Callbacks

// src/EventListener/DataContainer/MakeTextNotMandatoryCallback.php
namespace App\EventListener\DataContainer;

use Contao\ContentModel;
use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;
use Symfony\Component\HttpFoundation\RequestStack;

#[AsCallback(table: 'tl_content', target: 'config.onload')]
class MakeTextNotMandatoryCallback
{
    private $requestStack;

    public function __construct(RequestStack $requestStack)
    {
        $this->requestStack = $requestStack;
    }

    public function __invoke(DataContainer $dc = null): void
    {
        if (null === $dc || !$dc->id || 'edit' !== $this->requestStack->getCurrentRequest()->query->get('act')) {
            return;
        }

        $element = ContentModel::findById($dc->id);

        if (null === $element || 'my_content_element' !== $element->type) {
            return;
        }

        $GLOBALS['TL_DCA']['tl_content']['fields']['text']['eval']['mandatory'] = false;
    }
}

// src/EventListener/DataContainer/NewsSubmitCallbackListener.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;
use Doctrine\DBAL\Connection;

#[AsCallback(table: 'tl_news', target: 'config.onsubmit')]
class NewsSubmitCallbackListener
{
    private $db;

    public function __construct(Connection $db)
    {
        $this->db = $db;
    }

    public function __invoke(DataContainer $dc): void
    {
        if (!$dc->id) {
            return;
        }

        $this->db->update('tl_news', ['foobar' => 'foo'], ['id' => $dc->id]);
    }
}

// src/EventListener/DataContainer/MemberDeleteCallbackListener.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;
use Doctrine\DBAL\Connection;

#[AsCallback(table: 'tl_member', target: 'config.ondelete')]
class MemberDeleteCallbackListener
{
    private $db;

    public function __construct(Connection $db)
    {
        $this->db = $db;
    }

    public function __invoke(DataContainer $dc, int $undoId): void
    {
        if (!$dc->id) {
            return;
        }

        $this->db->delete('tl_foobar', ['member' => (int) $dc->id]);
    }
}

// src/EventListener/DataContainer/PagePaletteCallback.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DataContainer\PaletteManipulator;
use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;

#[AsCallback(table: 'tl_page', target: 'config.onpalette')]
class PagePaletteCallback
{
    public function __invoke(string $palette, DataContainer $dc): string
    {
        $currentRecord = $dc->getCurrentRecord();

        // This shouldn't happen, defensive programming
        if (null === $currentRecord) {
            return $palette;
        }

        // Adjust palettes for root pages
        if ('root' === $currentRecord['type']) {
            $palette = PaletteManipulator::create()
                ->addLegend('my_legend')
                ->addField(['my_field_one', 'my_field_two'], 'my_legend', PaletteManipulator::POSITION_APPEND)
                ->applyToString($palette)
            ;
        }
        
        return $palette;
    }
}

// src/EventListener/DataContainer/CalendarHeaderCallback.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;
use Doctrine\DBAL\Connection;

/**
 * Adds the total number of events to the header fields.
 */
#[AsCallback(table: 'tl_calendar_events', target: 'list.sorting.header')]
class CalendarHeaderCallback
{
    /** @var Connection */
    private $db;

    public function __construct(Connection $db)
    {
        $this->db = $db;
    }

    public function __invoke(array $labels, DataContainer $dc): array
    {
        $count = $this->db->fetchOne("SELECT COUNT(*) FROM tl_calendar_events WHERE pid = ?", [$dc->id]);

        $labels['Total events'] = $count;

        return $labels;
    }
}

// src/EventListener/DataContainer/ExampleLabelCallbackListener.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;
use Contao\Image;

#[AsCallback(table: 'tl_example', target: 'list.label.label')]
class ExampleLabelCallbackListener
{
    public function __invoke(array $row, string $label, DataContainer $dc, string $imageAttribute = '', bool $returnImage = false, ?bool $isProtected = null): string
    {
        $icon = Image::getHtml('bundles/app/images/example.svg');

        return $icon.sprintf(' %s <span class="tl_gray" style="margin-left:3px;">[%s]</span>', $row['title'], $row['name']);
    }
}

// src/EventListener/DataContainer/ExampleLabelCallbackListener.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;
use Symfony\Contracts\Translation\TranslatorInterface;

#[AsCallback(table: 'tl_example', target: 'list.label.label')]
class ExampleLabelCallbackListener
{
    private TranslatorInterface $translator;

    public function __construct(TranslatorInterface $translator)
    {
        $this->translator = $translator;
    }
    
    public function __invoke(array $row, string $label, DataContainer $dc, array $labels): array
    {
        $fieldName = 'status';
        $fields = $GLOBALS['TL_DCA'][$dc->table]['list']['label']['fields'];
        $key = array_search($fieldName, $fields, true);

        $labels[$key] = $this->translator->trans('tl_example.status_option.'.$labels[$key], [], 'contao_tl_example') ?? $this->translator->trans('tl_example.status_option_unknown', [], 'contao_tl_example');

        return $labels;
    }
}

// src/EventListener/DataContainer/ExampleListOperationListener.php
namespace App\EventListener\DataContainer;

use Contao\Backend;
use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;
use Contao\Image;
use Contao\StringUtil;
use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;

#[AsCallback(table: 'tl_example', target: 'list.operations.custom.button')]
class ExampleListOperationListener
{
    public function __construct(
        private readonly AuthorizationCheckerInterface $authorizationChecker,
    ) {
    }

    public function __invoke(
        array $row,
        ?string $href,
        string $label,
        string $title,
        ?string $icon,
        string $attributes,
        string $table,
        array $rootRecordIds,
        ?array $childRecordIds,
        bool $circularReference,
        ?string $previous,
        ?string $next,
        DataContainer $dc
    ): string
    {
        if (!$this->authorizationChecker->isGranted('contao_user.example', 'custom_operation')) {
            return '';
        }

        return sprintf(
            '<a href="%s" title="%s"%s>%s</a> ',
            Backend::addToUrl($href . '&amp;id=' . $row['id']),
            StringUtil::specialchars($title),
            $attributes,
            Image::getHtml($icon, $label)
        );
    }
}

// src/EventListener/DataContainer/AttributesCallback.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;

#[AsCallback('tl_content', 'fields.text.attributes')]
class AttributesCallback
{
    public function __invoke(array $attributes, DataContainer|null $dc = null): array
    {
        if (!$dc || 'text' !== ($dc->getCurrentRecord()['type'] ?? null)) {
            return $attributes;
        }

        $attributes['label'] = 'Custom text label';

        return $attributes;
    }
}

// src/EventListener/DataContainer/ContentTextSaveCallback.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;

#[AsCallback(table: 'tl_content', target: 'fields.text.save')]
class ContentTextSaveCallback
{
    public function __invoke($value, DataContainer $dc)
    {
        // Show an error if tl_content.text contains "foobar"
        if (false !== stripos($value, 'foobar')) {
            throw new \Exception('String "foobar" is not allowed.');
        }

        // Or process the value before saving
        $value = strtoupper($value);

        // Return the processed value
        return $value;
    }
}

// src/EventListener/DataContainer/ExampleSerpPreviewUrlCallbackListener.php
namespace App\EventListener\DataContainer;

use App\Model\ExampleCategoryModel;
use App\Model\ExampleModel;
use Contao\Config;
use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\PageModel;

#[AsCallback(table: 'tl_example', target: 'fields.serpPreview.eval.url')]
class ExampleSerpPreviewUrlCallbackListener
{
    public function __invoke(ExampleModel $model): string
    {
        /** @var ExampleCategoryModel $category */
        $category = $model->getRelated('pid');

        if (null === $category) {
            throw new \Exception('Invalid category');
        }

        /** @var PageModel $page */
        $page = $category->getRelated('jumpTo');

        if (null === $page) {
            throw new \Exception('Invalid jumpTo page');
        }

        $suffix = $page->getAbsoluteUrl(Config::get('useAutoItem') ? '/%s' : '/items/%s');

        return sprintf(preg_replace('/%(?!s)/', '%%', $suffix), $model->alias ?: $model->id);
    }
}

// src/EventListener/DataContainer/ExampleSerpPreviewTitleTagCallbackListener.php
namespace App\EventListener\DataContainer;

use App\Model\ExampleCategoryModel;
use App\Model\ExampleModel;
use Contao\Controller;
use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\LayoutModel;
use Contao\PageModel;

#[AsCallback(table: 'tl_example', target: 'fields.serpPreview.eval.title_tag')]
class ExampleSerpPreviewTitleTagCallbackListener
{
    public function __invoke(ExampleModel $model): string
    {
        /** @var ExampleCategoryModel $category */
        $category = $model->getRelated('pid');

        if (null === $category) {
            return '';
        }

        /** @var PageModel $page */
        $page = $category->getRelated('jumpTo');

        if (null === $page) {
            return '';
        }

        $page->loadDetails();

        /** @var LayoutModel $layout */
        $layout = $page->getRelated('layout');

        if (null === $layout) {
            return '';
        }

        global $objPage;
        $objPage = $page;

        return Controller::replaceInsertTags(str_replace('{{page::pageTitle}}', '%s', $layout->titleTag ?: '{{page::pageTitle}} - {{page::rootPageTitle}}'));
    }
}

// src/EventListener/DataContainer/EditButtonsCallbackListener.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;

#[AsCallback(table: 'tl_example', target: 'edit.buttons')]
class EditButtonsCallbackListener
{
    public function __invoke(array $buttons, DataContainer $dc): array
    {
        // Remove the "Save and close" button
        unset($buttons['saveNclose']);

        return $buttons;
    }
}

// src/EventListener/DataContainer/SelectButtonsCallbackListener.php
namespace App\EventListener\DataContainer;

use Contao\CoreBundle\DependencyInjection\Attribute\AsCallback;
use Contao\DataContainer;

#[AsCallback(table: 'tl_example', target: 'select.buttons')]
class SelectButtonsCallbackListener
{
    public function __invoke(array $buttons, DataContainer $dc): array
    {
        // Remove the delete button
        unset($buttons['delete']);
        
        return $buttons;
    }
}