<?php

abstract class AbstactEntityFactory
{
    /**
     * @param mixed[] $state
     */
    abstract public function createEntity(array $state): EntityInterface;

    /**
     * @param mixed[] $state
     */
    abstract public function createEntityCollection(array $states): EntityCollectionInterface;
}

class FooEntityFactory extends AbstactEntityFactory
{
    /**
     * {@inheritdoc}
     */
    public function createEntity(array $state): EntityInterface
    {
        return Foo::fromState($state);
    }

    /**
     * {@inheritdoc}
     */
    public function createEntityCollection(array $states): EntityCollectionInterface
    {
        return new FooCollection(array_map('Foo::fromState', $states));
    }
}

class BarEntityFactory extends AbstactEntityFactory
{
    /**
     * {@inheritdoc}
     */
    public function createEntity(array $state): EntityInterface
    {
        return Bar::fromState($state);
    }

    /**
     * {@inheritdoc}
     */
    public function createEntityCollection(array $states): EntityCollectionInterface
    {
        return new BarCollection(array_map('Bar::fromState', $states));
    }
}