lib: Add navigation classes (WIP)

- Lacks custom renderer functionality
- Lacks navigation item priorities
- Lacks permission handling

refs #5600

library/Icinga/Web/Navigation/DropdownItem.php

@@ -0,0 +1,21 @@
+<?php
+/* Icinga Web 2 | (c) 2013-2015 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Navigation;
+
+/**
+ * Dropdown navigation item
+ *
+ * @see \Icinga\Web\Navigation\Navigation For a usage example.
+ */
+class DropdownItem extends NavigationItem
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function init()
+    {
+        $this->children->setLayout(Navigation::LAYOUT_DROPDOWN);
+    }
+}
+

library/Icinga/Web/Navigation/Navigation.php

@@ -0,0 +1,235 @@
+<?php
+/* Icinga Web 2 | (c) 2013-2015 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Navigation;
+
+use ArrayAccess;
+use ArrayIterator;
+use Countable;
+use InvalidArgumentException;
+use IteratorAggregate;
+
+/**
+ * Container for navigation items
+ *
+ * Usage example:
+ * <code>
+ * <?php
+ *
+ * namespace Icinga\Example;
+ *
+ * use Icinga\Web\Navigation\DropdownItem;
+ * use Icinga\Web\Navigation\Navigation;
+ * use Icinga\Web\Navigation\NavigationItem;
+ *
+ * $navigation = new Navigation();
+ * $navigation->setLayout(Navigation::LAYOUT_TABS);
+ * $home = new NavigationItem();
+ * $home
+ *     ->setIcon('home')
+ *     ->setLabel('Home');
+ *     ->setUrl('/home');
+ * $logout = new NavigationItem();
+ * $logout
+ *     ->setIcon('logout')
+ *     ->setLabel('Logout')
+ *     ->setUrl('/logout');
+ * $dropdown = new DropdownItem();
+ * $dropdown
+ *     ->setIcon('user')
+ *     ->setLabel('Preferences');
+ * $preferences = new NavigationItem();
+ * $preferences
+ *     ->setIcon('preferences');
+ *     ->setLabel('preferences')
+ *     ->setUrl('/preferences');
+ * $dropdown->addChild($preferences);
+ * $navigation
+ *     ->addItem($home)
+ *     ->addItem($logout);
+ *     ->addItem($dropdown);
+ * echo $navigation
+ *     ->getRenderer()
+ *     ->setCssClass('example-nav')
+ *     ->render();
+ */
+class Navigation implements ArrayAccess, Countable, IteratorAggregate
+{
+    /**
+     * Flag for dropdown layout
+     *
+     * @var int
+     */
+    const LAYOUT_DROPDOWN = 1;
+
+    /**
+     * Flag for tabs layout
+     *
+     * @var int
+     */
+    const LAYOUT_TABS = 2;
+
+    /**
+     * Navigation items
+     *
+     * @var NavigationItem[]
+     */
+    protected $items = array();
+
+    /**
+     * Navigation layout
+     *
+     * @var int
+     */
+    protected $layout;
+
+    /**
+     * {@inheritdoc}
+     */
+    public function offsetExists($offset)
+    {
+        return isset($this->items[$offset]);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function offsetGet($offset)
+    {
+        return isset($this->items[$offset]) ? $this->items[$offset] : null;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function offsetSet($offset, $value)
+    {
+        $this->items[$offset] = $value;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function offsetUnset($offset)
+    {
+        unset($this->items[$offset]);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function count()
+    {
+        return count($this->items);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getIterator()
+    {
+        return new ArrayIterator($this->items);
+    }
+
+    /**
+     * Ad a navigation item
+     *
+     * @param   NavigationItem|array    $item   The item to append
+     *
+     * @return  $this
+     * @throws  InvalidArgumentException        If the item argument is invalid
+     */
+    public function addItem(NavigationItem $item)
+    {
+        if (! $item instanceof NavigationItem) {
+            if (! is_array($item)) {
+                throw new InvalidArgumentException(
+                    'Argument item must be either an array or an instance of NavigationItem'
+                );
+            }
+            $item = new NavigationItem($item);
+        }
+        $this->items[] = $item;
+        return $this;
+    }
+
+    /**
+     * Get the item with the given ID
+     *
+     * @param   mixed   $id
+     * @param   mixed   $default
+     *
+     * @return  NavigationItem|mixed
+     */
+    public function getItem($id, $default = null)
+    {
+        if (isset($this->items[$id])) {
+            return $this->items[$id];
+        }
+        return $default;
+    }
+
+    /**
+     * Get the items
+     *
+     * @return array
+     */
+    public function getItems()
+    {
+        return $this->items;
+    }
+
+    /**
+     * Get whether the navigation has items
+     *
+     * @return bool
+     */
+    public function hasItems()
+    {
+        return ! empty($this->items);
+    }
+
+    /**
+     * Get whether the navigation is empty
+     *
+     * @return bool
+     */
+    public function isEmpty()
+    {
+        return empty($this->items);
+    }
+
+    /**
+     * Get the layout
+     *
+     * @return int
+     */
+    public function getLayout()
+    {
+        return $this->layout;
+    }
+
+    /**
+     * Set the layout
+     *
+     * @param   int $layout
+     *
+     * @return  $this
+     */
+    public function setLayout($layout)
+    {
+        $this->layout = (int) $layout;
+        return $this;
+    }
+
+    /**
+     * Get the navigation renderer
+     *
+     * @return RecursiveNavigationRenderer
+     */
+    public function getRenderer()
+    {
+        return new RecursiveNavigationRenderer($this);
+    }
+}
+

library/Icinga/Web/Navigation/NavigationItem.php

@@ -0,0 +1,483 @@
+<?php
+/* Icinga Web 2 | (c) 2013-2015 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Navigation;
+
+use Countable;
+use InvalidArgumentException;
+use IteratorAggregate;
+use Icinga\Application\Icinga;
+use Icinga\Web\View;
+use Icinga\Web\Url;
+
+/**
+ * A navigation item
+ *
+ * @see \Icinga\Web\Navigation\Navigation For a usage example.
+ */
+class NavigationItem implements Countable, IteratorAggregate
+{
+    /**
+     * Alternative markup element if the navigation item has no URL
+     *
+     * @var string
+     */
+    const LINK_ALTERNATIVE = 'span';
+
+    /**
+     * Whether the item is active
+     *
+     * @var bool
+     */
+    protected $active = false;
+
+    /**
+     * Attributes of the item's element
+     *
+     * @var array
+     */
+    protected $attributes = array();
+
+    /**
+     * Item's children
+     *
+     * @var Navigation
+     */
+    protected $children;
+
+    /**
+     * Icon
+     *
+     * @var string|null
+     */
+    protected $icon;
+
+    /**
+     * Item's ID
+     *
+     * @var mixed
+     */
+    protected $id;
+
+    /**
+     * Label
+     *
+     * @var string|null
+     */
+    protected $label;
+
+    /**
+     * Parent
+     *
+     * @var NavigationItem|null
+     */
+    private $parent;
+
+    /**
+     * URL
+     *
+     * @var Url|null
+     */
+    protected $url;
+
+    /**
+     * URL parameters
+     *
+     * @var array
+     */
+    protected $urlParameters = array();
+
+    /**
+     * View
+     *
+     * @var View|null
+     */
+    protected $view;
+
+    /**
+     * Create a new navigation item
+     *
+     * @param array $properties
+     */
+    public function __construct(array $properties = array())
+    {
+        if (! empty($properties)) {
+            $this->setProperties($properties);
+        }
+        $this->children = new Navigation();
+        $this->init();
+    }
+
+    /**
+     * Initialize the navigation item
+     */
+    public function init()
+    {
+
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function count()
+    {
+        return $this->children->count();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getIterator()
+    {
+        return $this->children;
+    }
+
+    /**
+     * Get whether the item is active
+     *
+     * @return bool
+     */
+    public function getActive()
+    {
+        return $this->active;
+    }
+
+    /**
+     * Set whether the item is active
+     *
+     * Bubbles active state.
+     *
+     * @param   bool    $active
+     *
+     * @return  $this
+     */
+    public function setActive($active = true)
+    {
+        $this->active = (bool) $active;
+        $parent = $this;
+        while (($parent = $parent->parent) !== null) {
+            $parent->setActive($active);
+        }
+        return $this;
+    }
+
+    /**
+     * Get an attribute's value of the item's element
+     *
+     * @param   string      $name       Name of the attribute
+     * @param   mixed       $default    Default value
+     *
+     * @return  mixed
+     */
+    public function getAttribute($name, $default = null)
+    {
+        $name = (string) $name;
+        if (array_key_exists($name, $this->attributes)) {
+            return $this->attributes[$name];
+        }
+        return $default;
+    }
+
+    /**
+     * Set an attribute of the item's element
+     *
+     * @param   string  $name   Name of the attribute
+     * @param   mixed   $value  Value of the attribute
+     *
+     * @return  $this
+     */
+    public function setAttribute($name, $value)
+    {
+        $name = (string) $name;
+        $this->attributes[$name] = $value;
+        return $this;
+    }
+
+    /**
+     * Get the item's attributes
+     *
+     * @return array
+     */
+    public function getAttributes()
+    {
+        return $this->attributes;
+    }
+
+    /**
+     * Set the item's attributes
+     *
+     * @param   array   $attributes
+     *
+     * @return  $this
+     */
+    public function setAttributes(array $attributes)
+    {
+        foreach ($attributes as $name => $value) {
+            $this->setAttribute($name, $value);
+        }
+        return $this;
+    }
+
+    /**
+     * Add a child item to this item
+     *
+     * Bubbles active state.
+     *
+     * @param   NavigationItem|array    $child  The child to add
+     *
+     * @return  $this
+     * @throws  InvalidArgumentException        If the child argument is invalid
+     */
+    public function addChild($child)
+    {
+        if (! $child instanceof NavigationItem) {
+            if (! is_array($child)) {
+                throw new InvalidArgumentException(
+                    'Argument child must be either an array or an instance of NavigationItem'
+                );
+            }
+            $child = new NavigationItem($child);
+        }
+        $child->parent = $this;
+        $this->children->addItem($child);
+        if ($child->getActive()) {
+            $this->setActive();
+        }
+        return $this;
+    }
+
+    /**
+     * Get the item's children
+     *
+     * @return Navigation
+     */
+    public function getChildren()
+    {
+        return $this->children;
+    }
+
+    /**
+     * Get whether the item has children
+     *
+     * @return bool
+     */
+    public function hasChildren()
+    {
+        return ! $this->children->isEmpty();
+    }
+
+    /**
+     * Set children
+     *
+     * @param   Navigation  $children
+     *
+     * @return  $this
+     */
+    public function setChildren(Navigation $children)
+    {
+        $this->children = $children;
+        return $this;
+    }
+
+    /**
+     * Get the icon
+     *
+     * @return string|null
+     */
+    public function getIcon()
+    {
+        return $this->icon;
+    }
+
+    /**
+     * Set the icon
+     *
+     * @param   string  $icon
+     *
+     * @return  $this
+     */
+    public function setIcon($icon)
+    {
+        $this->icon = (string) $icon;
+        return $this;
+    }
+
+    /**
+     * Get the item's ID
+     *
+     * @return mixed
+     */
+    public function getId()
+    {
+        return $this->id;
+    }
+
+    /**
+     * Set the item's ID
+     *
+     * @param   mixed   $id ID of the item
+     *
+     * @return  $this
+     */
+    public function setId($id)
+    {
+        $this->id = $id;
+        return $this;
+    }
+
+    /**
+     * Get the label
+     *
+     * @return string|null
+     */
+    public function getLabel()
+    {
+        return $this->label;
+    }
+
+    /**
+     * Set the label
+     *
+     * @param   string  $label
+     *
+     * @return  $this
+     */
+    public function setLabel($label)
+    {
+        $this->label = (string) $label;
+        return $this;
+    }
+
+    /**
+     * Get the URL
+     *
+     * @return Url|null
+     */
+    public function getUrl()
+    {
+        if ($this->url !== null && ! $this->url instanceof Url) {
+            $this->url = Url::fromPath((string) $this->url);
+        }
+        return $this->url;
+    }
+
+    /**
+     * Set the URL
+     *
+     * @param   Url|string $url
+     *
+     * @return  $this
+     */
+    public function setUrl($url)
+    {
+        $this->url = $url;
+        return $this;
+    }
+
+    /**
+     * Get the URL parameters
+     *
+     * @return array
+     */
+    public function getUrlParameters()
+    {
+        return $this->urlParameters;
+    }
+
+    /**
+     * Set the URL parameters
+     *
+     * @param   array   $urlParameters
+     *
+     * @return  $this
+     */
+    public function setUrlParameters(array $urlParameters)
+    {
+        $this->urlParameters = $urlParameters;
+        return $this;
+    }
+
+    /**
+     * Get the view
+     *
+     * @return View
+     */
+    public function getView()
+    {
+        if ($this->view === null) {
+            $this->view = Icinga::app()->getViewRenderer()->view;
+        }
+        return $this->view;
+    }
+
+    /**
+     * Set the view
+     *
+     * @param   View    $view
+     *
+     * @return  $this
+     */
+    public function setView(View $view)
+    {
+        $this->view = $view;
+        return $this;
+    }
+
+    /**
+     * Set properties for the item
+     *
+     * @param   array   $properties
+     *
+     * @return  $this
+     */
+    public function setProperties(array $properties = array())
+    {
+        foreach ($properties as $name => $value) {
+            $setter = 'set' . ucfirst($name);
+            if (method_exists($this, $setter)) {
+                $this->$setter($value);
+            }
+        }
+        return $this;
+    }
+
+    /**
+     * Render the navigation item to HTML
+     *
+     * @return string
+     */
+    public function render()
+    {
+        $view = $this->getView();
+        $label = $view->escape($this->getLabel());
+        if (null !== $icon = $this->getIcon()) {
+            $label = $view->icon($icon) . $label;
+        }
+        if (null !== $url = $this->getUrl()) {
+            $content = sprintf(
+                '<a%s href="%s">%s</a>',
+                $view->propertiesToString($this->getAttributes()),
+                $view->url($url, $this->getUrlParameters()),
+                $label
+            );
+        } else {
+            $content = sprintf(
+                '<%1$s%2$s>%3$s</%1$s>',
+                static::LINK_ALTERNATIVE,
+                $view->propertiesToString($this->getAttributes()),
+                $label
+            );
+        }
+        return $content;
+    }
+
+    /**
+     * Render the navigation item to HTML
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->render();
+    }
+}

library/Icinga/Web/Navigation/NavigationRenderer.php

@@ -0,0 +1,340 @@
+<?php
+/* Icinga Web 2 | (c) 2013-2015 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Navigation;
+
+use ArrayIterator;
+use RecursiveIterator;
+use Icinga\Application\Icinga;
+use Icinga\Web\View;
+
+/**
+ * Renderer for single level navigation
+ */
+class NavigationRenderer implements RecursiveIterator, NavigationRendererInterface
+{
+    /**
+     * Content to render
+     *
+     * @var array
+     */
+    private $content = array();
+
+    /**
+     * CSS class for the navigation element
+     *
+     * @var string|null
+     */
+    protected $cssClass;
+
+    /**
+     * Flags
+     *
+     * @var int
+     */
+    private $flags;
+
+    /**
+     * The heading for the navigation
+     *
+     * @var string
+     */
+    protected $heading;
+
+    /**
+     * Flag for checking whether to call begin/endMarkup() or not
+     *7
+     * @var bool
+     */
+    private $inIteration = false;
+
+    /**
+     * Iterator over navigation
+     *
+     * @var ArrayIterator
+     */
+    private $iterator;
+
+    /**
+     * Current navigation
+     *
+     * @var Navigation
+     */
+    private $navigation;
+
+    /**
+     * View
+     *
+     * @var View|null
+     */
+    protected $view;
+
+    /**
+     * Create a new navigation renderer
+     *
+     * @param   Navigation      $navigation
+     * @param   int             $flags
+     */
+    public function __construct(Navigation $navigation, $flags = 0)
+    {
+        $this->iterator = $navigation->getIterator();
+        $this->navigation = $navigation;
+        $this->flags = $flags;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getChildren()
+    {
+        return new static($this->current()->getChildren(), $this->flags & static::NAV_DISABLE);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function hasChildren()
+    {
+        return $this->current()->hasChildren();
+    }
+
+    /**
+     * {@inheritdoc}
+     * @return \Icinga\Web\Navigation\NavigationItem
+     */
+    public function current()
+    {
+        return $this->iterator->current();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function key()
+    {
+        return $this->iterator->key();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function next()
+    {
+        $this->iterator->next();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function rewind()
+    {
+        $this->iterator->rewind();
+        if (! (bool) ($this->flags & static::NAV_DISABLE) && ! $this->inIteration) {
+            $this->content[] = $this->beginMarkup();
+            $this->inIteration = true;
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function valid()
+    {
+        $valid = $this->iterator->valid();
+        if (! (bool) ($this->flags & static::NAV_DISABLE) && ! $valid && $this->inIteration) {
+            $this->content[] = $this->endMarkup();
+            $this->inIteration = false;
+        }
+        return $valid;
+    }
+
+    /**
+     * Begin navigation markup
+     *
+     * @return string
+     */
+    public function beginMarkup()
+    {
+        $content = array();
+        if ($this->flags & static::NAV_MAJOR) {
+            $el = 'nav';
+        } else {
+            $el = 'div';
+        }
+        if (($elCssClass = $this->getCssClass()) !== null) {
+            $elCss = ' class="' . $elCssClass . '"';
+        } else {
+            $elCss = '';
+        }
+        $content[] = sprintf(
+            '<%s%s role="navigation">',
+            $el,
+            $elCss
+        );
+        $content[] = sprintf(
+            '<h%1$d class="sr-only" tabindex="-1">%2$s</h%1$d>',
+            static::HEADING_RANK,
+            $this->getView()->escape($this->getHeading())
+        );
+        $content[] = $this->beginChildrenMarkup();
+        return implode("\n", $content);
+    }
+
+    /**
+     * End navigation markup
+     *
+     * @return string
+     */
+    public function endMarkup()
+    {
+        $content = array();
+        $content[] = $this->endChildrenMarkup();
+        if ($this->flags & static::NAV_MAJOR) {
+            $content[] = '</nav>';
+        } else {
+            $content[] = '</div>';
+        }
+        return implode("\n", $content);
+    }
+
+    /**
+     * Begin children markup
+     *
+     * @return string
+     */
+    public function beginChildrenMarkup()
+    {
+        $ulCssClass = static::CSS_CLASS_NAV;
+        if ($this->navigation->getLayout() & Navigation::LAYOUT_TABS) {
+            $ulCssClass .= ' ' . static::CSS_CLASS_NAV_TABS;
+        }
+        if ($this->navigation->getLayout() & Navigation::LAYOUT_DROPDOWN) {
+            $ulCssClass .= ' ' . static::CSS_CLASS_NAV_DROPDOWN;
+        }
+        return '<ul class="' . $ulCssClass . '">';
+    }
+
+    /**
+     * End children markup
+     *
+     * @return string
+     */
+    public function endChildrenMarkup()
+    {
+        return '</ul>';
+    }
+
+    /**
+     * Begin item markup
+     *
+     * @param   NavigationItem  $item
+     *
+     * @return  string
+     */
+    public function beginItemMarkup(NavigationItem $item)
+    {
+        $cssClass = array();
+        if ($item->getActive()) {
+            $cssClass[] = static::CSS_CLASS_ACTIVE;
+        }
+        if ($item->hasChildren()
+            && $item->getChildren()->getLayout() === Navigation::LAYOUT_DROPDOWN
+        ) {
+            $cssClass[] = static::CSS_CLASS_DROPDOWN;
+            $item
+                ->setAttribute('class', static::CSS_CLASS_DROPDOWN_TOGGLE)
+                ->setIcon(static::DROPDOWN_TOGGLE_ICON)
+                ->setUrl('#');
+        }
+        if (! empty($cssClass)) {
+            $content = sprintf('<li class="%s">', implode(' ', $cssClass));
+        } else {
+            $content = '<li>';
+        }
+        return $content;
+    }
+
+    /**
+     * End item markup
+     *
+     * @return string
+     */
+    public function endItemMarkup()
+    {
+        return '</li>';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getCssClass()
+    {
+        return $this->cssClass;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function setCssClass($class)
+    {
+        $this->cssClass = trim((string) $class);
+        return $this;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getHeading()
+    {
+        return $this->heading;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function setHeading($heading)
+    {
+        $this->heading = (string) $heading;
+        return $this;
+    }
+
+    /**
+     * Get the view
+     *
+     * @return View
+     */
+    public function getView()
+    {
+        if ($this->view === null) {
+            $this->view = Icinga::app()->getViewRenderer()->view;
+        }
+        return $this->view;
+    }
+
+    /**
+     * Set the view
+     *
+     * @param   View    $view
+     *
+     * @return  $this
+     */
+    public function setView(View $view)
+    {
+        $this->view = $view;
+        return $this;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function render()
+    {
+        foreach ($this as $navigationItem) {
+            /** @var \Icinga\Web\Navigation\NavigationItem $navigationItem */
+            $this->content[] = $this->beginItemMarkup($navigationItem);
+            $this->content[] = $navigationItem->render();
+            $this->content[] = $this->endItemMarkup();
+        }
+        return implode("\n", $this->content);
+    }
+}

library/Icinga/Web/Navigation/NavigationRendererInterface.php

@@ -0,0 +1,122 @@
+<?php
+/* Icinga Web 2 | (c) 2013-2015 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Navigation;
+
+use Icinga\Web\View;
+
+/**
+ * Interface for navigation renderer
+ */
+interface NavigationRendererInterface
+{
+    /**
+     * CSS class for active items
+     *
+     * @var string
+     */
+    const CSS_CLASS_ACTIVE = 'active';
+
+    /**
+     * CSS class for dropdown items
+     *
+     * @var string
+     */
+    const CSS_CLASS_DROPDOWN = 'dropdown';
+
+    /**
+     * CSS class for dropdown's trigger
+     */
+    const CSS_CLASS_DROPDOWN_TOGGLE = 'dropdown-toggle';
+
+    /**
+     * CSS class for the ul element
+     *
+     * @var string
+     */
+    const CSS_CLASS_NAV = 'nav';
+
+    /**
+     * CSS class for the ul element w/ dropdown layout
+     *
+     * @var string
+     */
+    const CSS_CLASS_NAV_DROPDOWN = 'dropdown-menu';
+
+    /**
+     * CSS class for the ul element w/ tabs layout
+     *
+     * @var string
+     */
+    const CSS_CLASS_NAV_TABS = 'nav-tabs';
+
+    /**
+     * Icon for the dropdown's trigger
+     *
+     * @var string
+     */
+    const DROPDOWN_TOGGLE_ICON = 'menu';
+
+    /**
+     * Heading rank
+     *
+     * @var int
+     */
+    const HEADING_RANK = 2;
+
+    /**
+     * Flag for major navigation
+     *
+     * With this flag the outer navigation element will be nav instead of div
+     *
+     * @var int
+     */
+    const NAV_MAJOR = 1;
+
+    /**
+     * Flag for disabling the outer navigation element
+     *
+     * @var int
+     */
+    const NAV_DISABLE = 2;
+
+    /**
+     * Get the CSS class for the outer element
+     *
+     * @return string|null
+     */
+    public function getCssClass();
+
+    /**
+     * Set the CSS class for the outer element
+     *
+     * @param   string  $class
+     *
+     * @return  $this
+     */
+    public function setCssClass($class);
+
+    /**
+     * Get the heading
+     *
+     * @return string
+     */
+    public function getHeading();
+
+    /**
+     * Set the heading
+     *
+     * @param   string  $heading
+     *
+     * @return  $this
+     */
+    public function setHeading($heading);
+
+    /**
+     * Render navigation to HTML
+     *
+     * @return string
+     */
+    public function render();
+}
+

library/Icinga/Web/Navigation/RecursiveNavigationRenderer.php

@@ -0,0 +1,118 @@
+<?php
+/* Icinga Web 2 | (c) 2013-2015 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Navigation;
+
+use RecursiveIteratorIterator;
+use Icinga\Web\View;
+
+/**
+ * Renderer for multi level navigation
+ *
+ * @method NavigationRenderer getInnerIterator() {
+ *     {@inheritdoc}
+ * }
+ */
+class RecursiveNavigationRenderer extends RecursiveIteratorIterator implements NavigationRendererInterface
+{
+    /**
+     * Content to render
+     *
+     * @var array
+     */
+    private $content = array();
+
+    /**
+     * Create a new recursive navigation renderer
+     *
+     * @param   Navigation  $navigation
+     * @param   int         $flags
+     */
+    public function __construct(Navigation $navigation, $flags = 0)
+    {
+        $navigationRenderer = new NavigationRenderer($navigation, $flags & static::NAV_DISABLE);
+        parent::__construct($navigationRenderer, RecursiveIteratorIterator::SELF_FIRST);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function beginIteration()
+    {
+        $this->content[] = $this->getInnerIterator()->beginMarkup();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function endIteration()
+    {
+        $this->content[] = $this->getInnerIterator()->endMarkup();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function beginChildren()
+    {
+        $this->content[] = $this->getInnerIterator()->beginChildrenMarkup();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function endChildren()
+    {
+        $this->content[] = $this->getInnerIterator()->endChildrenMarkup();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getCssClass()
+    {
+        return $this->getInnerIterator()->getCssClass();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function setCssClass($class)
+    {
+        $this->getInnerIterator()->setCssClass($class);
+        return $this;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getHeading()
+    {
+        return $this->getInnerIterator()->getHeading();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function setHeading($heading)
+    {
+        $this->getInnerIterator()->setHeading($heading);
+        return $this;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function render()
+    {
+        foreach ($this as $navigationItem) {
+            /** @var \Icinga\Web\Navigation\NavigationItem $navigationItem */
+            $this->content[] = $this->getInnerIterator()->beginItemMarkup($navigationItem);
+            $this->content[] = $navigationItem->render();
+            if (! $navigationItem->hasChildren()) {
+                $this->content[] = $this->getInnerIterator()->endItemMarkup();
+            }
+        }
+        return implode("\n", $this->content);
+    }
+}