class views_handler_sort

class views_handler_sort extends views_handler {
    
    /**
     * Determine if a sort can be exposed.
     */
    public function can_expose() {
        return TRUE;
    }
    
    /**
     * Called to add the sort to a query.
     */
    public function query() {
        $this->ensure_my_table();
        // Add the field.
        $this->query
            ->add_orderby($this->table_alias, $this->real_field, $this->options['order']);
    }
    
    /**
     * {@inheritdoc}
     */
    public function option_definition() {
        $options = parent::option_definition();
        $options['order'] = array(
            'default' => 'ASC',
        );
        $options['exposed'] = array(
            'default' => FALSE,
            'bool' => TRUE,
        );
        $options['expose'] = array(
            'contains' => array(
                'label' => array(
                    'default' => '',
                    'translatable' => TRUE,
                ),
            ),
        );
        return $options;
    }
    
    /**
     * Display whether or not the sort order is ascending or descending.
     */
    public function admin_summary() {
        if (!empty($this->options['exposed'])) {
            return t('Exposed');
        }
        switch ($this->options['order']) {
            case 'ASC':
            case 'asc':
            default:
                return t('asc');
            case 'DESC':
            case 'desc':
                return t('desc');
        }
    }
    
    /**
     * Basic options for all sort criteria.
     */
    public function options_form(&$form, &$form_state) {
        parent::options_form($form, $form_state);
        if ($this->can_expose()) {
            $this->show_expose_button($form, $form_state);
        }
        $form['op_val_start'] = array(
            '#value' => '<div class="clearfix">',
        );
        $this->show_sort_form($form, $form_state);
        $form['op_val_end'] = array(
            '#value' => '</div>',
        );
        if ($this->can_expose()) {
            $this->show_expose_form($form, $form_state);
        }
    }
    
    /**
     * Shortcut to display the expose/hide button.
     */
    public function show_expose_button(&$form, &$form_state) {
        $form['expose_button'] = array(
            '#prefix' => '<div class="views-expose clearfix">',
            '#suffix' => '</div>',
            // Should always come first.
'#weight' => -1000,
        );
        // Add a checkbox for JS users, which will have behavior attached to it
        // so it can replace the button.
        $form['expose_button']['checkbox'] = array(
            '#theme_wrappers' => array(
                'container',
            ),
            '#attributes' => array(
                'class' => array(
                    'js-only',
                ),
            ),
        );
        $form['expose_button']['checkbox']['checkbox'] = array(
            '#title' => t('Expose this sort to visitors, to allow them to change it'),
            '#type' => 'checkbox',
        );
        // Then add the button itself.
        if (empty($this->options['exposed'])) {
            $form['expose_button']['markup'] = array(
                '#markup' => '<div class="description exposed-description" style="float: left; margin-right:10px">' . t('This sort is not exposed. Expose it to allow the users to change it.') . '</div>',
            );
            $form['expose_button']['button'] = array(
                '#limit_validation_errors' => array(),
                '#type' => 'submit',
                '#value' => t('Expose sort'),
                '#submit' => array(
                    'views_ui_config_item_form_expose',
                ),
            );
            $form['expose_button']['checkbox']['checkbox']['#default_value'] = 0;
        }
        else {
            $form['expose_button']['markup'] = array(
                '#markup' => '<div class="description exposed-description">' . t('This sort is exposed. If you hide it, users will not be able to change it.') . '</div>',
            );
            $form['expose_button']['button'] = array(
                '#limit_validation_errors' => array(),
                '#type' => 'submit',
                '#value' => t('Hide sort'),
                '#submit' => array(
                    'views_ui_config_item_form_expose',
                ),
            );
            $form['expose_button']['checkbox']['checkbox']['#default_value'] = 1;
        }
    }
    
    /**
     * Simple validate handler.
     */
    public function options_validate(&$form, &$form_state) {
        $this->sort_validate($form, $form_state);
        if (!empty($this->options['exposed'])) {
            $this->expose_validate($form, $form_state);
        }
    }
    
    /**
     * Simple submit handler.
     */
    public function options_submit(&$form, &$form_state) {
        // Don't store this.
        unset($form_state['values']['expose_button']);
        $this->sort_submit($form, $form_state);
        if (!empty($this->options['exposed'])) {
            $this->expose_submit($form, $form_state);
        }
    }
    
    /**
     * Shortcut to display the value form.
     */
    public function show_sort_form(&$form, &$form_state) {
        $options = $this->sort_options();
        if (!empty($options)) {
            $form['order'] = array(
                '#type' => 'radios',
                '#options' => $options,
                '#default_value' => $this->options['order'],
            );
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function sort_validate(&$form, &$form_state) {
    }
    
    /**
     * {@inheritdoc}
     */
    public function sort_submit(&$form, &$form_state) {
    }
    
    /**
     * Provide a list of options for the default sort form.
     *
     * Should be overridden by classes that don't override sort_form.
     */
    public function sort_options() {
        return array(
            'ASC' => t('Sort ascending'),
            'DESC' => t('Sort descending'),
        );
    }
    
    /**
     * {@inheritdoc}
     */
    public function expose_form(&$form, &$form_state) {
        // #flatten will move everything from $form['expose'][$key] to $form[$key]
        // prior to rendering. That's why the pre_render for it needs to run first,
        // so that when the next pre_render (the one for fieldsets) runs, it gets
        // the flattened data.
        array_unshift($form['#pre_render'], 'views_ui_pre_render_flatten_data');
        $form['expose']['#flatten'] = TRUE;
        $form['expose']['label'] = array(
            '#type' => 'textfield',
            '#default_value' => $this->options['expose']['label'],
            '#title' => t('Label'),
            '#required' => TRUE,
            '#size' => 40,
            '#weight' => -1,
        );
    }
    
    /**
     * Provide default options for exposed sorts.
     */
    public function expose_options() {
        $this->options['expose'] = array(
            'order' => $this->options['order'],
            'label' => $this->definition['title'],
        );
    }

}