<?php

namespace Barn2\PTS_Lib;

/**
 * Abstract class which represents a single scheduled task using WordPress CRON.
 *
 * The task is automatically unscheduled on plugin deactivation.
 *
 * @package   Barn2\barn2-lib
 * @author    Barn2 Plugins <support@barn2.com>
 * @license   GPL-3.0
 * @copyright Barn2 Media Ltd
 * @version   1.0
 */
abstract class Scheduled_Task implements Schedulable {

	private $plugin_file;

	public function __construct( $plugin_file ) {
		$this->plugin_file = $plugin_file;
	}

	public function schedule() {
		// Attach the action to run when the cron event is fired.
		add_action( $this->get_cron_hook(), [ $this, 'run' ] );

		// Schedule the cron event if not already scheduled.
		if ( ! wp_next_scheduled( $this->get_cron_hook() ) ) {
			wp_schedule_event( time(), $this->get_interval(), $this->get_cron_hook() );
		}

		// Un-schedule the event on plugin deactivation.
		register_deactivation_hook( $this->plugin_file, [ $this, 'unschedule' ] );
	}

	abstract protected function get_cron_hook();

	abstract protected function get_interval();

	public function unschedule() {
		$timestamp = wp_next_scheduled( $this->get_cron_hook() );

		if ( $timestamp ) {
			wp_unschedule_event( $timestamp, $this->get_cron_hook() );
		}
	}

	abstract public function run();

}