EnterActivity [Firebase]

package com.soyalab.askaruly.lor;

import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import com.facebook.CallbackManager;
import com.facebook.FacebookCallback;
import com.facebook.FacebookException;
import com.facebook.login.LoginResult;
import com.facebook.login.widget.LoginButton;
import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.auth.api.signin.GoogleSignInResult;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthCredential;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.auth.GoogleAuthProvider;

public class EnterActivity extends AppCompatActivity {

    SignInButton googleButton;
    FirebaseAuth mAuth;
    LoginButton fbButton;
    TextView loginStatus;
    CallbackManager callbackManager;

    private final static int RC_SIGN_IN = 2;
    GoogleApiClient mGoogleApiClient;
    FirebaseAuth.AuthStateListener mAuthListener;

    @Override
    protected void onStart() {
        super.onStart();

        mAuth.addAuthStateListener(mAuthListener);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_enter);

        fbButton = (LoginButton)findViewById(R.id.fbBtn);
        googleButton = (SignInButton)findViewById(R.id.googleBtn);
        loginStatus = (TextView)findViewById(R.id.loginStatus);

        callbackManager = CallbackManager.Factory.create();
        fbButton.registerCallback(callbackManager, new FacebookCallback<LoginResult>() {
            @Override
            public void onSuccess(LoginResult loginResult) {
                loginStatus.setText("Login Success\n" + loginResult.getAccessToken().getUserId());
                /*startActivity(new Intent(EnterActivity.this,MainActivity.class));*/
                startActivity(new Intent(EnterActivity.this,LoginActivity.class));
            }

            @Override
            public void onCancel() {
                loginStatus.setText("Login cancelled");
            }

            @Override
            public void onError(FacebookException error) {

            }
        });

        mAuth = FirebaseAuth.getInstance();

        googleButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                signIn();
            }
        });

        mAuthListener = new FirebaseAuth.AuthStateListener() {
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                if (firebaseAuth.getCurrentUser() != null) {
                    /*startActivity(new Intent(EnterActivity.this,MainActivity.class));*/
                    startActivity(new Intent(EnterActivity.this,LoginActivity.class));
                }
            }
        };

        // Configure Google Sign In
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestIdToken(getString(R.string.default_web_client_id))
                .requestEmail()
                .build();

        // Build a GoogleApiClient with access to the Google Sign-In API and the
// options specified by gso.
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .enableAutoManage(this /* FragmentActivity */, new GoogleApiClient.OnConnectionFailedListener() {
                    @Override
                    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
                        Toast.makeText(EnterActivity.this, "Something went wrong",Toast.LENGTH_SHORT).show();
                    }
                })
                .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
                .build();
    }

    private void signIn() {
        Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
        startActivityForResult(signInIntent, RC_SIGN_IN);
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        // Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
            if (result.isSuccess()) {
                // Google Sign In was successful, authenticate with Firebase
                GoogleSignInAccount account = result.getSignInAccount();
                firebaseAuthWithGoogle(account);
            } else {
                // Google Sign In failed, update UI appropriately
                // ...
                Toast.makeText(EnterActivity.this, "Auth went wrong",Toast.LENGTH_SHORT).show();
            }
        }
    }

    private void firebaseAuthWithGoogle(GoogleSignInAccount account) {
        AuthCredential credential = GoogleAuthProvider.getCredential(account.getIdToken(), null);
        mAuth.signInWithCredential(credential)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            // Sign in success, update UI with the signed-in user's information
                            Log.d("TAG", "signInWithCredential:success");
                            FirebaseUser user = mAuth.getCurrentUser();
                            //updateUI(user);
                        } else {
                            // If sign in fails, display a message to the user.
                            Log.w("TAG", "signInWithCredential:failure", task.getException());
                            Toast.makeText(EnterActivity.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                            //updateUI(null);
                        }

                        // ...
                    }
                });
    }
}