Tax is added directly to product for sale

Auth guard and auth service simplified and fixed so that user is updated upon login
Home component changed to use square buttons
Fixed showing the totals in the bill

ng linted the project

bookie/src/app/auth/auth.service.ts

@@ -1,10 +1,10 @@
 import { Injectable } from '@angular/core';
 import { HttpClient, HttpHeaders } from '@angular/common/http';
 import { Observable } from 'rxjs/internal/Observable';
-import { catchError, tap } from 'rxjs/operators';
-import { Subject } from 'rxjs/internal/Subject';
+import { catchError, map, tap } from 'rxjs/operators';
 import { ErrorLoggerService } from '../core/error-logger.service';
 import { User } from '../core/user';
+import { merge, Subject } from 'rxjs';
 
 
 const httpOptions = {
@@ -19,22 +19,18 @@ const checkUrl = '/v1/auth';
   providedIn: 'root'
 })
 export class AuthService {
-  public userObservable = new Subject<User>();
-
+  private readonly userSubject: Subject<User>;
+  private user: User;
+  public userObservable: Observable<User>;
   constructor(private http: HttpClient, private log: ErrorLoggerService) {
-    this.check().subscribe();
+    this.userSubject = new Subject<User>();
+    this.userObservable = merge(this.checkObserver(), this.userSubject).pipe(
+      tap(x => this.user = x)
+    );
   }
 
-  private _user: User;
-
-  get user() {
-    return this._user;
-  }
-
-  set user(user: User) {
-    this._user = user;
-    this.log.handleError('AuthService', 'Set User', user);
-    this.userObservable.next(user);
+  checkObserver(): Observable<User> {
+    return <Observable<User>>this.http.get<User>(checkUrl, httpOptions);
   }
 
   login(name: string, password: string, otp?: string, clientName?: string): Observable<any> {
@@ -49,29 +45,20 @@ export class AuthService {
 
     return this.http.post(loginUrl, data, httpOptions)
       .pipe(
-        tap((user: User) => this.user = user),
+        tap((user: User) => this.userSubject.next(user)),
         catchError(this.log.handleError('AuthService', 'login'))
       );
   }
 
-  logout(): Observable<any> {
-    return this.http.post(logoutUrl, {}, httpOptions)
+  logout(): Observable<boolean> {
+    return <Observable<boolean>>this.http.post<User>(logoutUrl, {}, httpOptions)
       .pipe(
-        tap((user: User) => this.user = user),
-        catchError(this.log.handleError('AuthService', 'logout'))
+        tap((user: User) => this.userSubject.next(user)),
+        map(() => true)
       );
   }
 
-  check(): Observable<any> {
-    return this.http.get(checkUrl, httpOptions)
-      .pipe(
-        tap((user: User) => this.user = user),
-        catchError(this.log.handleError('AuthService', 'check'))
-      );
-  }
-
-  hasPermission(permission: string) : boolean {
+  hasPermission(permission: string): boolean {
     return this.user !== undefined && this.user.isAuthenticated && this.user.perms.indexOf(permission) !== -1;
   }
-
 }