<?php
/**
 * Base class for admin screens.
 *
 * @package TurtleReport
 */

namespace TurtleReport\Admin;

use TurtleReport\Support\AdminLinks;

defined( 'ABSPATH' ) || exit;

/**
 * An admin screen registered under the TurtleReport menu.
 */
abstract class AdminPage {

	/** Menu slug; subclasses override it. */
	const SLUG = '';

	/**
	 * Hook suffix WordPress returned when the page was added.
	 *
	 * @var string
	 */
	private $hook = '';

	/**
	 * Menu label.
	 *
	 * @return string
	 */
	abstract public function menu_title();

	/**
	 * Label in the top bar. Defaults to the menu label.
	 *
	 * @return string
	 */
	public function nav_title() {
		return $this->menu_title();
	}

	/**
	 * Capability needed to open the screen.
	 *
	 * @return string
	 */
	abstract public function capability();

	/**
	 * Outputs the screen.
	 *
	 * @return void
	 */
	abstract public function render();

	/**
	 * Enqueues assets for the screen. Override when needed.
	 *
	 * @return void
	 */
	public function enqueue() {}

	/**
	 * URL of the screen.
	 *
	 * @param array $args Extra query arguments.
	 * @return string
	 */
	public static function url( array $args = array() ) {
		return AdminLinks::url( static::SLUG, $args );
	}

	/**
	 * Remembers the hook suffix and hooks asset loading to this screen only.
	 *
	 * @param string $hook Hook suffix.
	 * @return void
	 */
	public function set_hook( $hook ) {
		$this->hook = (string) $hook;
		if ( '' !== $this->hook ) {
			add_action( 'load-' . $this->hook, array( $this, 'on_load' ) );
		}
	}

	/**
	 * Runs when the screen loads, before output.
	 *
	 * @return void
	 */
	public function on_load() {
		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue' ) );
		add_action( 'admin_notices', array( Notices::class, 'render' ) );
	}

	/**
	 * Registers the shared admin stylesheet.
	 *
	 * @return void
	 */
	protected function enqueue_admin_style() {
		wp_enqueue_style( 'turtlereport-admin', TURTLEREPORT_URL . 'assets/css/admin.css', array( 'turtlereport-shell' ), self::asset_version( 'assets/css/admin.css' ) );
	}

	/**
	 * Version string for a plugin asset. Adds the file's modified time, so an
	 * updated file is fetched again even when browser or page caches kept the
	 * old one under the same plugin version.
	 *
	 * @param string $relative Path relative to the plugin folder.
	 * @return string
	 */
	public static function asset_version( $relative ) {
		$time = @filemtime( TURTLEREPORT_DIR . $relative ); // phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged -- A missing file just falls back to the plugin version.
		return $time ? TURTLEREPORT_VERSION . '.' . $time : TURTLEREPORT_VERSION;
	}
}