/**
*
* @param string $userAgent
* @return string
*/
function lookForMatchingUserAgent($userAgent)
{
$tolerance = 0;
if (WURFL_Handlers_Utils::checkIfStartsWith($userAgent, "Apple")) {
$tolerance = WURFL_Handlers_Utils::ordinalIndexOf($userAgent, " ", 3);
} else {
$tolerance = WURFL_Handlers_Utils::firstSemiColonOrLength($userAgent);
}
return WURFL_Handlers_Utils::risMatch(array_keys($this->userAgentsWithDeviceID), $userAgent, $tolerance);
}