<?php

namespace Symfony\Components\Validator\Constraints;

use Symfony\Components\Validator\Constraint;
use Symfony\Components\Validator\ConstraintValidator;
use Symfony\Components\Validator\Exception\UnexpectedTypeException;

class DateValidator extends ConstraintValidator
{
  const PATTERN = '/^(\d{4})-(\d{2})-(\d{2})$/';

  public function isValid($value, Constraint $constraint)
  {
    if ($value === null)
    {
      return true;
    }

    if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString()')))
    {
      throw new UnexpectedTypeException($value, 'string');
    }

    $value = (string)$value;

    if (!preg_match(self::PATTERN, $value, $matches))
    {
      $this->setMessage($constraint->message, array('value' => $value));

      return false;
    }

    return checkdate($matches[2], $matches[3], $matches[1]);
  }
}