<?php 
class AppModel extends Model
{
	function getUniqueUrl($string, $field)
	{
		// Build URL
		
		$currentUrl = $this->_getStringAsURL($string);
		
		// Look for same URL, if so try until we find a unique one
		
		$conditions = array($this->name . '.' . $field => 'LIKE ' . $currentUrl . '%');
		
		$result = $this->findAll($conditions, $this->name . '.*', null);
		
		if ($result !== false && count($result) > 0)
		{
			$sameUrls = array();
			
			foreach($result as $record)
			{
				$sameUrls[] = $record[$this->name][$field];
			}
		}
	
		if (isset($sameUrls) && count($sameUrls) > 0)
		{
			$currentBegginingUrl = $currentUrl;
	
			$currentIndex = 1;
	
			while($currentIndex > 0)
			{
				if (!in_array($currentBegginingUrl . '_' . $currentIndex, $sameUrls))
				{
					$currentUrl = $currentBegginingUrl . '_' . $currentIndex;
	
					$currentIndex = -1;
				}
	
				$currentIndex++;
			}
		}
		
		return $currentUrl;
	}
	
	function _getStringAsURL($string)
	{
		// Define the maximum number of characters allowed as part of the URL
		
		$currentMaximumURLLength = 100;
		
		$string = strtolower($string);
		
		// Any non valid characters will be treated as _, also remove duplicate _
		
		$string = preg_replace('/[^a-z0-9_]/i', '_', $string);
		$string = preg_replace('/_[_]*/i', '_', $string);
		
		// Cut at a specified length
		
		if (strlen($string) > $currentMaximumURLLength)
		{
			$string = substr($string, 0, $currentMaximumURLLength);
		}
		
		// Remove beggining and ending signs
		
		$string = preg_replace('/_$/i', '', $string);
		$string = preg_replace('/^_/i', '', $string);
		
		return $string;
	}
}
?>