src/Entity/Citation.php
<?php
namespace Drupal\stanford_publication\Entity;
use Drupal\Core\Entity\ContentEntityInterface;
use Drupal\Core\Field\BaseFieldDefinition;
use Drupal\Core\Entity\ContentEntityBase;
use Drupal\Core\Entity\EntityChangedTrait;
use Drupal\Core\Entity\EntityTypeInterface;
use Drupal\Core\Link;
use Drupal\Core\TypedData\TranslatableInterface;
use Drupal\Core\Url;
use Drupal\field\Entity\FieldStorageConfig;
use Seboettg\CiteProc\CiteProc;
/**
* Defines the Citation entity.
*
* @ingroup stanford_publication
*
* @ContentEntityType(
* id = "citation",
* label = @Translation("Citation"),
* bundle_label = @Translation("Citation type"),
* handlers = {
* "view_builder" = "Drupal\stanford_publication\CitationViewBuilder",
* "access" = "Drupal\stanford_publication\CitationAccessControlHandler",
* "form" = {
* "default" = "Drupal\Core\Entity\ContentEntityForm",
* "delete" = "Drupal\Core\Entity\ContentEntityDeleteForm",
* "edit" = "Drupal\Core\Entity\ContentEntityForm"
* },
* "views_data" = "Drupal\views\EntityViewsData",
* },
* base_table = "citation",
* data_table = "citation_field_data",
* translatable = TRUE,
* permission_granularity = "bundle",
* admin_permission = "administer citation entities",
* entity_keys = {
* "id" = "id",
* "bundle" = "type",
* "label" = "title",
* "uuid" = "uuid",
* "langcode" = "langcode",
* "published" = "status",
* },
* bundle_entity_type = "citation_type",
* field_ui_base_route = "entity.citation_type.edit_form"
* )
*/
class Citation extends ContentEntityBase implements CitationInterface {
use EntityChangedTrait;
/**
* {@inheritdoc}
*/
public function setLabel($name): CitationInterface {
$this->set('title', $name);
return $this;
}
/**
* {@inheritdoc}
*/
public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
$fields = parent::baseFieldDefinitions($entity_type);
$fields['title'] = BaseFieldDefinition::create('string')
->setLabel(t('Title'))
->setDescription(t('The title of the Citation.'))
->setSettings([
'max_length' => 255,
'text_processing' => 0,
])
->setDefaultValue('')
->setDisplayOptions('view', [
'label' => 'above',
'type' => 'string',
'weight' => -4,
])
->setDisplayOptions('form', [
'type' => 'string_textfield',
'weight' => -4,
])
->setDisplayConfigurable('form', TRUE)
->setDisplayConfigurable('view', TRUE);
$fields['created'] = BaseFieldDefinition::create('created')
->setLabel(t('Created'))
->setDescription(t('The time that the entity was created.'));
$fields['changed'] = BaseFieldDefinition::create('changed')
->setLabel(t('Changed'))
->setDescription(t('The time that the entity was last edited.'));
$fields['parent_id'] = BaseFieldDefinition::create('string')
->setLabel(t('Parent ID'))
->setDescription(t('The ID of the parent entity of which this entity is referenced.'))
->setSetting('is_ascii', TRUE);
$fields['parent_type'] = BaseFieldDefinition::create('string')
->setLabel(t('Parent type'))
->setDescription(t('The entity parent type to which this entity is referenced.'))
->setSetting('is_ascii', TRUE)
->setSetting('max_length', EntityTypeInterface::ID_MAX_LENGTH);
$fields['parent_field_name'] = BaseFieldDefinition::create('string')
->setLabel(t('Parent field name'))
->setDescription(t('The entity parent field name to which this entity is referenced.'))
->setSetting('is_ascii', TRUE)
->setSetting('max_length', FieldStorageConfig::NAME_MAX_LENGTH);
return $fields;
}
/**
* {@inheritDoc}
*/
public function getParentEntity() {
if (!isset($this->get('parent_type')->value) || !isset($this->get('parent_id')->value)) {
return NULL;
}
$parent = $this->entityTypeManager()
->getStorage($this->get('parent_type')->value)
->load($this->get('parent_id')->value);
// Return current translation of parent entity, if it exists.
if (
$parent != NULL &&
($parent instanceof TranslatableInterface) &&
$parent->hasTranslation($this->language()->getId())
) {
return $parent->getTranslation($this->language()->getId());
}
return $parent;
}
/**
* {@inheritdoc}
*/
public function setParentEntity(ContentEntityInterface $parent, $parent_field_name) {
$this->set('parent_type', $parent->getEntityTypeId());
$this->set('parent_id', $parent->id());
$this->set('parent_field_name', $parent_field_name);
return $this;
}
/**
* {@inheritDoc}
*/
public function getBibliography($style = self::APA): string {
$data = [
'id' => $this->id(),
'title' => $this->label(),
// Custom variables that wrap the title with a link tag.
'link-beginning' => $this->getLinkBeginning(),
'link-ending' => $this->getLinkBeginning() ? '</a>' : NULL,
'DOI' => $this->getDoi(),
'URL' => $this->getUrl(),
'author' => $this->getAuthor(),
'edition' => (int) $this->getEdition(),
'issue' => $this->getIssue(),
'issued' => $this->getDate(),
'genre' => $this->getGenre(),
'page' => $this->getPage(),
'publisher' => $this->getPublisher(),
'publisher-place' => $this->getPublisherPlace(),
'subtitle' => $this->getSubtitle(),
'type' => $this->getType(),
'volume' => (int) $this->getVolume(),
];
if ($data['type'] == 'article-journal') {
$data['collection-title'] = $data['publisher'];
}
// Convert the arrays into objects.
$data = json_decode(json_encode([array_filter($data)]));
$local_csl = __DIR__ . '/Styles/' . $style . '.xml';
if (!file_exists($local_csl)) {
return '';
}
// Load the style CSL file.
$style = file_get_contents($local_csl);
$citeProc = new CiteProc($style);
return htmlspecialchars_decode($citeProc->render($data));
}
/**
* If the citation can be linked to a url, get the first part of the <a> tag.
*
* @return string|null
* First half of the <a> tag.
*
* @throws \Drupal\Core\Entity\EntityMalformedException
*/
protected function getLinkBeginning() {
if ($link = $this->getLink()) {
// This will pull out the `<a href....>` part of the link.
preg_match('/<a.*?>/', (string) $link->toString(), $matches);
return $matches[0] ?? NULL;
}
}
/**
* Get the label of the entity wrapped in a link tag to the parent or url.
*
* @return \Drupal\Core\Link|null
* Label or linked label string.
*
* @throws \Drupal\Core\Entity\EntityMalformedException
*/
protected function getLink() {
$url = NULL;
// Link to the parent node.
if ($parent_entity = $this->getParentEntity()) {
$url = $parent_entity->toUrl();
}
// The user entered url.
if ($url_string = $this->getUrl()) {
$url = $this->getUrlFromString($url_string) ?? $url;
}
if ($url) {
return Link::fromTextAndUrl('[replace]', $url);
}
}
/**
* Get a url object from the provided url/string.
*
* @param string $string
* User entered string.
*
* @return \Drupal\Core\Url|null
* Url object if successful.
*/
protected function getUrlFromString($string): ?Url {
try {
return Url::fromUserInput($string);
}
catch (\Exception $e) {
try {
return Url::fromUri($string);
}
catch (\Exception $e) {
// Nothing to do, just fall back to returning null.
}
}
return NULL;
}
/**
* Fallback function to get the entity field's string value.
*
* @param string $name
* Function name.
* @param mixed $args
* Args.
*
* @return string
* Entity field value as a string.
*/
public function __call($name, $args) {
// Remove the `get` from the beginning.
$data_name = preg_replace('/^get/', '', $name);
// Convert UpperCamelCase to snake_case. This allows us to dynamically
// fetch field names just by using the method names. Later versions it would
// be preferred to have a UI that allows the user to choose which field
// maps to which variable in the CSL.
preg_match_all('!([A-Z][A-Z0-9]*(?=$|[A-Z][a-z0-9])|[A-Za-z][a-z0-9]+)!', $data_name, $matches);
$ret = $matches[0];
foreach ($ret as &$match) {
$match = $match == strtoupper($match) ? strtolower($match) : lcfirst($match);
}
$data_name = implode('_', $ret);
if ($field = $this->getFieldName($data_name)) {
return $this->get($field)->getString();
}
}
/**
* Get the list of authors from the entity field.
*
* @return array|null
* Keyed array of author data.
*/
protected function getAuthor() {
// Authors are rendered using `names` render element in CSL. It expects
// the name array to be keyed with `given`, `family` etc keys. Luckily the
// name module does this for us.
// @link https://docs.citationstyles.org/en/1.0.1/specification.html#names
if ($field = $this->getFieldName('author')) {
return $this->get($field)->getValue();
}
}
/**
* Get the type of citation being used.
*
* @return string
* Citation type.
*/
protected function getType(): string {
return $this->entityTypeManager()
->getStorage('citation_type')
->load($this->bundle())
->type();
}
/**
* Get the structured date array from the entity.
*
* The structure of a date field is an associate array with the year, month,
* day in that order. We have to construct the array in a way that doesn't
* return the year and day without the month.
*
* @link https://docs.citationstyles.org/en/1.0.1/specification.html#date
*
* @return array|null
* Keyed array of date parts.
*/
protected function getDate() {
$year = (int) $this->getYear();
$month = (int) $this->getMonth();
$day = (int) $this->getDay();
if ($year) {
$date_parts = [$year, $month];
// The 2nd value has to be the month. If the user populates the year,
// month and day, then we'll structure it correctly. Otherwise we leave
// the day off and if the month is also empty, it'll be stripped in the
// array filter below.
if ($month && $day) {
$date_parts = [$year, $month, $day];
}
return [
'date-parts' => [array_filter($date_parts)],
];
}
}
/**
* Get the name of the field that is associated to the the attribute value.
*
* @param string $attribute
* Citation attribute key.
*
* @return string|null
* Field name if a field exists.
*/
protected function getFieldName($attribute) {
$field_name = "su_$attribute";
// Later versions this will be a field mapping on the entity type config.
if ($field_name && $this->hasField($field_name)) {
return $field_name;
}
}
}