$terms = $_GET['title'];
if (mb_check_encoding($terms, $default_encoding) && !mb_check_encoding($terms, 'UTF-8')) {
$terms = mb_convert_encoding($terms, 'UTF-8', $default_encoding);
}
}
}
if (!isset($terms) || empty($terms)) {
if (!isset($_GET['author'])) {
exit;
}
$author = $_GET['author'];
if (mb_check_encoding($author, $default_encoding) && !mb_check_encoding($author, 'UTF-8')) {
$author = mb_convert_encoding($author, 'UTF-8', $default_encoding);
}
if (!empty($author)) {
$books = $db->searchBooksByAuthor($author);
showBooks($opds, $books, $page, "Search results: " . $author);
exit;
}
} else {
$books = $db->searchBooksByTitle($terms);
showBooks($opds, $books, $page, "Search results: " . $terms);
exit;
}
} elseif ($count > 1) {
$lvl_parent = $levels[$count - 2];
if ($lvl_parent === 'genres') {
$books = $db->getBooksByGenre($lvl_last);
showBooks($opds, $books, $page, "Genre: " . $lvl_last);
}
if ($lvl_parent === 'authors') {
