firebase_admin.js

import admin from 'firebase-admin';
import dotenv from 'dotenv';
import { fileURLToPath } from 'url';
import { dirname, join } from 'path';

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);

// Load environment variables from current directory
dotenv.config();

// Validate required environment variables
const requiredEnvVars = [
  'FIREBASE_PROJECT_ID',
  'FIREBASE_PRIVATE_KEY_ID', 
  'FIREBASE_PRIVATE_KEY',
  'FIREBASE_CLIENT_EMAIL',
  'FIREBASE_CLIENT_ID',
  'FIREBASE_CLIENT_X509_CERT_URL'
];

for (const envVar of requiredEnvVars) {
  if (!process.env[envVar]) {
    throw new Error(`Missing required environment variable: ${envVar}`);
  }
}

// Create service account object from environment variables
const serviceAccount = {
  type: "service_account",
  project_id: process.env.FIREBASE_PROJECT_ID,
  private_key_id: process.env.FIREBASE_PRIVATE_KEY_ID,
  private_key: process.env.FIREBASE_PRIVATE_KEY.replace(/\\n/g, '\n'),
  client_email: process.env.FIREBASE_CLIENT_EMAIL,
  client_id: process.env.FIREBASE_CLIENT_ID,
  auth_uri: "https://accounts.google.com/o/oauth2/auth",
  token_uri: "https://oauth2.googleapis.com/token",
  auth_provider_x509_cert_url: "https://www.googleapis.com/oauth2/v1/certs",
  client_x509_cert_url: process.env.FIREBASE_CLIENT_X509_CERT_URL
};

admin.initializeApp({
  credential: admin.credential.cert(serviceAccount)
});

export default admin;