Day, month and year validation rules for Laravel 5.4

Validator.php

<?php

namespace App\Http\Requests;

class Validator
{

    /**
     * Validate that an attribute is a valid day.
     *
     * @param   string  $attribute
     * @param   int     $day
     *
     * @return  bool
     */
    public function validateDay($attribute, $day)
    {
        return is_numeric($day) && $day > 0 && $day < 32;
    }

    /**
     * Validate that an attribute is month.
     *
     * @param   string  $attribute
     * @param   int     $month
     * @param   array   $parameters
     * @param   \Illuminate\Support\Facades\Validator   $validator
     *
     * @return  bool
     */
    public function validateMonth($attribute, $month, $parameters, $validator)
    {
        $day = $validator->getData()[$parameters[0]];

        if (! $day or ! is_numeric($month) or $month < 1 or $month > 12) {
            return false;
        }

        switch ($month) {
            case 2:
                return $day < 30;

            case 4:
            case 6:
            case 9:
            case 11:
                return $day < 31;

            default:
                return $day < 32;
        }
    }

    /**
     * Validate that an attribute is a valid year.
     *
     *
     * @param   string  $attribute
     * @param   int     $year
     * @param   array   $parameters
     * @param   \Illuminate\Support\Facades\Validator   $validator
     *
     * @return  bool
     */
    public function validateYear($attribute, $year, $parameters, $validator)
    {
        if (! is_numeric($year) or $year < 1910 or $year > date('Y') - 3) {
            return false;
        }

        $data = $validator->getData();

        if (! $day = $data[$parameters[0]] or ! $month = $data[$parameters[1]]) {
            return false;
        }

        return ! ($year % 4 && $month == 2 && $day == 29);
    }

}