<?php
/**
 * Main plugin loader (composition root).
 *
 * @package BlockSieve
 */

namespace BlockSieve;

use BlockSieve\Container\Container;
use BlockSieve\Providers\AdminServiceProvider;
use BlockSieve\Providers\AssetServiceProvider;
use BlockSieve\Providers\CoreServiceProvider;
use BlockSieve\Providers\RenderServiceProvider;
use BlockSieve\Providers\RestServiceProvider;
use BlockSieve\Providers\ServiceProviderInterface;

/**
 * Boots the plugin through the service container and registered providers.
 *
 * Each provider binds its services into the container, then boots them (queuing
 * WordPress hooks through the HookLoader), and finally every queued hook is
 * committed in one pass. Translations are loaded by WordPress itself: plugins
 * hosted on WordPress.org receive language packs automatically, so no explicit
 * load_plugin_textdomain() call is needed.
 */
final class Plugin {

	/**
	 * Singleton instance.
	 *
	 * @var self|null
	 */
	private static ?self $instance = null;

	/**
	 * The service container.
	 *
	 * @var Container
	 */
	private Container $container;

	/**
	 * Registered service providers, in registration order.
	 *
	 * @var ServiceProviderInterface[]
	 */
	private array $providers = array();

	/**
	 * Returns the shared plugin instance.
	 *
	 * @return self
	 */
	public static function instance(): self {
		return self::$instance ??= new self();
	}

	/**
	 * Constructor — private, use ::instance().
	 */
	private function __construct() {
		$this->container = new Container();
		$this->providers = array(
			new CoreServiceProvider(),
			new AssetServiceProvider(),
			new RenderServiceProvider(),
			new RestServiceProvider(),
			new AdminServiceProvider(),
		);
	}

	/**
	 * Boots the plugin on the plugins_loaded hook.
	 *
	 * @return void
	 */
	public function boot(): void {
		// 1. Bind services into the container.
		foreach ( $this->providers as $provider ) {
			$provider->register( $this->container );
		}

		// 2. Resolve services and wire hooks.
		foreach ( $this->providers as $provider ) {
			$provider->boot( $this->container );
		}

		// 3. Commit all queued WordPress hooks.
		$this->container->get( HookLoader::class )->register();
	}

	/**
	 * Returns the service container.
	 *
	 * @return Container
	 */
	public function container(): Container {
		return $this->container;
	}
}