package com.fishfriend.fishfriend;

import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.Toast;


import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;

public class SignInActivity extends AppCompatActivity {

    private EditText mEmail_editTxt;
    private EditText mPassword_editTxt;

    private Button mSignIn_btn;
    private Button mRegister_btn;
    private Button mBack_btn;

    private ProgressBar mProgress_bar;

    private FirebaseAuth mAuth;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_sign_in);
        mAuth = FirebaseAuth.getInstance();

        mEmail_editTxt = (EditText) findViewById(R.id.email_editText);
        mPassword_editTxt = (EditText) findViewById(R.id.password_editText);

        mSignIn_btn = (Button) findViewById(R.id.signin_btn);
        mRegister_btn = (Button) findViewById(R.id.register_btn);
        mBack_btn = (Button) findViewById(R.id.login);

        mProgress_bar = (ProgressBar) findViewById(R.id.loading_progressBar);

        mSignIn_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(isEmpty()) return;
                inProgress(true);
                mAuth.signInWithEmailAndPassword(mEmail_editTxt.getText().toString(),
                        mPassword_editTxt.getText().toString())
                        .addOnSuccessListener(new OnSuccessListener<AuthResult>() {
                            @Override
                            public void onSuccess(AuthResult authResult) {
                                Toast.makeText(SignInActivity.this, "User signed in",
                                        Toast.LENGTH_LONG).show();
                                Intent intent = new Intent(SignInActivity.this, MainActivity.class);
                                intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                                startActivity(intent);
                                finish(); return;

                            }
                        }).addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        inProgress(false);
                        Toast.makeText(SignInActivity.this, "Sign in failed!"+e.getMessage(), Toast.LENGTH_SHORT).show();
                    }
                });
            }
        });

        mRegister_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(isEmpty()) return;
                inProgress(true);
                mAuth.createUserWithEmailAndPassword(mEmail_editTxt.getText().toString(),
                        mPassword_editTxt.getText().toString())
                        .addOnSuccessListener(new OnSuccessListener<AuthResult>() {
                            @Override
                            public void onSuccess(AuthResult authResult) {
                                Toast.makeText(SignInActivity.this, "User registered successfully!",
                                        Toast.LENGTH_LONG).show();
                                inProgress(false);
                            }
                        }).addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        inProgress(false);
                        Toast.makeText(SignInActivity.this, "Registration failed."+e.getMessage(), Toast.LENGTH_SHORT).show();
                    }
                });

            }
        });

        mBack_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                finish(); return;
            }
        });

    }

    private void inProgress(boolean x){
        if(x){
            mProgress_bar.setVisibility(View.VISIBLE);
            mBack_btn.setEnabled(false);
            mSignIn_btn.setEnabled(false);
            mRegister_btn.setEnabled(false);
        }else{
            mProgress_bar.setVisibility(View.GONE);
            mBack_btn.setEnabled(true);
            mSignIn_btn.setEnabled(true);
            mRegister_btn.setEnabled(true);
        }
    }

    private boolean isEmpty(){
        if(TextUtils.isEmpty(mEmail_editTxt.getText().toString())){
            mEmail_editTxt.setError("REQUIRED!");
            return true;
        }
        if(TextUtils.isEmpty(mPassword_editTxt.getText().toString())){
            mPassword_editTxt.setError("REQUIRED!");
            return true;
        }
        return false;
    }

}






<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".SignInActivity">

    <EditText
        android:id="@+id/email_editText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:ems="10"
        android:hint="e-mail address"
        android:inputType="textEmailAddress"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/password_editText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:ems="10"
        android:hint="password"
        android:inputType="textPassword"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/email_editText" />

    <Button
        android:id="@+id/signin_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:text="SIGN IN"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/password_editText" />

    <Button
        android:id="@+id/register_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:text="REGISTER"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/signin_btn" />

    <Button
        android:id="@+id/login"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:text="BACK"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/register_btn" />

    <ProgressBar
        android:id="@+id/loading_progressBar"
        style="?android:attr/progressBarStyle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:visibility="invisible"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/login" />
</android.support.constraint.ConstraintLayout>