Initial commit

src/auth/AuthService.ts

@@ -0,0 +1,107 @@
+/**
+ * AuthService — device-based player authentication.
+ *
+ * Handles login via device ID (the primary auth flow for game clients),
+ * logout (token clearing), and auth state observation.
+ */
+
+import type { RudderContext } from '../core/context.js';
+import type { RemoteConfigShape } from '../state/RemoteConfigState.js';
+import { getOrCreateDeviceId } from '../device/DeviceId.js';
+import { api } from '../generated/api.js';
+import type { LoginViaDeviceResponse } from '../generated/auth.js';
+
+export type AuthState = 'signed-in' | 'signed-out';
+
+export type AuthStateListener = (state: AuthState) => void;
+
+export interface LoginWithDeviceOptions {
+  /** Player's region code (default: "global"). */
+  region?: string;
+  /** Player's language code (default: "en"). */
+  language?: string;
+  /** Optional player nickname; omitted from the request when not set. */
+  nickname?: string;
+}
+
+export class AuthService<TConfig extends RemoteConfigShape = RemoteConfigShape> {
+  private readonly listeners = new Set<AuthStateListener>();
+  private state: AuthState;
+
+  constructor(
+    private readonly ctx: RudderContext,
+    private readonly startRuntime: () => Promise<void>,
+    private readonly stopRuntime: () => void,
+  ) {
+    this.state = this.isAuthenticated ? 'signed-in' : 'signed-out';
+  }
+
+  /** True while an access token is present in the token store. */
+  get isAuthenticated(): boolean {
+    return this.ctx.options.tokenStore.getAccessToken() !== null;
+  }
+
+  /**
+   * Subscribes to auth state changes. The listener fires immediately with the
+   * current state (like `SyncedState.onChange`). Returns an unsubscribe function.
+   */
+  onAuthStateChange(listener: AuthStateListener): () => void {
+    this.listeners.add(listener);
+    // Resync with the token store — tokens may have been written externally
+    // since construction.
+    this.state = this.isAuthenticated ? 'signed-in' : 'signed-out';
+    listener(this.state);
+    return () => {
+      this.listeners.delete(listener);
+    };
+  }
+
+  /**
+   * Authenticates the current device and returns access + refresh tokens.
+   *
+   * The device ID is auto-generated on first call and persisted in localStorage.
+   * On success, tokens are saved to the client's TokenStore.
+   */
+  async loginWithDevice(options: LoginWithDeviceOptions = {}): Promise<LoginViaDeviceResponse> {
+    const { region = 'global', language = 'en', nickname } = options;
+    const response = await api.loginViaDevice(this.ctx, {
+      key: this.ctx.options.projectKey,
+      deviceId: getOrCreateDeviceId(),
+      region,
+      language,
+      nickname,
+    });
+
+    this.ctx.options.tokenStore.saveTokens(
+      response.accessToken ?? '',
+      response.refreshToken ?? '',
+    );
+    await this.startRuntime();
+    this.setState('signed-in');
+    return response;
+  }
+
+  /** Clears all stored tokens (logout). */
+  logout(): void {
+    this.ctx.options.tokenStore.clear();
+    this.stopRuntime();
+    this.setState('signed-out');
+  }
+
+  /**
+   * Called by the transport when the session is unrecoverable (refresh failed).
+   *
+   * @internal
+   */
+  notifySessionExpired(): void {
+    this.setState('signed-out');
+  }
+
+  private setState(state: AuthState): void {
+    if (state === this.state) return;
+    this.state = state;
+    for (const listener of this.listeners) {
+      listener(state);
+    }
+  }
+}