ThemePicker::filterUnavailableThemes

private function filterUnavailableThemes($config)
{
	if (!is_array($config) || !isset($config["subThemes"]) || !is_array($config["subThemes"]))
	{
		return [];
	}

	$now = time();
	$delta = 24 * 3600 * 10;
	foreach ($config["subThemes"] as $themeId => $theme)
	{
		if (isset($theme["releaseDate"]))
		{
			$releaseDate = strtotime($theme["releaseDate"]);
			if ($releaseDate !== false && ($releaseDate - $delta) > $now)
			{
				unset($config["subThemes"][$themeId]);
				continue;
			}
		}

		if (isset($theme["zones"]) && is_array($theme["zones"]) && !in_array($this->getZoneId(), $theme["zones"]))
		{
			unset($config["subThemes"][$themeId]);
			continue;
		}
	}

	return $config;
}