Add a HTML renderer for Icinga\Web\Menu

The menu was being rendered through recursive partials before. The
overhead this fact implicates is not as efficient as standard recursion
so there is now a special renderer for Icinga\Web\Menu utilizing
the RecursiveIteratorIterator

refs #6153

application/controllers/LayoutController.php

@@ -2,6 +2,7 @@
 // {{{ICINGA_LICENSE_HEADER}}}
 // {{{ICINGA_LICENSE_HEADER}}}
 
+use Icinga\Web\MenuRenderer;
 use Icinga\Web\Controller\ActionController;
 use Icinga\Web\Hook;
 use Icinga\Web\Menu;
@@ -17,9 +18,7 @@ class LayoutController extends ActionController
      */
     public function menuAction()
     {
-        $this->view->url    = Url::fromRequest()->getRelativeUrl();
+        $this->view->menuRenderer = new MenuRenderer(Menu::fromConfig()->order(), Url::fromRequest()->getRelativeUrl());
-        $this->view->items  = Menu::fromConfig()->getChildren();
-        $this->view->sub    = false;
     }
 
     /**

application/layouts/scripts/parts/menu.phtml

@@ -1,33 +0,0 @@
-<?php
-if (! $this->level) {
-    $this->level = 0;
-}
-?>
-<ul<?= $this->level === 0 ? ' role="navigation"' : '' ?>>
-<?php
-
-foreach ($this->items as $item) {
-
-    printf(
-        '  <li%s><a href="%s">%s%s</a>',
-        $this->href($this->url) === $this->href($item->getUrl()) ? ' class="active"' : '',
-        $item->getUrl() ? $this->href($item->getUrl()) : '#',
-        $item->getIcon() ? $this->img(
-            $item->getIcon(),
-            array('class' => 'icon')
-        ) . ' ' : '',
-        $this->escape($item->getTitle())
-    );
-
-    if ($item->hasChildren()) {
-        echo $this->partial(
-            'parts/menu.phtml',
-            array('items' => $item->getChildren(), 'url' => $this->url, 'level' => $this->level + 1)
-        );
-    }
-
-    echo "</li>\n";
-}
-
-?>
-</ul>

application/layouts/scripts/parts/navigation.phtml

@@ -2,22 +2,17 @@
 
 use Icinga\Web\Url;
 use Icinga\Web\Menu;
+use Icinga\Web\MenuRenderer;
 
 // Don't render a menu for unauthenticated users unless menu is auth aware
 if (! $this->auth()->isAuthenticated()) {
     return;
 }
 
-// Current url
-$url = Url::fromRequest()->getRelativeUrl();
-$menu = Menu::fromConfig();
 ?>
 <div id="menu" data-base-target="_main">
   <form action="<?= $this->href('search') ?>" method="get" role="search">
     <input type="text" name="q" class="search autofocus" placeholder="<?= $this->translate('Search...') ?>" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false" />
   </form>
-<?= $this->partial('parts/menu.phtml', array(
+<?= new MenuRenderer(Menu::fromConfig()->order(), Url::fromRequest()->getRelativeUrl()); ?>
-    'items' => $menu->getChildren(),
-    'url'   => $url
-)) ?>
 </div>

application/views/scripts/layout/menu.phtml

@@ -1,39 +1 @@
-<ul>
+<?= $menuRenderer; ?>
-    <?php foreach ($items as $item): ?>
-        <?php
-        $itemClass = '';
-        if ($sub) {
-            // $itemClass .= 'submenu ';
-        }
-        if ($this->href($url) === $this->href($item->getUrl())) {
-            $itemClass .= 'active ';
-        }
-        ?>
-        <li <?php if (!empty($itemClass)): ?>class="<?= $itemClass ?>"<?php endif ?>>
-            <?php if($item->getUrl()): ?>
-                <a href="<?= $this->href($item->getUrl()); ?>" <?php foreach($item->getAttribs() as $attrib => $value): ?> <?= $attrib ?>="<?= $value ?>"<?php endforeach?>>
-            <?php endif; ?>
-            <?php
-            if ($icon = $item->getIcon()) {
-                echo $this->img($icon, array('height' => 16, 'width' => 16));
-            }
-            ?>
-            <?php if ($iconClass = $item->getIconClass()): ?>
-            <i class="<?= $iconClass ?>"></i>
-            <?php endif ?>
-            <?= $item->getTitle();?>
-            <?php if($item->getUrl()): ?>
-                </a>
-            <?php endif; ?>
-            <?php
-            if($item->hasChildren()) {
-                echo $this->partial(
-                    'layout/menu.phtml',
-                    'default',
-                    array('items' => $item->getChildren(), 'sub' => true, 'url' => $this->url)
-                );
-            }
-            ?>
-        </li>
-    <?php endforeach ?>
-</ul>

library/Icinga/Web/MenuRenderer.php

@@ -0,0 +1,151 @@
+<?php
+// {{{ICINGA_LICENSE_HEADER}}}
+// {{{ICINGA_LICENSE_HEADER}}}
+
+namespace Icinga\Web;
+
+use RecursiveIteratorIterator;
+
+/**
+ * A renderer to draw a menu with its sub-menus using an unordered html list
+ */
+class MenuRenderer extends RecursiveIteratorIterator
+{
+    /**
+     * The relative url of the current request
+     *
+     * @var string
+     */
+    protected $url;
+
+    /**
+     * The html tags to assemble the menu with
+     *
+     * @var array
+     */
+    protected $tags = array();
+
+    /**
+     * Create a new MenuRenderer
+     *
+     * @param   Menu    $menu   The menu to render
+     * @param   string  $url    A relative url to identify "active" children with
+     */
+    public function __construct(Menu $menu, $url = null)
+    {
+        $this->url = $url;
+        parent::__construct($menu, RecursiveIteratorIterator::CHILD_FIRST);
+    }
+
+    /**
+     * Register the outer ul opening html-tag
+     */
+    public function beginIteration()
+    {
+        $this->tags[] = '<ul role="navigation">';
+    }
+
+    /**
+     * Register the outer ul closing html-tag
+     */
+    public function endIteration()
+    {
+        $this->tags[] = '</ul>';
+    }
+
+    /**
+     * Register a inner ul opening html-tag
+     */
+    public function beginChildren()
+    {
+        // The iterator runs in mode CHILD_FIRST so we need to remember
+        // where to insert the parent's opening html tag once its rendered
+        $parent = $this->getSubIterator(0)->current();
+        $this->tags[$parent->getId() . '_begin'] = null;
+
+        $this->tags[] = '<ul>';
+    }
+
+    /**
+     * Register a inner ul closing html-tag
+     */
+    public function endChildren()
+    {
+        $this->tags[] = '</ul>';
+
+        // Remember the position of the parent's closing html-tag
+        $parent = $this->getSubIterator(0)->current();
+        $this->tags[$parent->getId() . '_end'] = null;
+    }
+
+    /**
+     * Render the given child
+     *
+     * @param   Menu    $child      The menu's child to render
+     *
+     * @return  string              The child rendered as html
+     */
+    public function renderChild(Menu $child)
+    {
+        return sprintf(
+            '<a href="%s">%s%s</a>',
+            $child->getUrl() ? Url::fromPath($child->getUrl()) : '#',
+            $child->getIcon() ? '<img src="' . Url::fromPath($child->getIcon()) . '" class="icon" /> ' : '',
+            htmlspecialchars($child->getTitle())
+        );
+    }
+
+    /**
+     * Return the menu rendered as html
+     *
+     * @return  string
+     */
+    public function render()
+    {
+        $passedActiveChild = false;
+        foreach ($this as $child) {
+            $childIsActive = $this->isActive($child);
+            if ($childIsActive && $this->getDepth() > 0) {
+                $passedActiveChild = true;
+            }
+
+            if ($childIsActive || ($passedActiveChild && $this->getDepth() === 0)) {
+                $passedActiveChild &= $this->getDepth() !== 0;
+                $openTag = '<li class="active">';
+            } else {
+                $openTag = '<li>';
+            }
+            $content = $this->renderChild($child);
+            $closingTag = '</li>';
+
+            if (array_key_exists($child->getId() . '_begin', $this->tags)) {
+                $this->tags[$child->getId() . '_begin'] = $openTag . $content;
+                $this->tags[$child->getId() . '_end'] = $closingTag;
+            } else {
+                $this->tags[] = $openTag . $content . $closingTag;
+            }
+        }
+
+        return implode("\n", $this->tags);
+    }
+
+    /**
+     * @see MenuRenderer::render()
+     */
+    public function __toString()
+    {
+        return $this->render();
+    }
+
+    /**
+     * Return whether the current request url references the child's url
+     *
+     * @param   Menu    $child      The menu's child to check
+     *
+     * @return  bool
+     */
+    protected function isActive(Menu $child)
+    {
+        return html_entity_decode(rawurldecode($this->url)) === html_entity_decode(rawurldecode($child->getUrl()));
+    }
+}