<?php
/**
 * @package AccessMate
 * @license GPL-2.0-or-later
 */
defined( 'ABSPATH' ) || exit;

class AccessMate_Scheduler {

    /**
     * Register the custom cron intervals early — must run before wp_get_schedules()
     * is first called (which happens during wp_next_scheduled() later in the same request).
     * Called on plugins_loaded priority 1 from accessmate.php.
     */
    public static function register_schedules(): void {
        add_filter( 'cron_schedules', [ self::class, 'add_schedules' ] );
    }

    /**
     * Scheduled scans are Pro-only. A Free/unlicensed site gets no cron event
     * at all — not even the old homepage-only fallback — and any event left
     * over from a lapsed licence is cleared out.
     */
    public static function register(): void {
        add_action( 'accessmate_scheduled_scan', [ self::class, 'run' ] );

        if ( ! AccessMate_Licensing::is_premium() ) {
            $timestamp = wp_next_scheduled( 'accessmate_scheduled_scan' );
            if ( $timestamp ) {
                wp_unschedule_event( $timestamp, 'accessmate_scheduled_scan' );
            }
            return;
        }

        if ( ! wp_next_scheduled( 'accessmate_scheduled_scan' ) ) {
            $frequency = get_option( 'accessmate_settings', [] )['scan_schedule'] ?? 'weekly';
            wp_schedule_event( self::first_run_timestamp( $frequency ), $frequency, 'accessmate_scheduled_scan' );
        }
    }

    /**
     * Reschedule the cron event when the scan schedule setting changes.
     * Call this after saving new settings. No-ops (beyond clearing the old
     * event) on a Free/unlicensed site — see register().
     */
    public static function reschedule( string $new_frequency ): void {
        $timestamp = wp_next_scheduled( 'accessmate_scheduled_scan' );
        if ( $timestamp ) {
            wp_unschedule_event( $timestamp, 'accessmate_scheduled_scan' );
        }
        if ( AccessMate_Licensing::is_premium() ) {
            wp_schedule_event( self::first_run_timestamp( $new_frequency ), $new_frequency, 'accessmate_scheduled_scan' );
        }
    }

    /**
     * First-run time for a newly (re)scheduled event — one full interval from
     * now, not immediately. wp_schedule_event()'s first argument is the first
     * run time, not a "start no earlier than" bound — passing time() makes
     * WP-Cron treat the event as already due on the very next page load, which
     * is what silently kicked off a full site scan right after Pro activation.
     */
    private static function first_run_timestamp( string $frequency ): int {
        $schedules = wp_get_schedules();
        $interval  = $schedules[ $frequency ]['interval'] ?? WEEK_IN_SECONDS;
        return time() + $interval;
    }

    public static function add_schedules( array $schedules ): array {
        if ( ! isset( $schedules['weekly'] ) ) {
            $schedules['weekly'] = [
                'interval' => WEEK_IN_SECONDS,
                'display'  => __( 'Once Weekly', 'accessmate' ),
            ];
        }
        if ( ! isset( $schedules['monthly'] ) ) {
            $schedules['monthly'] = [
                'interval' => 30 * DAY_IN_SECONDS,
                'display'  => __( 'Once Monthly', 'accessmate' ),
            ];
        }
        return $schedules;
    }

    /**
     * Runs on the `accessmate_scheduled_scan` cron event. Pro-only, and it
     * no longer scans anything itself — WP-Cron has no DOM/JS runtime, so it
     * can't drive the axe-core pipeline the rest of the app uses. It only
     * marks the scan "due"; an authorized admin's dashboard session then
     * claims and runs it through the same axe-core pipeline as Bulk/
     * Individual scans — see AccessMate_Pro::mark_scheduled_scan_due() and
     * useScheduledScanRunner.ts. register() never schedules this event for a
     * Free/unlicensed site, so the class_exists() guard here is just a
     * safety net for a stray event left over from before a licence lapsed.
     */
    public static function run(): void {
        if ( class_exists( 'AccessMate_Pro' ) ) {
            AccessMate_Pro::mark_scheduled_scan_due();
        }
    }
}