Help Gist for https://devbest.com/threads/jquery-ajax-return-value.83811

database.php

<?php
$db_host = 'localhost';
$db_name = 'testdb';
$db_charset = 'utf8mb4';
$db_username = 'root';
$db_password = '';

try {
  $db = new PDO('mysql:host='.$db_host.';dbname='.$db_name.';charset='.$db_charset, $db_username, $db_password);
  $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
  $db->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
} catch(PDOException $e) {
 die($e->getMessage()); 
}

login.js

$('#btn-login').click(function() {
  var username = $('#login-username').val(); 
  var password = $('#login-password').val(); 
  
  new PNotify({
    title: 'Processing...',
    text: 'Logging you in...',
    type: 'info'
  });
  
  $.ajax({
    url : 'system/js/login.php', 
    method: 'POST',
    data: {
      username: username,
      password: password
    }
  }).done(function(res) {
    new PNotify({
      title : 'Success!', 
      text: 'Logged in! Redirecting in a moment...',
      type:'success'
    });
    
    setTimeout(function() { 
      window.location.href = 'index.php'; 
    }, 2000);
  }).fail(function(err) {
    switch (err) {
      case 'username':
        return new PNotify({
          title: 'Invalid credentials!',
          text: "User doesn't exist!",
          type: 'error'
        }); 
      case 'password':
        return new PNotify({
          title: 'Invalid credentials!',
          text: 'Password is incorrect!',
          type: 'error'
        }); 
      default:
        return new PNotify({
          title: 'Error Occurred',
          text: 'An error occurred! Please contact the webmaster.',
          type: 'error'
        });
    }
  });

login.php

<?php
if (isset($_POST['username']) && isset($_POST['password'])) {
  include('./database.php');
  
  $username = $_POST['username'];
  $password = $_POST['password'];
  
  $stmt = $db->prepare('SELECT `password` FROM `users` WHERE `username` = :u');
  $stmt->bindParam(':u', $username, PDO::PARAM_STR);
  $stmt->execute();
  
  if ($stmt->rowCount() > 0) {
    $db_password = $stmt->fetchColumn();
    
    if (password_verify($password, $db_password) {
      exit('success');
    } else {
      http_response_code(401);
      exit('password');
    }
  } else {
    http_response_code(401);
    exit('username');
  }
} else {
  http_response_code(403);
  exit('error here that doesnt really matter');
}

register.js

$('#btn-signup').click(function(){
  var reg_username = $('#reg_username').val(); 
  var reg_pass = $('#reg_pass').val();
  var reg_r_pass = $('#reg_r_pass').val();
  
  new PNotify({
    title: 'Registering...',
    text: 'Sending data to database...', 
    type: 'info'
  });
  
  $.ajax({
    url : 'system/js/register.php',
    method: 'POST',
    data: {
      username: reg_username,
      password: reg_pass,
      password_confirm: reg_r_pass
    }
  }).done(function(res) {
    return new PNotify({
      title: 'Registered!',
      text: 'You are registered successfully. For security reasons, please log in with your credentials..',
      type: 'success'
    }); 
  }).fail(function(err) {
    switch (err) {
      case 'password': 
        return new PNotify({
          title: 'Your passwords are incorrect!',
          text: 'Your passwords do not match... Check them carefully!',
          type: 'error'
        }); 
      case 'username':
        return new PNotify({
          title: 'Your username is incorrect!',
          text: 'Your username is taken... Please choose another one! ',
          type: 'error'
        }); 
      default:
        return new PNotify({
          title: 'Error Occurred',
          text: 'An error occurred! Please contact the webmaster.',
          type: 'error'
        });
    }
  });

register.php

<?php
if (isset($_POST['username']) && isset($_POST['password']) && isset($_POST['password_confirm'])) {
  $username = $_POST['username'];
  $password = $_POST['password'];
  $password_confirm = $_POST['password_confirm'];
  
  if ($password === $password_confirm) {
    include('./database.php');
    
    $stmt = $db->prepare('SELECT `id` FROM `users` WHERE `username` = :u');
    $stmt->bindParam(':u', $username, PDO::PARAM_STR);
    $stmt->execute();

    if ($stmt->rowCount() < 1) {
      $hashed_password = password_hash($password, PASSWORD_DEFAULT);

      $stmt = $db->prepare('INSERT INTO `users` (`username`, `password`) VALUES (:u, :p)');
      $stmt->bindParam(':u', $username, PDO::PARAM_STR);
      $stmt->bindParam(':p', $hashed_password, PDO::PARAM_STR);
      $stmt->execute();

      // No reason to use http_response_code as it's automatically set to 200 for OK
      exit('success');
    } else {
      http_response_code(403);
      exit('username');
    }
  } else {
    http_response_code(403);
    exit('password');
  }
} else {
  http_response_code(405); 
  exit('random shit here that doesnt really matter');
}

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