import { initializeApp } from "firebase/app";
import { getAuth, GoogleAuthProvider } from "firebase/auth";

const requiredVars = [
  "VITE_FIREBASE_API_KEY",
  "VITE_FIREBASE_AUTH_DOMAIN",
  "VITE_FIREBASE_PROJECT_ID",
  "VITE_FIREBASE_STORAGE_BUCKET",
  "VITE_FIREBASE_MESSAGING_SENDER_ID",
  "VITE_FIREBASE_APP_ID",
] as const;

const missing = requiredVars.filter((key) => !import.meta.env[key]);

if (missing.length > 0) {
  throw new Error(
    `Faltan variables de entorno de Firebase. Revisa tu archivo .env.\nVariables faltantes: ${missing.join(", ")}`,
  );
}

const firebaseConfig = {
  apiKey: import.meta.env.VITE_FIREBASE_API_KEY,
  authDomain: import.meta.env.VITE_FIREBASE_AUTH_DOMAIN,
  projectId: import.meta.env.VITE_FIREBASE_PROJECT_ID,
  storageBucket: import.meta.env.VITE_FIREBASE_STORAGE_BUCKET,
  messagingSenderId: import.meta.env.VITE_FIREBASE_MESSAGING_SENDER_ID,
  appId: import.meta.env.VITE_FIREBASE_APP_ID,
};

export const app = initializeApp(firebaseConfig);
export const auth = getAuth(app);

export const googleProvider = new GoogleAuthProvider();
googleProvider.setCustomParameters({ prompt: "select_account" });