<?php
defined( 'ABSPATH' ) || exit;

/**
 * Class AISP_Customer_Activity_Cron
 *
 * Hidden background cleanup — removes tracking data for customers
 * inactive longer than (activity_hours + 30 days).
 *
 * When activity_hours === 0 (All), the cron is disabled entirely.
 */
class AISP_Customer_Activity_Cron {

	const HOOK = 'aisp_customer_activity_cleanup';

	/** Safety buffer added on top of activity_hours before deleting data. */
	const BUFFER_DAYS = 30;

	public static function init() {
		add_action( 'init',     [ __CLASS__, 'schedule' ] );
		add_action( self::HOOK, [ __CLASS__, 'run_cleanup' ] );

		// Re-evaluate schedule when activity_hours changes.
		add_action( 'update_option_aisp_ca_activity_hours', [ __CLASS__, 'on_hours_updated' ], 10, 2 );
	}

	// -------------------------------------------------------------------------
	// Scheduling
	// -------------------------------------------------------------------------

	public static function schedule() {
		$hours = (int) get_option( 'aisp_ca_activity_hours', 72 );

		if ( $hours === 0 ) {
			// "All" selected — disable cron, keep all data forever.
			self::unschedule();
			return;
		}

		if ( ! wp_next_scheduled( self::HOOK ) ) {
			wp_schedule_event( time(), 'daily', self::HOOK );
		}
	}

	public static function on_hours_updated( $old_value, $new_value ) {
		if ( (int) $new_value === 0 ) {
			self::unschedule();
		} elseif ( ! wp_next_scheduled( self::HOOK ) ) {
			wp_schedule_event( time(), 'daily', self::HOOK );
		}
	}

	private static function unschedule() {
		$timestamp = wp_next_scheduled( self::HOOK );
		if ( $timestamp ) {
			wp_unschedule_event( $timestamp, self::HOOK );
		}
	}

	// -------------------------------------------------------------------------
	// Cleanup
	// -------------------------------------------------------------------------

	public static function run_cleanup() {
		$hours = (int) get_option( 'aisp_ca_activity_hours', 72 );

		// Safety net — never run when "All" is selected.
		if ( $hours === 0 ) {
			return;
		}

		// Delete data older than activity_hours + 30-day buffer.
		$retention_seconds = ( $hours * HOUR_IN_SECONDS ) + ( self::BUFFER_DAYS * DAY_IN_SECONDS );
		$limit_time        = current_time( 'timestamp' ) - $retention_seconds;

		$tracked_roles = AISP_Customer_Activity_Settings::get_tracked_roles();

		if ( empty( $tracked_roles ) ) {
			return;
		}

		$users = get_users( [
			'role__in'   => $tracked_roles,
			// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
			'meta_query' => [
				[
					'key'     => 'aisp_ca_last_activity',
					'compare' => 'EXISTS',
				],
			],
			'fields' => [ 'ID' ],
		] );

		if ( empty( $users ) ) {
			return;
		}

		foreach ( $users as $user ) {
			$last_activity = (int) get_user_meta( $user->ID, 'aisp_ca_last_activity', true );
			if ( $last_activity && $last_activity < $limit_time ) {
				AISP_Customer_Activity_Tracker::delete_user_metas( $user->ID );
			}
		}

		// Invalidate cache after bulk cleanup.
		AISP_Customer_Activity_Tracker::invalidate_cache();
	}
}