Contao\ModuleBooknav::compile PHP Method

    protected function compile()
    {
        // Get the root page
        if (!($objTarget = $this->objModel->getRelated('rootPage')) instanceof PageModel) {
            return;
        }
        $groups = array();
        // Get all groups of the current front end user
        if (FE_USER_LOGGED_IN) {
            $this->import('FrontendUser', 'User');
            $groups = $this->User->groups;
        }
        // Get all book pages
        $this->arrPages[$objTarget->id] = $objTarget;
        $this->getBookPages($objTarget->id, $groups, time());
        /** @var PageModel $objPage */
        global $objPage;
        // Upper page
        if ($objPage->id != $objTarget->id) {
            $intKey = $objPage->pid;
            // Skip forward pages (see #5074)
            while ($this->arrPages[$intKey]->type == 'forward' && isset($this->arrPages[$intKey]->pid)) {
                $intKey = $this->arrPages[$intKey]->pid;
            }
            // Hide the link if the reference page is a forward page (see #5374)
            if (isset($this->arrPages[$intKey])) {
                $this->Template->hasUp = true;
                $this->Template->upHref = $this->arrPages[$intKey]->getFrontendUrl();
                $this->Template->upTitle = \StringUtil::specialchars($this->arrPages[$intKey]->title, true);
                $this->Template->upPageTitle = \StringUtil::specialchars($this->arrPages[$intKey]->pageTitle, true);
                $this->Template->upLink = $GLOBALS['TL_LANG']['MSC']['up'];
            }
        }
        $arrLookup = array_keys($this->arrPages);
        $intCurrent = array_search($objPage->id, $arrLookup);
        // HOOK: add pagination info
        $this->Template->currentPage = $intCurrent;
        $this->Template->pageCount = count($arrLookup);
        // Previous page
        if ($intCurrent > 0) {
            $current = $intCurrent;
            $intKey = $arrLookup[$current - 1];
            // Skip forward pages (see #5074)
            while ($this->arrPages[$intKey]->type == 'forward' && isset($arrLookup[--$current])) {
                $intKey = $arrLookup[$current - 1];
            }
            if ($intKey === null) {
                $this->Template->hasPrev = false;
            } else {
                $this->Template->hasPrev = true;
                $this->Template->prevHref = $this->arrPages[$intKey]->getFrontendUrl();
                $this->Template->prevTitle = \StringUtil::specialchars($this->arrPages[$intKey]->title, true);
                $this->Template->prevPageTitle = \StringUtil::specialchars($this->arrPages[$intKey]->pageTitle, true);
                $this->Template->prevLink = $this->arrPages[$intKey]->title;
            }
        }
        // Next page
        if ($intCurrent < count($arrLookup) - 1) {
            $current = $intCurrent;
            $intKey = $arrLookup[$current + 1];
            // Skip forward pages (see #5074)
            while ($this->arrPages[$intKey]->type == 'forward' && isset($arrLookup[++$current])) {
                $intKey = $arrLookup[$current + 1];
            }
            if ($intKey === null) {
                $this->Template->hasNext = false;
            } else {
                $this->Template->hasNext = true;
                $this->Template->nextHref = $this->arrPages[$intKey]->getFrontendUrl();
                $this->Template->nextTitle = \StringUtil::specialchars($this->arrPages[$intKey]->title, true);
                $this->Template->nextPageTitle = \StringUtil::specialchars($this->arrPages[$intKey]->pageTitle, true);
                $this->Template->nextLink = $this->arrPages[$intKey]->title;
            }
        }
    }