Some example which needs refactoring

refactor1.php

<?php
/**
 * Table post
 *
 * id,
 * title,
 * body
 * author_id
 */
class PostGateway
{
    public function getPosts()
    {
      return $this->db->query("SELECT * FROM posts");
    }
}

class AuthorGateway
{
    public function getAuthors($post_ids)
    {
      // assuming the query is correct
      return $this->db->query("SELECT * FROM authors WHERE id IN (:post_ids)", $post_ids);
    }
}

class AuthorFactory
{
    public function newInstance($data)
    {
        $author = new Author($data);
        return $author;
    }
}

class PostFactory
{
    public function newInstance($data, Author $author)
    {
        $post = new Post($data);
        $post->author = $author;
        return $post;
    }
}

class PostService
{
    protected $post_gateway;
    
    protected $author_gateway;
    
    public function __construct(
        PostGateway $post_gateway, 
        AuthorGateway $author_gateway, 
        PostFactory $post_factory, 
        AuthorFactory $author_factory
    )
    {
        $this->post_gateway = $post_gateway;
        $this->post_factory = $post_factory;
        $this->author_gateway = $author_gateway;
        $this->author_factory = $author_factory;
    }
  
    public function getPosts()
    {
        $posts = array();
        $posts_result = $this->post_gateway->getPosts();
        $post_ids = array();
        // iterate and get post_ids;
        foreach ($posts as $post) {
            $post_ids[] = $post['id'];
        }        
        $authors_result = $this->author_gateway->getAuthors();
        // let us iterate and make a key of author_id
        foreach ($posts_result as $post) {
            $author = $this->author_factory->newInstance($authors_result[$post['author_id']]);
            $posts[] = $this->post_factory->newInstance($post, $author);
        }
        return $posts;
    }
}

class Post
{
    public $id;
    public $title;
    public $body;
    public $author
}

class Author
{
    public $id;
    public $username;
    public $displayname;
}
 
class Something
{
    public function indexAction()
    {
        $post_service = new PostService(
            new PostGateway(),
            new AuthorGateway(),
            new PostFactory(),
            new AuthorFactory(),
        );
        $this->view->posts = $post_service->getPosts();
    }
}

something.php

<?php
/**
 * Table post
 * 
 * id,
 * title,
 * body
 * author_id
 */
class SomeModel
{
  public function getPosts()
  {
    return $this->db->query("SELECT * FROM POSTS");
  }
}

class Something
{
    public function indexAction()
    {
      $somemodel = new SomeModel(
        // pass deps 
      );
      $posts = $somemodel->getPosts();
    }
}