feat: add GitHub OAuth2 authentication support

frontend/src/app/service/auth.service.ts

@@ -1,7 +1,7 @@
 import { Injectable } from '@angular/core';
 import { HttpClient } from '@angular/common/http';
 import { BehaviorSubject, Observable, tap } from 'rxjs';
-import { Router } from '@angular/router';
+import { Router, ActivatedRoute } from '@angular/router';
 import { LoginRequest } from '../model/auth/LoginRequest';
 import { RegisterRequest } from '../model/auth/RegisterRequest';
 import { AuthResponse } from '../model/auth/AuthResponse';
@@ -17,20 +17,41 @@ const USER_KEY = 'user';
 export class AuthService {
   private authUrl = `${environment.apiUrl}/auth`;
   private userUrl = `${environment.apiUrl}/users`;
+  private oauthUrl = `${environment.apiUrl}/oauth2`;
 
   userSubject: BehaviorSubject<User | null>;
 
   constructor(
     private http: HttpClient,
-    private router: Router
+    private router: Router,
+    private route: ActivatedRoute
   ) {
     this.userSubject = new BehaviorSubject<User | null>(this.getUserFromStorage());
 
+    // Check for token in URL (OAuth callback) on initialization
+    this.route.queryParams.subscribe(params => {
+      const token = params['token'];
+      if (token) {
+        this.handleOAuthCallback(token);
+      }
+    });
+
     if (this.getToken()) {
       this.loadCurrentUser();
     }
   }
 
+  private handleOAuthCallback(token: string): void {
+    this.setToken(token);
+    this.loadCurrentUser();
+    // Clean up the URL by removing the token
+    this.router.navigate([], {
+      relativeTo: this.route,
+      queryParams: {},
+      replaceUrl: true
+    });
+  }
+
   public get currentUserValue(): User | null {
     return this.userSubject.value;
   }
@@ -48,6 +69,16 @@ export class AuthService {
     return this.http.post<User>(`${this.authUrl}/register`, registerRequest);
   }
 
+  githubAuth(code: string): Observable<AuthResponse> {
+    return this.http.post<AuthResponse>(`${this.oauthUrl}/github/callback`, { code }).pipe(
+      tap((response) => {
+        console.log(response.token);
+        this.setToken(response.token);
+        this.loadCurrentUser();
+      })
+    );
+  }
+
   logout(): void {
     localStorage.removeItem(TOKEN_KEY);
     localStorage.removeItem(USER_KEY);