class ConditionExpressionContainer

abstract class ConditionExpressionContainer extends ExpressionContainerBase implements ConditionExpressionContainerInterface, ContainerFactoryPluginInterface {
    
    /**
     * List of conditions that are evaluated.
     *
     * @var \Drupal\rules\Engine\ConditionExpressionInterface[]
     */
    protected $conditions = [];
    
    /**
     * Constructs a new class instance.
     *
     * @param array $configuration
     *   A configuration array containing information about the plugin instance.
     * @param string $plugin_id
     *   The plugin_id for the plugin instance.
     * @param array $plugin_definition
     *   The plugin implementation definition.
     * @param \Drupal\rules\Engine\ExpressionManagerInterface $expression_manager
     *   The rules expression plugin manager.
     * @param \Drupal\Core\Logger\LoggerChannelInterface $logger
     *   The Rules debug logger channel.
     */
    public function __construct(array $configuration, $plugin_id, array $plugin_definition, ExpressionManagerInterface $expression_manager, LoggerChannelInterface $logger) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->expressionManager = $expression_manager;
        $this->rulesDebugLogger = $logger;
        $configuration += [
            'conditions' => [],
        ];
        foreach ($configuration['conditions'] as $condition_config) {
            $condition = $this->expressionManager
                ->createInstance($condition_config['id'], $condition_config);
            $this->conditions[] = $condition;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function addExpressionObject(ExpressionInterface $expression) {
        if (!$expression instanceof ConditionExpressionInterface) {
            throw new InvalidExpressionException('Only condition expressions can be added to a condition container.');
        }
        $uuid = $expression->getUuid();
        if ($this->getExpression($uuid)) {
            throw new InvalidExpressionException("A condition with UUID {$uuid} already exists in the container.");
        }
        $this->conditions[] = $expression;
        return $this;
    }
    
    /**
     * {@inheritdoc}
     */
    public function addCondition($condition_id, ContextConfig $config = NULL) {
        return $this->addExpressionObject($this->expressionManager
            ->createCondition($condition_id)
            ->setConfiguration($config ? $config->toArray() : []));
    }
    
    /**
     * {@inheritdoc}
     */
    public function executeWithState(ExecutionStateInterface $rules_state) {
        $result = $this->evaluate($rules_state);
        return $this->isNegated() ? !$result : $result;
    }
    
    /**
     * Returns the final result after executing the conditions.
     */
    public abstract function evaluate(ExecutionStateInterface $rules_state);
    
    /**
     * {@inheritdoc}
     */
    public function negate($negate = TRUE) {
        $this->configuration['negate'] = $negate;
        return $this;
    }
    
    /**
     * {@inheritdoc}
     */
    public function isNegated() {
        return !empty($this->configuration['negate']);
    }
    
    /**
     * {@inheritdoc}
     */
    public function getConfiguration() {
        $configuration = parent::getConfiguration();
        // We need to update the configuration in case conditions have been added or
        // changed.
        $configuration['conditions'] = [];
        // Use the iterator, which sorts the conditions by weight.
        foreach ($this as $condition) {
            $configuration['conditions'][] = $condition->getConfiguration();
        }
        return $configuration;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getIterator() : \Traversable {
        $iterator = new \ArrayIterator($this->conditions);
        $iterator->uasort([
            ExpressionContainerBase::class,
            'sortByWeightProperty',
        ]);
        return $iterator;
    }
    
    /**
     * PHP magic __clone function.
     */
    public function __clone() {
        // Implement a deep clone.
        foreach ($this->conditions as &$condition) {
            $condition = clone $condition;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function getExpression($uuid) {
        foreach ($this->conditions as $condition) {
            if ($condition->getUuid() === $uuid) {
                return $condition;
            }
            if ($condition instanceof ExpressionContainerInterface) {
                $nested_condition = $condition->getExpression($uuid);
                if ($nested_condition) {
                    return $nested_condition;
                }
            }
        }
        return FALSE;
    }
    
    /**
     * {@inheritdoc}
     */
    public function deleteExpression($uuid) {
        foreach ($this->conditions as $index => $condition) {
            if ($condition->getUuid() === $uuid) {
                unset($this->conditions[$index]);
                return TRUE;
            }
            if ($condition instanceof ExpressionContainerInterface && $condition->deleteExpression($uuid)) {
                return TRUE;
            }
        }
        return FALSE;
    }

}