initial code commit

Downloader/tokenManager.js

@@ -0,0 +1,61 @@
+import fs from 'fs';
+import { google } from 'googleapis';
+
+
+export class tokenManager {
+    constructor({
+        clientId,
+        clientSecret,
+        redirectUri,
+        tokenPath = 'token.json'
+    }) {
+        // store options
+        this.clientId = clientId;
+        this.clientSecret = clientSecret;
+        this.redirectUri = redirectUri;
+        this.tokenPath = tokenPath;
+
+        // create oauth2 client
+        this.oauth2Client = new google.auth.OAuth2(
+            this.clientId,
+            this.clientSecret,
+            this.redirectUri
+        );
+    }
+
+    loadToken() {
+        if (!fs.existsSync(this.tokenPath)) {
+            return null;
+        }
+
+        const tokenData = fs.readFileSync(this.tokenPath, 'utf-8');
+        const token = JSON.parse(tokenData);
+        this.oauth2Client.setCredentials(token);
+
+        return token;
+    }
+
+    
+    saveToken(token) {
+        fs.writeFileSync(this.tokenPath, JSON.stringify(token, null, 2), 'utf-8');
+        this.oauth2Client.setCredentials(token);
+    }
+
+    async refreshAccessToken() {
+        // if no refresh token is present, we can't refresh
+        if (!this.oauth2Client.credentials.refresh_token) {
+            throw new Error('no refresh token is available');
+        }
+
+        // use the googleapis refresh method
+        const { credentials } = await this.oauth2Client.refreshAccessToken();
+
+        // save the new token info
+        this.saveToken(credentials);
+        return credentials;
+    }
+
+    getAuthClient() {
+        return this.oauth2Client;
+    }
+}