<?php
/**
 * Menu Digger
 *
 * $Id$
 *
 * @author gERD Schaufelberger <gerd@php-tools.net>
 * @license PHP License
 * @package WB
 * @subpackage db
 */

WBClass::load('WBUser');

/**
 * Menu Digger
 *
 * @version 0.1.0
 * @package WB
 * @subpackage menu
 */
class WBDatasource_MenuDigger extends WBStdClass
{
    /**
     * Tree Menu to dig
     * @var WBDatasource_TreeMenu
     */
    private $treeMenu;

    /**
     * URL Dict
     * @var WBDictionary_URL
     */
    private $url;

    /**
     * List of URLs to ignore
     * @var array
     */
    private $ignore =   array();

    /**
     * maximum levels to dig down
     * @var int
     */
    private $maxLevel = -1;

    /**
     * List of callback listener
     *
     * @var array<WBDatasource_MenuDigger_Listener>
     */
    private $listener = array();

    /**
     * user object
     * @var WBUser_Auth
     */
    protected $user;

    /**
     * Set tree menu object
     *
     * Dependecy injection
     * @param WBDatasource_TreeMenu $treeMenu
     */
    public function setTreeMenu($treeMenu)
    {
        $this->treeMenu =   $treeMenu;
    }

    /**
     * Set id of root menu item
     *
     * Select menu item
     *
     * @param string $id
     */
    public function setRoot($id)
    {
        $this->treeMenu->setRoot($id);
    }

    /**
     * Set list of URLs to ignore
     *
     * In case the URLs match, they will be ignored. Also, all child-URLs will
     * be ignored.
     *
     * E.g: $list = array('http://wombat.exit0.net/foo', 'http://wombat.exit0.net/bar');
     * Ignored URLs
     *    - http://wombat.exit0.net/foo
     *    - http://wombat.exit0.net/bar
     *    - http://wombat.exit0.net/fooblah
     *    - http://wombat.exit0.net/foo/something
     *    - ...
     *
     * @param array $list
     */
    public function ignore($list)
    {
        $this->ignore   =   $list;
    }

    /**
     * Set levels to dig
     *
     * Levels in tree menu to dig down. Set to -1 for unlimited
     *
     * @param int $level
     */
    public function setMaxLevel($level = -1)
    {
        $this->maxLevel =   $level;
    }

    /**
     * Add listener for menu entries
     *
     * @param WBDatasource_MenuDigger_Listener $listener
     */
    public function addListener($listener)
    {
        $this->listener[]   =   $listener;
    }

    /**
     * Start digging
     *
     * Inform listener and load children of root menu
     */
    public function dig()
    {
        $this->init();
        $url    =   $this->treeMenu->getUrlId('');
        $base   =   $this->treeMenu->getMenuCurrent($url);

        foreach ($this->listener as $l) {
            $l->onStart($base);
        }
        $children   =   $this->treeMenu->getMenuChildren($base);

        foreach ($children as $child) {
            $this->digDeeper($child, 1);
        }
        foreach ($this->listener as $l) {
            $l->onEnd($base);
        }
    }

    /**
     * Recursie digging
     *
     * Check level, call listener for item and dig deeper into item's children
     *
     * @param array $item
     * @param int $level
     */
    private function digDeeper($item, $level)
    {
        // reached max level?
        if (0 < $this->maxLevel && $this->maxLevel < $level) {
            return;
        }

        // simply ignore invalid URLs
        if (0 == $item['urlid']) {
            if (0 < $level) {
                return;
            }
        } else {
            $urlid  =   $this->treeMenu->getUrlId($item['url']);
            if (empty($urlid)) {
                return;
            }

            foreach ($this->ignore as $ig) {
                if (strncmp($ig, $item['url'], strlen($ig)) == 0) {
                    return;
                }
            }
        }

        $this->addStatus($item);

        $children   =   $this->treeMenu->getMenuChildren($item);
        foreach ($this->listener as $l) {
            $l->onDigStart($level, $item, $children);
        }

        if (0 == count($children)) {
            foreach ($this->listener as $l) {
                $l->onDigEnd($level, $item, $children);
            }
            return;
        }
        foreach ($children as $child) {
            $this->digDeeper($child, $level + 1);
        }
        foreach ($this->listener as $l) {
            $l->onDigEnd($level, $item, $children);
        }
    }

    /**
     * Add permission status to menu item
     *
     * Check user's grants for this menu item
     *
     * @param array $item
     */
    private function addStatus(&$item)
    {
        $item['satus']  =   '';
        if (!empty($item['requiregroup']) && !$this->user->isInGroup($item['requiregroup'], true)) {
            $item['status']    =   'grouprequired';
            return;
        }

        switch ($item['requireuser']) {
            case 'user':
                if (!$this->user->isAuthenticated()) {
                    $item['status']    =   'userrequired';
                }
                break;

            case 'anonymous':
                if ($this->user->isAuthenticated()) {
                    $item['status']    =   'userdenied';
                }
                break;

            case 'anybody':
            default:
                break;
        }
    }

    /**
     * Make sure tree menu exists
     *
     * Instantiate tree menu and URL dictionary, of not done already
     */
    private function init()
    {
        if (!$this->treeMenu) {
            $this->treeMenu =   WBClass::create('WBDatasource_TreeMenu');
        }
        if (!$this->url) {
            $this->url      =   WBClass::create('WBDictionary_URL');
        }
        if (!$this->user) {
            $this->user =   WBUser::getCurrent();
        }
    }

}