Symfony2: poor man's date_range form type

DateRange.php

<?php

namespace Ormigo\Bundle\OrmigoBundle\Form\Model;

use DateTime;

class DateRange
{
    /**
     * @var DateTime
     */
    public $start;

    /**
     * @var DateTime
     */
    public $end;

    public function __construct(DateTime $start = null, DateTime $end = null)
    {
        if (!$start) {
            $start = new DateTime();
            $start->setTime(0, 0, 0);
        }

        if (!$end) {
            $end = new DateTime();
            $end->setTime(23, 59, 59);
        }

        $this->start = $start;
        $this->end = $end;
    }
}

DateRangeType.php

<?php

namespace Ormigo\Bundle\OrmigoBundle\Form\Type;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;

use Symfony\Component\OptionsResolver\Options;
use Symfony\Component\OptionsResolver\OptionsResolver;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

use Ormigo\Bundle\OrmigoBundle\Form\DataTransformer\DateRangeViewTransformer;
use Ormigo\Bundle\OrmigoBundle\Form\Validator\DateRangeValidator;

class DateRangeType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('start_date', 'date', array_merge_recursive(array(
                'property_path' => 'start',
                'widget' => 'single_text',
                'format' => 'yyyy-MM-dd',
                'model_timezone' => 'UTC',
                'view_timezone' => 'UTC',
                'attr' => array(
                    'data-type' => 'start',
                ),
            ), $options['start_options']))
            ->add('end_date', 'date', array_merge_recursive(array(
                'property_path' => 'end',
                'widget' => 'single_text',
                'format' => 'yyyy-MM-dd',
                'model_timezone' => 'UTC',
                'view_timezone' => 'UTC',
                'attr' => array(
                    'data-type' => 'end',
                ),
            ), $options['end_options']))
        ;

        $builder->addViewTransformer($options['transformer']);
        $builder->addEventSubscriber($options['validator']);
    }

    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'data_class' => 'Ormigo\Bundle\OrmigoBundle\Form\Model\DateRange',
            'end_options' => array(),
            'start_options' => array(),
            'transformer' => null,
            'validator' => null,
        ));

        $resolver->setAllowedTypes(array(
            'transformer' => 'Symfony\Component\Form\DataTransformerInterface',
            'validator' => 'Symfony\Component\EventDispatcher\EventSubscriberInterface',
        ));

        // Those normalizers lazily create the required objects, if none given.
        $resolver->setNormalizers(array(
            'transformer' => function (Options $options, $value) {
                if (!$value) {
                    $value = new DateRangeViewTransformer(new OptionsResolver());
                }

                return $value;
            },
            'validator' => function (Options $options, $value) {
                if (!$value) {
                    $value = new DateRangeValidator(new OptionsResolver());
                }

                return $value;
            },
        ));
    }

    public function getName()
    {
        return 'date_range';
    }
}

DateRangeValidator.php

<?php

namespace Ormigo\Bundle\OrmigoBundle\Form\Validator;

use DateTime;

use Symfony\Component\Form\FormError;
use Symfony\Component\Form\FormEvent;
use Symfony\Component\Form\FormEvents;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

class DateRangeValidator implements EventSubscriberInterface
{
    protected $options = array();

    public function __construct(OptionsResolverInterface $resolver, array $options = array())
    {
        $this->setDefaultOptions($resolver);
        $this->options = $resolver->resolve($options);
    }

    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'allow_end_in_past' => false,
            'allow_single_day' => true,
        ));

        $resolver->setAllowedValues(array(
            'allow_end_in_past' => array(true, false),
            'allow_single_day' => array(true, false),
        ));
    }

    public function onPostBind(FormEvent $event)
    {
        $form = $event->getForm();

        /* @var $dateRange \Ormigo\Bundle\OrmigoBundle\Form\Model\DateRange */
        $dateRange = $form->getNormData();

        if ($dateRange->start > $dateRange->end) {
            $form->addError(new FormError('date_range.invalid.end_before_start'));
        }

        if (!$this->options['allow_single_day'] and ($dateRange->start->format('Y-m-d') === $dateRange->end->format('Y-m-d'))) {
            $form->addError(new FormError('date_range.invalid.single_day'));
        }

        if (!$this->options['allow_end_in_past'] and ($dateRange->end < new DateTime())) {
            $form->addError(new FormError('date_range.invalid.end_in_past'));
        }
    }

    public static function getSubscribedEvents()
    {
        return array(
            FormEvents::POST_BIND => 'onPostBind',
        );
    }
}

DateRangeViewTransformer.php

<?php

namespace Ormigo\Bundle\OrmigoBundle\Form\DataTransformer;

use Symfony\Component\Form\DataTransformerInterface;
use Symfony\Component\Form\Exception\UnexpectedTypeException;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

use Ormigo\Bundle\OrmigoBundle\Form\Model\DateRange;

class DateRangeViewTransformer implements DataTransformerInterface
{
    protected $options = array();

    public function __construct(OptionsResolverInterface $resolver, array $options = array())
    {
        $this->setDefaultOptions($resolver);
        $this->options = $resolver->resolve($options);
    }

    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'include_end' => true,
        ));

        $resolver->setAllowedValues(array(
            'include_end' => array(true, false),
        ));
    }

    public function transform($value)
    {
        if (!$value) {
            return null;
        }

        if (!$value instanceof DateRange) {
            throw new UnexpectedTypeException($value, 'Ormigo\Bundle\OrmigoBundle\Form\Model\DateRange');
        }

        return $value;
    }

    public function reverseTransform($value)
    {
        if (!$value) {
            return null;
        }

        if (!$value instanceof DateRange) {
            throw new UnexpectedTypeException($value, 'Ormigo\Bundle\OrmigoBundle\Form\Model\DateRange');
        }

        if ($this->options['include_end']) {
            $value->end->setTime(23, 59, 59);
        }

        return $value;
    }
}

Just because this kind of form type is not packaged with the component :)