/**
* Merge the headers of two translations.
*
* @param Translations $from
* @param Translations $to
* @param int $options
*/
public static function mergeHeaders(Translations $from, Translations $to, $options = self::DEFAULTS)
{
if ($options & self::HEADERS_REMOVE) {
foreach (array_keys($to->getHeaders()) as $name) {
if ($from->getHeader($name) === null) {
$to->deleteHeader($name);
}
}
}
foreach ($from->getHeaders() as $name => $value) {
$current = $to->getHeader($name);
if (empty($current)) {
if ($options & self::HEADERS_ADD) {
$to->setHeader($name, $value);
}
continue;
}
if (empty($value)) {
continue;
}
switch ($name) {
case Translations::HEADER_LANGUAGE:
case Translations::HEADER_PLURAL:
if ($options & self::LANGUAGE_OVERRIDE) {
$to->setHeader($name, $value);
}
break;
case Translations::HEADER_DOMAIN:
if ($options & self::DOMAIN_OVERRIDE) {
$to->setHeader($name, $value);
}
break;
default:
if ($options & self::HEADERS_OVERRIDE) {
$to->setHeader($name, $value);
}
}
}
}