.filter((m) => {
+          if (moment(c.messageTime).isSame(moment(m.messageTime))) return true;
+        });
+        if (res.length > 0) return false;
+        return true;
+      });
+
+      if (op == "update") {
+        //   update the active user last message text and times for each user
+        const lastMessage = cVMsFiltered[cVMsFiltered.length - 1];
+        cVMsFiltered.forEach((v) => {
+          if (v.fromUser == aVm.userName) {
+            aVm.lastMessageTime = lastMessage.messageTime;
+            aVm.lastMessageText = lastMessage.message.slice(0, 15) + "...";
+          }
+        });
+      } else {
+        this._messagePageMap.set(
+          aVm.userName!,
+          this._messagePageMap.get(aVm.userName!)! + 1
+        );
+      }
+
+      this.storeUserMessages(aVm.userName!, cVMsFiltered, op);
+      this.notify({ userName: aVm.userName!, data: cVMsFiltered, op: op });
     }
 
-    public async isPassphraseValid(passphrase: string, userName: string): Promise<boolean> {
-        let valid = await this._chatModelHelper.isPassphraseValid(passphrase, userName);
-        return valid;
-    }
-}
\ No newline at end of file
+    return cVMsFiltered;
+  }
+
+  public async isPassphraseValid(
+    passphrase: string,
+    userName: string
+  ): Promise<boolean> {
+    let valid = await this._chatModelHelper.isPassphraseValid(
+      passphrase,
+      userName
+    );
+    return valid;
+  }
+}