<?php
/**
 * Admin menu.
 *
 * @package HostKhata
 */

namespace HostKhata\Admin;

defined( 'ABSPATH' ) || exit;

use HostKhata\Core\Capabilities;
use HostKhata\Core\Hookable;

/**
 * Registers the single top-level HostKhata menu. All navigation happens inside the React app.
 *
 * @since 0.1.0
 */
final class Menu implements Hookable {

	/**
	 * Menu and page slug.
	 */
	const SLUG = 'hostkhata';

	/**
	 * Renders the app container.
	 *
	 * @var AppShell
	 */
	private $shell;

	/**
	 * Constructor.
	 *
	 * @param AppShell $shell App shell.
	 */
	public function __construct( AppShell $shell ) {
		$this->shell = $shell;
	}

	/**
	 * {@inheritdoc}
	 */
	public function register(): void {
		add_action( 'admin_menu', array( $this, 'add_menu' ) );
		add_filter( 'admin_body_class', array( $this, 'add_body_class' ) );
	}

	/**
	 * Capability required to open the app.
	 *
	 * @since 0.1.0
	 *
	 * @return string
	 */
	public static function capability(): string {
		/**
		 * Filters the capability required to open the HostKhata admin app.
		 *
		 * @since 0.1.0
		 *
		 * @param string $capability Capability name.
		 */
		return (string) apply_filters( 'hostkhata_menu_capability', Capabilities::ACCESS_APP );
	}

	/**
	 * Hook suffix of the app page.
	 *
	 * @since 0.1.0
	 *
	 * @return string
	 */
	public static function screen_id(): string {
		return 'toplevel_page_' . self::SLUG;
	}

	/**
	 * Tells whether a hook suffix belongs to the app page.
	 *
	 * @since 0.1.0
	 *
	 * @param string $hook_suffix Admin page hook suffix.
	 * @return bool
	 */
	public static function is_app_screen( string $hook_suffix ): bool {
		return self::screen_id() === $hook_suffix;
	}

	/**
	 * Adds the menu entry.
	 *
	 * @since 0.1.0
	 *
	 * @return void
	 */
	public function add_menu(): void {
		add_menu_page(
			__( 'HostKhata', 'hostkhata' ),
			__( 'HostKhata', 'hostkhata' ),
			self::capability(),
			self::SLUG,
			array( $this->shell, 'render' ),
			'dashicons-money-alt',
			26
		);
	}

	/**
	 * Adds a body class on the app screen so full-width styles can apply.
	 *
	 * @since 0.1.0
	 *
	 * @param string $classes Space separated body classes.
	 * @return string
	 */
	public function add_body_class( $classes ): string {
		$screen = function_exists( 'get_current_screen' ) ? get_current_screen() : null;

		if ( $screen && self::screen_id() === $screen->id ) {
			$classes .= ' hostkhata-screen';
		}

		return (string) $classes;
	}
}