Custom Hook Limit / 4 hours

/**
 * Add Custom Hook Limit
 * @version 1.0
 */
function mycred_pro_add_custom_hook_limit( $limits ) {

    $limits['h'] = '4 hours';

    return $limits;

}
add_filter( 'mycred_hook_limits', 'mycred_pro_add_custom_hook_limit' );

/**
 * Enforce Custom Hook Limit
 * @version 1.0
 */
function mycred_pro_run_custom_hook_limit( $over_limit, $instance, $reference, $user_id, $ref_id, $hook ) {

    // Only applicable for the "Viewing Content" hook
    if ( $reference != 'view_content' ) return $over_limit;

    // Prefs
    $prefs             = $this->prefs[ $instance ]['limit'];

    // No limit is set, bail
    if ( $prefs == '0/x' ) return $over_limit;

    $prefs             = explode( '/', $prefs );

    // Some other limit is used, bail
    if ( $prefs[1] != 'h' ) return $over_limit;

    $maximum           = $prefs[0];

    // Get the timestamp for 4 hours ago
    $four_hours_ago    = current_time( 'timestamp' ) - ( 4 * HOUR_IN_SECONDS );

    global $wpdb, $mycred_log_table;

    $total_last4_hours = $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM {$mycred_log_table} WHERE ref = %s AND user_id = %d AND time >= %d;", $reference, $user_id, $four_hours_ago ) );

    // Check if we are over the limit
    if ( $total_last4_hours >= $maximum ) return false;

    return true;

}
add_filter( 'mycred_over_hook_limit', 'mycred_pro_run_custom_hook_limit', 10, 6 );