felixarntz/theme-boilerplate

<?php
/**
 * Super_Awesome_Theme_Theme class
 *
 * @package Super_Awesome_Theme
 * @license GPL-2.0-or-later
 * @link    https://super-awesome-author.org/themes/super-awesome-theme/
 */

/**
 * Main class of the theme.
 *
 * @since 1.0.0
 */
final class Super_Awesome_Theme_Theme {

    /**
     * Registered theme components.
     *
     * @since 1.0.0
     * @var array
     */
    private $components = array();

    /**
     * Map of components and their dependants.
     *
     * @since 1.0.0
     * @var array
     */
    private $dependants_map = array();

    /**
     * Registers a theme component.
     *
     * @since 1.0.0
     *
     * @param Super_Awesome_Theme_Theme_Component $component Component that implements a dependency.
     * @return Super_Awesome_Theme_Theme Theme instance for chaining.
     */
    public function register_component( Super_Awesome_Theme_Theme_Component $component ) {
        $dependency_classes = $component->get_dependency_classes();
        foreach ( $dependency_classes as $class_name ) {
            if ( ! isset( $this->dependants_map[ $class_name ] ) ) {
                $this->dependants_map[ $class_name ] = array();
            }

            $this->dependants_map[ $class_name ][] = $component;
        }

        $shorthand_identifier                      = $this->make_shorthand_identifier( get_class( $component ) );
        $this->components[ $shorthand_identifier ] = $component;

        return $this;
    }

    /**
     * Gets a registered theme component.
     *
     * @since 1.0.0
     *
     * @param string $shorthand_identifier Short-hand identifier of the component, which is the class name
     *                                     without the theme prefix all lowercased.
     * @return Super_Awesome_Theme_Theme_Component|null Theme component, or null if not registered.
     */
    public function get_component( $shorthand_identifier ) {
        if ( ! isset( $this->components[ $shorthand_identifier ] ) ) {
            return null;
        }

        return $this->components[ $shorthand_identifier ];
    }

    /**
     * Resolves all dependencies for the registered theme components.
     *
     * @since 1.0.0
     *
     * @return Super_Awesome_Theme_Theme Theme instance for chaining.
     */
    public function resolve_dependencies() {
        foreach ( $this->components as $component ) {
            foreach ( $this->dependants_map as $class_name => $dependants ) {
                if ( $component instanceof $class_name ) {
                    foreach ( $dependants as $dependant ) {
                        $dependant->provide_dependency( $component );
                    }
                }
            }
        }

        return $this;
    }

    /**
     * Initializes all registered theme components.
     *
     * @since 1.0.0
     *
     * @return Super_Awesome_Theme_Theme Theme instance for chaining.
     */
    public function initialize() {
        foreach ( $this->components as $component ) {
            $component->initialize();
        }

        return $this;
    }

    /**
     * Returns the short-hand identifier for a full class name.
     *
     * @since 1.0.0
     *
     * @param string $class_name Full class name.
     * @return string Short-hand identifier.
     */
    private function make_shorthand_identifier( $class_name ) {
        return strtolower( str_replace( 'Super_Awesome_Theme_', '', $class_name ) );
    }
}