created auth system

src/app/services/auth.service.ts

@@ -0,0 +1,128 @@
+import { Injectable, signal, computed } from '@angular/core';
+import { HttpClient } from '@angular/common/http';
+import { Observable, of, catchError, map, tap } from 'rxjs';
+import { AuthSession, AuthStatus } from '../models/auth.model';
+import { environment } from '../../environments/environment';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class AuthService {
+  private sessionSignal = signal<AuthSession | null>(null);
+  private statusSignal = signal<AuthStatus>('unknown');
+  private showLoginSignal = signal(false);
+
+  /** Current auth session */
+  readonly session = this.sessionSignal.asReadonly();
+  /** Current auth status */
+  readonly status = this.statusSignal.asReadonly();
+  /** Whether user is fully authenticated */
+  readonly isAuthenticated = computed(() => this.statusSignal() === 'authenticated');
+  /** Whether to show login dialog */
+  readonly showLoginDialog = this.showLoginSignal.asReadonly();
+  /** Display name of authenticated user */
+  readonly displayName = computed(() => this.sessionSignal()?.displayName ?? null);
+
+  private readonly apiUrl = environment.apiUrl;
+  private sessionCheckTimer?: ReturnType<typeof setInterval>;
+
+  constructor(private http: HttpClient) {
+    // On init, check existing session via cookie
+    this.checkSession();
+  }
+
+  /**
+   * Check current session status with backend.
+   * The backend reads the session cookie and returns the session info.
+   */
+  checkSession(): void {
+    this.statusSignal.set('checking');
+
+    this.http.get<AuthSession>(`${this.apiUrl}/auth/session`, {
+      withCredentials: true
+    }).pipe(
+      catchError(() => {
+        this.statusSignal.set('unauthenticated');
+        this.sessionSignal.set(null);
+        return of(null);
+      })
+    ).subscribe(session => {
+      if (session && session.active) {
+        this.sessionSignal.set(session);
+        this.statusSignal.set('authenticated');
+        this.scheduleSessionRefresh(session.expiresAt);
+      } else if (session && !session.active) {
+        this.sessionSignal.set(null);
+        this.statusSignal.set('expired');
+      } else {
+        this.statusSignal.set('unauthenticated');
+      }
+    });
+  }
+
+  /**
+   * Called after user completes Telegram login.
+   * The callback URL from Telegram will hit our backend which sets the cookie.
+   * Then we re-check the session.
+   */
+  onTelegramLoginComplete(): void {
+    this.checkSession();
+    this.hideLogin();
+  }
+
+  /** Generate the Telegram login URL for bot-based auth */
+  getTelegramLoginUrl(): string {
+    const botUsername = (environment as Record<string, unknown>)['telegramBot'] as string || 'dexarmarket_bot';
+    const callbackUrl = encodeURIComponent(`${this.apiUrl}/auth/telegram/callback`);
+    return `https://t.me/${botUsername}?start=auth_${callbackUrl}`;
+  }
+
+  /** Get QR code data URL for Telegram login */
+  getTelegramQrUrl(): string {
+    return this.getTelegramLoginUrl();
+  }
+
+  /** Show login dialog (called when user tries to pay without being logged in) */
+  requestLogin(): void {
+    this.showLoginSignal.set(true);
+  }
+
+  /** Hide login dialog */
+  hideLogin(): void {
+    this.showLoginSignal.set(false);
+  }
+
+  /** Logout — clears session on backend and locally */
+  logout(): void {
+    this.http.post(`${this.apiUrl}/auth/logout`, {}, {
+      withCredentials: true
+    }).pipe(
+      catchError(() => of(null))
+    ).subscribe(() => {
+      this.sessionSignal.set(null);
+      this.statusSignal.set('unauthenticated');
+      this.clearSessionRefresh();
+    });
+  }
+
+  /** Schedule a session re-check before it expires */
+  private scheduleSessionRefresh(expiresAt: string): void {
+    this.clearSessionRefresh();
+
+    const expiresMs = new Date(expiresAt).getTime();
+    const nowMs = Date.now();
+    // Re-check 60 seconds before expiry, minimum 30s from now
+    const refreshIn = Math.max(expiresMs - nowMs - 60_000, 30_000);
+
+    this.sessionCheckTimer = setTimeout(() => {
+      this.checkSession();
+    }, refreshIn);
+  }
+
+  private clearSessionRefresh(): void {
+    if (this.sessionCheckTimer) {
+      clearTimeout(this.sessionCheckTimer);
+      this.sessionCheckTimer = undefined;
+    }
+  }
+}