// public/js/firebase-init.js

export let app, db, auth, rtdb;
// Thêm export appId ở đây
export let appId, userId; //

export async function initializeFirebase() {
  console.log('Initializing Firebase...');
  const firebaseConfig = {
    apiKey: "AIzaSyAh3e5wBNfeQX5EO9DALjEQGXH9OrH3bUA",
    authDomain: "qlnb-web-app.firebaseapp.com",
    databaseURL: "https://qlnb-web-app-default-rtdb.asia-southeast1.firebasedatabase.app",
    projectId: "qlnb-web-app",
    storageBucket: "qlnb-web-app.firebasestorage.app",
    messagingSenderId: "871217970406",
    appId: "1:871217970406:web:6b3482a4efeaa869bccf27",
    measurementId: "G-FSGHYLQNSJ"
  };

  try {
    // Initialize Firebase app using compat namespace
    app = firebase.initializeApp(firebaseConfig);
    appId = firebaseConfig.appId; // Gán appId từ firebaseConfig

    // Get service instances using compat namespace
    db = firebase.firestore();
    auth = firebase.auth();
    rtdb = firebase.database();
    // Check if analytics is available before getting it
    // Use firebase.analytics() if available, otherwise skip
    if (firebase.analytics) {
       try {
          const analytics = firebase.analytics();
          console.log('Firebase Analytics initialized.');
       } catch (e) {
          console.warn('Firebase Analytics failed to initialize:', e);
       }
    } else {
       console.warn('Firebase Analytics SDK not available.');
    }

    console.log('Firebase initialized successfully.');
    // Remove the Auth state observer - This logic belongs in userManager.js
     console.log('Firebase initialization promise resolved.');
    return Promise.resolve();

  } catch (error) {
    console.error('Firebase initialization error:', error);
    return Promise.reject(error);
  }
}

// Call initializeFirebase() early in your main script (e.g., index.js)
// and await it before doing anything that depends on Firebase.