class EntityViewsData

class EntityViewsData implements EntityHandlerInterface, EntityViewsDataInterface {
    use StringTranslationTrait;
    use DeprecatedServicePropertyTrait;
    
    /**
     * {@inheritdoc}
     */
    protected $deprecatedProperties = [
        'entityManager' => 'entity.manager',
    ];
    
    /**
     * Entity type for this views data handler instance.
     *
     * @var \Drupal\Core\Entity\EntityTypeInterface
     */
    protected $entityType;
    
    /**
     * The storage used for this entity type.
     *
     * @var \Drupal\Core\Entity\Sql\SqlEntityStorageInterface
     */
    protected $storage;
    
    /**
     * The module handler.
     *
     * @var \Drupal\Core\Extension\ModuleHandlerInterface
     */
    protected $moduleHandler;
    
    /**
     * The translation manager.
     *
     * @var \Drupal\Core\StringTranslation\TranslationInterface
     */
    protected $translationManager;
    
    /**
     * The field storage definitions for all base fields of the entity type.
     *
     * @var \Drupal\Core\Field\FieldStorageDefinitionInterface[]
     */
    protected $fieldStorageDefinitions;
    
    /**
     * The entity type manager.
     *
     * @var \Drupal\Core\Entity\EntityTypeManagerInterface
     */
    protected $entityTypeManager;
    
    /**
     * The entity field manager.
     *
     * @var \Drupal\Core\Entity\EntityFieldManagerInterface
     */
    protected $entityFieldManager;
    
    /**
     * Constructs an EntityViewsData object.
     *
     * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
     *   The entity type to provide views integration for.
     * @param \Drupal\Core\Entity\Sql\SqlEntityStorageInterface $storage_controller
     *   The storage handler used for this entity type.
     * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
     *   The entity type manager.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
     *   The module handler.
     * @param \Drupal\Core\StringTranslation\TranslationInterface $translation_manager
     *   The translation manager.
     * @param \Drupal\Core\Entity\EntityFieldManagerInterface $entity_field_manager
     *   The entity field manager.
     */
    public function __construct(EntityTypeInterface $entity_type, SqlEntityStorageInterface $storage_controller, EntityTypeManagerInterface $entity_type_manager, ModuleHandlerInterface $module_handler, TranslationInterface $translation_manager, EntityFieldManagerInterface $entity_field_manager = NULL) {
        $this->entityType = $entity_type;
        $this->entityTypeManager = $entity_type_manager;
        $this->storage = $storage_controller;
        $this->moduleHandler = $module_handler;
        $this->setStringTranslation($translation_manager);
        if (!$entity_field_manager) {
            @trigger_error('Calling EntityViewsData::__construct() with the $entity_field_manager argument is supported in drupal:8.8.0 and will be required before drupal:9.0.0. See https://www.drupal.org/node/2549139.', E_USER_DEPRECATED);
            $entity_field_manager = \Drupal::service('entity_field.manager');
        }
        $this->entityFieldManager = $entity_field_manager;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
        return new static($entity_type, $container->get('entity_type.manager')
            ->getStorage($entity_type->id()), $container->get('entity_type.manager'), $container->get('module_handler'), $container->get('string_translation'), $container->get('entity_field.manager'));
    }
    
    /**
     * Gets the field storage definitions.
     *
     * @return \Drupal\Core\Field\FieldStorageDefinitionInterface[]
     */
    protected function getFieldStorageDefinitions() {
        if (!isset($this->fieldStorageDefinitions)) {
            $this->fieldStorageDefinitions = $this->entityFieldManager
                ->getFieldStorageDefinitions($this->entityType
                ->id());
        }
        return $this->fieldStorageDefinitions;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getViewsData() {
        $data = [];
        $base_table = $this->entityType
            ->getBaseTable() ?: $this->entityType
            ->id();
        $views_revision_base_table = NULL;
        $revisionable = $this->entityType
            ->isRevisionable();
        $base_field = $this->entityType
            ->getKey('id');
        $revision_table = '';
        if ($revisionable) {
            $revision_table = $this->entityType
                ->getRevisionTable() ?: $this->entityType
                ->id() . '_revision';
        }
        $translatable = $this->entityType
            ->isTranslatable();
        $data_table = '';
        if ($translatable) {
            $data_table = $this->entityType
                ->getDataTable() ?: $this->entityType
                ->id() . '_field_data';
        }
        // Some entity types do not have a revision data table defined, but still
        // have a revision table name set in
        // \Drupal\Core\Entity\Sql\SqlContentEntityStorage::initTableLayout() so we
        // apply the same kind of logic.
        $revision_data_table = '';
        if ($revisionable && $translatable) {
            $revision_data_table = $this->entityType
                ->getRevisionDataTable() ?: $this->entityType
                ->id() . '_field_revision';
        }
        $revision_field = $this->entityType
            ->getKey('revision');
        // Setup base information of the views data.
        $data[$base_table]['table']['group'] = $this->entityType
            ->getLabel();
        $data[$base_table]['table']['provider'] = $this->entityType
            ->getProvider();
        $views_base_table = $base_table;
        if ($data_table) {
            $views_base_table = $data_table;
        }
        $data[$views_base_table]['table']['base'] = [
            'field' => $base_field,
            'title' => $this->entityType
                ->getLabel(),
            'cache_contexts' => $this->entityType
                ->getListCacheContexts(),
            'access query tag' => $this->entityType
                ->id() . '_access',
        ];
        $data[$base_table]['table']['entity revision'] = FALSE;
        if ($label_key = $this->entityType
            ->getKey('label')) {
            if ($data_table) {
                $data[$views_base_table]['table']['base']['defaults'] = [
                    'field' => $label_key,
                    'table' => $data_table,
                ];
            }
            else {
                $data[$views_base_table]['table']['base']['defaults'] = [
                    'field' => $label_key,
                ];
            }
        }
        // Entity types must implement a list_builder in order to use Views'
        // entity operations field.
        if ($this->entityType
            ->hasListBuilderClass()) {
            $data[$base_table]['operations'] = [
                'field' => [
                    'title' => $this->t('Operations links'),
                    'help' => $this->t('Provides links to perform entity operations.'),
                    'id' => 'entity_operations',
                ],
            ];
            if ($revision_table) {
                $data[$revision_table]['operations'] = [
                    'field' => [
                        'title' => $this->t('Operations links'),
                        'help' => $this->t('Provides links to perform entity operations.'),
                        'id' => 'entity_operations',
                    ],
                ];
            }
        }
        if ($this->entityType
            ->hasViewBuilderClass()) {
            $data[$base_table]['rendered_entity'] = [
                'field' => [
                    'title' => $this->t('Rendered entity'),
                    'help' => $this->t('Renders an entity in a view mode.'),
                    'id' => 'rendered_entity',
                ],
            ];
        }
        // Setup relations to the revisions/property data.
        if ($data_table) {
            $data[$base_table]['table']['join'][$data_table] = [
                'left_field' => $base_field,
                'field' => $base_field,
                'type' => 'INNER',
            ];
            $data[$data_table]['table']['group'] = $this->entityType
                ->getLabel();
            $data[$data_table]['table']['provider'] = $this->entityType
                ->getProvider();
            $data[$data_table]['table']['entity revision'] = FALSE;
        }
        if ($revision_table) {
            $data[$revision_table]['table']['group'] = $this->t('@entity_type revision', [
                '@entity_type' => $this->entityType
                    ->getLabel(),
            ]);
            $data[$revision_table]['table']['provider'] = $this->entityType
                ->getProvider();
            $views_revision_base_table = $revision_table;
            if ($revision_data_table) {
                $views_revision_base_table = $revision_data_table;
            }
            $data[$views_revision_base_table]['table']['entity revision'] = TRUE;
            $data[$views_revision_base_table]['table']['base'] = [
                'field' => $revision_field,
                'title' => $this->t('@entity_type revisions', [
                    '@entity_type' => $this->entityType
                        ->getLabel(),
                ]),
            ];
            // Join the revision table to the base table.
            $data[$views_revision_base_table]['table']['join'][$views_base_table] = [
                'left_field' => $revision_field,
                'field' => $revision_field,
                'type' => 'INNER',
            ];
            if ($revision_data_table) {
                $data[$revision_data_table]['table']['group'] = $this->t('@entity_type revision', [
                    '@entity_type' => $this->entityType
                        ->getLabel(),
                ]);
                $data[$revision_data_table]['table']['entity revision'] = TRUE;
                $data[$revision_table]['table']['join'][$revision_data_table] = [
                    'left_field' => $revision_field,
                    'field' => $revision_field,
                    'type' => 'INNER',
                ];
            }
            // Add a filter for showing only the latest revisions of an entity.
            $data[$revision_table]['latest_revision'] = [
                'title' => $this->t('Is Latest Revision'),
                'help' => $this->t('Restrict the view to only revisions that are the latest revision of their entity.'),
                'filter' => [
                    'id' => 'latest_revision',
                ],
            ];
            if ($this->entityType
                ->isTranslatable()) {
                $data[$revision_table]['latest_translation_affected_revision'] = [
                    'title' => $this->t('Is Latest Translation Affected Revision'),
                    'help' => $this->t('Restrict the view to only revisions that are the latest translation affected revision of their entity.'),
                    'filter' => [
                        'id' => 'latest_translation_affected_revision',
                    ],
                ];
            }
        }
        $this->addEntityLinks($data[$base_table]);
        if ($views_revision_base_table) {
            $this->addEntityLinks($data[$views_revision_base_table]);
        }
        // Load all typed data definitions of all fields. This should cover each of
        // the entity base, revision, data tables.
        $field_definitions = $this->entityFieldManager
            ->getBaseFieldDefinitions($this->entityType
            ->id());
        
        /** @var \Drupal\Core\Entity\Sql\DefaultTableMapping $table_mapping */
        if ($table_mapping = $this->storage
            ->getTableMapping($field_definitions)) {
            // Fetch all fields that can appear in both the base table and the data
            // table.
            $entity_keys = $this->entityType
                ->getKeys();
            $duplicate_fields = array_intersect_key($entity_keys, array_flip([
                'id',
                'revision',
                'bundle',
            ]));
            // Iterate over each table we have so far and collect field data for each.
            // Based on whether the field is in the field_definitions provided by the
            // entity manager.
            // @todo We should better just rely on information coming from the entity
            //   storage.
            // @todo https://www.drupal.org/node/2337511
            foreach ($table_mapping->getTableNames() as $table) {
                foreach ($table_mapping->getFieldNames($table) as $field_name) {
                    // To avoid confusing duplication in the user interface, for fields
                    // that are on both base and data tables, only add them on the data
                    // table (same for revision vs. revision data).
                    if ($data_table && ($table === $base_table || $table === $revision_table) && in_array($field_name, $duplicate_fields)) {
                        continue;
                    }
                    $this->mapFieldDefinition($table, $field_name, $field_definitions[$field_name], $table_mapping, $data[$table]);
                }
            }
            foreach ($field_definitions as $field_definition) {
                if ($table_mapping->requiresDedicatedTableStorage($field_definition->getFieldStorageDefinition())) {
                    $table = $table_mapping->getDedicatedDataTableName($field_definition->getFieldStorageDefinition());
                    $data[$table]['table']['group'] = $this->entityType
                        ->getLabel();
                    $data[$table]['table']['provider'] = $this->entityType
                        ->getProvider();
                    $data[$table]['table']['join'][$views_base_table] = [
                        'left_field' => $base_field,
                        'field' => 'entity_id',
                        'extra' => [
                            [
                                'field' => 'deleted',
                                'value' => 0,
                                'numeric' => TRUE,
                            ],
                        ],
                    ];
                    if ($revisionable) {
                        $revision_table = $table_mapping->getDedicatedRevisionTableName($field_definition->getFieldStorageDefinition());
                        $data[$revision_table]['table']['group'] = $this->t('@entity_type revision', [
                            '@entity_type' => $this->entityType
                                ->getLabel(),
                        ]);
                        $data[$revision_table]['table']['provider'] = $this->entityType
                            ->getProvider();
                        $data[$revision_table]['table']['join'][$views_revision_base_table] = [
                            'left_field' => $revision_field,
                            'field' => 'entity_id',
                            'extra' => [
                                [
                                    'field' => 'deleted',
                                    'value' => 0,
                                    'numeric' => TRUE,
                                ],
                            ],
                        ];
                    }
                }
            }
        }
        // Add the entity type key to each table generated.
        $entity_type_id = $this->entityType
            ->id();
        array_walk($data, function (&$table_data) use ($entity_type_id) {
            $table_data['table']['entity type'] = $entity_type_id;
        });
        return $data;
    }
    
    /**
     * Sets the entity links in case corresponding link templates exist.
     *
     * @param array $data
     *   The views data of the base table.
     */
    protected function addEntityLinks(array &$data) {
        $entity_type_id = $this->entityType
            ->id();
        $t_arguments = [
            '@entity_type_label' => $this->entityType
                ->getLabel(),
        ];
        if ($this->entityType
            ->hasLinkTemplate('canonical')) {
            $data['view_' . $entity_type_id] = [
                'field' => [
                    'title' => $this->t('Link to @entity_type_label', $t_arguments),
                    'help' => $this->t('Provide a view link to the @entity_type_label.', $t_arguments),
                    'id' => 'entity_link',
                ],
            ];
        }
        if ($this->entityType
            ->hasLinkTemplate('edit-form')) {
            $data['edit_' . $entity_type_id] = [
                'field' => [
                    'title' => $this->t('Link to edit @entity_type_label', $t_arguments),
                    'help' => $this->t('Provide an edit link to the @entity_type_label.', $t_arguments),
                    'id' => 'entity_link_edit',
                ],
            ];
        }
        if ($this->entityType
            ->hasLinkTemplate('delete-form')) {
            $data['delete_' . $entity_type_id] = [
                'field' => [
                    'title' => $this->t('Link to delete @entity_type_label', $t_arguments),
                    'help' => $this->t('Provide a delete link to the @entity_type_label.', $t_arguments),
                    'id' => 'entity_link_delete',
                ],
            ];
        }
    }
    
    /**
     * Puts the views data for a single field onto the views data.
     *
     * @param string $table
     *   The table of the field to handle.
     * @param string $field_name
     *   The name of the field to handle.
     * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
     *   The field definition defined in Entity::baseFieldDefinitions()
     * @param \Drupal\Core\Entity\Sql\TableMappingInterface $table_mapping
     *   The table mapping information
     * @param array $table_data
     *   A reference to a specific entity table (for example data_table) inside
     *   the views data.
     */
    protected function mapFieldDefinition($table, $field_name, FieldDefinitionInterface $field_definition, TableMappingInterface $table_mapping, &$table_data) {
        // Create a dummy instance to retrieve property definitions.
        $field_column_mapping = $table_mapping->getColumnNames($field_name);
        $field_schema = $this->getFieldStorageDefinitions()[$field_name]
            ->getSchema();
        $field_definition_type = $field_definition->getType();
        // Add all properties to views table data. We need an entry for each
        // column of each field, with the first one given special treatment.
        // @todo Introduce concept of the "main" column for a field, rather than
        //   assuming the first one is the main column. See also what the
        //   mapSingleFieldViewsData() method does with $first.
        $first = TRUE;
        foreach ($field_column_mapping as $field_column_name => $schema_field_name) {
            $table_data[$schema_field_name] = $this->mapSingleFieldViewsData($table, $field_name, $field_definition_type, $field_column_name, $field_schema['columns'][$field_column_name]['type'], $first, $field_definition);
            $table_data[$schema_field_name]['entity field'] = $field_name;
            $first = FALSE;
        }
    }
    
    /**
     * Provides the views data for a given data type and schema field.
     *
     * @param string $table
     *   The table of the field to handle.
     * @param string $field_name
     *   The machine name of the field being processed.
     * @param string $field_type
     *   The type of field being handled.
     * @param string $column_name
     *   For fields containing multiple columns, the column name being processed.
     * @param string $column_type
     *   Within the field, the column type being handled.
     * @param bool $first
     *   TRUE if this is the first column within the field.
     * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
     *   The field definition.
     *
     * @return array
     *   The modified views data field definition.
     */
    protected function mapSingleFieldViewsData($table, $field_name, $field_type, $column_name, $column_type, $first, FieldDefinitionInterface $field_definition) {
        $views_field = [];
        // Provide a nicer, less verbose label for the first column within a field.
        // @todo Introduce concept of the "main" column for a field, rather than
        //   assuming the first one is the main column.
        if ($first) {
            $views_field['title'] = $field_definition->getLabel();
        }
        else {
            $views_field['title'] = $field_definition->getLabel() . " ({$column_name})";
        }
        if ($description = $field_definition->getDescription()) {
            $views_field['help'] = $description;
        }
        // Set up the field, sort, argument, and filters, based on
        // the column and/or field data type.
        // @todo Allow field types to customize this.
        // @see https://www.drupal.org/node/2337515
        switch ($field_type) {
            // Special case a few field types.
            case 'timestamp':
            case 'created':
            case 'changed':
                $views_field['field']['id'] = 'field';
                $views_field['argument']['id'] = 'date';
                $views_field['filter']['id'] = 'date';
                $views_field['sort']['id'] = 'date';
                break;
            case 'language':
                $views_field['field']['id'] = 'field';
                $views_field['argument']['id'] = 'language';
                $views_field['filter']['id'] = 'language';
                $views_field['sort']['id'] = 'standard';
                break;
            case 'boolean':
                $views_field['field']['id'] = 'field';
                $views_field['argument']['id'] = 'numeric';
                $views_field['filter']['id'] = 'boolean';
                $views_field['sort']['id'] = 'standard';
                break;
            case 'uri':
                // Let's render URIs as URIs by default, not links.
                $views_field['field']['id'] = 'field';
                $views_field['field']['default_formatter'] = 'string';
                $views_field['argument']['id'] = 'string';
                $views_field['filter']['id'] = 'string';
                $views_field['sort']['id'] = 'standard';
                break;
            case 'text':
            case 'text_with_summary':
                // Treat these three long text fields the same.
                $field_type = 'text_long';
            // Intentional fall-through here to the default processing!
            default:
                // For most fields, the field type is generic enough to just use
                // the column type to determine the filters etc.
                switch ($column_type) {
                    case 'int':
                    case 'integer':
                    case 'smallint':
                    case 'tinyint':
                    case 'mediumint':
                    case 'float':
                    case 'double':
                    case 'decimal':
                        $views_field['field']['id'] = 'field';
                        $views_field['argument']['id'] = 'numeric';
                        $views_field['filter']['id'] = 'numeric';
                        $views_field['sort']['id'] = 'standard';
                        break;
                    case 'char':
                    case 'string':
                    case 'varchar':
                    case 'varchar_ascii':
                    case 'tinytext':
                    case 'text':
                    case 'mediumtext':
                    case 'longtext':
                        $views_field['field']['id'] = 'field';
                        $views_field['argument']['id'] = 'string';
                        $views_field['filter']['id'] = 'string';
                        $views_field['sort']['id'] = 'standard';
                        break;
                    default:
                        $views_field['field']['id'] = 'field';
                        $views_field['argument']['id'] = 'standard';
                        $views_field['filter']['id'] = 'standard';
                        $views_field['sort']['id'] = 'standard';
                }
        }
        // Do post-processing for a few field types.
        $process_method = 'processViewsDataFor' . Container::camelize($field_type);
        if (method_exists($this, $process_method)) {
            $this->{$process_method}($table, $field_definition, $views_field, $column_name);
        }
        return $views_field;
    }
    
    /**
     * Processes the views data for a language field.
     *
     * @param string $table
     *   The table the language field is added to.
     * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
     *   The field definition.
     * @param array $views_field
     *   The views field data.
     * @param string $field_column_name
     *   The field column being processed.
     */
    protected function processViewsDataForLanguage($table, FieldDefinitionInterface $field_definition, array &$views_field, $field_column_name) {
        // Apply special titles for the langcode field.
        if ($field_definition->getName() == $this->entityType
            ->getKey('langcode')) {
            if ($table == $this->entityType
                ->getDataTable() || $table == $this->entityType
                ->getRevisionDataTable()) {
                $views_field['title'] = $this->t('Translation language');
            }
            if ($table == $this->entityType
                ->getBaseTable() || $table == $this->entityType
                ->getRevisionTable()) {
                $views_field['title'] = $this->t('Original language');
            }
        }
    }
    
    /**
     * Processes the views data for an entity reference field.
     *
     * @param string $table
     *   The table the language field is added to.
     * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
     *   The field definition.
     * @param array $views_field
     *   The views field data.
     * @param string $field_column_name
     *   The field column being processed.
     */
    protected function processViewsDataForEntityReference($table, FieldDefinitionInterface $field_definition, array &$views_field, $field_column_name) {
        // @todo Should the actual field handler respect that this just renders a
        //   number?
        // @todo Create an optional entity field handler, that can render the
        //   entity.
        // @see https://www.drupal.org/node/2322949
        if ($entity_type_id = $field_definition->getItemDefinition()
            ->getSetting('target_type')) {
            $entity_type = $this->entityTypeManager
                ->getDefinition($entity_type_id);
            if ($entity_type instanceof ContentEntityType) {
                $views_field['relationship'] = [
                    'base' => $this->getViewsTableForEntityType($entity_type),
                    'base field' => $entity_type->getKey('id'),
                    'label' => $entity_type->getLabel(),
                    'title' => $entity_type->getLabel(),
                    'id' => 'standard',
                ];
                $views_field['field']['id'] = 'field';
                $views_field['argument']['id'] = 'numeric';
                $views_field['filter']['id'] = 'numeric';
                $views_field['sort']['id'] = 'standard';
            }
            else {
                $views_field['field']['id'] = 'field';
                $views_field['argument']['id'] = 'string';
                $views_field['filter']['id'] = 'string';
                $views_field['sort']['id'] = 'standard';
            }
        }
        if ($field_definition->getName() == $this->entityType
            ->getKey('bundle')) {
            $views_field['filter']['id'] = 'bundle';
        }
    }
    
    /**
     * Processes the views data for a text field with formatting.
     *
     * @param string $table
     *   The table the field is added to.
     * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
     *   The field definition.
     * @param array $views_field
     *   The views field data.
     * @param string $field_column_name
     *   The field column being processed.
     */
    protected function processViewsDataForTextLong($table, FieldDefinitionInterface $field_definition, array &$views_field, $field_column_name) {
        // Connect the text field to its formatter.
        if ($field_column_name == 'value') {
            $views_field['field']['format'] = $field_definition->getName() . '__format';
            $views_field['field']['id'] = 'field';
        }
    }
    
    /**
     * Processes the views data for a UUID field.
     *
     * @param string $table
     *   The table the field is added to.
     * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
     *   The field definition.
     * @param array $views_field
     *   The views field data.
     * @param string $field_column_name
     *   The field column being processed.
     */
    protected function processViewsDataForUuid($table, FieldDefinitionInterface $field_definition, array &$views_field, $field_column_name) {
        // It does not make sense for UUID fields to be click sortable.
        $views_field['field']['click sortable'] = FALSE;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getViewsTableForEntityType(EntityTypeInterface $entity_type) {
        return $entity_type->getDataTable() ?: $entity_type->getBaseTable();
    }

}