<?php
defined( 'ABSPATH' ) || exit;
/**
 * Plugin bootstrap.
 *
 * Loads the shell, loads whichever feature modules are present in this build,
 * then lets everything register its hooks through one loader.
 *
 * Module files are required only if they exist, so the shell boots cleanly
 * while the other build lanes are still landing their classes. Modules attach
 * themselves on the 'advisorppc_loaded' action, which fires after every file
 * has been included and before the loader runs.
 *
 * @package AdvisorPPC
 */

/**
 * Class AdvisorPPC_Plugin.
 */
class AdvisorPPC_Plugin {

	/**
	 * Singleton.
	 *
	 * @var AdvisorPPC_Plugin|null
	 */
	protected static $instance = null;

	/**
	 * Hook loader.
	 *
	 * @var AdvisorPPC_Loader
	 */
	protected $loader;

	/**
	 * Connect flow.
	 *
	 * @var AdvisorPPC_Connect
	 */
	protected $connect;

	/**
	 * Admin screens. Null on the front end.
	 *
	 * @var AdvisorPPC_Admin|null
	 */
	protected $admin = null;

	/**
	 * Whether run() has already been called.
	 *
	 * @var bool
	 */
	protected $booted = false;

	/**
	 * Module class files that other lanes own, loaded when present.
	 *
	 * @var string[]
	 */
	protected $module_files = array(
		// Module 1: tags, consent, click IDs. Module 4: shield.
		'includes/class-advisorppc-consent.php',
		'includes/class-advisorppc-clickids.php',
		'includes/class-advisorppc-tags.php',
		'includes/class-advisorppc-shield.php',
		// Modules 2 and 3: server-side conversions and WooCommerce.
		'includes/class-advisorppc-signer.php',
		'includes/class-advisorppc-queue.php',
		'includes/class-advisorppc-events.php',
		'includes/class-advisorppc-woo.php',
		// Module 2b: form leads.
		'includes/class-advisorppc-forms.php',
		'includes/class-advisorppc-tracktor.php',
		// Auto setup: read-only detection of existing tags.
		'includes/class-advisorppc-detect.php',
		// Site verification meta tags and YouTube video tracking.
		'includes/class-advisorppc-verification.php',
		'includes/class-advisorppc-video.php',
	);

	/**
	 * The singleton.
	 *
	 * @return AdvisorPPC_Plugin
	 */
	public static function instance() {
		if ( null === self::$instance ) {
			self::$instance = new self();
		}

		return self::$instance;
	}

	/**
	 * Build the object graph. Registers no hooks.
	 */
	protected function __construct() {
		$this->loader  = new AdvisorPPC_Loader();
		$this->connect = new AdvisorPPC_Connect();
	}

	/**
	 * Boot.
	 *
	 * @return void
	 */
	public function run() {
		if ( $this->booted ) {
			return;
		}

		$this->booted = true;

		$this->load_modules();
		$this->load_admin();

		// No load_plugin_textdomain(): WordPress 4.6+ loads translations for
		// the `advisorppc` slug from translate.wordpress.org on its own.

		$this->connect->register( $this->loader );

		if ( $this->admin ) {
			$this->admin->register( $this->loader );
		}

		/**
		 * Fires once every AdvisorPPC class file has been loaded and before
		 * any hook is attached. Feature modules register here.
		 *
		 * @param AdvisorPPC_Loader $loader Hook loader.
		 * @param AdvisorPPC_Plugin $plugin Plugin instance.
		 */
		do_action( 'advisorppc_loaded', $this->loader, $this );

		$this->loader->run();
	}

	/**
	 * Include whichever feature module files this build ships.
	 *
	 * @return void
	 */
	protected function load_modules() {
		foreach ( $this->module_files as $relative ) {
			$path = ADVISORPPC_PLUGIN_DIR . $relative;

			if ( file_exists( $path ) ) {
				require_once $path;
			}
		}
	}

	/**
	 * Include the admin screens, admin requests only.
	 *
	 * @return void
	 */
	protected function load_admin() {
		if ( ! is_admin() ) {
			return;
		}

		require_once ADVISORPPC_PLUGIN_DIR . 'admin/class-advisorppc-settings.php';
		require_once ADVISORPPC_PLUGIN_DIR . 'admin/class-advisorppc-admin.php';

		$this->admin = new AdvisorPPC_Admin( $this->connect );
	}

	/**
	 * The hook loader, so modules can register outside the action.
	 *
	 * @return AdvisorPPC_Loader
	 */
	public function loader() {
		return $this->loader;
	}

	/**
	 * The connect flow object.
	 *
	 * @return AdvisorPPC_Connect
	 */
	public function connect() {
		return $this->connect;
	}

	/**
	 * Plugin version.
	 *
	 * @return string
	 */
	public function version() {
		return ADVISORPPC_VERSION;
	}
}