case 'url':
case 'url_inline':
$inline = ($mode == 'url') ? ')' : '';
$scheme = ($mode == 'url') ? '[a-z\d+\-.]' : '[a-z\d+]'; // avoid automatic parsing of "word" in "last word.http://..."
// generated with regex generation file in the develop folder
return "[a-z]$scheme*:/{2}(?:(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})+|[0-9.]+|\[[a-z0-9.]+:[a-z0-9.]+:[a-z0-9.:]+\])(?::\d*)?(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
break;

case 'www_url':
case 'www_url_inline':
$inline = ($mode == 'www_url') ? ')' : '';
return "www\.(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})+(?::\d*)?(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
break;

case 'relative_url':
case 'relative_url_inline':
$inline = ($mode == 'relative_url') ? ')' : '';
return "(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
break;

case 'url':
case 'url_inline':
$inline = ($mode == 'url') ? ')' : '';
$scheme = ($mode == 'url') ? '[a-z\d+\-.]' : '[a-z\d+]'; // avoid automatic parsing of "word" in "last word.http://..."
// generated with regex generation file in the develop folder
//return "[a-z]$scheme*:/{2}(?:(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})+|[0-9.]+|\[[a-z0-9.]+:[a-z0-9.]+:[a-z0-9.:]+\])(?::\d*)?(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
// by http://joomir.com ahmad balavipour 
return "[a-z][a-z\d+\-.]*:/{2}(?:(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@|]+|%[\dA-F]{2})+|[0-9.]+|\[[a-z0-9.]+:[a-z0-9.]+:[a-z0-9.:]+\])(?::\d*)?(?:/(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@/?|]+|%[\dA-F]{2})*)?";
break;

case 'www_url':
case 'www_url_inline':
$inline = ($mode == 'www_url') ? ')' : '';
//return "www\.(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})+(?::\d*)?(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
return "www\.(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@|]+|%[\dA-F]{2})+(?::\d*)?(?:/(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@/?|]+|%[\dA-F]{2})*)?";
break;

case 'relative_url':
case 'relative_url_inline':
$inline = ($mode == 'relative_url') ? ')' : '';
//return "(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
return "(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@|]+|%[\dA-F]{2})*(?:/(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[\x80-\xFFa-z0-9\-._~!$&'()*+,;=:@/?|]+|%[\dA-F]{2})*)?";
break;