class views_plugin_row_rss_fields

class views_plugin_row_rss_fields extends views_plugin_row {
    
    /**
     * {@inheritdoc}
     */
    public function option_definition() {
        $options = parent::option_definition();
        $options['title_field'] = array(
            'default' => '',
        );
        $options['link_field'] = array(
            'default' => '',
        );
        $options['description_field'] = array(
            'default' => '',
        );
        $options['creator_field'] = array(
            'default' => '',
        );
        $options['date_field'] = array(
            'default' => '',
        );
        $options['guid_field_options']['guid_field'] = array(
            'default' => '',
        );
        $options['guid_field_options']['guid_field_is_permalink'] = array(
            'default' => TRUE,
            'bool' => TRUE,
        );
        return $options;
    }
    
    /**
     * {@inheritdoc}
     */
    public function options_form(&$form, &$form_state) {
        parent::options_form($form, $form_state);
        $initial_labels = array(
            '' => t('- None -'),
        );
        $view_fields_labels = $this->display->handler
            ->get_field_labels();
        $view_fields_labels = array_merge($initial_labels, $view_fields_labels);
        $form['title_field'] = array(
            '#type' => 'select',
            '#title' => t('Title field'),
            '#description' => t('The field that is going to be used as the RSS item title for each row.'),
            '#options' => $view_fields_labels,
            '#default_value' => $this->options['title_field'],
            '#required' => TRUE,
        );
        $form['link_field'] = array(
            '#type' => 'select',
            '#title' => t('Link field'),
            '#description' => t('The field that is going to be used as the RSS item link for each row. This must be a drupal relative path.'),
            '#options' => $view_fields_labels,
            '#default_value' => $this->options['link_field'],
            '#required' => TRUE,
        );
        $form['description_field'] = array(
            '#type' => 'select',
            '#title' => t('Description field'),
            '#description' => t('The field that is going to be used as the RSS item description for each row.'),
            '#options' => $view_fields_labels,
            '#default_value' => $this->options['description_field'],
            '#required' => TRUE,
        );
        $form['creator_field'] = array(
            '#type' => 'select',
            '#title' => t('Creator field'),
            '#description' => t('The field that is going to be used as the RSS item creator for each row.'),
            '#options' => $view_fields_labels,
            '#default_value' => $this->options['creator_field'],
            '#required' => TRUE,
        );
        $form['date_field'] = array(
            '#type' => 'select',
            '#title' => t('Publication date field'),
            '#description' => t('The field that is going to be used as the RSS item pubDate for each row. It needs to be in RFC 2822 format.'),
            '#options' => $view_fields_labels,
            '#default_value' => $this->options['date_field'],
            '#required' => TRUE,
        );
        $form['guid_field_options'] = array(
            '#type' => 'fieldset',
            '#title' => t('GUID settings'),
            '#collapsible' => FALSE,
            '#collapsed' => FALSE,
        );
        $form['guid_field_options']['guid_field'] = array(
            '#type' => 'select',
            '#title' => t('GUID field'),
            '#description' => t('The globally unique identifier of the RSS item.'),
            '#options' => $view_fields_labels,
            '#default_value' => $this->options['guid_field_options']['guid_field'],
            '#required' => TRUE,
        );
        $form['guid_field_options']['guid_field_is_permalink'] = array(
            '#type' => 'checkbox',
            '#title' => t('GUID is permalink'),
            '#description' => t('The RSS item GUID is a permalink.'),
            '#default_value' => $this->options['guid_field_options']['guid_field_is_permalink'],
        );
    }
    
    /**
     *
     */
    public function validate() {
        $errors = parent::validate();
        $required_options = array(
            'title_field',
            'link_field',
            'description_field',
            'creator_field',
            'date_field',
        );
        foreach ($required_options as $required_option) {
            if (empty($this->options[$required_option])) {
                $errors[] = t('Row style plugin requires specifying which views fields to use for RSS item.');
                break;
            }
        }
        // Once more for guid.
        if (empty($this->options['guid_field_options']['guid_field'])) {
            $errors[] = t('Row style plugin requires specifying which views fields to use for RSS item.');
        }
        return $errors;
    }
    
    /**
     * {@inheritdoc}
     */
    public function render($row) {
        static $row_index;
        if (!isset($row_index)) {
            $row_index = 0;
        }
        if (function_exists('rdf_get_namespaces')) {
            // Merge RDF namespaces in the XML namespaces in case they are used
            // further in the RSS content.
            $xml_rdf_namespaces = array();
            foreach (rdf_get_namespaces() as $prefix => $uri) {
                $xml_rdf_namespaces['xmlns:' . $prefix] = $uri;
            }
            $this->view->style_plugin->namespaces += $xml_rdf_namespaces;
        }
        // Create the RSS item object.
        $item = new stdClass();
        $item->title = $this->get_field($row_index, $this->options['title_field']);
        $item->link = url($this->get_field($row_index, $this->options['link_field']), array(
            'absolute' => TRUE,
        ));
        $item->description = $this->get_field($row_index, $this->options['description_field']);
        $item->elements = array(
            array(
                'key' => 'pubDate',
                'value' => $this->get_field($row_index, $this->options['date_field']),
            ),
            array(
                'key' => 'dc:creator',
                'value' => $this->get_field($row_index, $this->options['creator_field']),
                'namespace' => array(
                    'xmlns:dc' => 'http://purl.org/dc/elements/1.1/',
                ),
            ),
        );
        $guid_is_permalink_string = 'false';
        $item_guid = $this->get_field($row_index, $this->options['guid_field_options']['guid_field']);
        if ($this->options['guid_field_options']['guid_field_is_permalink']) {
            $guid_is_permalink_string = 'true';
            $item_guid = url($item_guid, array(
                'absolute' => TRUE,
            ));
        }
        $item->elements[] = array(
            'key' => 'guid',
            'value' => $item_guid,
            'attributes' => array(
                'isPermaLink' => $guid_is_permalink_string,
            ),
        );
        $row_index++;
        foreach ($item->elements as $element) {
            if (isset($element['namespace'])) {
                $this->view->style_plugin->namespaces = array_merge($this->view->style_plugin->namespaces, $element['namespace']);
            }
        }
        return theme($this->theme_functions(), array(
            'view' => $this->view,
            'options' => $this->options,
            'row' => $item,
            'field_alias' => isset($this->field_alias) ? $this->field_alias : '',
        ));
    }
    
    /**
     * Retrieves a views field value from the style plugin.
     *
     * @param int $index
     *   The index of the row as expected by views_plugin_style::get_field().
     * @param string $field_id
     *   The ID assigned to the required field in the display.
     */
    public function get_field($index, $field_id) {
        if (empty($this->view->style_plugin) || !is_object($this->view->style_plugin) || empty($field_id)) {
            return '';
        }
        return $this->view->style_plugin
            ->get_field($index, $field_id);
    }

}