Refs #2320 added new menu functions and classes

git-svn-id: http://code.elgg.org/elgg/trunk@7655 36083f99-b078-4883-b0ff-0f9b5a30f544

1 files changed, 249 insertions, 0 deletions

diff --git a/engine/classes/ElggMenuBuilder.php b/engine/classes/ElggMenuBuilder.php
new file mode 100644
index 000000000..b57ea6e18
--- /dev/null
+++ b/engine/classes/ElggMenuBuilder.php
@@ -0,0 +1,249 @@
+<?php
+/**
+ * Elgg Menu Builder
+ *
+ * @package    Elgg.Core
+ * @subpackage Navigation
+ *
+ * @since 1.8.0
+ */
+class ElggMenuBuilder {
+
+	protected $menu = array();
+
+	protected $selected = null;
+
+	/**
+	 * ElggMenuBuilder constructor
+	 *
+	 * @param string $name  Identifier of the menu
+	 */
+	public function __construct($name) {
+		global $CONFIG;
+
+		$this->menu = $CONFIG->menus[$name];
+	}
+
+	/**
+	 * Get a prepared menu array
+	 *
+	 * @param mixed $sort_by
+	 * @return array
+	 */
+	public function getMenu($sort_by) {
+
+		$this->selectFromContext();
+
+		$selected = $this->findSelected();
+
+		$this->setupSections();
+
+		$this->setupTrees();
+
+		$this->sort($sort_by);
+
+		return $this->menu;
+	}
+
+	/**
+	 * Get the selected menu item
+	 *
+	 * @return ElggMenuItem
+	 */
+	public function getSelected() {
+		return $this->selected;
+	}
+
+	/**
+	 * Select menu items for the current context
+	 *
+	 * @return void
+	 */
+	protected function selectFromContext() {
+		if (!isset($this->menu)) {
+			$this->menu = array();
+			return;
+		}
+
+		// get menu items for this context
+		$selected_menu = array();
+		foreach ($this->menu as $menu_item) {
+			if ($menu_item->inContext()) {
+				$selected_menu[] = $menu_item;
+			}
+		}
+
+		$this->menu = $selected_menu;
+	}
+
+	/**
+	 * Group the menu items into sections
+	 * @return void
+	 */
+	protected function setupSections() {
+		$sectioned_menu = array();
+		foreach ($this->menu as $menu_item) {
+			if (!isset($sectioned_menu[$menu_item->getSection()])) {
+				$sectioned_menu[$menu_item->getSection()] = array();
+			}
+			$sectioned_menu[$menu_item->getSection()][] = $menu_item;
+		}
+		$this->menu = $sectioned_menu;
+	}
+
+	/**
+	 * Create trees for each menu section
+	 *
+	 * @internal The tree is doubly linked (parent and children links)
+	 * @return void
+	 */
+	protected function setupTrees() {
+		$menu_tree = array();
+
+		foreach ($this->menu as $key => $section) {
+			$parents = array();
+			$children = array();
+			// divide base nodes from children
+			foreach ($section as $menu_item) {
+				$parent_name = $menu_item->getParentName();
+				if (!$parent_name) {
+					$parents[$menu_item->getName()] = $menu_item;
+				} else {
+					$children[] = $menu_item;
+				}
+			}
+
+			// attach children to parents
+			$iteration = 0;
+			$current_gen = $parents;
+			while (count($children) && $iteration < 5) {
+				foreach ($children as $index => $menu_item) {
+					$parent_name = $menu_item->getParentName();
+					if (array_key_exists($parent_name, $current_gen)) {
+						$next_gen[$menu_item->getName()] = $menu_item;
+						$current_gen[$parent_name]->addChild($menu_item);
+						$menu_item->setParent($current_gen[$parent_name]);
+						unset($children[$index]);
+					}
+				}
+				$current_gen = $next_gen;
+				$iteration += 1;
+			}
+
+			// convert keys to indexes for first level of tree
+			$parents = array_values($parents);
+
+			$menu_tree[$key] = $parents;
+		}
+
+		$this->menu = $menu_tree;
+	}
+
+	/**
+	 * Find the menu item that is currently selected
+	 *
+	 * @return ElggMenuItem
+	 */
+	protected function findSelected() {
+
+		// do we have a selected menu item already
+		foreach ($this->menu as $menu_item) {
+			if ($menu_item->getSelected()) {
+				return $menu_item;
+			}
+		}
+
+		// scan looking for a selected item
+		foreach ($this->menu as $menu_item) {
+			if ($menu_item->getURL()) {
+				if (elgg_http_url_is_identical(full_url(), $menu_item->getURL())) {
+					$menu_item->setSelected(true);
+					return $menu_item;
+				}
+			}
+		}
+
+		return null;
+	}
+
+	/**
+	 * Sort the menu sections and trees
+	 *
+	 * @param mixed $sort_by Sort type as string or php callback
+	 * @return void
+	 */
+	protected function sort($sort_by) {
+
+		// sort sections
+		ksort($this->menu);
+
+		switch ($sort_by) {
+			case 'title':
+				$sort_callback = array('ElggMenuBuilder', 'compareByTitle');
+				break;
+			case 'name';
+				$sort_callback = array('ElggMenuBuilder', 'compareByName');
+				break;
+			case 'order':
+				// use registration order
+				return;
+				break;
+			default:
+				if (is_callable($sort_by)) {
+					$sort_callback = $sort_by;
+				} else {
+					return;
+				}
+				break;
+		}
+
+		// sort each section
+		foreach ($this->menu as $index => $section) {
+			usort($section, $sort_callback);
+			$this->menu[$index] = $section;
+
+			// depth first traversal of tree
+			foreach ($section as $root) {
+				$stack = array();
+				array_push($stack, $root);
+				while (!empty($stack)) {
+					$node = array_pop($stack);
+					$node->sortChildren($sort_callback);
+					$children = $node->getChildren();
+					if ($children) {
+						$stack = array_merge($stack, $children);
+					}
+					$p = count($stack);
+				}
+			}
+		}
+	}
+
+	/**
+	 * Compare two menu items by their titles
+	 *
+	 * @param ElggMenuItem $a
+	 * @param ElggMenuItem $b
+	 * @return bool
+	 */
+	public static function compareByTitle($a, $b) {
+		$a = $a->getTitle();
+		$b = $b->getTitle();
+
+		return strnatcmp($a, $b);
+	}
+
+	/**
+	 * Compare two menu items by their identifiers
+	 *
+	 * @param ElggMenuItem $a
+	 * @param ElggMenuItem $b
+	 * @return bool
+	 */
+	public static function compareByName($a, $b) {
+		$a = $a->getName();
+		$b = $b->getName();
+
+		return strcmp($a, $b);
+	}
+}