/**
* Add a reference to the cache, checking for prior duplicates.
* @param integer $key = a unique key
* @param WCReference $reference
* @return integer = number of citations from last use of this reference.
*/
public function addUniqueReference( $key, WCReference $reference ) {
$referenceKey = array( $key );
$hash = $reference->getHash();
if ( empty( $hash ) ) {
# If empty hash, search all prior hashed references.
foreach( $this->hashTable as &$hashArray ) {
foreach( $hashArray as &$testKey ) {
$testReference = $this->references[ $testKey ];
# If $reference can be considered a short form of prior reference:
if ( $reference->shortFormMatches( $testReference ) ) {
$lastKey = end( $testReference ->keys );
$testReference->keys += $referenceKey;
# Forget this reference:
$this->references[ $key ] = $testReference;
return $key - $lastKey;
}
# If prior reference can be considered a short form of $reference:
elseif ( $testReference->shortFormMatches( $reference ) ) {
$lastKey = end( $testReference ->keys );
$reference->keys = $testReference->keys + $referenceKey;
# Forget the earlier reference.
unset( $this->referenceList [ $testKey ] );
$this->referenceList[ $key ] = $reference;
$this->references[ $testKey ] = $reference;
$this->references[ $key ] = $reference;
$testKey = $key;
return $key - $lastKey;
}
}
}
}
# Handle hash table collisions.
elseif ( isset( $this->hashTable[ $hash ] ) ) {
# Search collision entries.
foreach( $this->hashTable[ $hash ] as &$testKey ) {
$testReference = $this->references[ $testKey ];
# If $reference can be considered a short form of prior reference:
if ( $reference->shortFormMatches( $testReference ) ) {
$lastKey = end( $testReference ->keys );
$testReference->keys += $referenceKey;
# Forget this reference:
$this->references[ $key ] = $testReference;
return $key - $lastKey;
}
# if prior reference can be considered a short form of $reference:
elseif ( $testReference->shortFormMatches( $reference ) ) {
$lastKey = end( $testReference ->keys );
$reference->keys = $testReference->keys + $referenceKey;
# Forget the earlier reference.
unset( $this->referenceList [ $testKey ] );
$this->referenceList[ $key ] = $reference;
$this->references[ $testKey ] = $reference;
$this->references[ $key ] = $reference;
$testKey = $key;
return $key - $lastKey;
}
}
# If no collision yet, search prior empty hashes.
foreach( $this->hashTable[ '' ] as $id => &$testKey ) {
$testReference = $this->references[ $testKey ];
if ( $testReference->shortFormMatches( $reference ) ) {
$lastKey = end( $testReference ->keys );
$reference->keys = $testReference->keys + $referenceKey;
# Forget the earlier reference.
unset( $this->referenceList [ $testKey ] );
$this->referenceList [ $key ] = $reference;
$this->references[ $testKey ] = $reference;
$this->references[ $key ] = $reference;
# Correct hash table
unset( $this->hashTable[ '' ][ $id ] );
$this->hashTable[ $hash ][] = $key;
return $key - $lastKey;
}
}
}
# If no hash table match:
$reference->keys = $referenceKey;
$this->referenceList[ $key ] = $reference;
$this->references[ $key ] = $reference;
$this->hashTable[ $hash ][] = $key;
return 0;
}
