class QuickBlockContent

class QuickBlockContent extends QuickContent implements QuicktabContentInterface {
    
    /**
     * {@inheritdoc}
     */
    public static function getType() {
        return 'block';
    }
    
    /**
     * {@inheritdoc}
     */
    public function optionsForm($delta, $qt, $form_state) {
        $tab = $this->settings;
        $form = array();
        $form['block']['bid'] = array(
            '#type' => 'select',
            '#options' => quicktabs_get_blocks(),
            '#default_value' => isset($tab['bid']) ? $tab['bid'] : '',
            '#title' => t('Select a block'),
        );
        $form['block']['hide_title'] = array(
            '#type' => 'checkbox',
            '#title' => t('Hide the title of this block'),
            '#default_value' => isset($tab['hide_title']) ? $tab['hide_title'] : 1,
        );
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function render($hide_empty = FALSE, $args = array()) {
        if ($this->rendered_content) {
            return $this->rendered_content;
        }
        $output = array();
        $item = $this->settings;
        if (!empty($args)) {
            // The args have been passed in from an ajax request.
            $qt_name = array_shift($args);
            list($item['bid'], $item['hide_title']) = $args;
            // Ensure the block is assigned to the requested quicktabs block. This test prevents
            // AJAX access to blocks that have not been added to an AJAX-enabled quicktabs block.
            $break = TRUE;
            $quicktabs = quicktabs_load($qt_name);
            // Ensure AJAX is enabled for the quicktabs block.
            if (!empty($quicktabs) && $quicktabs->ajax == 1) {
                // Ensure the requested tab has been added to the quicktabs block.
                foreach ($quicktabs->tabs as $quicktab) {
                    if (isset($quicktab['bid']) && $quicktab['bid'] == $item['bid']) {
                        $break = FALSE;
                        break;
                    }
                }
            }
            if ($break == TRUE) {
                if (!$hide_empty) {
                    $output['#markup'] = theme('quicktabs_tab_access_denied', $item);
                }
                return $output;
            }
        }
        if (isset($item['bid'])) {
            if (\Drupal::moduleHandler()->moduleExists('block')) {
                $pos = strpos($item['bid'], '_delta_');
                $module = drupal_substr($item['bid'], 0, $pos);
                $delta = drupal_substr($item['bid'], $pos + 7);
                // Make sure the user can access the block.
                if ($this->accessBlock($module, $delta)) {
                    $block = block_load($module, $delta);
                    $block->region = 'quicktabs_tabpage';
                    if ($block_arr = _block_render_blocks(array(
                        $block,
                    ))) {
                        if ($item['hide_title']) {
                            $block_arr["{$block->module}_{$block->delta}"]->subject = FALSE;
                        }
                        if (!empty($block_arr["{$block->module}_{$block->delta}"]->content)) {
                            $build = _block_get_renderable_array($block_arr);
                            $output = $build;
                        }
                    }
                }
                elseif (!$hide_empty) {
                    $output['#markup'] = theme('quicktabs_tab_access_denied', $item);
                }
            }
            elseif (!$hide_empty) {
                $output['#markup'] = t('Block module is not enabled, cannot display content.');
            }
        }
        $this->rendered_content = $output;
        return $output;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getAjaxKeys() {
        return array(
            'bid',
            'hide_title',
        );
    }
    
    /**
     * {@inheritdoc}
     */
    public function getUniqueKeys() {
        return array(
            'bid',
        );
    }
    
    /**
     * Checks if the current user can access a block.
     */
    private function accessBlock($module, $delta) {
        // Get current user's rids.
        global $user;
        $rids = array_keys($user->roles);
        // Get authorized rids.
        $authorized_rids = db_select('block_role', 'br')->fields('br', array(
            'rid',
        ))
            ->condition('module', $module, '=')
            ->condition('delta', $delta, '=')
            ->execute()
            ->fetchCol('rid');
        // Return whether the user can access the block:
        // - Either all roles have access - no record in {block_role}
        // - Or only specific roles have access - in which case rids should match.
        return count($authorized_rids) == 0 || count(array_intersect($authorized_rids, $rids)) != 0;
    }

}