class Block

class Block extends CoreBlock {
    
    /**
     * The views filter plugin manager.
     *
     * @var \Drupal\views\Plugin\ViewsHandlerManager
     */
    protected $filterManager;
    
    /**
     * The current request.
     *
     * @var \Symfony\Component\HttpFoundation\Request
     */
    protected $request;
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        
        /**
         * @var \Drupal\ctools_views\Plugin\Display\Block
         */
        $instance = parent::create($container, $configuration, $plugin_id, $plugin_definition);
        $instance->filterManager = $container->get('plugin.manager.views.filter');
        $instance->request = $container->get('request_stack')
            ->getCurrentRequest();
        return $instance;
    }
    
    /**
     * {@inheritdoc}
     */
    public function optionsSummary(&$categories, &$options) {
        parent::optionsSummary($categories, $options);
        $filtered_allow = array_filter($this->getOption('allow'));
        $filter_options = [
            'items_per_page' => $this->t('Items per page'),
            'offset' => $this->t('Pager offset'),
            'pager' => $this->t('Pager type'),
            'hide_fields' => $this->t('Hide fields'),
            'sort_fields' => $this->t('Reorder fields'),
            'disable_filters' => $this->t('Disable filters'),
            'configure_sorts' => $this->t('Configure sorts'),
        ];
        $filter_intersect = array_intersect_key($filter_options, $filtered_allow);
        $options['allow'] = [
            'category' => 'block',
            'title' => $this->t('Allow settings'),
            'value' => empty($filtered_allow) ? $this->t('None') : implode(', ', $filter_intersect),
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildOptionsForm(&$form, FormStateInterface $form_state) {
        parent::buildOptionsForm($form, $form_state);
        $form['allow']['#options']['offset'] = $this->t('Pager offset');
        $form['allow']['#options']['pager'] = $this->t('Pager type');
        $form['allow']['#options']['hide_fields'] = $this->t('Hide fields');
        $form['allow']['#options']['sort_fields'] = $this->t('Reorder fields');
        $form['allow']['#options']['disable_filters'] = $this->t('Disable filters');
        $form['allow']['#options']['configure_sorts'] = $this->t('Configure sorts');
        $defaults = [];
        if (!empty($form['allow']['#default_value'])) {
            $defaults = array_filter($form['allow']['#default_value']);
            if (!empty($defaults['items_per_page'])) {
                $defaults['items_per_page'] = 'items_per_page';
            }
        }
        $form['allow']['#default_value'] = $defaults;
    }
    
    /**
     * {@inheritdoc}
     */
    public function blockForm(ViewsBlock $block, array &$form, FormStateInterface $form_state) {
        $form = parent::blockForm($block, $form, $form_state);
        $allow_settings = array_filter($this->getOption('allow'));
        $block_configuration = $block->getConfiguration();
        // Modify "Items per page" block settings form.
        if (!empty($allow_settings['items_per_page'])) {
            // Items per page.
            $form['override']['items_per_page']['#type'] = 'number';
            unset($form['override']['items_per_page']['#options']);
        }
        // Provide "Pager offset" block settings form.
        if (!empty($allow_settings['offset'])) {
            $form['override']['pager_offset'] = [
                '#type' => 'number',
                '#title' => $this->t('Pager offset'),
                '#default_value' => $block_configuration['pager_offset'] ?? 0,
                '#description' => $this->t('For example, set this to 3 and the first 3 items will not be displayed.'),
            ];
        }
        // Provide "Pager type" block settings form.
        if (!empty($allow_settings['pager'])) {
            $pager_options = [
                'view' => $this->t('Inherit from view'),
                'some' => $this->t('Display a specified number of items'),
                'none' => $this->t('Display all items'),
            ];
            $form['override']['pager'] = [
                '#type' => 'radios',
                '#title' => $this->t('Pager'),
                '#options' => $pager_options,
                '#default_value' => $block_configuration['pager'] ?? 'view',
            ];
        }
        // Provide "Hide fields" / "Reorder fields" block settings form.
        if (!empty($allow_settings['hide_fields']) || !empty($allow_settings['sort_fields'])) {
            // Set up the configuration table for hiding / sorting fields.
            $fields = $this->getHandlers('field');
            $header = [];
            if (!empty($allow_settings['hide_fields'])) {
                $header['hide'] = $this->t('Hide');
            }
            $header['label'] = $this->t('Label');
            if (!empty($allow_settings['sort_fields'])) {
                $header['weight'] = $this->t('Weight');
            }
            $form['override']['order_fields'] = [
                '#type' => 'table',
                '#header' => $header,
                '#rows' => [],
            ];
            if (!empty($allow_settings['sort_fields'])) {
                $form['override']['order_fields']['#tabledrag'] = [
                    [
                        'action' => 'order',
                        'relationship' => 'sibling',
                        'group' => 'field-weight',
                    ],
                ];
                $form['override']['order_fields']['#attributes'] = [
                    'id' => 'order-fields',
                ];
            }
            // Sort available field plugins by their currently configured weight.
            $sorted_fields = [];
            if (!empty($allow_settings['sort_fields']) && isset($block_configuration['fields'])) {
                uasort($block_configuration['fields'], '\\Drupal\\ctools_views\\Plugin\\Display\\Block::sortFieldsByWeight');
                foreach (array_keys($block_configuration['fields']) as $field_name) {
                    if (!empty($fields[$field_name])) {
                        $sorted_fields[$field_name] = $fields[$field_name];
                        unset($fields[$field_name]);
                    }
                }
                if (!empty($fields)) {
                    foreach ($fields as $field_name => $field_info) {
                        $sorted_fields[$field_name] = $field_info;
                    }
                }
            }
            else {
                $sorted_fields = $fields;
            }
            // Add each field to the configuration table.
            foreach ($sorted_fields as $field_name => $plugin) {
                $field_label = $plugin->adminLabel();
                if (!empty($plugin->options['label'])) {
                    $field_label .= ' (' . $plugin->options['label'] . ')';
                }
                if (!empty($allow_settings['sort_fields'])) {
                    $form['override']['order_fields'][$field_name]['#attributes']['class'][] = 'draggable';
                }
                $form['override']['order_fields'][$field_name]['#weight'] = !empty($block_configuration['fields'][$field_name]['weight']) ? $block_configuration['fields'][$field_name]['weight'] : 0;
                if (!empty($allow_settings['hide_fields'])) {
                    $form['override']['order_fields'][$field_name]['hide'] = [
                        '#type' => 'checkbox',
                        '#default_value' => !empty($block_configuration['fields'][$field_name]['hide']) ? $block_configuration['fields'][$field_name]['hide'] : 0,
                    ];
                }
                $form['override']['order_fields'][$field_name]['label'] = [
                    '#markup' => $field_label,
                ];
                if (!empty($allow_settings['sort_fields'])) {
                    $form['override']['order_fields'][$field_name]['weight'] = [
                        '#type' => 'weight',
                        '#title' => $this->t('Weight for @title', [
                            '@title' => $field_label,
                        ]),
                        '#title_display' => 'invisible',
                        '#delta' => 50,
                        '#default_value' => !empty($block_configuration['fields'][$field_name]['weight']) ? $block_configuration['fields'][$field_name]['weight'] : 0,
                        '#attributes' => [
                            'class' => [
                                'field-weight',
                            ],
                        ],
                    ];
                }
            }
        }
        // Provide "Configure filters" / "Disable filters" block settings form.
        if (!empty($allow_settings['disable_filters'])) {
            $items = [];
            foreach ((array) $this->getOption('filters') as $filter_name => $item) {
                $item['value'] = $block_configuration["filter"][$filter_name]['value'] ?? '';
                $items[$filter_name] = $item;
            }
            $this->setOption('filters', $items);
            $filters = $this->getHandlers('filter');
            // Add a settings form for each exposed filter to configure or hide it.
            foreach ($filters as $filter_name => $plugin) {
                if ($plugin->isExposed() && ($exposed_info = $plugin->exposedInfo())) {
                    $form['override']['filters'][$filter_name] = [
                        '#type' => 'details',
                        '#title' => $exposed_info['label'],
                    ];
                    $form['override']['filters'][$filter_name]['plugin'] = [
                        '#type' => 'value',
                        '#value' => $plugin,
                    ];
                    // Render "Disable filters" settings form.
                    if (!empty($allow_settings['disable_filters'])) {
                        $form['override']['filters'][$filter_name]['disable'] = [
                            '#type' => 'checkbox',
                            '#title' => $this->t('Disable'),
                            '#default_value' => !empty($block_configuration['filter'][$filter_name]['disable']) ? $block_configuration['filter'][$filter_name]['disable'] : 0,
                        ];
                    }
                }
            }
        }
        // Provide "Configure sorts" block settings form.
        if (!empty($allow_settings['configure_sorts'])) {
            $sorts = $this->getHandlers('sort');
            $options = [
                'ASC' => $this->t('Sort ascending'),
                'DESC' => $this->t('Sort descending'),
            ];
            foreach ($sorts as $sort_name => $plugin) {
                $form['override']['sort'][$sort_name] = [
                    '#type' => 'details',
                    '#title' => $plugin->adminLabel(),
                ];
                $form['override']['sort'][$sort_name]['plugin'] = [
                    '#type' => 'value',
                    '#value' => $plugin,
                ];
                $form['override']['sort'][$sort_name]['order'] = [
                    '#title' => $this->t('Order'),
                    '#type' => 'radios',
                    '#options' => $options,
                    '#default_value' => $plugin->options['order'],
                ];
                // Set default values for sorts for this block.
                if (!empty($block_configuration["sort"][$sort_name])) {
                    $form['override']['sort'][$sort_name]['order']['#default_value'] = $block_configuration["sort"][$sort_name];
                }
            }
        }
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function blockSubmit(ViewsBlock $block, $form, FormStateInterface $form_state) {
        // Set default value for items_per_page if left blank.
        if (empty($form_state->getValue([
            'override',
            'items_per_page',
        ]))) {
            $form_state->setValue([
                'override',
                'items_per_page',
            ], "none");
        }
        parent::blockSubmit($block, $form, $form_state);
        $configuration = $block->getConfiguration();
        $allow_settings = array_filter($this->getOption('allow'));
        // Save "Pager type" settings to block configuration.
        if (!empty($allow_settings['pager'])) {
            if ($pager = $form_state->getValue([
                'override',
                'pager',
            ])) {
                $configuration['pager'] = $pager;
            }
        }
        // Save "Pager offset" settings to block configuration.
        if (!empty($allow_settings['offset'])) {
            $configuration['pager_offset'] = $form_state->getValue([
                'override',
                'pager_offset',
            ]);
        }
        // Save "Hide fields" / "Reorder fields" settings to block configuration.
        if (!empty($allow_settings['hide_fields']) || !empty($allow_settings['sort_fields'])) {
            if ($fields = array_filter($form_state->getValue([
                'override',
                'order_fields',
            ]))) {
                uasort($fields, '\\Drupal\\ctools_views\\Plugin\\Display\\Block::sortFieldsByWeight');
                $configuration['fields'] = $fields;
            }
        }
        // Save "Configure filters" / "Disable filters" settings to block
        // configuration.
        unset($configuration['filter']);
        if (!empty($allow_settings['disable_filters'])) {
            if ($filters = $form_state->getValue([
                'override',
                'filters',
            ])) {
                foreach ($filters as $filter_name => $filter) {
                    
                    /** @var \Drupal\views\Plugin\views\filter\FilterPluginBase $plugin */
                    $plugin = $form_state->getValue([
                        'override',
                        'filters',
                        $filter_name,
                        'plugin',
                    ]);
                    $configuration["filter"][$filter_name]['type'] = $plugin->getPluginId();
                    // Check if we want to disable this filter.
                    if (!empty($allow_settings['disable_filters'])) {
                        $disable = $form_state->getValue([
                            'override',
                            'filters',
                            $filter_name,
                            'disable',
                        ]);
                        // If marked disabled, we don't really care about other stuff.
                        if ($disable) {
                            $configuration["filter"][$filter_name]['disable'] = $disable;
                            continue;
                        }
                    }
                }
            }
        }
        // Save "Configure sorts" settings to block configuration.
        if (!empty($allow_settings['configure_sorts'])) {
            $sorts = $form_state->getValue([
                'override',
                'sort',
            ]);
            foreach ($sorts as $sort_name => $sort) {
                $plugin = $sort['plugin'];
                // Check if we want to override the default sort order.
                if ($plugin->options['order'] != $sort['order']) {
                    $configuration['sort'][$sort_name] = $sort['order'];
                }
            }
        }
        $block->setConfiguration($configuration);
    }
    
    /**
     * {@inheritdoc}
     */
    public function preBlockBuild(ViewsBlock $block) {
        parent::preBlockBuild($block);
        $allow_settings = array_filter($this->getOption('allow'));
        $config = $block->getConfiguration();
        [
            ,
            $display_id,
        ] = explode('-', $block->getDerivativeId(), 2);
        // Change pager offset settings based on block configuration.
        if (!empty($allow_settings['offset']) && isset($config['pager_offset'])) {
            $this->view
                ->setOffset($config['pager_offset']);
        }
        // Change pager style settings based on block configuration.
        if (!empty($allow_settings['pager'])) {
            $pager = $this->view->display_handler
                ->getOption('pager');
            if (!empty($config['pager']) && $config['pager'] != 'view') {
                $pager['type'] = $config['pager'];
            }
            $this->view->display_handler
                ->setOption('pager', $pager);
        }
        // Change fields output based on block configuration.
        if (!empty($allow_settings['hide_fields']) || !empty($allow_settings['sort_fields'])) {
            if (!empty($config['fields']) && $this->view
                ->getStyle()
                ->usesFields()) {
                $fields = $this->view
                    ->getHandlers('field');
                uasort($config['fields'], '\\Drupal\\ctools_views\\Plugin\\Display\\Block::sortFieldsByWeight');
                $iterate_fields = !empty($allow_settings['sort_fields']) ? $config['fields'] : $fields;
                foreach (array_keys($iterate_fields) as $field_name) {
                    // Remove each field in sequence and re-add them to sort
                    // appropriately or hide if disabled.
                    $this->view
                        ->removeHandler($display_id, 'field', $field_name);
                    if (empty($allow_settings['hide_fields']) || !empty($allow_settings['hide_fields']) && empty($config['fields'][$field_name]['hide'])) {
                        $this->view
                            ->addHandler($display_id, 'field', $fields[$field_name]['table'], $fields[$field_name]['field'], $fields[$field_name], $field_name);
                    }
                }
            }
        }
        // Change filters output based on block configuration.
        if (!empty($allow_settings['disable_filters'])) {
            $filters = $this->view
                ->getHandlers('filter', $display_id);
            foreach ($filters as $filter_name => $filter) {
                // If we allow disabled filters and this filter is disabled, disable it
                // and continue.
                if (!empty($allow_settings['disable_filters']) && !empty($config["filter"][$filter_name]['disable'])) {
                    $this->view
                        ->removeHandler($display_id, 'filter', $filter_name);
                    continue;
                }
            }
        }
        // Change sorts based on block configuration.
        if (!empty($allow_settings['configure_sorts'])) {
            $sorts = $this->view
                ->getHandlers('sort', $display_id);
            foreach ($sorts as $sort_name => $sort) {
                if (!empty($config["sort"][$sort_name])) {
                    $sort['order'] = $config["sort"][$sort_name];
                    $this->view
                        ->setHandler($display_id, 'sort', $sort_name, $sort);
                }
            }
        }
    }
    
    /**
     * Filter options value.
     */
    protected function getFilterOptionsValue(array $filter, array $config) {
        $plugin_definition = $this->filterManager
            ->getDefinition($config['type']);
        if (is_subclass_of($plugin_definition['class'], '\\Drupal\\views\\Plugin\\views\\filter\\InOperator')) {
            return array_values($config['value']);
        }
        return $config['value'][$filter['expose']['identifier']];
    }
    
    /**
     * Exposed widgets.
     *
     * Exposed widgets typically only work with ajax in Drupal core, however
     * #2605218 totally breaks the rest of the functionality in this display and
     * in Core's Block display as well, so we allow non-ajax block views to use
     * exposed filters and manually set the #action to the current request uri.
     */
    public function elementPreRender(array $element) {
        
        /** @var \Drupal\views\ViewExecutable $view */
        $view = $element['#view'];
        if (!empty($view->exposed_widgets['#action']) && !$view->ajaxEnabled()) {
            $view->exposed_widgets['#action'] = $this->request
                ->getRequestUri();
        }
        return parent::elementPreRender($element);
    }
    
    /**
     * Sort field config array by weight.
     *
     * @param int $a
     *   The field a.
     * @param int $b
     *   The field b.
     *
     * @return int
     *   Return the more weight
     */
    public static function sortFieldsByWeight($a, $b) {
        $a_weight = $a['weight'] ?? 0;
        $b_weight = $b['weight'] ?? 0;
        if ($a_weight == $b_weight) {
            return 0;
        }
        return $a_weight < $b_weight ? -1 : 1;
    }

}