<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 
class MY_Form_validation extends CI_Form_validation {
 
	protected $CI;
 
	function __construct()
	{
		parent::__construct();
 
		$this->CI =& get_instance();
	}
}

/**
 * Fraction
 *
 * @access  public
 * @param   string  $str
 * @return  bool
 */
public function fraction($str)
{
	$this->CI->form_validation->set_message('fraction', 'The %s field must be a valid fraction.');
 
	return ( ! preg_match("/^(\d++(?! */))? *-? *(?:(\d+) */ *(\d+))?.*$/", $str)) ? FALSE : TRUE;
}

$this->form_validation->set_rules('screen_size', 'Screen Size', 'fraction');

/**
 * PCI compliance password
 *
 * @access  public
 * @param   $str
 * @return  bool
 */
public function pci_password($str)
{
	$special = '!@#$%*-_=+.';
 
	$this->CI->form_validation->set_message('pci_password', 'For PCI compliance, %s must be between 6 and 99 characters in length, must not contain two consecutively repeating characters, contain at least one upper-case letter, at least one lower-case letter, at least one number, and at least one special character ('.$special.')');
 
	return (preg_match('/^(?=^.{6,99}$)(?=.*[0-9])(?=.*[A-Z])(?=.*[a-z])(?=.*['.$special.'])(?!.*?(.)\1{1,})^.*$/', $str)) ? TRUE : FALSE;
}

$this->form_validation->set_rules('password', 'Password', 'pci_password');

/**
 * Required if another field has a value (related fields) or if a field has a certain value
 *
 * @access  public
 * @param   string  $str
 * @param   string  $field
 * @return  bool
 */
public function required_if($str, $field)
{
	list($fld, $val) = explode(',', $field, 2);
 
	$this->CI->form_validation->set_message('required_if', 'The %s field is required.');
 
	// $fld is filled out
	if (isset($_POST[$fld]))
	{
		// Must have specific value
		if ($val)
		{
			// Not the specific value we are looking for
			if ($_POST[$fld] == $val AND ! $str)
			{
				return FALSE;
			}
		}
 
		return TRUE;
	}
 
	return FALSE;
}

$this->form_validation->set_rules('bar', 'Bar', 'required_if[foo]'); // required if field 'foo' has a value
$this->form_validation->set_rules('foobar', 'Foo Bar', 'required_if[foo,bar]'); // required if field 'foo' has a value of 'bar'

/**
 * Unique
 *
 * @access	public
 * @param	string
 * @param	field
 * @return	bool
 */
public function unique($str, $field)
{
	list($table, $column) = explode(',', $field, 2);
 
	$this->CI->form_validation->set_message('unique', 'The %s that you requested is already in use.');
 
	$query = $this->CI->db->query("SELECT COUNT(*) AS dupe FROM {$this->CI->db->dbprefix($table)} WHERE {$column} = '{$str}'");
	$row = $query->row();
 
	return ($row->dupe > 0) ? FALSE : TRUE;
}

$this->form_validation->set_rules('email', 'Email', 'unique[DBTABLE,DBFIELD]');	// DBTABLE is the database table and DBFIELD is the database field to validation against

/**
 * Unique except. Check if a specific value is in use except when the value is attached to a specific row ID
 *
 * @param	string
 * @param	field
 * @return	bool
 */
public function unique_exclude($str, $field)
{
	list($table, $column, $fld, $id) = explode(',', $field, 4);
 
	$this->CI->form_validation->set_message('unique_exclude', 'The %s that you requested is already in use.');
 
	$query = $this->CI->db->query("SELECT COUNT(*) AS dupe FROM {$this->CI->db->dbprefix($table)} WHERE {$column} = '$str' AND {$fld} <> {$id}");
	$row = $query->row();
 
	return ($row->dupe > 0) ? FALSE : TRUE;
}

$this->form_validation->set_rules('email', 'Email', 'unique[DBTABLE,DBFIELD,IDFIELD,ID]');	// DBTABLE is the database table, DBFIELD is the database field, IDFIELD is the primary key for the table, and ID is the unique ID for the user