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<?php

/**
 * Create URL Title
 *
 * Takes a "title" string as input and creates a
 * human-friendly URL string with either a dash
 * or an underscore as the word separator.
 *
 * @access	public
 * @param	string	the string
 * @param	string	the separator: dash, or underscore
 * @return	string
 */
if ( ! function_exists('url_title'))
{
	function url_title($str, $separator = 'dash', $lowercase = FALSE)
	{
		if ($separator == 'dash') {
			$search		= '_';
			$replace	= '-';
		} else {
			$search		= '-';
			$replace	= '_';
		}

		$trans = array(
				'&\#\d+?;'		=> '',
				'&\S+?;'		=> '',
				'\s+'			=> $replace,
				'[^a-z0-9\-\._]'	=> '',
				$replace.'+'		=> $replace,
				$replace.'$'		=> $replace,
				'^'.$replace		=> $replace,
				'\.+$'			=> ''
			);

		$str = strip_tags($str);

		foreach ($trans as $key => $val) {
			$str = preg_replace("#".$key."#i", $val, $str);
		}

		if ($lowercase === TRUE) {
			$str = strtolower($str);
		}

		return trim(stripslashes($str));
	}
}