silverstripe-translatable/code/controller/TranslatableCMSMainExtension.php

<?php
/**
 * @package translatable
 */
class TranslatableCMSMainExtension extends Extension
{
    private static $allowed_actions = array(
        'createtranslation',
    );

    public function init()
    {
        $req = $this->owner->getRequest();
        
        // Ignore being called on LeftAndMain base class,
        // which is the case when requests are first routed through AdminRootController
        // as an intermediary rather than the endpoint controller
        if (!$this->owner->stat('tree_class')) {
            return;
        }

        // Locale" attribute is either explicitly added by LeftAndMain Javascript logic,
        // or implied on a translated record (see {@link Translatable->updateCMSFields()}).
        // $Lang serves as a "context" which can be inspected by Translatable - hence it
        // has the same name as the database property on Translatable.
        $id = $req->param('ID');
        if ($req->requestVar("Locale")) {
            $this->owner->Locale = $req->requestVar("Locale");
        } elseif ($id && is_numeric($id)) {
            $record = DataObject::get_by_id($this->owner->stat('tree_class'), $id);
            if ($record && $record->Locale) {
                $this->owner->Locale = $record->Locale;
            }
        } else {
            $this->owner->Locale = Translatable::default_locale();
            if ($this->owner->class == 'CMSPagesController') {
                // the CMSPagesController always needs to have the locale set, 
                // otherwise page editing will cause an extra
                // ajax request which looks weird due to multiple "loading"-flashes
                $getVars = $req->getVars();
                if (isset($getVars['url'])) {
                    unset($getVars['url']);
                }
                return $this->owner->redirect(Controller::join_links(
                    $this->owner->Link(),
                    $req->param('Action'),
                    $req->param('ID'),
                    $req->param('OtherID'),
                    ($query = http_build_query($getVars)) ? "?$query" : null
                ));
            }
        }
        Translatable::set_current_locale($this->owner->Locale);

        // If a locale is set, it needs to match to the current record
        $requestLocale = $req->requestVar("Locale");
        $page = $this->owner->currentPage();
        if (
            $req->httpMethod() == 'GET' // leave form submissions alone
            && $requestLocale
            && $page
            && $page->hasExtension('Translatable')
            && $page->Locale != $requestLocale
            && $req->latestParam('Action') != 'EditorToolbar'
        ) {
            $transPage = $page->getTranslation($requestLocale);
            if ($transPage) {
                Translatable::set_current_locale($transPage->Locale);
                return $this->owner->redirect(Controller::join_links(
                    $this->owner->Link('show'),
                    $transPage->ID
                    // ?locale will automatically be added
                ));
            } elseif ($this->owner->class != 'CMSPagesController') {
                // If the record is not translated, redirect to pages overview
                return $this->owner->redirect(Controller::join_links(
                    singleton('CMSPagesController')->Link(),
                    '?Locale=' . $requestLocale
                ));
            }
        }
        
        // collect languages for TinyMCE spellchecker plugin.
        // see http://wiki.moxiecode.com/index.php/TinyMCE:Plugins/spellchecker
        $langName = i18n::get_locale_name($this->owner->Locale);
        HtmlEditorConfig::get('cms')->setOption(
            'spellchecker_languages',
            "+{$langName}={$this->owner->Locale}"
        );

        Requirements::javascript('translatable/javascript/CMSMain.Translatable.js');
        Requirements::css('translatable/css/CMSMain.Translatable.css');
    }
    
    public function updateEditForm(&$form)
    {
        if ($form->getName() == 'RootForm' && SiteConfig::has_extension("Translatable")) {
            $siteConfig = SiteConfig::current_site_config();
            $form->Fields()->push(new HiddenField('Locale', '', $siteConfig->Locale));
        }
    }
    
    public function updatePageOptions(&$fields)
    {
        $fields->push(new HiddenField("Locale", 'Locale', Translatable::get_current_locale()));
    }
    
    /**
     * Create a new translation from an existing item, switch to this language and reload the tree.
     */
    public function createtranslation($data, $form)
    {
        $request = $this->owner->getRequest();

        // Protect against CSRF on destructive action
        if (!SecurityToken::inst()->checkRequest($request)) {
            return $this->owner->httpError(400);
        }

        $langCode = Convert::raw2sql($request->postVar('NewTransLang'));
        $record = $this->owner->getRecord($request->postVar('ID'));
        if (!$record) {
            return $this->owner->httpError(404);
        }
        
        $this->owner->Locale = $langCode;
        Translatable::set_current_locale($langCode);
        
        // Create a new record in the database - this is different
        // to the usual "create page" pattern of storing the record
        // in-memory until a "save" is performed by the user, mainly
        // to simplify things a bit.
        // @todo Allow in-memory creation of translations that don't 
        // persist in the database before the user requests it
        $translatedRecord = $record->createTranslation($langCode);

        $url = Controller::join_links(
            $this->owner->Link('show'),
            $translatedRecord->ID
        );

        // set the X-Pjax header to Content, so that the whole admin panel will be refreshed
        $this->owner->getResponse()->addHeader('X-Pjax', 'Content');
        
        return $this->owner->redirect($url);
    }

    public function updateLink(&$link)
    {
        $locale = $this->owner->Locale ? $this->owner->Locale : Translatable::get_current_locale();
        if ($locale) {
            $link = Controller::join_links($link, '?Locale=' . $locale);
        }
    }

    public function updateLinkWithSearch(&$link)
    {
        $locale = $this->owner->Locale ? $this->owner->Locale : Translatable::get_current_locale();
        if ($locale) {
            $link = Controller::join_links($link, '?Locale=' . $locale);
        }
    }

    public function updateExtraTreeTools(&$html)
    {
        $locale = $this->owner->Locale ? $this->owner->Locale : Translatable::get_current_locale();
        $html = $this->LangForm()->forTemplate() . $html;
    }

    public function updateLinkPageAdd(&$link)
    {
        $locale = $this->owner->Locale ? $this->owner->Locale : Translatable::get_current_locale();
        if ($locale) {
            $link = Controller::join_links($link, '?Locale=' . $locale);
        }
    }
    
    /**
     * Returns a form with all languages with languages already used appearing first.
     * 
     * @return Form
     */
    public function LangForm()
    {
        $member = Member::currentUser(); //check to see if the current user can switch langs or not
        if (Permission::checkMember($member, 'VIEW_LANGS')) {
            $field = new LanguageDropdownField(
                'Locale',
                _t('CMSMain.LANGUAGEDROPDOWNLABEL', 'Language'),
                array(),
                'SiteTree',
                'Locale-English',
                singleton('SiteTree')
            );
            $field->setValue(Translatable::get_current_locale());
        } else {
            // user doesn't have permission to switch langs 
            // so just show a string displaying current language
            $field = new LiteralField(
                'Locale',
                i18n::get_locale_name(Translatable::get_current_locale())
            );
        }
        
        $form = new Form(
            $this->owner,
            'LangForm',
            new FieldList(
                $field
            ),
            new FieldList(
                new FormAction('selectlang', _t('CMSMain_left.GO', 'Go'))
            )
        );
        $form->unsetValidator();
        $form->addExtraClass('nostyle');
        
        return $form;
    }
    
    public function selectlang($data, $form)
    {
        return $this->owner;
    }
    
    /**
     * Determine if there are more than one languages in our site tree.
     * 
     * @return boolean
     */
    public function MultipleLanguages()
    {
        $langs = Translatable::get_existing_content_languages('SiteTree');

        return (count($langs) > 1);
    }
    
    /**
     * @return boolean
     */
    public function IsTranslatableEnabled()
    {
        return SiteTree::has_extension('Translatable');
    }
}