package com.example.sadmansakib.connectus.signup;

import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.AppCompatEditText;
import android.text.SpannableString;
import android.text.Spanned;
import android.text.TextPaint;
import android.text.method.LinkMovementMethod;
import android.text.style.ClickableSpan;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import com.example.sadmansakib.connectus.R;
import com.example.sadmansakib.connectus.login.LoginActivity;
import com.example.sadmansakib.connectus.model.Students;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.firestore.DocumentReference;
import com.google.firebase.firestore.FirebaseFirestore;

import java.util.Objects;

public class SignupActivity extends AppCompatActivity {

    private static final String TAG = "account_creator";
    FirebaseAuth mAuth;
    TextView textView;
    FirebaseFirestore db;
    AppCompatEditText first_name,last_name,std_id,user_email,user_password;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mAuth=FirebaseAuth.getInstance();
        setContentView(R.layout.activity_signup);
        textView=findViewById(R.id.link_create);
        first_name=findViewById(R.id.first_name);
        last_name=findViewById(R.id.last_name);
        db = FirebaseFirestore.getInstance();
        std_id=findViewById(R.id.input_student_id);
        user_email=findViewById(R.id.input_email_create);
        user_password=findViewById(R.id.input_password_create);
        setClickableString("Login here","Already have an account? Login here",textView);
    }

    /* reuse method from login activity */
    private void setClickableString(String clickableValue, String wholeValue, TextView textView) {
        SpannableString spannableString = new SpannableString(wholeValue);
        int startindex= wholeValue.indexOf(clickableValue);
        int endindex = startindex+clickableValue.length();
        spannableString.setSpan(new ClickableSpan() {
            @Override
            public void updateDrawState(@NonNull TextPaint ds) {
                super.updateDrawState(ds);
                ds.setUnderlineText(true);
            }
            @Override
            public void onClick(@NonNull View widget) {
                startActivity(new Intent(getApplicationContext(),
                        LoginActivity.class));
            }
        },startindex,endindex, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
        textView.setText(spannableString);
        textView.setMovementMethod(LinkMovementMethod.getInstance());
    }

    public void Signup(View view) {
        final String email = Objects.requireNonNull(user_email.getText()).toString();
        final String password = Objects.requireNonNull(user_password.getText()).toString();
        Log.d(TAG, "Signup: "+email);
        Log.d(TAG, "Signup: "+password);
        if (email.length() != 0 && password.length() != 0) {
            if(email.contains("@gmail.com") || email.contains("@outlook.com") || email.contains("@yahoo.com")){
                createAccount(email, password);
            }else{
                user_email.setError("Not a valid email address");
            }

        }else{
            user_email.setError("Email required");
            user_password.setError("password required");
        }
    }

    private void createAccount(String email, String password) {
        mAuth.createUserWithEmailAndPassword(email, password)
                .addOnCompleteListener(this, task -> {
                    if (task.isSuccessful()) {
                        // Sign in success, update UI with the signed-in user's information
                        Log.d(TAG, "createUserWithEmail:success");
                            FirebaseUser user = mAuth.getCurrentUser();
                            if(user!=null){
                                addStudentToData();
                                sendEmailVerification();
                            }
                    } else {
                        // If sign in fails, display a message to the user.
                        Log.e(TAG, "createUserWithEmail:failure", task.getException());
                        Toast.makeText(getApplicationContext(), "Authentication failed.",
                                Toast.LENGTH_SHORT).show();
                        updateUI();
                    }
                });
    }

    private void addStudentToData() {
        Students students= new Students(
                Objects.requireNonNull(first_name.getText()).toString(),
                Objects.requireNonNull(last_name.getText()).toString(),
                Objects.requireNonNull(user_email.getText()).toString(),
                Objects.requireNonNull(std_id.getText()).toString());
        db.collection("students")
                .document(Objects.requireNonNull(std_id.getText()).toString())
                .set(students)
                .addOnSuccessListener(aVoid ->
                        Toast.makeText(getApplicationContext(),
                                "User added to database!",
                                Toast.LENGTH_SHORT).show())
                .addOnFailureListener(failure ->
                        Toast.makeText(getApplicationContext(),
                                "database failed!",
                                Toast.LENGTH_SHORT).show());
    }


    private void sendEmailVerification() {
        FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
        assert user != null;

        user.sendEmailVerification().addOnCompleteListener(this, task -> {
            findViewById(R.id.btn_SignUp).setEnabled(true);
            if(task.isSuccessful()){
                Toast.makeText(getApplicationContext(),
                        "Verification email sent to " + user.getEmail(),
                        Toast.LENGTH_SHORT).show();
                FirebaseAuth.getInstance().signOut();
                startActivity(new Intent(getApplicationContext(),LoginActivity.class)
                        .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP));
                finish();
            } else {
                Log.e(TAG, "sendEmailVerification", task.getException());
                Toast.makeText(getApplicationContext(),
                        "Failed to send verification email.",
                        Toast.LENGTH_SHORT).show();
            }
        });
    }

    private void updateUI() {
        overridePendingTransition(0, 0);
        finish();
        overridePendingTransition(0, 0);
        startActivity(getIntent());
    }
}