<?php

require_once "conn.php";

// Error initialization
$globalError = "";
$usernameError = "";
$passwordError = "";

$usernameMinLength = 5;
$usernameMaxLength = 60;
$passwordMinLength = 8;
$passwordMaxLength = 64;

// Function used to clear strings from special chars
function clear_string($str)
{
    $str = str_replace(' ', '-', $str);
    return preg_replace('/[^A-Za-z0-9\-]/', '', $str);
}

if(isset($_POST['name']) && $_POST['name'] != "") // Checking if there is username input
{
    if(strlen ($_POST['name']) >= $usernameMinLength && strlen ($_POST['name']) <= $usernameMaxLength) // Check username length criteria
    {
		if(isset($_SESSION['username'])) // Dont allow register if user is already logged in
	    {
		    $globalError = "Already registered, please <b>Logout</b> to register a new <b>User</b>";
    	}
    	else // If user is NOT logged in , then allow register
    	{
	       if($_POST['name'] == clear_string($_POST['name'])) // Check if username contains special characters, if username = stripped username, then continue, otherwise give error
 	       {
                if(strlen ($_POST['password']) >= $passwordMinLength && strlen ($_POST['password']) <= $passwordMaxLength) // Check if password is long enough
	    		{
					{ // Check if username exists
					    $sql = "SELECT username FROM users";
                        $result = $conn->query($sql);
                        if ($result->num_rows > 0)
					    {
						    $usernameError = "Username is <b>Already</b> taken!";
					    }
					}
	 	            $hashPassword = hash('sha256', $_POST['password']); // Hash the input passoword

	 	            $sql = "INSERT INTO users (username, password)
                    VALUES ('" . $_POST['name'] . "', '" . $hashPassword . "')"; // Put name and password in query

                    if ($conn->query($sql) === TRUE) // Test if query is successful
	     	        {
	    		    	header("Location: login.php");
                    }
			    }
				else
				{
					$passwordError = "Password doesnt fit the <b>requrements</b>, must be " . $passwordMinLength . " to " . $passwordMaxLength . " characters <b>Long</b>";
				}
	        }
	        else // If username contains special chars
    	    {
	        	$usernameError = "Username contains special characters, try with " . clear_string($_POST['name']); // Throw username error
	        }
	    }
    }
    else
	{
		$usernameError = "Username doesnt fit the <b>requrements</b>, must be " . $usernameMinLength . " to " . $usernameMaxLength . " characters <b>Long</b>";
	}
}

$conn->close(); // Closing the SQL connection if no user is logged in
?>