<?php
if ( ! defined( 'ABSPATH' ) ) exit;

class AccessIQ_Scheduler {

    private static $instance = null;
    private $s;

    public static function instance() {
        if ( null === self::$instance ) self::$instance = new self();
        return self::$instance;
    }

    private function __construct() {
        $this->s = AccessIQ_Settings::instance();
        add_action( 'accessiq_scheduled_scan',    [ $this, 'run_scheduled_scan' ] );
        add_action( 'accessiq_cleanup_old_data',  [ $this, 'cleanup_old_data' ] );
        add_action( 'accessiq_settings_saved',    [ $this, 'reschedule' ] );
        add_filter( 'cron_schedules',             [ $this, 'add_schedules' ] );
        $this->maybe_schedule();
    }

    public function add_schedules( $schedules ) {
        $schedules['accessiq_weekly']  = [ 'interval' => WEEK_IN_SECONDS,      'display' => 'Weekly' ];
        $schedules['accessiq_monthly'] = [ 'interval' => MONTH_IN_SECONDS,     'display' => 'Monthly' ];
        return $schedules;
    }

    public function maybe_schedule() {
        if ( ! $this->s->get( 'schedule_enabled' ) ) return;
        if ( ! wp_next_scheduled( 'accessiq_scheduled_scan' ) ) {
            $freq = 'accessiq_' . $this->s->get( 'schedule_freq', 'weekly' );
            wp_schedule_event( time(), $freq, 'accessiq_scheduled_scan' );
        }
        if ( ! wp_next_scheduled( 'accessiq_cleanup_old_data' ) ) {
            wp_schedule_event( time(), 'daily', 'accessiq_cleanup_old_data' );
        }
    }

    public function reschedule() {
        wp_clear_scheduled_hook( 'accessiq_scheduled_scan' );
        wp_clear_scheduled_hook( 'accessiq_cleanup_old_data' );
        $this->maybe_schedule();
    }

    /**
     * Run scheduled scan: trigger server-side scans for up to 10 published pages.
     */
    public function run_scheduled_scan() {
        $pages = get_posts( array(
            'post_type'      => array( 'page', 'post' ),
            'posts_per_page' => 10,
            'post_status'    => 'publish',
        ) );

        $nonce = wp_create_nonce( 'accessiq_nonce' );
        $count = 0;

        foreach ( $pages as $page ) {
            $url = get_permalink( $page->ID );
            if ( ! $url ) {
                continue;
            }
            // Fire-and-forget — 5s timeout, non-blocking.
            wp_remote_post(
                admin_url( 'admin-ajax.php' ),
                array(
                    'timeout'  => 5,
                    'blocking' => false,
                    'body'     => array(
                        'action' => 'accessiq_scheduled_scan_page',
                        'nonce'  => $nonce,
                        'url'    => $url,
                    ),
                )
            );
            ++$count;
        }

        // Send notification email.
        $email = $this->s->get( 'notify_email', get_option( 'admin_email' ) );
        if ( $email ) {
            wp_mail(
                $email,
                __( 'AccessIQ — Scheduled Scan Triggered', 'accessiq' ),
                /* translators: 1: number of pages, 2: site URL */
                sprintf( __( 'A scheduled accessibility scan has been triggered for %1$d pages on %2$s.', 'accessiq' ), $count, home_url() )
            );
        }
    }

    /**
     * Delete analytics rows older than the configured retention period.
     * Runs daily via cron.
     */
    public function cleanup_old_data() {
        global $wpdb;

        $days = absint( get_option( 'accessiq_analytics_data_retention', 90 ) );
        if ( $days < 7 ) {
            $days = 7; // safety minimum
        }

        $cutoff = gmdate( 'Y-m-d H:i:s', strtotime( '-' . $days . ' days', current_time( 'timestamp' ) ) );

        // phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
        $wpdb->query( $wpdb->prepare(
            'DELETE FROM `' . esc_sql( $wpdb->prefix . 'accessiq_clicks' ) . '` WHERE created_at < %s',
            $cutoff
        ) );
        $wpdb->query( $wpdb->prepare(
            'DELETE FROM `' . esc_sql( $wpdb->prefix . 'accessiq_sessions' ) . '` WHERE created_at < %s',
            $cutoff
        ) );
        $wpdb->query( $wpdb->prepare(
            'DELETE FROM `' . esc_sql( $wpdb->prefix . 'accessiq_page_views' ) . '` WHERE created_at < %s',
            $cutoff
        ) );
        // phpcs:enable
    }
}