feat: replace browser login with imported Reddit sessions

src/services/reddit-session-importer.ts

@@ -0,0 +1,48 @@
+import type { Cookie } from 'playwright';
+import type { MatrixClient } from './chat/matrix/client.js';
+import type { MatrixCredentials } from './chat/matrix/types.js';
+
+interface BrowserSessionTarget {
+  importRedditCookies(cookies: Cookie[]): Promise<void>;
+  isSessionValid(): Promise<boolean>;
+}
+
+interface ChatSessionTarget {
+  setMatrixClient(client: MatrixClient): void;
+}
+
+type MatrixClientFactory = (credentials: MatrixCredentials) => MatrixClient;
+type CredentialStore = (credentials: MatrixCredentials) => void;
+
+export class RedditSessionImporter {
+  constructor(
+    private readonly browser: BrowserSessionTarget,
+    private readonly chat: ChatSessionTarget,
+    private readonly createMatrixClient: MatrixClientFactory,
+    private readonly saveCredentials: CredentialStore,
+  ) {}
+
+  async import(cookies: Cookie[], credentials: MatrixCredentials): Promise<void> {
+    const homeserver = new URL(credentials.homeserver);
+    if (
+      homeserver.protocol !== 'https:' ||
+      !/^matrix\.(?:redditspace|reddit)\.com$/i.test(homeserver.hostname)
+    ) {
+      throw new Error('Invalid Reddit Matrix homeserver');
+    }
+
+    const matrixClient = this.createMatrixClient(credentials);
+    const userId = await matrixClient.whoami();
+    if (!userId || userId !== credentials.userId) {
+      throw new Error('Matrix credentials did not verify the exported account');
+    }
+
+    await this.browser.importRedditCookies(cookies);
+    if (!(await this.browser.isSessionValid())) {
+      throw new Error('Imported cookies did not authenticate with Reddit');
+    }
+
+    this.saveCredentials(credentials);
+    this.chat.setMatrixClient(matrixClient);
+  }
+}