protected function loadRelations($reload = false) {
if ($this->loaded['relations'] && !$reload) return;
if (!$this->id) {
return;
}
Z_Core::debug("Loading relations for item $this->id");
$this->loadPrimaryData(false, true);
$itemURI = Zotero_URI::getItemURI($this);
$relations = Zotero_Relations::getByURIs($this->libraryID, $itemURI);
$relations = array_map(function ($rel) {
return [$rel->predicate, $rel->object];
}, $relations);
// Related items are bidirectional, so include any with this item as the object
$reverseRelations = Zotero_Relations::getByURIs(
$this->libraryID, false, Zotero_Relations::$relatedItemPredicate, $itemURI
);
foreach ($reverseRelations as $rel) {
$r = [$rel->predicate, $rel->subject];
// Only add if not already added in other direction
if (!in_array($r, $relations)) {
$relations[] = $r;
}
}
// Also include any owl:sameAs relations with this item as the object
// (as sent by client via classic sync)
$reverseRelations = Zotero_Relations::getByURIs(
$this->libraryID, false, Zotero_Relations::$linkedObjectPredicate, $itemURI
);
foreach ($reverseRelations as $rel) {
$relations[] = [$rel->predicate, $rel->subject];
}
// TEMP: Get old-style related items
//
// Add related items
$sql = "SELECT `key` FROM itemRelated IR "
. "JOIN items I ON (IR.linkedItemID=I.itemID) "
. "WHERE IR.itemID=?";
$relatedItemKeys = Zotero_DB::columnQuery($sql, $this->id, Zotero_Shards::getByLibraryID($this->libraryID));
if ($relatedItemKeys) {
$prefix = Zotero_URI::getLibraryURI($this->libraryID) . "/items/";
$predicate = Zotero_Relations::$relatedItemPredicate;
foreach ($relatedItemKeys as $key) {
$relations[] = [$predicate, $prefix . $key];
}
}
// Reverse as well
$sql = "SELECT `key` FROM itemRelated IR JOIN items I USING (itemID) WHERE IR.linkedItemID=?";
$reverseRelatedItemKeys = Zotero_DB::columnQuery(
$sql, $this->id, Zotero_Shards::getByLibraryID($this->libraryID)
);
if ($reverseRelatedItemKeys) {
$prefix = Zotero_URI::getLibraryURI($this->libraryID) . "/items/";
$predicate = Zotero_Relations::$relatedItemPredicate;
foreach ($reverseRelatedItemKeys as $key) {
$relations[] = [$predicate, $prefix . $key];
}
}
$this->relations = $relations;
$this->loaded['relations'] = true;
$this->clearChanged('relations');
}
/**
* Updates the collection's relations. No separate save of the collection is required.
*
* @param object $newRelations Object with predicates as keys and URIs as values
* @param int $userID User making the change
*/
public function setRelations($newRelations, $userID)
{
if (!$this->_id) {
throw new Exception('collectionID not set');
}
// An empty array is allowed by updateFromJSON()
if (is_array($newRelations) && empty($newRelations)) {
$newRelations = new stdClass();
}
Zotero_DB::beginTransaction();
// Get arrays from objects
$oldRelations = get_object_vars($this->getRelations());
$newRelations = get_object_vars($newRelations);
$toAdd = array_diff($newRelations, $oldRelations);
$toRemove = array_diff($oldRelations, $newRelations);
if (!$toAdd && !$toRemove) {
Zotero_DB::commit();
return false;
}
$subject = Zotero_URI::getCollectionURI($this);
foreach ($toAdd as $predicate => $object) {
Zotero_Relations::add($this->libraryID, $subject, $predicate, $object);
}
foreach ($toRemove as $predicate => $object) {
$relations = Zotero_Relations::getByURIs($this->libraryID, $subject, $predicate, $object);
foreach ($relations as $relation) {
Zotero_Relations::delete($this->libraryID, $relation->key);
}
}
$this->updateVersion($userID);
Zotero_DB::commit();
return true;
}
