wikimedia/mediawiki-core

<?php

namespace MediaWiki\HookContainer;

use InvalidArgumentException;
use LogicException;
use OutOfBoundsException;

/**
 * @internal
 */
class FauxHookHandlerArray implements \ArrayAccess, \IteratorAggregate {

    private HookContainer $hookContainer;

    private string $name;

    private ?array $handlers = null;

    /**
     * @param HookContainer $hookContainer
     * @param string $name
     */
    public function __construct( HookContainer $hookContainer, string $name ) {
        $this->hookContainer = $hookContainer;
        $this->name = $name;
    }

    /**
     * @inheritDoc
     */
    #[\ReturnTypeWillChange]
    public function offsetExists( $offset ) {
        return $this->getHandler( $offset ) !== null;
    }

    /**
     * @inheritDoc
     */
    #[\ReturnTypeWillChange]
    public function offsetGet( $offset ) {
        $handler = $this->getHandler( $offset );

        if ( !$handler ) {
            throw new OutOfBoundsException( "No such index in the handler list: $offset" );
        }

        return $handler;
    }

    /**
     * @inheritDoc
     */
    #[\ReturnTypeWillChange]
    public function offsetSet( $offset, $value ) {
        if ( $offset !== null ) {
            throw new InvalidArgumentException( '$offset must be null, this array is append only' );
        }

        $this->hookContainer->register( $this->name, $value );
        $this->handlers = null;
    }

    /**
     * @inheritDoc
     * @return never
     */
    #[\ReturnTypeWillChange]
    public function offsetUnset( $offset ) {
        throw new LogicException( 'unset is not supported for hook handler arrays' );
    }

    private function getHandler( $offset ) {
        if ( $this->handlers === null ) {
            // NOTE: getHandlerCallbacks() only exists to support this.
            //       It should be deleted when we no longer need it here.
            $this->handlers = $this->hookContainer->getHandlerCallbacks( $this->name );
        }

        return $this->handlers[$offset] ?? null;
    }

    #[\ReturnTypeWillChange]
    public function getIterator() {
        if ( $this->handlers === null ) {
            // NOTE: getHandlerCallbacks() only exists to support this.
            //       It should be deleted when we no longer need it here.
            $this->handlers = $this->hookContainer->getHandlerCallbacks( $this->name );
        }

        return new \ArrayIterator( $this->handlers );
    }
}