Multi level referral system

[davidolson]

db table    username------>id->username->cash->points->referrer

db table    referral_levels------>id->level->earnings->signupBonusCash->signupBonusPoints->status

username    referrer
--------    --------
admin
kelly88     admin   // UPDATE USERNAME ADMIN WITH referral level 1 POINTS/CASH //
jacob       kelly88 // UPDATE USERNAME ADMIN WITH referral level 2 POINTS/CASH AND USERNAME kelly88 WITH referral level 1 POINTS/CASH //
david16     jacob   // UPDATE USERNAME ADMIN WITH referral level 3 POINTS/CASH AND USERNAME kelly88 WITH referral level 2 POINTS/CASH AND USERNAME jacob WITH referral level 1 POINTS/CASH //

Is this possible. If yes - HOW?

 

Current test registration code with referral level 1

<?php
if(!empty($_GET['ref'])){
	
	$referrerUsername = filter_input(INPUT_GET, 'ref', FILTER_SANITIZE_STRING);
	
	if(usernameExist($referrerUsername, $db) === TRUE){
		$_SESSION['ref'] = $referrerUsername;
	}
	
}

// define variables with the value for each field
// the value from POST,GET if this exist, or an empty value
$errors = array();
$username = isset($_POST['username']) ? filter_input(INPUT_POST, 'username', FILTER_SANITIZE_STRING) : '';
$referrer = !empty($_SESSION['ref']) ? $_SESSION['ref'] : (isset($_POST['referrer']) ? filter_input(INPUT_POST, 'referrer', FILTER_SANITIZE_STRING) : '');

if(!empty($_POST['submit'])){
	
	if(empty($username)){
       	 $errors[] = $lang['error']['a_019'];
    }
	else if(validUsernameLenght($username) === FALSE){
        $errors[] = $lang['error']['a_020'];
   	}
	else if(validUsernameChars($username) === FALSE){
        $errors[] = $lang['error']['a_021'];
    }
	else if(usernameExist($username, $db) === TRUE){
       	$errors[] = $lang['error']['a_022'];
    }
	
	if(!empty($referrer)){
		
		if(usernameExist($referrer, $db) === FALSE){
			$errors[] = $lang['error']['a_037'];
		}
		else if($username == $referrer){
			$errors[] = $lang['error']['a_038'];
		}
			
	}
	
}

if(!empty($_POST['submit']) and empty($errors)){
	/*
	$queryOne = 'INSERT INTO users(username, referrer) VALUES (:username, :referrer)';
	$insertOne = $db->prepare($queryOne);
	$insertOne->bindParam(':username', $username, PDO::PARAM_STR);
	$insertOne->bindParam(':referrer', $referrer, PDO::PARAM_STR);
	$successOne = $insertOne->execute();
	*/
	if($referrer){
		
		$query = 'SELECT signupBonusCash AS sbc, signupBonusPoints AS sbp FROM referral_levels WHERE level = 1 AND status = "enabled"';
		$select = $db->query($query);
		$row = $select->fetch(PDO::FETCH_ASSOC);
		
		$queryTwo = 'UPDATE users SET points = points + :points, cash = cash + :cash WHERE username = :referrer';
   	 	$selectTwo = $db->prepare($queryTwo);
		$selectTwo->bindParam(':cash', $row['sbc'], PDO::PARAM_STR);
		$selectTwo->bindParam(':points', $row['sbp'], PDO::PARAM_STR);
		$selectTwo->bindParam(':referrer', $referrer, PDO::PARAM_STR);
		$selectTwo->execute();
		
	}
	
}

if(!empty($errors)){ 
	foreach($errors as $error){
		print $error.'<br>'; 
	}
}	

print '
<form method="POST">
<table style="width:100%">
	<tr>
    	<td style="width:30%;font-weight:bold">Username</td>
    	<td style="width:70%"><input type="text" name="username" maxlength="255" style="width:200px" value="'.cleanOutput($username).'"></td>
	</tr>';
	
	if(!empty($_SESSION['ref'])){
		
		print '
	<tr>
    	<td style="font-weight:bold">'.$lang['global']['a_047'].'</td>
    	<td><input type="text" name="referrer" readonly="readonly" maxlength="255" style="width:200px" value="'.cleanOutput($referrer).'"></td>
  	</tr>';
	
	}else{
		
		print '
	<tr>
    	<td style="font-weight:bold">'.$lang['global']['a_047'].'</td>
    	<td><input type="text" name="referrer" maxlength="255" style="width:200px" value="'.cleanOutput($referrer).'"></td>
  	</tr>';
	
	}
	
	print '
	<tr>
    	<td colspan="2" style="text-align:center"><input type="submit" name="submit" value="Submit"></td>
  	</tr>
</table>
</form>'; 

?>