class RevisionHtmlRouteProvider

class RevisionHtmlRouteProvider implements EntityRouteProviderInterface {
    
    /**
     * {@inheritdoc}
     */
    public function getRoutes(EntityTypeInterface $entity_type) {
        $collection = new RouteCollection();
        $entityTypeId = $entity_type->id();
        if ($version_history_route = $this->getVersionHistoryRoute($entity_type)) {
            $collection->add("entity.{$entityTypeId}.version_history", $version_history_route);
        }
        if ($revision_view_route = $this->getRevisionViewRoute($entity_type)) {
            $collection->add("entity.{$entityTypeId}.revision", $revision_view_route);
        }
        if ($revision_revert_route = $this->getRevisionRevertRoute($entity_type)) {
            $collection->add("entity.{$entityTypeId}.revision_revert_form", $revision_revert_route);
        }
        if ($revision_delete_route = $this->getRevisionDeleteRoute($entity_type)) {
            $collection->add("entity.{$entityTypeId}.revision_delete_form", $revision_delete_route);
        }
        return $collection;
    }
    
    /**
     * Gets the entity revision history route.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entityType
     *   The entity type.
     *
     * @return \Symfony\Component\Routing\Route|null
     *   The entity revision revert route, or NULL if the entity type does not
     *   support viewing version history.
     */
    protected function getVersionHistoryRoute(EntityTypeInterface $entityType) : ?Route {
        if (!$entityType->hasLinkTemplate('version-history')) {
            return NULL;
        }
        $entityTypeId = $entityType->id();
        return (new Route($entityType->getLinkTemplate('version-history')))
            ->addDefaults([
            '_controller' => VersionHistoryController::class,
            '_title' => 'Revisions',
        ])
            ->setRequirement('_entity_access', $entityTypeId . '.view all revisions')
            ->setOption('entity_type_id', $entityTypeId)
            ->setOption('_admin_route', TRUE)
            ->setOption('parameters', [
            $entityTypeId => [
                'type' => 'entity:' . $entityTypeId,
            ],
        ]);
    }
    
    /**
     * Gets the entity revision view route.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entityType
     *   The entity type.
     *
     * @return \Symfony\Component\Routing\Route|null
     *   The entity revision view route, or NULL if the entity type does not
     *   support viewing revisions.
     */
    protected function getRevisionViewRoute(EntityTypeInterface $entityType) : ?Route {
        if (!$entityType->hasLinkTemplate('revision')) {
            return NULL;
        }
        $entityTypeId = $entityType->id();
        $revisionParameterName = $entityTypeId . '_revision';
        return (new Route($entityType->getLinkTemplate('revision')))
            ->addDefaults([
            '_controller' => EntityRevisionViewController::class,
            '_title_callback' => EntityRevisionViewController::class . '::title',
        ])
            ->setRequirement('_entity_access', $revisionParameterName . '.view revision')
            ->setOption('parameters', [
            $entityTypeId => [
                'type' => 'entity:' . $entityTypeId,
            ],
            $revisionParameterName => [
                'type' => 'entity_revision:' . $entityTypeId,
            ],
        ]);
    }
    
    /**
     * Gets the entity revision revert route.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entityType
     *   The entity type.
     *
     * @return \Symfony\Component\Routing\Route|null
     *   The entity revision revert route, or NULL if the entity type does not
     *   support reverting revisions.
     */
    protected function getRevisionRevertRoute(EntityTypeInterface $entityType) : ?Route {
        if (!$entityType->hasLinkTemplate('revision-revert-form')) {
            return NULL;
        }
        $entityTypeId = $entityType->id();
        $revisionParameterName = $entityTypeId . '_revision';
        return (new Route($entityType->getLinkTemplate('revision-revert-form')))
            ->addDefaults([
            '_entity_form' => $entityTypeId . '.revision-revert',
            '_title' => 'Revert revision',
        ])
            ->setRequirement('_entity_access', $revisionParameterName . '.revert')
            ->setOption('_admin_route', TRUE)
            ->setOption('parameters', [
            $entityTypeId => [
                'type' => 'entity:' . $entityTypeId,
            ],
            $revisionParameterName => [
                'type' => 'entity_revision:' . $entityTypeId,
            ],
        ]);
    }
    
    /**
     * Gets the entity revision delete route.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entityType
     *   The entity type.
     *
     * @return \Symfony\Component\Routing\Route|null
     *   The entity revision delete route, or NULL if the entity type does not
     *   support deleting revisions.
     */
    protected function getRevisionDeleteRoute(EntityTypeInterface $entityType) : ?Route {
        if (!$entityType->hasLinkTemplate('revision-delete-form')) {
            return NULL;
        }
        $entityTypeId = $entityType->id();
        $revisionParameterName = $entityTypeId . '_revision';
        return (new Route($entityType->getLinkTemplate('revision-delete-form')))
            ->addDefaults([
            '_entity_form' => $entityTypeId . '.revision-delete',
            '_title' => 'Delete revision',
        ])
            ->setRequirement('_entity_access', $revisionParameterName . '.delete revision')
            ->setOption('_admin_route', TRUE)
            ->setOption('parameters', [
            $entityTypeId => [
                'type' => 'entity:' . $entityTypeId,
            ],
            $revisionParameterName => [
                'type' => 'entity_revision:' . $entityTypeId,
            ],
        ]);
    }

}