firebase.auth().languageCode = 'it';
// To apply the default browser preference instead of explicitly setting it.
// firebase.auth().useDeviceLanguage();
firebase
.auth()
.signInWithPopup(provider)
.then((result) => {
/** @type {firebase.auth.OAuthCredential} */
var credential = result.credential;
// The signed-in user info.
var user = result.user;
// This gives you a Facebook Access Token. You can use it to access the Facebook API.
var accessToken = credential.accessToken;
// ...
})
.catch((error) => {
// Handle Errors here.
var errorCode = error.code;
var errorMessage = error.message;
// The email of the user's account used.
var email = error.email;
// The firebase.auth.AuthCredential type that was used.
var credential = error.credential;
// ...
});
firebase.auth()
.getRedirectResult()
.then((result) => {
if (result.credential) {
/** @type {firebase.auth.OAuthCredential} */
var credential = result.credential;
// This gives you a Facebook Access Token. You can use it to access the Facebook API.
var token = credential.accessToken;
// ...
}
// The signed-in user info.
var user = result.user;
}).catch((error) => {
// Handle Errors here.
var errorCode = error.code;
var errorMessage = error.message;
// The email of the user's account used.
var email = error.email;
// The firebase.auth.AuthCredential type that was used.
var credential = error.credential;
// ...
});
// Step 1.
// User tries to sign in to Facebook.
auth.signInWithPopup(new firebase.auth.FacebookAuthProvider()).catch(function(error) {
// An error happened.
if (error.code === 'auth/account-exists-with-different-credential') {
// Step 2.
// User's email already exists.
// The pending Facebook credential.
var pendingCred = error.credential;
// The provider account's email address.
var email = error.email;
// Get sign-in methods for this email.
auth.fetchSignInMethodsForEmail(email).then(function(methods) {
// Step 3.
// If the user has several sign-in methods,
// the first method in the list will be the "recommended" method to use.
if (methods[0] === 'password') {
// Asks the user their password.
// In real scenario, you should handle this asynchronously.
var password = promptUserForPassword(); // TODO: implement promptUserForPassword.
auth.signInWithEmailAndPassword(email, password).then(function(result) {
// Step 4a.
return result.user.linkWithCredential(pendingCred);
}).then(function() {
// Facebook account successfully linked to the existing Firebase user.
goToApp();
});
return;
}
// All the other cases are external providers.
// Construct provider object for that provider.
// TODO: implement getProviderForProviderId.
var provider = getProviderForProviderId(methods[0]);
// At this point, you should let the user know that they already has an account
// but with a different provider, and let them validate the fact they want to
// sign in with this provider.
// Sign in to provider. Note: browsers usually block popup triggered asynchronously,
// so in real scenario you should ask the user to click on a "continue" button
// that will trigger the signInWithPopup.
auth.signInWithPopup(provider).then(function(result) {
// Remember that the user may have signed in with an account that has a different email
// address than the first one. This can happen as Firebase doesn't control the provider's
// sign in flow and the user is free to login using whichever account they own.
// Step 4b.
// Link to Facebook credential.
// As we have access to the pending credential, we can directly call the link method.
result.user.linkAndRetrieveDataWithCredential(pendingCred).then(function(usercred) {
// Facebook account successfully linked to the existing Firebase user.
goToApp();
});
});
});
}
});
function checkLoginState(response) {
if (response.authResponse) {
// User is signed-in Facebook.
var unsubscribe = firebase.auth().onAuthStateChanged((firebaseUser) => {
unsubscribe();
// Check if we are already signed-in Firebase with the correct user.
if (!isUserEqual(response.authResponse, firebaseUser)) {
// Build Firebase credential with the Facebook auth token.
var credential = firebase.auth.FacebookAuthProvider.credential(
response.authResponse.accessToken);
// Sign in with the credential from the Facebook user.
firebase.auth().signInWithCredential(credential)
.catch((error) => {
// Handle Errors here.
var errorCode = error.code;
var errorMessage = error.message;
// The email of the user's account used.
var email = error.email;
// The firebase.auth.AuthCredential type that was used.
var credential = error.credential;
// ...
});
} else {
// User is already signed-in Firebase with the correct user.
}
});
} else {
// User is signed-out of Facebook.
firebase.auth().signOut();
}
}
function isUserEqual(facebookAuthResponse, firebaseUser) {
if (firebaseUser) {
var providerData = firebaseUser.providerData;
for (var i = 0; i < providerData.length; i++) {
if (providerData[i].providerId === firebase.auth.FacebookAuthProvider.PROVIDER_ID &&
providerData[i].uid === facebookAuthResponse.userID) {
// We don't need to re-auth the Firebase connection.
return true;
}
}
}
return false;
}
// Sign in with the credential from the Facebook user.
firebase.auth().signInWithCredential(credential)
.then((result) => {
// Signed in
var credential = result.credential;
// ...
})
.catch((error) => {
// Handle Errors here.
var errorCode = error.code;
var errorMessage = error.message;
// The email of the user's account used.
var email = error.email;
// The firebase.auth.AuthCredential type that was used.
var credential = error.credential;
// ...
});
