/**
* Dedup: Return (unique) ISBNs in ISBN-13 format without dashes
*
* @return string[]
*/
public function getISBNs()
{
$arr = [];
$fields = $this->getFields('020');
foreach ($fields as $field) {
$isbn = $this->getSubfield($field, 'a');
$isbn = MetadataUtils::normalizeISBN($isbn);
if ($isbn) {
$arr[] = $isbn;
}
}
return array_values(array_unique($arr));
}
/**
* Get an array of all fields relevant to allfields search
*
* @return string[]
*/
protected function getAllFields()
{
$subfieldFilter = ['650' => ['0' => 1, '2' => 1, '6' => 1, '8' => 1], '773' => ['0' => 1, '6' => 1, '7' => 1, '8' => 1, 'w' => 1], '856' => ['0' => 1, '6' => 1, '8' => 1, 'q' => 1], '979' => ['0' => 1, 'a' => 1, 'f' => 1]];
$allFields = [];
// Include ISBNs, also normalized if possible
foreach ($this->getFields('020') as $field) {
$isbns = $this->getSubfieldsArray($field, ['a' => 1, 'z' => 1]);
foreach ($isbns as $isbn) {
$allFields[] = $isbn;
$isbn = MetadataUtils::normalizeISBN($isbn);
if ($isbn) {
$allFields[] = $isbn;
}
}
}
foreach ($this->fields as $tag => $fields) {
if ($tag >= 100 && $tag < 841 && $tag != 336 && $tag != 337 || $tag == 856 || $tag == 880 || $tag == 979) {
foreach ($fields as $field) {
$subfields = $this->getAllSubfields($field, isset($subfieldFilter[$tag]) ? $subfieldFilter[$tag] : ['0' => 1, '6' => 1, '8' => 1]);
if ($subfields) {
$allFields = array_merge($allFields, $subfields);
}
}
}
}
$allFields = array_map(function ($str) {
return MetadataUtils::stripLeadingPunctuation(MetadataUtils::stripTrailingPunctuation($str));
}, $allFields);
return array_values(array_unique($allFields));
}
