Task::parseTags

private function parseTags(array $fields): array
{
	$tags = [];
	$searchFields = ['TITLE', 'DESCRIPTION'];

	foreach ($searchFields as $code)
	{
		if (!array_key_exists($code, $fields))
		{
			continue;
		}
		if (preg_match_all(self::REGEX_TAG, ' '.$fields[$code], $matches))
		{
			$tags[] = $matches[1];
		}
	}

	$tags = array_merge([], ...$tags);
	if (
		array_key_exists('TAGS', $fields)
		&& !empty($fields['TAGS'])
	)
	{
		$tags = array_merge($fields['TAGS'], $tags);
	}

	return array_unique($tags);
}