package com.example.lewis.thinktankv10;

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.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;

public class Login extends AppCompatActivity {

    protected FirebaseAuth mAuth;
    protected FirebaseAuth.AuthStateListener mAuthListener;
    protected final static String TAG = "LoginActivity";

    private EditText etEmail;
    private EditText etPass;
    private Button bLogin;
    private Button bRegister;

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

        etEmail = (EditText)findViewById(R.id.editText_Email);
        etPass = (EditText)findViewById(R.id.editText_Password);
        bLogin = (Button)findViewById(R.id.Login_Button);
        bRegister = (Button)findViewById(R.id.Register_Button);

        bRegister.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(Login.this, Register.class);
                startActivity(intent);
            }
        });

        bLogin.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                login(etEmail.getText().toString(), etPass.getText().toString());
            }
        });

        mAuth = FirebaseAuth.getInstance();

        mAuthListener = new FirebaseAuth.AuthStateListener() {
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                FirebaseUser user = firebaseAuth.getCurrentUser();
                if (user!=null) {
                    Log.d(TAG, "onAuthStateChanged:successful_login: " + user.getUid());
                }
                else {
                    Log.d(TAG, "onAuthStateChanged:successful_logout");
                }
            }
        };
    }

    @Override
    public void onStart() {
        super.onStart();
        mAuth.addAuthStateListener(mAuthListener);
    }

    @Override
    public void onStop() {
        super.onStop();
        if (mAuthListener != null) {
            mAuth.removeAuthStateListener(mAuthListener);
        }
    }

    private void login(String email, String pass) {
        Log.d(TAG, "user signed in: " + email);
        if (validateLoginForm() == false) {
            return;
        }

        mAuth.signInWithEmailAndPassword(email, pass).addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
            @Override
            public void onComplete(@NonNull Task<AuthResult> task) {
                Log.d(TAG, "successful login: " + task.isSuccessful());

                if(task.isSuccessful() == false) {
                    Log.w(TAG, "login unsuccessful: " + task.getException());

                    Toast.makeText(Login.this, "Email or password was not recognised", Toast.LENGTH_SHORT).show();
                    return;
                }
                Intent intent = new Intent(Login.this, MainMenu.class);
                startActivity(intent);

            }
        });


    }

    private boolean validateLoginForm() {
        boolean valid = true;

        String email = etEmail.getText().toString();
        if (TextUtils.isEmpty(email)) {
            etEmail.setError("Required");
            valid = false;
        } else {
            etEmail.setError(null);
        }

        String password = etPass.getText().toString();
        if (TextUtils.isEmpty(password)) {
            etPass.setError("Required");
            valid = false;
        } else {
            etPass.setError(null);
        }

        return valid;
    }

}