var tempErrorCreds;
var tempProviderName;

// This is being called directly from unity.
function getSignInResults(successCallback, errorCallback) {
	firebase.auth().getRedirectResult().then(
		(result) => onFirebaseSignInSuccess(successCallback, errorCallback),
		(err) => onFirebaseSignInError(err, errorCallback));
}

// This is being called directly from unity.
function retrieveIdToken(successCallback, errorCallback) {
	if(firebase.auth().currentUser === null){
		if(errorCallback !== null) 
			errorCallback("User is null");
		return;
	}

	firebase.auth().currentUser.getIdToken().then(function (idToken) {
		var resultObj = {
			token: idToken,
			displayName: firebase.auth().currentUser.displayName
		};

		if (successCallback !== undefined) {

			successCallback(resultObj);
		}
	})
		.catch(function (error) {
			console.log(error);
			if (errorCallback !== undefined)
				errorCallback(error.message);
		});
}

function anonymousLogin(successCallback, errorCallback) {
	var resultObj = {
		token: "",
		displayName: "guest"
	};

	if (successCallback !== undefined) {

		successCallback(resultObj);
	}
}

/**
 * This is being called directly from unity.
 * Use firebase auth.
 * @param providerName for example - Google
 * @param successCallback
 * @param errorCallback
 * @param useRedirect Use redirect auth or popup. Redirect the page to google auth, or open a popup for the auth.
 * For the pc version (embedded browser) we use redirect, but for the webgl version we use a popup.
 */
function firebaseLogin(providerName, successCallback, errorCallback, useRedirect=false) {
	if (providerName === "anonymous") {
		anonymousLogin(successCallback, errorCallback);
		return;
	}

	var user = firebase.auth().currentUser;

	if(user != null && !user.isAnonymous){
		retrieveIdToken(successCallback, errorCallback);
		return;
	}

	var provider = getProvider(providerName);
	firebase.auth().useDeviceLanguage();
	
	if (useRedirect) {
		firebase.auth().signInWithRedirect(provider);
	}
	else {
		firebase.auth().signInWithPopup(provider)
			.then((result) => onFirebaseSignInSuccess(successCallback, errorCallback))
			.catch((err) => onFirebaseSignInError(err, errorCallback));
	}
}

function onFirebaseSignInSuccess (successCallback, errorCallback) {
	console.log("Successful sign in");
	retrieveIdToken(successCallback, errorCallback);
}

function onFirebaseSignInError(error, errorCallback) {
	// 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.
	tempErrorCreds = error.credential;
	console.log(error);

	if (errorCallback !== undefined)
		errorCallback(error.message);

	if (errorCode === 'auth/account-exists-with-different-credential') {
		// User's email already exists.
		// Get sign-in methods for this email.
		firebase.auth().fetchSignInMethodsForEmail(email).then(function (methods) {
			// the first method in the list will be the "recommended" method to use.
			if (methods.length == 0)
				return;
			// Sign in to provider.
			tempProviderName = methods[0].trim();
			setModalContent("generalModalContent",
				"<div id =\"continueWindow\"><span class=\"close\" id=\"closeButton\" onclick=\"hideModal('generalModal')\">&times;</span><p>Please press the button to login: </p><button onclick=\"continueLogin()\">Continue Login</button></div>");
			showModal("generalModal");
		});
	}
}

// This is being called directly from unity. 
function firebaseLogout() {
	firebase.auth().signOut().catch(function (error) {
		console.log(error);
	});
}

function getCurrentUserDisplayName() {
	var user = firebase.auth().currentUser;
	var displayName = "";
	if (user) {
		displayName = user.displayName;
	}
	return displayName;
}

function getProvider(providerName) {
	if (providerName && providerName.indexOf("facebook") != -1)
		return new firebase.auth.FacebookAuthProvider()
	else
		return new firebase.auth.GoogleAuthProvider()
}

function setModalContent(modalContentId, contentString) {
	content = document.getElementById(modalContentId);
	if (content) {
		content.innerHTML = contentString;
	}

}

function continueLogin() {
	hideModal("generalModal");
	var provider = getProvider(tempProviderName);
	firebase.auth().signInWithPopup(provider).then(
		function (result) {
			if (!tempErrorCreds) {
				return;
			}
			// As we have access to the pending credential, we can directly call the link method.
			result.user.linkAndRetrieveDataWithCredential(tempErrorCreds).then(function (usercred) {
				//goToApp();
			});
		});

}

function showModal(modalId) {
	modal = document.getElementById(modalId);
	if (modal)
		modal.style.display = "block";
}

function hideModal(modalId) {
	modal = document.getElementById(modalId);
	if (modal)
		modal.style.display = "none";
}