wikimedia/mediawiki-extensions-Wikibase

<?php

namespace Wikibase\DataModel\Snak;

use InvalidArgumentException;
use Wikibase\DataModel\Entity\EntityId;
use Wikibase\DataModel\Entity\NumericPropertyId;
use Wikibase\DataModel\Entity\Property;
use Wikibase\DataModel\Entity\PropertyId;

/**
 * Base class for snaks.
 * See https://www.mediawiki.org/wiki/Wikibase/DataModel#Snaks
 *
 * @since 0.1
 *
 * @license GPL-2.0-or-later
 * @author Jeroen De Dauw < jeroendedauw@gmail.com >
 */
abstract class SnakObject implements Snak {

    /**
     * @since 0.1
     *
     * @var PropertyId
     */
    protected $propertyId;

    /**
     * Support for passing in an EntityId instance that is not a PropertyId instance has
     * been deprecated since 0.5.
     *
     * @since 0.1
     *
     * @param PropertyId|EntityId|int $propertyId
     *
     * @throws InvalidArgumentException
     */
    public function __construct( $propertyId ) {
        if ( is_int( $propertyId ) ) {
            $propertyId = NumericPropertyId::newFromNumber( $propertyId );
        }

        if ( !( $propertyId instanceof EntityId ) ) {
            throw new InvalidArgumentException( '$propertyId must be an instance of EntityId' );
        }

        if ( $propertyId->getEntityType() !== Property::ENTITY_TYPE ) {
            throw new InvalidArgumentException( '$propertyId must have an entityType of ' . Property::ENTITY_TYPE );
        }

        if ( !( $propertyId instanceof PropertyId ) ) {
            $propertyId = new NumericPropertyId( $propertyId->getSerialization() );
        }

        $this->propertyId = $propertyId;
    }

    /**
     * @see PropertyIdProvider::getPropertyId
     *
     * @since 0.1
     *
     * @return PropertyId
     */
    public function getPropertyId() {
        return $this->propertyId;
    }

    /**
     * @return string
     */
    public function getHash(): string {
        return sha1( $this->getSerializationForHash() );
    }

    /**
     * The serialization to use for hashing, for compatibility reasons this is
     * equivalent to the old (pre 7.4) PHP serialization.
     *
     * @return string
     */
    public function getSerializationForHash(): string {
        $data = $this->serialize();
        return 'C:' . strlen( static::class ) . ':"' . static::class .
            '":' . strlen( $data ) . ':{' . $data . '}';
    }

    /**
     *
     * @since 0.3
     *
     * @param mixed $target
     *
     * @return bool
     */
    public function equals( $target ) {
        if ( $this === $target ) {
            return true;
        }

        return is_object( $target )
            && get_called_class() === get_class( $target )
            && $this->getHash() === $target->getHash();
    }

    /**
     * @see Serializable::serialize
     *
     * @since 7.0 serialization format changed in an incompatible way
     *
     * @return string
     */
    public function serialize() {
        return $this->propertyId->getSerialization();
    }

    /**
     * @see Serializable::unserialize
     *
     * @since 0.1
     *
     * @param string $serialized
     */
    public function unserialize( $serialized ) {
        try {
            $this->propertyId = new NumericPropertyId( $serialized );
        } catch ( InvalidArgumentException $ex ) {
            // Backwards compatibility with the previous serialization format
            $this->propertyId = NumericPropertyId::newFromNumber( unserialize( $serialized ) );
        }
    }

    public function __serialize(): array {
        return [ $this->propertyId->getSerialization() ];
    }

    public function __unserialize( array $serialized ): void {
        $this->propertyId = new NumericPropertyId( $serialized[0] );
    }

}