WordPress class to generate post types

WPSSCtp.php

<?php
/**
 * Class WPSSCpt
 * Generate custom post types
 */

class WPSSCpt {
    
    /**
     * Class instance
     *
     * @var object|null $instance
     */
    protected static ?object $instance = null;
    
    /**
     * Define custom post type unique key
     *
     * @var string $cpt_key
     */
    public static string $cpt_key;
    
    /**
     * Define custom post type name.
     *
     * @var string $cpt_name
     */
    public static string $cpt_name;
    
    /**
     * Define custom post type labels, keep empty to default labels
     *
     * @var array $cpt_labels
     */
    public static array $cpt_labels = [];
    
    /**
     * Define custom post type capabilities, keep empty to custom capabilities
     *
     * @var string
     */
    public static string $cpt_capabilities = '';
    
    /**
     * Set roles with access to post type, administrator always have permission
     *
     * @var array|string[]
     */
    public static array $add_caps_to_role = [];
    
    /**
     * Define custom post type labels, keep empty to default args
     *
     * @var array $cpt_args
     */
    public static array $cpt_args = [];
    
    /**
     * WPSSCpt constructor.
     * Use the following attributes to configure your CPT:
     *
     * @var string $cpt_key          Unique post type key. Eg.: gallery_cpt
     * @var string $cpt_name         The post type name. Eg.: Gallery
     * @var array $cpt_labels        The post type labels. Eg.: $my_class_instance::$cpt_labels = ['featured_image' => 'Gallery Cover']
     * @var string $cpt_capabilities The post type capabilities type, use to clone capabilities from another post type.
     * @var array $add_caps_to_role  Define roles to manage CPT, by default, administrator always have access. Eg.: $my_class_instance::$add_caps_to_role = ['editor', 'my_role']
     * @var array $cpt_args          The post type args, to define custom args to your cpt, use: $my_class_instance::$cpt_args = ['menu_position' => 6];
     */
    public function __construct() {
        add_action('admin_init', [ $this, 'set_caps_to_role' ]);
        add_action('enter_title_here', [ $this, 'custom_post_type_input_title_placeholder' ], 10, 1);
    }
    
    /**
     * Init custom post type
     */
    public static function make_cpt() {
        $instance = self::instance();
        register_post_type(self::$cpt_key, $instance->cpt_args());
    }
    
    /**
     * Get class instance
     *
     * @return object|WPSSCpt|null
     */
    public static function instance() {
        if( is_null(self::$instance) ):
            self::$instance = new self();
        endif;
        return self::$instance;
    }
    
    /**
     * Define custom post type default args
     *
     * @return array
     */
    private function cpt_args(): array {
        $args = self::$cpt_args;
        $args = [
            'label'               => self::$cpt_name,
            'description'         => (isset($args['description']) ? $args['description'] : ""),
            'labels'              => self::cpt_labels(),
            'supports'            => (isset($args['supports']) ? $args['supports'] : [ 'title', 'editor', 'thumbnail' ]),
            'taxonomies'          => (isset($args['taxonomies']) ? $args['taxonomies'] : []),
            'hierarchical'        => (isset($args['hierarchical']) ? $args['hierarchical'] : false),
            'public'              => (isset($args['public']) ? $args['public'] : true),
            'show_ui'             => (isset($args['show_ui']) ? $args['show_ui'] : true),
            'show_in_menu'        => (isset($args['show_in_menu']) ? $args['show_in_menu'] : true),
            'menu_position'       => (isset($args['menu_position']) ? $args['menu_position'] : 5),
            'menu_icon'           => (isset($args['menu_icon']) ? $args['menu_icon'] : 'dashicons-arrow-right'),
            'show_in_admin_bar'   => (isset($args['show_in_admin_bar']) ? $args['show_in_admin_bar'] : true),
            'show_in_nav_menus'   => (isset($args['show_in_nav_menus']) ? $args['show_in_nav_menus'] : true),
            'can_export'          => (isset($args['can_export']) ? $args['can_export'] : true),
            'has_archive'         => (isset($args['has_archive']) ? $args['has_archive'] : self::cpt_rewrite()['slug']),
            'exclude_from_search' => (isset($args['exclude_from_search']) ? $args['exclude_from_search'] : false),
            'publicly_queryable'  => (isset($args['publicly_queryable']) ? $args['publicly_queryable'] : true),
            'rewrite'             => self::cpt_rewrite(),
            'show_in_rest'        => (isset($args['show_in_rest']) ? $args['show_in_rest'] : true),
            'rest_base'           => (isset($args['rest_base']) ? $args['rest_base'] : self::cpt_rewrite()['slug']),
        ];
        if( self::$cpt_capabilities ):
            $args['capability_type'] = self::$cpt_capabilities;
        else:
            $args['capabilities'] = self::cpt_caps();
        endif;
        
        return $args;
    }
    
    /**
     * Define custom post type labels
     *
     * @return array
     */
    private function cpt_labels(): array {
        $labels        = self::$cpt_labels;
        $cpt_name      = self::$cpt_name;
        $singular_name = (isset($labels['singular_name']) ? $labels['singular_name'] : $cpt_name);
        return [
            'name'                  => $cpt_name,
            'singular_name'         => $cpt_name,
            'menu_name'             => $cpt_name,
            'name_admin_bar'        => $cpt_name,
            'archives'              => $cpt_name,
            'attributes'            => (isset($labels['attributes']) ? $labels['attributes'] : __("Item Attributes", "wpss")),
            'parent_item_colon'     => (isset($labels['parent_item_colon']) ? $labels['parent_item_colon'] : __("Parent Item:", "wpss")),
            'all_items'             => (isset($labels['all_items']) ? $labels['all_items'] : __("All Items", "wpss")),
            'add_new_item'          => (isset($labels['add_new_item']) ? $labels['add_new_item'] : __("Add New $singular_name", "wpss")),
            'add_new'               => (isset($labels['add_new']) ? $labels['add_new'] : __("Add New", "wpss")),
            'new_item'              => (isset($labels['new_item']) ? $labels['new_item'] : __("New $singular_name", "wpss")),
            'edit_item'             => (isset($labels['edit_item']) ? $labels['edit_item'] : __("Edit $singular_name Video", "wpss")),
            'update_item'           => (isset($labels['update_item']) ? $labels['update_item'] : __("Update $singular_name", "wpss")),
            'view_item'             => (isset($labels['view_item']) ? $labels['view_item'] : __("View $singular_name", "wpss")),
            'view_items'            => (isset($labels['view_items']) ? $labels['view_items'] : __("View $cpt_name", "wpss")),
            'search_items'          => (isset($labels['search_items']) ? $labels['search_items'] : __("Search $cpt_name", "wpss")),
            'not_found'             => (isset($labels['not_found']) ? $labels['not_found'] : __("Not found", "wpss")),
            'not_found_in_trash'    => (isset($labels['not_found_in_trash']) ? $labels['not_found_in_trash'] : __("Not found in trash", "wpss")),
            'featured_image'        => (isset($labels['featured_image']) ? $labels['featured_image'] : __("Featured image", "wpss")),
            'set_featured_image'    => (isset($labels['set_featured_image']) ? $labels['set_featured_image'] : __("Set featured image", "wpss")),
            'remove_featured_image' => (isset($labels['remove_featured_image']) ? $labels['remove_featured_image'] : __("Remove featured image", "wpss")),
            'use_featured_image'    => (isset($labels['use_featured_image']) ? $labels['use_featured_image'] : __("Use as featured image", "wpss")),
            'insert_into_item'      => (isset($labels['insert_into_item']) ? $labels['insert_into_item'] : __("Insert into item", "wpss")),
            'uploaded_to_this_item' => (isset($labels['uploaded_to_this_item']) ? $labels['uploaded_to_this_item'] : __("Upload to this item", "wpss")),
            'items_list'            => (isset($labels['items_list']) ? $labels['items_list'] : __("Items list", "wpss")),
            'items_list_navigation' => (isset($labels['items_list_navigation']) ? $labels['items_list_navigation'] : __("Items list navigation", "wpss")),
            'filter_items_list'     => (isset($labels['filter_items_list']) ? $labels['filter_items_list'] : __("Filter items list", "wpss")),
        ];
    }
    
    /**
     * Define custom post type capabilities
     *
     * @return string[]
     */
    private function cpt_caps(): array {
        $cpt_key = self::$cpt_key;
        return [
            'edit_post'              => "edit_{$cpt_key}",
            'read_post'              => "read_{$cpt_key}",
            'delete_post'            => "delete_{$cpt_key}",
            'edit_posts'             => "edit_{$cpt_key}s",
            'edit_others_posts'      => "edit_others_{$cpt_key}s",
            'publish_posts'          => "publish_{$cpt_key}s",
            'delete_posts'           => "delete_{$cpt_key}s",
            'delete_private_posts'   => "delete_private_{$cpt_key}s",
            'delete_published_posts' => "delete_published_{$cpt_key}s",
            'delete_others_posts'    => "delete_others_{$cpt_key}s",
            'read_private_posts'     => "read_private_{$cpt_key}s",
            'edit_published_posts'   => "edit_published_{$cpt_key}s",
            'edit_private_posts'     => "edit_private_{$cpt_key}s",
        ];
    }
    
    /**
     * Set role permissions to custom post type
     */
    public function set_caps_to_role(): void {
        $roles   = self::$add_caps_to_role;
        $roles[] = 'administrator';
        foreach( $roles as $role ):
            foreach( self::cpt_caps() as $cap ):
                get_role($role)->add_cap($cap);
            endforeach;
        endforeach;
    }
    
    /**
     * Define a custom input placeholder to post type edit screen
     *
     * @param $input
     *
     * @return mixed|string
     */
    public function custom_post_type_input_title_placeholder($input): string {
        global $post_type;
        $default_placeholder = sprintf(__("Input the title of %s", "wpss"), self::$cpt_name);
        if( is_admin() && self::$cpt_key === $post_type ):
            if( isset(self::$cpt_args['input_placeholder']) ):
                return self::$cpt_args['input_placeholder'];
            else:
                return $default_placeholder;
            endif;
        endif;
        
        return $input;
    }
    
    /**
     * Define custom post type rewrite params
     *
     * @return array
     */
    private function cpt_rewrite(): array {
        $rewrite = sanitize_title(self::$cpt_name);
        if( isset($this->cpt_args['rewrite']) ):
            $rewrite = sanitize_title(self::$cpt_args['rewrite']);
        endif;
        return [
            'slug'       => $rewrite,
            'with_front' => true,
            'pages'      => true,
            'feeds'      => true,
        ];
    }
    
}

/** Post type sample */
add_action('init', 'new_cpt_gallery');
function new_cpt_gallery() {
    $gallery            = new WPSSCpt();
    $gallery::$cpt_key  = 'my_gallery';
    $gallery::$cpt_name = 'Gallery';
    $gallery::$cpt_labels       = [
        'singular_name'      => 'Album',
        'featured_image'     => 'Album Cover',
        'set_featured_image' => 'Set album cover',
    ];
    $gallery::$cpt_args         = [
        'supports'          => [ 'title', 'editor', 'thumbnail' ],
        'menu_icon'         => 'dashicons-format-image',
        'input_placeholder' => 'Type this album title',
    ];
    $gallery::$add_caps_to_role = [ 'editor' ];
    $gallery::make_cpt();
}