ViewExecutable.php

<?php

namespace Drupal\views;

use Drupal\Component\Render\FormattableMarkup;
use Drupal\Component\Utility\Html;
use Drupal\Component\Utility\Tags;
use Drupal\Core\Routing\RouteProviderInterface;
use Drupal\Core\Session\AccountInterface;
use Drupal\views\Plugin\views\display\DisplayRouterInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Exception\RouteNotFoundException;

/**
 * Represents a view as a whole.
 *
 * An object to contain all of the data to generate a view, plus the member
 * functions to build the view query, execute the query and render the output.
 *
 * This class does not implement the Serializable interface since problems
 * occurred when using the serialize method.
 *
 * @see https://www.drupal.org/node/2849674
 * @see https://bugs.php.net/bug.php?id=66052
 */
class ViewExecutable {
    
    /**
     * The config entity in which the view is stored.
     *
     * @var \Drupal\views\Entity\View
     */
    public $storage;
    
    /**
     * Whether or not the view has been built.
     *
     * @todo Group with other static properties.
     *
     * @var bool
     */
    public $built = FALSE;
    
    /**
     * Whether the view has been executed/query has been run.
     *
     * @todo Group with other static properties.
     *
     * @var bool
     */
    public $executed = FALSE;
    
    /**
     * Any arguments that have been passed into the view.
     *
     * @var array
     */
    public $args = [];
    
    /**
     * An array of build info.
     *
     * @var array
     */
    public $build_info = [];
    
    /**
     * Whether this view uses AJAX.
     *
     * @var bool
     */
    protected $ajaxEnabled = FALSE;
    
    /**
     * Where the results of a query will go.
     *
     * The array must use a numeric index starting at 0.
     *
     * @var \Drupal\views\ResultRow[]
     */
    public $result = [];
    // May be used to override the current pager info.
    
    /**
     * The current page. If the view uses pagination.
     *
     * @var int
     */
    protected $current_page = NULL;
    
    /**
     * The number of items per page.
     *
     * @var int
     */
    protected $items_per_page = NULL;
    
    /**
     * The pager offset.
     *
     * @var int
     */
    protected $offset = NULL;
    
    /**
     * The total number of rows returned from the query.
     *
     * @var int
     */
    public $total_rows = NULL;
    
    /**
     * Attachments to place before the view.
     *
     * @var array
     */
    public $attachment_before = [];
    
    /**
     * Attachments to place after the view.
     *
     * @var array
     */
    public $attachment_after = [];
    
    /**
     * Feed icons attached to the view.
     *
     * @var array
     */
    public $feedIcons = [];
    // Exposed widget input
    
    /**
     * All the form data from $form_state->getValues().
     *
     * @var array
     */
    public $exposed_data = [];
    
    /**
     * An array of input values from exposed forms.
     *
     * @var array
     */
    protected $exposed_input = [];
    
    /**
     * Exposed widget input directly from the $form_state->getValues().
     *
     * @var array
     */
    public $exposed_raw_input = [];
    
    /**
     * Used to store views that were previously running if we recurse.
     *
     * @var \Drupal\views\ViewExecutable[]
     */
    public $old_view = [];
    
    /**
     * To avoid recursion in views embedded into areas.
     *
     * @var \Drupal\views\ViewExecutable[]
     */
    public $parent_views = [];
    
    /**
     * Whether this view is an attachment to another view.
     *
     * @var bool
     */
    public $is_attachment = NULL;
    
    /**
     * Identifier of the current display.
     *
     * @var string
     */
    public $current_display;
    
    /**
     * Where the $query object will reside.
     *
     * @var \Drupal\views\Plugin\views\query\QueryPluginBase
     */
    public $query = NULL;
    
    /**
     * The used pager plugin used by the current executed view.
     *
     * @var \Drupal\views\Plugin\views\pager\PagerPluginBase
     */
    public $pager = NULL;
    
    /**
     * The current used display plugin.
     *
     * @var \Drupal\views\Plugin\views\display\DisplayPluginBase
     */
    public $display_handler;
    
    /**
     * The list of used displays of the view.
     *
     * An array containing Drupal\views\Plugin\views\display\DisplayPluginBase
     * objects.
     *
     * @var \Drupal\views\DisplayPluginCollection
     */
    public $displayHandlers;
    
    /**
     * The current used style plugin.
     *
     * @var \Drupal\views\Plugin\views\style\StylePluginBase
     */
    public $style_plugin;
    
    /**
     * The current used row plugin, if the style plugin supports row plugins.
     *
     * @var \Drupal\views\Plugin\views\row\RowPluginBase
     */
    public $rowPlugin;
    
    /**
     * Stores the current active row while rendering.
     *
     * @var int
     */
    public $row_index;
    
    /**
     * Allow to override the \Drupal\Core\Url of the current view.
     *
     * @var \Drupal\Core\Url
     */
    public $override_url;
    
    /**
     * Allow to override the path used for generated urls.
     *
     * @var string
     */
    public $override_path = NULL;
    
    /**
     * Allow to override the used database which is used for this query.
     *
     * @var bool
     */
    public $base_database = NULL;
    // Handlers which are active on this view.
    
    /**
     * Stores the field handlers which are initialized on this view.
     *
     * @var \Drupal\views\Plugin\views\field\FieldPluginBase[]
     */
    public $field;
    
    /**
     * Stores the argument handlers which are initialized on this view.
     *
     * @var \Drupal\views\Plugin\views\argument\ArgumentPluginBase[]
     */
    public $argument;
    
    /**
     * Stores the sort handlers which are initialized on this view.
     *
     * @var \Drupal\views\Plugin\views\sort\SortPluginBase[]
     */
    public $sort;
    
    /**
     * Stores the filter handlers which are initialized on this view.
     *
     * @var \Drupal\views\Plugin\views\filter\FilterPluginBase[]
     */
    public $filter;
    
    /**
     * Stores the relationship handlers which are initialized on this view.
     *
     * @var \Drupal\views\Plugin\views\relationship\RelationshipPluginBase[]
     */
    public $relationship;
    
    /**
     * Stores the area handlers for the header which are initialized on this view.
     *
     * @var \Drupal\views\Plugin\views\area\AreaPluginBase[]
     */
    public $header;
    
    /**
     * Stores the area handlers for the footer which are initialized on this view.
     *
     * @var \Drupal\views\Plugin\views\area\AreaPluginBase[]
     */
    public $footer;
    
    /**
     * Stores the area handlers for the empty text which are initialized on this view.
     *
     * An array containing Drupal\views\Plugin\views\area\AreaPluginBase objects.
     *
     * @var \Drupal\views\Plugin\views\area\AreaPluginBase[]
     */
    public $empty;
    
    /**
     * Stores the current response object.
     *
     * @var \Symfony\Component\HttpFoundation\Response
     */
    protected $response = NULL;
    
    /**
     * Stores the current request object.
     *
     * @var \Symfony\Component\HttpFoundation\Request
     */
    protected $request;
    
    /**
     * Does this view already have loaded its handlers.
     *
     * @todo Group with other static properties.
     *
     * @var bool
     */
    public $inited;
    
    /**
     * The render array for the exposed form.
     *
     * In cases that the exposed form is rendered as a block this will be an
     * empty array.
     *
     * @var array
     */
    public $exposed_widgets;
    
    /**
     * If this view has been previewed.
     *
     * @var bool
     */
    public $preview;
    
    /**
     * Force the query to calculate the total number of results.
     *
     * @todo Move to the query.
     *
     * @var bool
     */
    public $get_total_rows;
    
    /**
     * Indicates if the sorts have been built.
     *
     * @todo Group with other static properties.
     *
     * @var bool
     */
    public $build_sort;
    
    /**
     * Stores the many-to-one tables for performance.
     *
     * @var array
     */
    public $many_to_one_tables;
    
    /**
     * A unique identifier which allows to update multiple views output via js.
     *
     * @var string
     */
    public $dom_id;
    
    /**
     * A render array container to store render related information.
     *
     * For example you can alter the array and attach some asset library or JS
     * settings via the #attached key. This is the required way to add custom
     * CSS or JS.
     *
     * @var array
     *
     * @see \Drupal\Core\Render\AttachmentsResponseProcessorInterface::processAttachments()
     */
    public $element = [
        '#attached' => [
            'library' => [
                'views/views.module',
            ],
            'drupalSettings' => [],
        ],
        '#cache' => [],
    ];
    
    /**
     * The current user.
     *
     * @var \Drupal\Core\Session\AccountInterface
     */
    protected $user;
    
    /**
     * Should the admin links be shown on the rendered view.
     *
     * @var bool
     */
    protected $showAdminLinks;
    
    /**
     * The views data.
     *
     * @var \Drupal\views\ViewsData
     */
    protected $viewsData;
    
    /**
     * The route provider.
     *
     * @var \Drupal\Core\Routing\RouteProviderInterface
     */
    protected $routeProvider;
    
    /**
     * The entity type of the base table, if available.
     *
     * @var \Drupal\Core\Entity\EntityTypeInterface|false
     */
    protected $baseEntityType;
    
    /**
     * Holds all necessary data for proper unserialization.
     *
     * @var array
     */
    protected $serializationData;
    
    /**
     * Constructs a new ViewExecutable object.
     *
     * @param \Drupal\views\ViewEntityInterface $storage
     *   The view config entity the actual information is stored on.
     * @param \Drupal\Core\Session\AccountInterface $user
     *   The current user.
     * @param \Drupal\views\ViewsData $views_data
     *   The views data.
     * @param \Drupal\Core\Routing\RouteProviderInterface $route_provider
     *   The route provider.
     */
    public function __construct(ViewEntityInterface $storage, AccountInterface $user, ViewsData $views_data, RouteProviderInterface $route_provider) {
        // Reference the storage and the executable to each other.
        $this->storage = $storage;
        $this->storage
            ->set('executable', $this);
        $this->user = $user;
        $this->viewsData = $views_data;
        $this->routeProvider = $route_provider;
    }
    
    /**
     * Returns the identifier.
     *
     * @return string|null
     *   The entity identifier, or NULL if the object does not yet have an
     *   identifier.
     */
    public function id() {
        return $this->storage
            ->id();
    }
    
    /**
     * Saves the view.
     */
    public function save() {
        $this->storage
            ->save();
    }
    
    /**
     * Sets the arguments for the view.
     *
     * @param array $args
     *   The arguments passed to the view.
     */
    public function setArguments(array $args) {
        // The array keys of the arguments will be incorrect if set by
        // views_embed_view() or \Drupal\views\ViewExecutable:preview().
        $this->args = array_values($args);
    }
    
    /**
     * Expands the list of used cache contexts for the view.
     *
     * @param string $cache_context
     *   The additional cache context.
     *
     * @return $this
     */
    public function addCacheContext($cache_context) {
        $this->element['#cache']['contexts'][] = $cache_context;
        return $this;
    }
    
    /**
     * Sets the current page for the pager.
     *
     * @param int $page
     *   The current page.
     */
    public function setCurrentPage($page) {
        $this->current_page = $page;
        // Calls like ::unserialize() might call this method without a proper $page.
        // Also check whether the element is pre rendered. At that point, the cache
        // keys cannot longer be manipulated.
        if ($page !== NULL && empty($this->element['#pre_rendered'])) {
            $this->element['#cache']['keys'][] = 'page:' . $page;
        }
        // If the pager is already initialized, pass it through to the pager.
        if (!empty($this->pager)) {
            return $this->pager
                ->setCurrentPage($page);
        }
    }
    
    /**
     * Gets the current page from the pager.
     *
     * @return int
     *   The current page.
     */
    public function getCurrentPage() {
        // If the pager is already initialized, pass it through to the pager.
        if (!empty($this->pager)) {
            return $this->pager
                ->getCurrentPage();
        }
        if (isset($this->current_page)) {
            return $this->current_page;
        }
    }
    
    /**
     * Gets the items per page from the pager.
     *
     * @return int
     *   The items per page.
     */
    public function getItemsPerPage() {
        // If the pager is already initialized, pass it through to the pager.
        if (!empty($this->pager)) {
            return $this->pager
                ->getItemsPerPage();
        }
        if (isset($this->items_per_page)) {
            return $this->items_per_page;
        }
    }
    
    /**
     * Sets the items per page on the pager.
     *
     * @param int $items_per_page
     *   The items per page.
     */
    public function setItemsPerPage($items_per_page) {
        // Check whether the element is pre rendered. At that point, the cache keys
        // cannot longer be manipulated.
        if (empty($this->element['#pre_rendered'])) {
            $this->element['#cache']['keys'][] = 'items_per_page:' . $items_per_page;
        }
        $this->items_per_page = $items_per_page;
        // If the pager is already initialized, pass it through to the pager.
        if (!empty($this->pager)) {
            $this->pager
                ->setItemsPerPage($items_per_page);
        }
    }
    
    /**
     * Gets the pager offset from the pager.
     *
     * @return int
     *   The pager offset.
     */
    public function getOffset() {
        // If the pager is already initialized, pass it through to the pager.
        if (!empty($this->pager)) {
            return $this->pager
                ->getOffset();
        }
        if (isset($this->offset)) {
            return $this->offset;
        }
    }
    
    /**
     * Sets the offset on the pager.
     *
     * @param int $offset
     *   The pager offset.
     */
    public function setOffset($offset) {
        // Check whether the element is pre rendered. At that point, the cache keys
        // cannot longer be manipulated.
        if (empty($this->element['#pre_rendered'])) {
            $this->element['#cache']['keys'][] = 'offset:' . $offset;
        }
        $this->offset = $offset;
        // If the pager is already initialized, pass it through to the pager.
        if (!empty($this->pager)) {
            $this->pager
                ->setOffset($offset);
        }
    }
    
    /**
     * Determines if the view uses a pager.
     *
     * @return bool
     *   TRUE if the view uses a pager, FALSE otherwise.
     */
    public function usePager() {
        if (!empty($this->pager)) {
            return $this->pager
                ->usePager();
        }
    }
    
    /**
     * Sets whether or not AJAX should be used.
     *
     * If AJAX is used, paging, table sorting, and exposed filters will be fetched
     * via an AJAX call rather than a page refresh.
     *
     * @param bool $ajax_enabled
     *   TRUE if AJAX should be used, FALSE otherwise.
     */
    public function setAjaxEnabled($ajax_enabled) {
        $this->ajaxEnabled = (bool) $ajax_enabled;
    }
    
    /**
     * Determines whether or not AJAX should be used.
     *
     * @return bool
     *   TRUE if AJAX is enabled, FALSE otherwise.
     */
    public function ajaxEnabled() {
        return $this->ajaxEnabled;
    }
    
    /**
     * Sets the exposed filters input to an array.
     *
     * @param string[] $filters
     *   The values taken from the view's exposed filters and sorts.
     */
    public function setExposedInput($filters) {
        $this->exposed_input = $filters;
    }
    
    /**
     * Figures out what the exposed input for this view is.
     *
     * They will be taken from \Drupal::request()->query or from
     * something previously set on the view.
     *
     * @return string[]
     *   An array containing the exposed input values keyed by the filter and sort
     *   name.
     *
     * @see self::setExposedInput()
     */
    public function getExposedInput() {
        // Fill our input either from \Drupal::request()->query or from something
        // previously set on the view.
        if (empty($this->exposed_input)) {
            // Ensure that we can call the method at any point in time.
            $this->initDisplay();
            $this->exposed_input = \Drupal::request()->query
                ->all();
            // unset items that are definitely not our input:
            foreach ([
                'page',
                'q',
            ] as $key) {
                if (isset($this->exposed_input[$key])) {
                    unset($this->exposed_input[$key]);
                }
            }
            // If we have no input at all, check for remembered input via session.
            if (empty($this->exposed_input) && $this->request
                ->hasSession()) {
                $session = \Drupal::request()->getSession();
                // If filters are not overridden, store the 'remember' settings on the
                // default display. If they are, store them on this display. This way,
                // multiple displays in the same view can share the same filters and
                // remember settings.
                $display_id = $this->display_handler
                    ->isDefaulted('filters') ? 'default' : $this->current_display;
                if (!empty($session->get('views')[$this->storage
                    ->id()][$display_id])) {
                    $this->exposed_input = $session->get('views')[$this->storage
                        ->id()][$display_id];
                }
            }
        }
        return $this->exposed_input;
    }
    
    /**
     * Sets the display for this view and initializes the display handler.
     *
     * @return true
     *   Always returns TRUE.
     */
    public function initDisplay() {
        if (isset($this->current_display)) {
            return TRUE;
        }
        // Initialize the display cache array.
        $this->displayHandlers = new DisplayPluginCollection($this, Views::pluginManager('display'));
        $this->current_display = 'default';
        $this->display_handler = $this->displayHandlers
            ->get('default');
        return TRUE;
    }
    
    /**
     * Gets the first display that is accessible to the user.
     *
     * @param array|string $displays
     *   Either a single display id or an array of display ids.
     *
     * @return string
     *   The first accessible display id, at least default.
     */
    public function chooseDisplay($displays) {
        if (!is_array($displays)) {
            return $displays;
        }
        $this->initDisplay();
        foreach ($displays as $display_id) {
            if ($this->displayHandlers
                ->get($display_id)
                ->access($this->user)) {
                return $display_id;
            }
        }
        return 'default';
    }
    
    /**
     * Gets the current display plugin.
     *
     * @return \Drupal\views\Plugin\views\display\DisplayPluginBase
     *   The current display plugin.
     */
    public function getDisplay() {
        if (!isset($this->display_handler)) {
            $this->initDisplay();
        }
        return $this->display_handler;
    }
    
    /**
     * Sets the current display.
     *
     * @param string $display_id
     *   The ID of the display to mark as current.
     *
     * @return bool
     *   TRUE if the display was correctly set, FALSE otherwise.
     */
    public function setDisplay($display_id = NULL) {
        // If we have not already initialized the display, do so.
        if (!isset($this->current_display)) {
            // This will set the default display and instantiate the default display
            // plugin.
            $this->initDisplay();
        }
        // If no display ID is passed, we either have initialized the default or
        // already have a display set.
        if (!isset($display_id)) {
            return TRUE;
        }
        $display_id = $this->chooseDisplay($display_id);
        // Ensure the requested display exists.
        if (!$this->displayHandlers
            ->has($display_id)) {
            trigger_error(new FormattableMarkup('setDisplay() called with invalid display ID "@display".', [
                '@display' => $display_id,
            ]), E_USER_WARNING);
            return FALSE;
        }
        // Reset if the display has changed. It could be called multiple times for
        // the same display, especially in the UI.
        if ($this->current_display != $display_id) {
            // Set the current display.
            $this->current_display = $display_id;
            // Reset the style and row plugins.
            $this->style_plugin = NULL;
            $this->plugin_name = NULL;
            $this->rowPlugin = NULL;
        }
        if ($display = $this->displayHandlers
            ->get($display_id)) {
            // Set a shortcut.
            $this->display_handler = $display;
            return TRUE;
        }
        return FALSE;
    }
    
    /**
     * Creates a new display and a display handler instance for it.
     *
     * @param string $plugin_id
     *   (optional) The plugin type from the Views plugin annotation. Defaults to
     *   'page'.
     * @param string $title
     *   (optional) The title of the display. Defaults to NULL.
     * @param string $id
     *   (optional) The ID to use, e.g., 'default', 'page_1', 'block_2'. Defaults
     *   to NULL.
     *
     * @return \Drupal\views\Plugin\views\display\DisplayPluginBase
     *   A new display plugin instance if executable is set, the new display ID
     *   otherwise.
     */
    public function newDisplay($plugin_id = 'page', $title = NULL, $id = NULL) {
        $this->initDisplay();
        $id = $this->storage
            ->addDisplay($plugin_id, $title, $id);
        $this->displayHandlers
            ->addInstanceId($id);
        $display = $this->displayHandlers
            ->get($id);
        $display->newDisplay();
        return $display;
    }
    
    /**
     * Gets the current style plugin.
     *
     * @return \Drupal\views\Plugin\views\style\StylePluginBase
     *   The current style plugin.
     */
    public function getStyle() {
        if (!isset($this->style_plugin)) {
            $this->initStyle();
        }
        return $this->style_plugin;
    }
    
    /**
     * Finds and initializes the style plugin.
     *
     * Note that arguments may have changed which style plugin we use, so
     * check the view object first, then ask the display handler.
     *
     * @return bool
     *   TRUE if the style plugin was or could be initialized, FALSE otherwise.
     */
    public function initStyle() {
        if (isset($this->style_plugin)) {
            return TRUE;
        }
        $this->style_plugin = $this->display_handler
            ->getPlugin('style');
        if (empty($this->style_plugin)) {
            return FALSE;
        }
        return TRUE;
    }
    
    /**
     * Acquires and attaches all of the handlers.
     */
    public function initHandlers() {
        $this->initDisplay();
        if (empty($this->inited)) {
            foreach ($this::getHandlerTypes() as $key => $info) {
                $this->_initHandler($key, $info);
            }
            $this->inited = TRUE;
        }
    }
    
    /**
     * Gets the current pager plugin.
     *
     * @return \Drupal\views\Plugin\views\pager\PagerPluginBase
     *   The current pager plugin.
     */
    public function getPager() {
        if (!isset($this->pager)) {
            $this->initPager();
        }
        return $this->pager;
    }
    
    /**
     * Initializes the pager.
     *
     * Like style initialization, pager initialization is held until late to allow
     * for overrides.
     */
    public function initPager() {
        if (!isset($this->pager)) {
            $this->pager = $this->display_handler
                ->getPlugin('pager');
            if ($this->usePager()) {
                $this->pager
                    ->setCurrentPage($this->current_page);
            }
            // These overrides may have been set earlier via $view->set_*
            // functions.
            if (isset($this->items_per_page)) {
                $this->pager
                    ->setItemsPerPage($this->items_per_page);
            }
            if (isset($this->offset)) {
                $this->pager
                    ->setOffset($this->offset);
            }
        }
    }
    
    /**
     * Renders the pager, if necessary.
     *
     * @param string[] $exposed_input
     *   The input values from the exposed forms and sorts of the view.
     *
     * @return array|string
     *   The render array of the pager if it's set, blank string otherwise.
     */
    public function renderPager($exposed_input) {
        if ($this->usePager()) {
            return $this->pager
                ->render($exposed_input);
        }
        return '';
    }
    
    /**
     * Creates a list of base tables to be used by the view.
     *
     * This is used primarily for the UI. The display must be already initialized.
     *
     * @return array
     *   An array of base tables to be used by the view.
     */
    public function getBaseTables() {
        $base_tables = [
            $this->storage
                ->get('base_table') => TRUE,
            '#global' => TRUE,
        ];
        foreach ($this->display_handler
            ->getHandlers('relationship') as $handler) {
            $base_tables[$handler->definition['base']] = TRUE;
        }
        return $base_tables;
    }
    
    /**
     * Returns the entity type of the base table, if available.
     *
     * @return \Drupal\Core\Entity\EntityType|false
     *   The entity type of the base table, or FALSE if none exists.
     */
    public function getBaseEntityType() {
        if (!isset($this->baseEntityType)) {
            $view_base_table = $this->storage
                ->get('base_table');
            $views_data = $this->viewsData
                ->get($view_base_table);
            if (!empty($views_data['table']['entity type'])) {
                $entity_type_id = $views_data['table']['entity type'];
                $this->baseEntityType = \Drupal::entityTypeManager()->getDefinition($entity_type_id);
            }
            else {
                $this->baseEntityType = FALSE;
            }
        }
        return $this->baseEntityType;
    }
    
    /**
     * Runs the preQuery() on all active handlers.
     */
    protected function _preQuery() {
        foreach ($this::getHandlerTypes() as $key => $info) {
            $handlers =& $this->{$key};
            $position = 0;
            foreach ($handlers as $id => $handler) {
                $handlers[$id]->position = $position;
                $handlers[$id]->preQuery();
                $position++;
            }
        }
    }
    
    /**
     * Runs the postExecute() on all active handlers.
     */
    protected function _postExecute() {
        foreach ($this::getHandlerTypes() as $key => $info) {
            $handlers =& $this->{$key};
            foreach ($handlers as $id => $handler) {
                $handlers[$id]->postExecute($this->result);
            }
        }
    }
    
    /**
     * Attaches the views handler for the specific type.
     *
     * @param string $key
     *   One of 'argument', 'field', 'sort', 'filter', 'relationship'.
     * @param array $info
     *   An array of views handler types use in the view with additional
     *   information about them.
     */
    protected function _initHandler($key, $info) {
        // Load the requested items from the display onto the object.
        $this->{$key} =& $this->display_handler
            ->getHandlers($key);
        // This reference deals with difficult PHP indirection.
        $handlers =& $this->{$key};
        // Run through and test for accessibility.
        foreach ($handlers as $id => $handler) {
            if (!$handler->access($this->user)) {
                unset($handlers[$id]);
            }
        }
    }
    
    /**
     * Builds all the arguments.
     *
     * @return bool
     *   TRUE if the arguments were built successfully, FALSE otherwise.
     */
    protected function _buildArguments() {
        // Initially, we want to build sorts and fields. This can change, though,
        // if we get a summary view.
        if (empty($this->argument)) {
            return TRUE;
        }
        // build arguments.
        $position = -1;
        $substitutions = [];
        $status = TRUE;
        // Get the title.
        $title = $this->display_handler
            ->getOption('title');
        // Iterate through each argument and process.
        foreach ($this->argument as $id => $arg) {
            $position++;
            $argument = $this->argument[$id];
            if ($argument->broken()) {
                continue;
            }
            $argument->setRelationship();
            $arg = $this->args[$position] ?? NULL;
            $argument->position = $position;
            if (isset($arg) || $argument->hasDefaultArgument()) {
                if (!isset($arg)) {
                    $arg = $argument->getDefaultArgument();
                    // make sure default args get put back.
                    if (isset($arg)) {
                        $this->args[$position] = $arg;
                    }
                    // remember that this argument was computed, not passed on the URL.
                    $argument->is_default = TRUE;
                }
                // Set the argument, which ensures that the argument is valid and
                // possibly transforms the value.
                if (!$argument->setArgument($arg)) {
                    $status = $argument->validateFail($arg);
                    break;
                }
                if ($argument->isException()) {
                    $arg_title = $argument->exceptionTitle();
                }
                else {
                    $arg_title = $argument->getTitle();
                    $argument->query($this->display_handler
                        ->useGroupBy());
                }
                // Add this argument's substitution.
                $substitutions["{{ arguments.{$id} }}"] = $arg_title;
                // Since argument validator plugins can potentially transform the value,
                // use whatever value the argument handler now has, not the raw value.
                $substitutions["{{ raw_arguments.{$id} }}"] = strip_tags(Html::decodeEntities($argument->getValue()));
                // Test to see if we should use this argument's title
                if (!empty($argument->options['title_enable']) && !empty($argument->options['title'])) {
                    $title = $argument->options['title'];
                }
            }
            else {
                // determine default condition and handle.
                $status = $argument->defaultAction();
                break;
            }
            // Be safe with references and loops:
            unset($argument);
        }
        // set the title in the build info.
        if (!empty($title)) {
            $this->build_info['title'] = $title;
        }
        // Store the arguments for later use.
        $this->build_info['substitutions'] = $substitutions;
        return $status;
    }
    
    /**
     * Gets the current query plugin.
     *
     * @return \Drupal\views\Plugin\views\query\QueryPluginBase
     *   The current query plugin.
     */
    public function getQuery() {
        if (!isset($this->query)) {
            $this->initQuery();
        }
        return $this->query;
    }
    
    /**
     * Initializes the query object for the view.
     *
     * @return true
     *   Always returns TRUE.
     */
    public function initQuery() {
        if (!empty($this->query)) {
            $class = get_class($this->query);
            if ($class && $class != 'stdClass') {
                // return if query is already initialized.
                return TRUE;
            }
        }
        // Create and initialize the query object.
        $views_data = Views::viewsData()->get($this->storage
            ->get('base_table'));
        $this->storage
            ->set('base_field', !empty($views_data['table']['base']['field']) ? $views_data['table']['base']['field'] : '');
        if (!empty($views_data['table']['base']['database'])) {
            $this->base_database = $views_data['table']['base']['database'];
        }
        $this->query = $this->display_handler
            ->getPlugin('query');
        return TRUE;
    }
    
    /**
     * Builds the query for the view.
     *
     * @param string $display_id
     *   The display ID of the view.
     *
     * @return bool|null
     *   TRUE if the view build process was successful, FALSE if setting the
     *   display fails or NULL if the view has been built already.
     */
    public function build($display_id = NULL) {
        if (!empty($this->built)) {
            return;
        }
        if (empty($this->current_display) || $display_id) {
            if (!$this->setDisplay($display_id)) {
                return FALSE;
            }
        }
        // Let modules modify the view just prior to building it.
        $module_handler = \Drupal::moduleHandler();
        $module_handler->invokeAll('views_pre_build', [
            $this,
        ]);
        // Attempt to load from cache.
        // @todo Load a build_info from cache.
        $start = microtime(TRUE);
        // If that fails, let's build!
        $this->build_info = [
            'query' => '',
            'count_query' => '',
            'query_args' => [],
        ];
        $this->initQuery();
        // Call a module hook and see if it wants to present us with a
        // pre-built query or instruct us not to build the query for
        // some reason.
        // @todo: Implement this. Use the same mechanism Panels uses.
        // Run through our handlers and ensure they have necessary information.
        $this->initHandlers();
        // Let the handlers interact with each other if they really want.
        $this->_preQuery();
        if ($this->display_handler
            ->usesExposed()) {
            
            /** @var \Drupal\views\Plugin\views\exposed_form\ExposedFormPluginInterface $exposed_form */
            $exposed_form = $this->display_handler
                ->getPlugin('exposed_form');
            $this->exposed_widgets = $exposed_form->renderExposedForm();
            if (!empty($this->build_info['abort'])) {
                $this->built = TRUE;
                // Don't execute the query, $form_state, but rendering will still be executed to display the empty text.
                $this->executed = TRUE;
                return empty($this->build_info['fail']);
            }
        }
        // Build all the relationships first thing.
        $this->_build('relationship');
        // Set the filtering groups.
        if (!empty($this->filter)) {
            $filter_groups = $this->display_handler
                ->getOption('filter_groups');
            if ($filter_groups) {
                $this->query
                    ->setGroupOperator($filter_groups['operator']);
                foreach ($filter_groups['groups'] as $id => $operator) {
                    $this->query
                        ->setWhereGroup($operator, $id);
                }
            }
        }
        // Build all the filters.
        $this->_build('filter');
        $this->build_sort = TRUE;
        // Arguments can, in fact, cause this whole thing to abort.
        if (!$this->_buildArguments()) {
            $this->build_time = microtime(TRUE) - $start;
            $this->attachDisplays();
            return $this->built;
        }
        // Initialize the style; arguments may have changed which style we use,
        // so waiting as long as possible is important. But we need to know
        // about the style when we go to build fields.
        if (!$this->initStyle()) {
            $this->build_info['fail'] = TRUE;
            return FALSE;
        }
        if ($this->style_plugin
            ->usesFields()) {
            $this->_build('field');
        }
        // Build our sort criteria if we were instructed to do so.
        if (!empty($this->build_sort)) {
            // Allow the style handler to deal with sorting.
            if ($this->style_plugin
                ->buildSort()) {
                $this->_build('sort');
            }
            // allow the plugin to build second sorts as well.
            $this->style_plugin
                ->buildSortPost();
        }
        // Allow area handlers to affect the query.
        $this->_build('header');
        $this->_build('footer');
        $this->_build('empty');
        // Allow display handler to affect the query:
        $this->display_handler
            ->query($this->display_handler
            ->useGroupBy());
        // Allow style handler to affect the query:
        $this->style_plugin
            ->query($this->display_handler
            ->useGroupBy());
        // Allow exposed form to affect the query:
        if (isset($exposed_form)) {
            $exposed_form->query();
        }
        if (\Drupal::config('views.settings')->get('sql_signature')) {
            $this->query
                ->addSignature($this);
        }
        // Let modules modify the query just prior to finalizing it.
        $this->query
            ->alter($this);
        // Only build the query if we weren't interrupted.
        if (empty($this->built)) {
            // Build the necessary info to execute the query.
            $this->query
                ->build($this);
        }
        $this->built = TRUE;
        $this->build_time = microtime(TRUE) - $start;
        // Attach displays
        $this->attachDisplays();
        // Let modules modify the view just after building it.
        $module_handler->invokeAll('views_post_build', [
            $this,
        ]);
        return TRUE;
    }
    
    /**
     * Builds an individual set of handlers.
     *
     * This is an internal method.
     *
     * @todo Some filter needs this function, even it is internal.
     *
     * @param string $key
     *   The type of handlers (filter etc.) which should be iterated over to build
     *   the relationship and query information.
     */
    public function _build($key) {
        $handlers =& $this->{$key};
        foreach ($handlers as $id => $data) {
            if (!empty($handlers[$id]) && is_object($handlers[$id])) {
                $multiple_exposed_input = [
                    0 => NULL,
                ];
                if ($handlers[$id]->multipleExposedInput()) {
                    $multiple_exposed_input = $handlers[$id]->groupMultipleExposedInput($this->exposed_data);
                }
                foreach ($multiple_exposed_input as $group_id) {
                    // Give this handler access to the exposed filter input.
                    if (!empty($this->exposed_data)) {
                        if ($handlers[$id]->isAGroup()) {
                            $converted = $handlers[$id]->convertExposedInput($this->exposed_data, $group_id);
                            $handlers[$id]->storeGroupInput($this->exposed_data, $converted);
                            if (!$converted) {
                                continue;
                            }
                        }
                        $rc = $handlers[$id]->acceptExposedInput($this->exposed_data);
                        $handlers[$id]->storeExposedInput($this->exposed_data, $rc);
                        if (!$rc) {
                            continue;
                        }
                    }
                    $handlers[$id]->setRelationship();
                    $handlers[$id]->query($this->display_handler
                        ->useGroupBy());
                }
            }
        }
    }
    
    /**
     * Executes the view's query.
     *
     * @param string $display_id
     *   The machine name of the display, which should be executed.
     *
     * @return bool
     *   TRUE if the view execution was successful, FALSE otherwise. For example,
     *   an argument could stop the process.
     */
    public function execute($display_id = NULL) {
        if (empty($this->built)) {
            if (!$this->build($display_id)) {
                return FALSE;
            }
        }
        if (!empty($this->executed)) {
            return TRUE;
        }
        // Don't allow to use deactivated displays, but display them on the live preview.
        if (!$this->display_handler
            ->isEnabled() && empty($this->live_preview)) {
            $this->build_info['fail'] = TRUE;
            return FALSE;
        }
        // Let modules modify the view just prior to executing it.
        $module_handler = \Drupal::moduleHandler();
        $module_handler->invokeAll('views_pre_execute', [
            $this,
        ]);
        // Check for already-cached results.
        
        /** @var \Drupal\views\Plugin\views\cache\CachePluginBase $cache */
        if (!empty($this->live_preview)) {
            $cache = Views::pluginManager('cache')->createInstance('none');
        }
        else {
            $cache = $this->display_handler
                ->getPlugin('cache');
        }
        if ($cache->cacheGet('results')) {
            if ($this->usePager()) {
                $this->pager->total_items = $this->total_rows;
                $this->pager
                    ->updatePageInfo();
            }
        }
        else {
            $this->query
                ->execute($this);
            // Enforce the array key rule as documented in
            // views_plugin_query::execute().
            $this->result = array_values($this->result);
            $this->_postExecute();
            $cache->cacheSet('results');
        }
        // Let modules modify the view just after executing it.
        $module_handler->invokeAll('views_post_execute', [
            $this,
        ]);
        return $this->executed = TRUE;
    }
    
    /**
     * Renders this view for a certain display.
     *
     * Note: You should better use just the preview function if you want to
     * render a view.
     *
     * @param string $display_id
     *   The machine name of the display, which should be rendered.
     *
     * @return array|null
     *   A renderable array containing the view output or NULL if the build
     *   process failed.
     */
    public function render($display_id = NULL) {
        $this->execute($display_id);
        // Check to see if the build failed.
        if (!empty($this->build_info['fail'])) {
            return;
        }
        if (!empty($this->build_info['denied'])) {
            return;
        }
        
        /** @var \Drupal\views\Plugin\views\exposed_form\ExposedFormPluginInterface $exposed_form */
        $exposed_form = $this->display_handler
            ->getPlugin('exposed_form');
        $exposed_form->preRender($this->result);
        $module_handler = \Drupal::moduleHandler();
        // @todo In the long run, it would be great to execute a view without
        //   the theme system at all. See https://www.drupal.org/node/2322623.
        $active_theme = \Drupal::theme()->getActiveTheme();
        $themes = array_keys($active_theme->getBaseThemeExtensions());
        $themes[] = $active_theme->getName();
        // Check for already-cached output.
        
        /** @var \Drupal\views\Plugin\views\cache\CachePluginBase $cache */
        if (!empty($this->live_preview)) {
            $cache = Views::pluginManager('cache')->createInstance('none');
        }
        else {
            $cache = $this->display_handler
                ->getPlugin('cache');
        }
        // Run preRender for the pager as it might change the result.
        if (!empty($this->pager)) {
            $this->pager
                ->preRender($this->result);
        }
        // Initialize the style plugin.
        $this->initStyle();
        if (!isset($this->response)) {
            // Set the response so other parts can alter it.
            $this->response = new Response('', 200);
        }
        // Give field handlers the opportunity to perform additional queries
        // using the entire resultset prior to rendering.
        if ($this->style_plugin
            ->usesFields()) {
            foreach ($this->field as $id => $handler) {
                if (!empty($this->field[$id])) {
                    $this->field[$id]
                        ->preRender($this->result);
                }
            }
        }
        $this->style_plugin
            ->preRender($this->result);
        // Let each area handler have access to the result set.
        $areas = [
            'header',
            'footer',
        ];
        // Only call preRender() on the empty handlers if the result is empty.
        if (empty($this->result)) {
            $areas[] = 'empty';
        }
        foreach ($areas as $area) {
            foreach ($this->{$area} as $handler) {
                $handler->preRender($this->result);
            }
        }
        // Let modules modify the view just prior to rendering it.
        $module_handler->invokeAll('views_pre_render', [
            $this,
        ]);
        // Let the themes play too, because prerender is a very themey thing.
        foreach ($themes as $theme_name) {
            $function = $theme_name . '_views_pre_render';
            if (function_exists($function)) {
                $function($this);
            }
        }
        $this->display_handler->output = $this->display_handler
            ->render();
        $exposed_form->postRender($this->display_handler->output);
        $cache->postRender($this->display_handler->output);
        // Let modules modify the view output after it is rendered.
        $module_handler->invokeAll('views_post_render', [
            $this,
            &$this->display_handler->output,
            $cache,
        ]);
        // Let the themes play too, because post render is a very themey thing.
        foreach ($themes as $theme_name) {
            $function = $theme_name . '_views_post_render';
            if (function_exists($function)) {
                $function($this, $this->display_handler->output, $cache);
            }
        }
        return $this->display_handler->output;
    }
    
    /**
     * Gets the cache tags associated with the executed view.
     *
     * Note: The cache plugin controls the used tags, so you can override it, if
     *   needed.
     *
     * @return string[]
     *   An array of cache tags.
     */
    public function getCacheTags() {
        $this->initDisplay();
        
        /** @var \Drupal\views\Plugin\views\cache\CachePluginBase $cache */
        $cache = $this->display_handler
            ->getPlugin('cache');
        return $cache->getCacheTags();
    }
    
    /**
     * Builds the render array outline for the given display.
     *
     * This render array has a #pre_render callback which will call
     * ::executeDisplay in order to actually execute the view and then build the
     * final render array structure.
     *
     * @param string $display_id
     *   The display ID.
     * @param array $args
     *   An array of arguments passed along to the view.
     * @param bool $cache
     *   (optional) Should the result be render cached.
     *
     * @return array|null
     *   A renderable array with #type 'view' or NULL if the display ID was
     *   invalid.
     */
    public function buildRenderable($display_id = NULL, $args = [], $cache = TRUE) {
        // @todo Extract that into a generic method.
        if (empty($this->current_display) || $this->current_display != $this->chooseDisplay($display_id)) {
            if (!$this->setDisplay($display_id)) {
                return NULL;
            }
        }
        return $this->display_handler
            ->buildRenderable($args, $cache);
    }
    
    /**
     * Executes the given display, with the given arguments.
     *
     * To be called externally by whatever mechanism invokes the view,
     * such as a page callback, hook_block, etc.
     *
     * This function should NOT be used by anything external as this
     * returns data in the format specified by the display. It can also
     * have other side effects that are only intended for the 'proper'
     * use of the display, such as setting page titles.
     *
     * If you simply want to view the display, use View::preview() instead.
     *
     * @param string $display_id
     *   The display ID of the view to be executed.
     * @param string[] $args
     *   The arguments to be passed to the view.
     *
     * @return array|null
     *   A renderable array containing the view output or NULL if the display ID
     *   of the view to be executed doesn't exist.
     */
    public function executeDisplay($display_id = NULL, $args = []) {
        if (empty($this->current_display) || $this->current_display != $this->chooseDisplay($display_id)) {
            if (!$this->setDisplay($display_id)) {
                return NULL;
            }
        }
        $this->preExecute($args);
        // Execute the view
        $output = $this->display_handler
            ->execute();
        $this->postExecute();
        return $output;
    }
    
    /**
     * Previews the given display, with the given arguments.
     *
     * To be called externally, probably by an AJAX handler of some flavor.
     * Can also be called when views are embedded, as this guarantees
     * normalized output.
     *
     * This function does not do any access checks on the view. It is the
     * responsibility of the caller to check $view->access() or implement other
     * access logic. To render the view normally with access checks, use
     * views_embed_view() instead.
     *
     * @return array|null
     *   A renderable array containing the view output or NULL if the display ID
     *   of the view to be executed doesn't exist.
     */
    public function preview($display_id = NULL, $args = []) {
        if (empty($this->current_display) || !empty($display_id) && $this->current_display != $display_id) {
            if (!$this->setDisplay($display_id)) {
                return FALSE;
            }
        }
        $this->preview = TRUE;
        $this->preExecute($args);
        // Preview the view.
        $output = $this->display_handler
            ->preview();
        $this->postExecute();
        return $output;
    }
    
    /**
     * Runs attachments and lets the display do what it needs to before running.
     *
     * @param array $args
     *   An array of arguments from the URL that can be used by the view.
     */
    public function preExecute($args = []) {
        $this->old_view[] = views_get_current_view();
        views_set_current_view($this);
        $display_id = $this->current_display;
        // Prepare the view with the information we have, but only if we were
        // passed arguments, as they may have been set previously.
        if ($args) {
            $this->setArguments($args);
        }
        // Let modules modify the view just prior to executing it.
        \Drupal::moduleHandler()->invokeAll('views_pre_view', [
            $this,
            $display_id,
            &$this->args,
        ]);
        // Allow hook_views_pre_view() to set the dom_id, then ensure it is set.
        $this->dom_id = !empty($this->dom_id) ? $this->dom_id : hash('sha256', $this->storage
            ->id() . REQUEST_TIME . mt_rand());
        // Allow the display handler to set up for execution
        $this->display_handler
            ->preExecute();
    }
    
    /**
     * Unsets the current view, mostly.
     */
    public function postExecute() {
        // unset current view so we can be properly destructed later on.
        // Return the previous value in case we're an attachment.
        if ($this->old_view) {
            $old_view = array_pop($this->old_view);
        }
        views_set_current_view($old_view ?? FALSE);
    }
    
    /**
     * Runs attachment displays for the view.
     */
    public function attachDisplays() {
        if (!empty($this->is_attachment)) {
            return;
        }
        if (!$this->display_handler
            ->acceptAttachments()) {
            return;
        }
        $this->is_attachment = TRUE;
        // Find out which other displays attach to the current one.
        foreach ($this->display_handler
            ->getAttachedDisplays() as $id) {
            $display_handler = $this->displayHandlers
                ->get($id);
            // Only attach enabled attachments that the user has access to.
            if ($display_handler->isEnabled() && $display_handler->access()) {
                $cloned_view = Views::executableFactory()->get($this->storage);
                $display_handler->attachTo($cloned_view, $this->current_display, $this->element);
            }
        }
        $this->is_attachment = FALSE;
    }
    
    /**
     * Determines if the given user has access to the view.
     *
     * Note that this sets the display handler if it hasn't been set.
     *
     * @param string $displays
     *   The machine name of the display.
     * @param \Drupal\Core\Session\AccountInterface $account
     *   The user object.
     *
     * @return bool
     *   TRUE if the user has access to the view, FALSE otherwise.
     */
    public function access($displays = NULL, $account = NULL) {
        // No one should have access to disabled views.
        if (!$this->storage
            ->status()) {
            return FALSE;
        }
        if (!isset($this->current_display)) {
            $this->initDisplay();
        }
        if (!$account) {
            $account = $this->user;
        }
        // We can't use choose_display() here because that function
        // calls this one.
        $displays = (array) $displays;
        foreach ($displays as $display_id) {
            if ($this->displayHandlers
                ->has($display_id)) {
                if (($display = $this->displayHandlers
                    ->get($display_id)) && $display->access($account)) {
                    return TRUE;
                }
            }
        }
        return FALSE;
    }
    
    /**
     * Sets the used response object of the view.
     *
     * @param \Symfony\Component\HttpFoundation\Response $response
     *   The response object which should be set.
     */
    public function setResponse(Response $response) {
        $this->response = $response;
    }
    
    /**
     * Gets the response object used by the view.
     *
     * @return \Symfony\Component\HttpFoundation\Response
     *   The response object of the view.
     */
    public function getResponse() {
        if (!isset($this->response)) {
            $this->response = new Response();
        }
        return $this->response;
    }
    
    /**
     * Sets the request object.
     *
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The request object.
     */
    public function setRequest(Request $request) {
        $this->request = $request;
    }
    
    /**
     * Gets the request object.
     *
     * @return \Symfony\Component\HttpFoundation\Request
     *   The request object.
     */
    public function getRequest() {
        return $this->request;
    }
    
    /**
     * Gets the view's current title.
     *
     * This can change depending upon how it was built.
     *
     * @return string|false
     *   The view title, FALSE if the display is not set.
     */
    public function getTitle() {
        if (empty($this->display_handler)) {
            if (!$this->setDisplay('default')) {
                return FALSE;
            }
        }
        // During building, we might find a title override. If so, use it.
        if (!empty($this->build_info['title'])) {
            $title = $this->build_info['title'];
        }
        else {
            $title = $this->display_handler
                ->getOption('title');
        }
        // Allow substitutions from the first row.
        if ($this->initStyle()) {
            $title = $this->style_plugin
                ->tokenizeValue($title, 0);
        }
        return $title;
    }
    
    /**
     * Overrides the view's current title.
     *
     * The tokens in the title gets replaced before rendering.
     *
     * @return true
     *   Always returns TRUE.
     */
    public function setTitle($title) {
        $this->build_info['title'] = $title;
        return TRUE;
    }
    
    /**
     * Forces the view to build a title.
     */
    public function buildTitle() {
        $this->initDisplay();
        if (empty($this->built)) {
            $this->initQuery();
        }
        $this->initHandlers();
        $this->_buildArguments();
    }
    
    /**
     * Determines whether you can link to the view or a particular display.
     *
     * Some displays (e.g. block displays) do not have their own route, but may
     * optionally provide a link to another display that does have a route.
     *
     * @param array $args
     *   (optional) The arguments.
     * @param string $display_id
     *   (optional) The display ID. The current display will be used by default.
     *
     * @return bool
     *   TRUE if the current display has a valid route available, FALSE otherwise.
     */
    public function hasUrl($args = NULL, $display_id = NULL) {
        if (!empty($this->override_url)) {
            return TRUE;
        }
        // If the display has a valid route available (either its own or for a
        // linked display), then we can provide a URL for it.
        $display_handler = $this->displayHandlers
            ->get($display_id ?: $this->current_display)
            ->getRoutedDisplay();
        if (!$display_handler instanceof DisplayRouterInterface) {
            return FALSE;
        }
        // Look up the route name to make sure it exists.  The name may exist, but
        // not be available yet in some instances when editing a view and doing
        // a live preview.
        $provider = \Drupal::service('router.route_provider');
        try {
            $provider->getRouteByName($display_handler->getRouteName());
        } catch (RouteNotFoundException $e) {
            return FALSE;
        }
        return TRUE;
    }
    
    /**
     * Gets the URL for the current view.
     *
     * This URL will be adjusted for arguments.
     *
     * @param array $args
     *   (optional) Passed in arguments.
     * @param string $display_id
     *   (optional) Specify the display ID to link to, fallback to the current ID.
     *
     * @return \Drupal\Core\Url
     *   The URL of the current view.
     *
     * @throws \InvalidArgumentException
     *   Thrown when the current view doesn't have a route available.
     */
    public function getUrl($args = NULL, $display_id = NULL) {
        if (!empty($this->override_url)) {
            return $this->override_url;
        }
        $display_handler = $this->displayHandlers
            ->get($display_id ?: $this->current_display)
            ->getRoutedDisplay();
        if (!$display_handler instanceof DisplayRouterInterface) {
            throw new \InvalidArgumentException('You cannot create a URL to a display without routes.');
        }
        if (!isset($args)) {
            $args = $this->args;
            // Exclude arguments that were computed, not passed on the URL.
            $position = 0;
            if (!empty($this->argument)) {
                foreach ($this->argument as $argument) {
                    if (!empty($argument->is_default) && !empty($argument->options['default_argument_skip_url'])) {
                        unset($args[$position]);
                    }
                    $position++;
                }
            }
        }
        $path = $this->getPath();
        // Don't bother working if there's nothing to do:
        if (empty($path) || empty($args) && strpos($path, '%') === FALSE) {
            return $display_handler->getUrlInfo();
        }
        $argument_keys = isset($this->argument) ? array_keys($this->argument) : [];
        $id = current($argument_keys);
        
        /** @var \Drupal\Core\Url $url */
        $url = $display_handler->getUrlInfo();
        $route = $this->routeProvider
            ->getRouteByName($url->getRouteName());
        $variables = $route->compile()
            ->getVariables();
        $parameters = $url->getRouteParameters();
        foreach ($variables as $variable_name) {
            if (empty($args)) {
                // Try to never put % in a URL; use the wildcard instead.
                if ($id && !empty($this->argument[$id]->options['exception']['value'])) {
                    $parameters[$variable_name] = $this->argument[$id]->options['exception']['value'];
                }
                else {
                    // Provide some fallback in case no exception value could be found.
                    $parameters[$variable_name] = '*';
                }
            }
            else {
                $parameters[$variable_name] = array_shift($args);
            }
            if ($id) {
                $id = next($argument_keys);
            }
        }
        $url->setRouteParameters($parameters);
        return $url;
    }
    
    /**
     * Gets the Url object associated with the display handler.
     *
     * @param string $display_id
     *   (optional) The display ID (used only to detail an exception).
     *
     * @return \Drupal\Core\Url
     *   The display handlers URL object.
     *
     * @throws \InvalidArgumentException
     *   Thrown when the display plugin does not have a URL to return.
     */
    public function getUrlInfo($display_id = '') {
        $this->initDisplay();
        if (!$this->display_handler instanceof DisplayRouterInterface) {
            throw new \InvalidArgumentException("You cannot generate a URL for the display '{$display_id}'");
        }
        return $this->display_handler
            ->getUrlInfo();
    }
    
    /**
     * Gets the base path used for this view.
     *
     * @return string|false
     *   The base path used for the view or FALSE if setting the display fails.
     */
    public function getPath() {
        if (!empty($this->override_path)) {
            return $this->override_path;
        }
        if (empty($this->display_handler)) {
            if (!$this->setDisplay('default')) {
                return FALSE;
            }
        }
        return $this->display_handler
            ->getPath();
    }
    
    /**
     * Gets the current user.
     *
     * Views plugins can receive the current user in order to not need dependency
     * injection.
     *
     * @return \Drupal\Core\Session\AccountInterface
     *   The current user.
     */
    public function getUser() {
        return $this->user;
    }
    
    /**
     * Creates a duplicate ViewExecutable object.
     *
     * Makes a copy of this view that has been sanitized of handlers, any runtime
     * data, ID, and UUID.
     */
    public function createDuplicate() {
        return $this->storage
            ->createDuplicate()
            ->getExecutable();
    }
    
    /**
     * Unsets references so that a $view object may be properly garbage collected.
     */
    public function destroy() {
        foreach ($this::getHandlerTypes() as $type => $info) {
            if (isset($this->{$type})) {
                foreach ($this->{$type} as $handler) {
                    $handler->destroy();
                }
            }
        }
        if (isset($this->style_plugin)) {
            $this->style_plugin
                ->destroy();
        }
        $reflection = new \ReflectionClass($this);
        $defaults = $reflection->getDefaultProperties();
        // The external dependencies should not be reset. This is not generated by
        // the execution of a view.
        unset($defaults['storage'], $defaults['user'], $defaults['request'], $defaults['routeProvider'], $defaults['viewsData']);
        foreach ($defaults as $property => $default) {
            $this->{$property} = $default;
        }
    }
    
    /**
     * Makes sure the view is completely valid.
     *
     * @return array
     *   An array of error strings. This will be empty if there are no validation
     *   errors.
     */
    public function validate() {
        $errors = [];
        $this->initDisplay();
        $current_display = $this->current_display;
        foreach ($this->displayHandlers as $id => $display) {
            if (!empty($display)) {
                if (!empty($display->display['deleted'])) {
                    continue;
                }
                $result = $this->displayHandlers
                    ->get($id)
                    ->validate();
                if (!empty($result) && is_array($result)) {
                    $errors[$id] = $result;
                }
            }
        }
        $this->setDisplay($current_display);
        return $errors;
    }
    
    /**
     * Provides a list of views handler types used in a view.
     *
     * This also provides some information about the views handler types.
     *
     * @return array
     *   An array of associative arrays containing:
     *   - title: The title of the handler type.
     *   - ltitle: The lowercase title of the handler type.
     *   - stitle: A singular title of the handler type.
     *   - lstitle: A singular lowercase title of the handler type.
     *   - plural: Plural version of the handler type.
     *   - (optional) type: The actual internal used handler type. This key is
     *     just used for header,footer,empty to link to the internal type: area.
     */
    public static function getHandlerTypes() {
        return Views::getHandlerTypes();
    }
    
    /**
     * Returns the valid types of plugins that can be used.
     *
     * @return array
     *   An array of plugin type strings.
     */
    public static function getPluginTypes($type = NULL) {
        return Views::getPluginTypes($type);
    }
    
    /**
     * Adds an instance of a handler to the view.
     *
     * Items may be fields, filters, sort criteria, or arguments.
     *
     * @param string $display_id
     *   The machine name of the display.
     * @param string $type
     *   The type of handler being added.
     * @param string $table
     *   The name of the table this handler is from.
     * @param string $field
     *   The name of the field this handler is from.
     * @param array $options
     *   (optional) Extra options for this instance. Defaults to an empty array.
     * @param string $id
     *   (optional) A unique ID for this handler instance. Defaults to NULL, in
     *   which case one will be generated.
     *
     * @return string
     *   The unique ID for this handler instance.
     */
    public function addHandler($display_id, $type, $table, $field, $options = [], $id = NULL) {
        $types = $this::getHandlerTypes();
        $this->setDisplay($display_id);
        $data = $this->viewsData
            ->get($table);
        $fields = $this->displayHandlers
            ->get($display_id)
            ->getOption($types[$type]['plural']);
        if (empty($id)) {
            $id = $this->generateHandlerId($field, $fields);
        }
        // If the desired type is not found, use the original value directly.
        $handler_type = !empty($types[$type]['type']) ? $types[$type]['type'] : $type;
        $fields[$id] = [
            'id' => $id,
            'table' => $table,
            'field' => $field,
        ] + $options;
        if (isset($data['table']['entity type'])) {
            $fields[$id]['entity_type'] = $data['table']['entity type'];
        }
        if (isset($data[$field]['entity field'])) {
            $fields[$id]['entity_field'] = $data[$field]['entity field'];
        }
        // Load the plugin ID if available.
        if (isset($data[$field][$handler_type]['id'])) {
            $fields[$id]['plugin_id'] = $data[$field][$handler_type]['id'];
        }
        $this->displayHandlers
            ->get($display_id)
            ->setOption($types[$type]['plural'], $fields);
        return $id;
    }
    
    /**
     * Generates a unique ID for a handler instance.
     *
     * These handler instances are typically fields, filters, sort criteria, or
     * arguments.
     *
     * @param string $requested_id
     *   The requested ID for the handler instance.
     * @param array $existing_items
     *   An array of existing handler instances, keyed by their IDs.
     *
     * @return string
     *   A unique ID. This will be equal to $requested_id if no handler instance
     *   with that ID already exists. Otherwise, it will be appended with an
     *   integer to make it unique, e.g., "{$requested_id}_1",
     *   "{$requested_id}_2", etc.
     */
    public static function generateHandlerId($requested_id, $existing_items) {
        $count = 0;
        $id = $requested_id;
        while (!empty($existing_items[$id])) {
            $id = $requested_id . '_' . ++$count;
        }
        return $id;
    }
    
    /**
     * Gets an array of handler instances for the current display.
     *
     * @param string $type
     *   The type of handlers to retrieve.
     * @param string $display_id
     *   (optional) A specific display machine name to use. If NULL, the current
     *   display will be used.
     *
     * @return array
     *   An array of handler instances of a given type for this display.
     */
    public function getHandlers($type, $display_id = NULL) {
        $old_display_id = !empty($this->current_display) ? $this->current_display : 'default';
        $this->setDisplay($display_id);
        if (!isset($display_id)) {
            $display_id = $this->current_display;
        }
        // Get info about the types so we can get the right data.
        $types = static::getHandlerTypes();
        $handlers = $this->displayHandlers
            ->get($display_id)
            ->getOption($types[$type]['plural']);
        // Restore initial display id (if any) or set to 'default'.
        if ($display_id != $old_display_id) {
            $this->setDisplay($old_display_id);
        }
        return $handlers;
    }
    
    /**
     * Gets the configuration of a handler instance on a given display.
     *
     * @param string $display_id
     *   The machine name of the display.
     * @param string $type
     *   The type of handler to retrieve.
     * @param string $id
     *   The ID of the handler to retrieve.
     *
     * @return array|null
     *   Either the handler instance's configuration, or NULL if the handler is
     *   not used on the display.
     */
    public function getHandler($display_id, $type, $id) {
        // Get info about the types so we can get the right data.
        $types = static::getHandlerTypes();
        // Initialize the display
        $this->setDisplay($display_id);
        // Get the existing configuration
        $fields = $this->displayHandlers
            ->get($display_id)
            ->getOption($types[$type]['plural']);
        return $fields[$id] ?? NULL;
    }
    
    /**
     * Sets the configuration of a handler instance on a given display.
     *
     * @param string $display_id
     *   The machine name of the display.
     * @param string $type
     *   The type of handler being set.
     * @param string $id
     *   The ID of the handler being set.
     * @param array|null $item
     *   An array of configuration for a handler, or NULL to remove this instance.
     *
     * @see set_item_option()
     */
    public function setHandler($display_id, $type, $id, $item) {
        // Get info about the types so we can get the right data.
        $types = static::getHandlerTypes();
        // Initialize the display.
        $this->setDisplay($display_id);
        // Get the existing configuration.
        $fields = $this->displayHandlers
            ->get($display_id)
            ->getOption($types[$type]['plural']);
        if (isset($item)) {
            $fields[$id] = $item;
        }
        // Store.
        $this->displayHandlers
            ->get($display_id)
            ->setOption($types[$type]['plural'], $fields);
    }
    
    /**
     * Removes configuration for a handler instance on a given display.
     *
     * @param string $display_id
     *   The machine name of the display.
     * @param string $type
     *   The type of handler being removed.
     * @param string $id
     *   The ID of the handler being removed.
     */
    public function removeHandler($display_id, $type, $id) {
        // Get info about the types so we can get the right data.
        $types = static::getHandlerTypes();
        // Initialize the display.
        $this->setDisplay($display_id);
        // Get the existing configuration.
        $fields = $this->displayHandlers
            ->get($display_id)
            ->getOption($types[$type]['plural']);
        // Unset the item.
        unset($fields[$id]);
        // Store.
        $this->displayHandlers
            ->get($display_id)
            ->setOption($types[$type]['plural'], $fields);
    }
    
    /**
     * Sets an option on a handler instance.
     *
     * Use this only if you have just 1 or 2 options to set; if you have many,
     * consider getting the handler instance, adding the options and using
     * set_item() directly.
     *
     * @param string $display_id
     *   The machine name of the display.
     * @param string $type
     *   The type of handler being set.
     * @param string $id
     *   The ID of the handler being set.
     * @param string $option
     *   The configuration key for the value being set.
     * @param mixed $value
     *   The value being set.
     *
     * @see set_item()
     */
    public function setHandlerOption($display_id, $type, $id, $option, $value) {
        $item = $this->getHandler($display_id, $type, $id);
        $item[$option] = $value;
        $this->setHandler($display_id, $type, $id, $item);
    }
    
    /**
     * Enables admin links on the rendered view.
     *
     * @param bool $show_admin_links
     *   TRUE if the admin links should be shown.
     */
    public function setShowAdminLinks($show_admin_links) {
        $this->showAdminLinks = (bool) $show_admin_links;
    }
    
    /**
     * Returns whether admin links should be rendered on the view.
     *
     * @return bool
     *   TRUE if admin links should be rendered, else FALSE.
     */
    public function getShowAdminLinks() {
        if (!isset($this->showAdminLinks)) {
            return $this->getDisplay()
                ->getOption('show_admin_links');
        }
        return $this->showAdminLinks;
    }
    
    /**
     * Merges all plugin default values for each display.
     */
    public function mergeDefaults() {
        $this->initDisplay();
        // Initialize displays and merge all plugin defaults.
        foreach ($this->displayHandlers as $display) {
            $display->mergeDefaults();
        }
    }
    
    /**
     * Provides a full array of possible theme functions to try for a given hook.
     *
     * @param string $hook
     *   The hook to use. This is the base theme/template name.
     *
     * @return array
     *   An array of theme hook suggestions.
     */
    public function buildThemeFunctions($hook) {
        $themes = [];
        $display = isset($this->display_handler) ? $this->display_handler->display : NULL;
        $id = $this->storage
            ->id();
        if ($display) {
            $themes[] = $hook . '__' . $id . '__' . $display['id'];
            $themes[] = $hook . '__' . $display['id'];
            // Add theme suggestions for each single tag.
            foreach (Tags::explode($this->storage
                ->get('tag')) as $tag) {
                $themes[] = $hook . '__' . preg_replace('/[^a-z0-9]/', '_', strtolower($tag));
            }
            if ($display['id'] != $display['display_plugin']) {
                $themes[] = $hook . '__' . $id . '__' . $display['display_plugin'];
                $themes[] = $hook . '__' . $display['display_plugin'];
            }
        }
        $themes[] = $hook . '__' . $id;
        $themes[] = $hook;
        return $themes;
    }
    
    /**
     * Determines if this view has form elements.
     *
     * @return bool
     *   TRUE if this view contains handlers with views form implementations,
     *   FALSE otherwise.
     */
    public function hasFormElements() {
        if ($this->getDisplay()
            ->usesFields()) {
            foreach ($this->field as $field) {
                if (method_exists($field, 'viewsForm')) {
                    return TRUE;
                }
            }
        }
        $area_handlers = array_merge(array_values($this->header), array_values($this->footer));
        $empty = empty($this->result);
        foreach ($area_handlers as $area) {
            if (method_exists($area, 'viewsForm') && !$area->viewsFormEmpty($empty)) {
                return TRUE;
            }
        }
        return FALSE;
    }
    
    /**
     * Gets dependencies for the view.
     *
     * @see \Drupal\views\Entity\View::calculateDependencies()
     * @see \Drupal\views\Entity\View::getDependencies()
     *
     * @return array
     *   An array of dependencies grouped by type (module, theme, entity).
     */
    public function getDependencies() {
        return $this->storage
            ->calculateDependencies()
            ->getDependencies();
    }
    
    /**
     * Magic method implementation to serialize the view executable.
     *
     * @return array
     *   The names of all variables that should be serialized.
     */
    public function __sleep() {
        // Limit to only the required data which is needed to properly restore the
        // state during unserialization.
        $this->serializationData = [
            'storage' => $this->storage
                ->id(),
            'current_display' => $this->current_display,
            'args' => $this->args,
            'current_page' => $this->current_page,
            'exposed_input' => $this->exposed_input,
            'exposed_raw_input' => $this->exposed_raw_input,
            'exposed_data' => $this->exposed_data,
            'dom_id' => $this->dom_id,
            'executed' => $this->executed,
        ];
        return [
            'serializationData',
        ];
    }
    
    /**
     * Magic method implementation to unserialize the view executable.
     */
    public function __wakeup() {
        // There are cases, like in testing where we don't have a container
        // available.
        if (\Drupal::hasContainer() && !empty($this->serializationData)) {
            // Load and reference the storage.
            $this->storage = \Drupal::entityTypeManager()->getStorage('view')
                ->load($this->serializationData['storage']);
            $this->storage
                ->set('executable', $this);
            // Attach all necessary services.
            $this->user = \Drupal::currentUser();
            $this->viewsData = \Drupal::service('views.views_data');
            $this->routeProvider = \Drupal::service('router.route_provider');
            // Restore the state of this executable.
            if ($request = \Drupal::request()) {
                $this->setRequest($request);
            }
            $this->setDisplay($this->serializationData['current_display']);
            $this->setArguments($this->serializationData['args']);
            $this->setCurrentPage($this->serializationData['current_page']);
            $this->setExposedInput($this->serializationData['exposed_input']);
            $this->exposed_data = $this->serializationData['exposed_data'];
            $this->exposed_raw_input = $this->serializationData['exposed_raw_input'];
            $this->dom_id = $this->serializationData['dom_id'];
            $this->initHandlers();
            // If the display was previously executed, execute it now.
            if ($this->serializationData['executed']) {
                $this->execute($this->current_display);
            }
        }
        // Unset serializationData since it serves no further purpose.
        unset($this->serializationData);
    }

}