Symfony 3 forms validation constraints without an entity

SymfonyCustomFormTypeWithValidation.php

<?php

// ...

use Doctrine\Common\Collections\ArrayCollection;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\Extension\Core\Type\CheckboxType;
use Symfony\Component\Form\Extension\Core\Type\ChoiceType;
use Symfony\Component\Form\Extension\Core\Type\PasswordType;
use Symfony\Component\Form\Extension\Core\Type\RepeatedType;
use Symfony\Component\Form\Extension\Core\Type\SubmitType;
use Symfony\Component\Form\Extension\Core\Type\TextType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolver;
use Symfony\Component\Validator\Constraints\Callback;
use Symfony\Component\Validator\Context\ExecutionContextInterface;

class SubscriptionUserType extends AbstractType
{
    /**
     * @var ArrayCollection<DataSubscription>
     */
    private $dataSubscriptions;

    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $this->dataSubscriptions = $options['data_subscriptions'];

        // Shared user
        $builder->add('username', TextType::class, [
            'attr'     => [
                'pattern' => '[a-z][a-z0-9\.\_\-]{1,29}[a-z0-9]',
            ],
            'required' => true,
        ]);

        $builder->add('subscriptionId', ChoiceType::class, [
            'label'    => 'Subscription',
            'choices'  => $this->buildSubscriptionChoices($this->dataSubscriptions),
            'required' => true,
        ]);

        // Email data
        $builder->add('hasEmail', CheckboxType::class, [
            'label'    => 'Create email address?',
            'required' => false,
        ]);

        $builder->add('emailPassword', RepeatedType::class, [
            'type'            => PasswordType::class,
            'invalid_message' => 'The passwords must match.',
            'first_options'   => [
                'label' => 'Password',
                'attr'  => [
                    'pattern' => '^(?=.*[a-z]+.*)(?=.*[A-Z]+.*)(?=.*[0-9]+.*)(?=.*[\@\#\$\%\^\*\~\-\=\_\+\[\]\\\{\}\:\,\/\?]+.*)[0-9a-zA-Z\@\#\$\%\^\*\~\-\=\_\+\[\]\\\{\}\:\,\/\?]{8,12}$',
                ],
            ],
            'second_options'  => [
                'label' => 'Confirm password',
            ],
        ]);

        // Webspace data
        $builder->add('hasWebspace', CheckboxType::class, [
            'label'    => 'Create webspace?',
            'required' => false,
        ]);
        $builder->add('webspacePassword', RepeatedType::class, [
            'type'            => PasswordType::class,
            'invalid_message' => 'The passwords must match.',
            'first_options'   => [
                'label' => 'Password',
                'attr'  => [
                    'pattern' => '^(?=.*[a-z]+.*)(?=.*[A-Z]+.*)(?=.*[0-9]+.*)(?=.*[\@\#\$\%\^\*\~\-\=\_\+\[\]\\\{\}\:\,\/\?]+.*)[0-9a-zA-Z\@\#\$\%\^\*\~\-\=\_\+\[\]\\\{\}\:\,\/\?]{8,12}$',
                ],
            ],
            'second_options'  => [
                'label' => 'Confirm password',
            ],
        ]);

        // Save button
        $builder->add('save', SubmitType::class);
    }

    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults([
            'data_class'         => SubscriptionUser::class,
            'constraints'        => [
                new Callback([
                    'callback' => [$this, 'checkSubscription'],
                ]),
                new Callback([
                    'callback' => [$this, 'checkSelectedOptions'],
                ]),
                new Callback([
                    'callback' => [$this, 'checkEmailPassword'],
                ]),
                new Callback([
                    'callback' => [$this, 'checkWebspacePassword'],
                ]),
            ],
            'csrf_protection'    => true,
            'csrf_field_name'    => '_token',
            'intention'          => 'subscription_user',
            'data_subscriptions' => [],
        ]);
    }

    public function buildSubscriptionChoices($dataSubscriptions)
    {
        $choices = [];
        foreach ($dataSubscriptions as $dataSubscription) {
            if ($dataSubscription->hasEmailAddressAvailable() || $dataSubscription->hasWebspaceAvailable()) {
                $label =  sprintf(
                    '#%s - %s [%s/%s]',
                    $dataSubscription->getId(),
                    $dataSubscription->getMacAddress(),
                    $dataSubscription->getEmailAddressesAvailable(),
                    $dataSubscription->getWebspacesAvailable()
                );

                $choices[$label] = $dataSubscription->getId();
            }
        }

        return $choices;
    }

    public function checkSubscription($data, ExecutionContextInterface $context)
    {
        $dataSubscription = $this->dataSubscriptions->get($data->getSubscriptionId());
        if (!$dataSubscription) {
            $context->buildViolation('Invalid subscription selected!')
                ->atPath('subscriptionId')
                ->addViolation();
            return;
        }

        if ($data->hasEmail() && !$dataSubscription->hasEmailAddressAvailable()) {
            $context->buildViolation('The selected subscription has no email address available!')
                ->atPath('subscriptionId')
                ->addViolation();
        }

        if ($data->hasWebspace() && !$dataSubscription->hasWebspaceAvailable()) {
            $context->buildViolation('The selected subscription has no webspace available!')
                ->atPath('subscriptionId')
                ->addViolation();
        }
    }

    public function checkSelectedOptions($data, ExecutionContextInterface $context)
    {
        if ($data->hasEmail() === false && $data->hasWebspace() === false) {
            $context->buildViolation('At least one of the options create email or webspace must be selected!')
                ->addViolation();
        }
    }

    public function checkEmailPassword($data, ExecutionContextInterface $context)
    {
        if ($data->hasEmail() === true && !$data->getEmailPassword()) {
            $context->buildViolation('Email password is not set!')
                ->atPath('emailPassword')
                ->addViolation();
        }
    }

    public function checkWebspacePassword($data, ExecutionContextInterface $context)
    {
        if ($data->hasWebspace() === true && !$data->getWebspacePassword()) {
            $context->buildViolation('Webspace password is not set!')
                ->atPath('webspacePassword')
                ->addViolation();
        }
    }

    public function getBlockPrefix()
    {
        return 'selfcare_subscription_user';
    }
}

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