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

/**
 * Datasource Tree Menu
 *
 * Acces to tree menu itms
 *
 * @version 0.2.0
 * @package WB
 * @subpackage content
 */
class WBDatasource_TreeMenu extends WBStdClass
{
    const SELECT_FIRST  =   'first';
    const SELECT_LAST   =   'last';
    const SELECT_SHORT  =   'short';
    const SELECT_LONG   =   'long';

    /**
     * Tree datasource object
     * @var WBDatasource_Tree
     */
    private $tree;

    /**
     * URL dictionary
     * @var WBDictionary_URL
     */
    protected  $url;

    /**
     * Id of root item
     * @var string
     */
    private $rootId = null;

    /**
     * List of child trees
     * @var array WBDatasource_TreeMenu_Child
     */
    private $childTrees =   array();

    /**
     * Map URLIDs to child trees
     * @var WBDatasource_TreeMenu_Child
     */
    private $childTreeMap   =   array();

    /**
     * constructor
     *
     *
     */
    public function __construct()
    {
        $params =   array(
                        'treetable'     =>  'menu',
                        'alphalength'   =>  4,
                    );
        $this->tree =   WBClass::create('WBDatasource_Tree', $params);
        $this->url  =   WBClass::create('WBDictionary_URL');
    }

    /**
     * Inject cache parameter
     *
     * Cache parameters are used to create a unique cache id.
     * Implement this function to add custom parameters for caching.
     *
     * It is recommended to prefix custom parameter with a namespace plus colon.
     *
     * @param array $params
     */
    public function addCacheIdParams(&$params)
    {
    }

    /**
     * Use list of child-trees
     *
     * @param array $list
     */
    public function useChildTrees($list)
    {
        if (!is_array($list) || empty($list)) {
            return;
        }

        foreach ($list as $l) {
            // normalize config
            if (is_array($l)) {
                if (!is_array($l['params'])) {
                    $l['params']    =   array();
                }

                if (empty($l['name'])) {
                    $ex =   array(
                                    'code'  =>  1,
                                    'class' =>  __CLASS__,
                                    'msg'   =>  'Config of menu tree child is corrupt - the name is missing.'
                                );
                    throw WBClass::create('WBException_Config', $ex);
                }
            }
            else {
                $l  =   array(
                            'name'      =>  $l,
                            'params'    =>  array()
                            );
            }
            $obj    =   WBClass::create('WBDatasource_TreeMenu_Child_' . $l['name'], $l['params']);
            $this->childTrees[] =   $obj;
        }

    }

    /**
     * Set root id
     *
     * Use menu root
     *
     * @param string $id
     */
    public function setRoot($id)
    {
        $this->tree->get($id);
        $this->rootId   =   $id;
    }

    /**
     * Get current root id
     *
     * @return string
     */
    protected function getRootId()
    {
        return $this->rootId;
    }

    /**
     * Get URL id of current page
     *
     * Auxilliary method, can be overwritten
     *
     * @param string $uri
     * @return string $urlid
     */
    public function getUrlId($uri)
    {
        $this->url->addWord($uri);
        return $this->url->getId();
    }

    /**
     * Get selected menu record by URLid
     *
     * @param string $urlid
     * @param string $select
     * @return array curren node
     */
    public function getMenuCurrent($urlid, $select = self::SELECT_FIRST)
    {
        // find current URL in menu
        $clause     =   array();
        $clause[]   =   array(
                            'field' =>  'urlid',
                            'value' =>  $urlid
                        );
        $current        =   $this->tree->getChildren($this->rootId, 0, array(), $clause);
        $childCurrent   =   $this->getMenuCurrentChild($urlid);
        if (empty($current)) {
            $current    =   $childCurrent;
            // if nothing matches load at least the menu
            if (empty($current)) {
                $current    =   $this->tree->get($this->rootId);
            }
        } else {
            $current    =   $this->selectNode($current, $select);
        }


        $this->injectUrl($current);

        return $current;
    }

    /**
     * Select one node
     *
     * @param array $node list of nodes
     * @param string $select
     * @param array selected node
     */
    private function selectNode($node, $select)
    {
        if (1 == count($node)) {
            return $node[0];
        }

        // simply select by position in list
        if (self::SELECT_FIRST == $select) {
            return array_shift($node);
        }
        if (self::SELECT_LAST == $select) {
            return array_pop($node);
        }

        // select by path length - depth in hirachie
        $i = 0;
        $pathLength =   strlen($node[0]['path']);
        for($j = 1; $j < count($node); ++$j) {
            $pl =   strlen($node[$j]['path']);

            switch ($select) {
                case self::SELECT_SHORT:
                    if ($pl < $pathLength) {
                        $pathLength =   $pl;
                        $i  =   $j;
                    }
                    break;

                case self::SELECT_LONG:
                    if ($pl > $pathLength) {
                        $pathLength =   $pl;
                        $i  =   $j;
                    }
                    break;
            }
        }

        return $node[$i];
    }

    private function getMenuCurrentChild($urlid)
    {
        $url    =   clone $this->url;
        $url->load($urlid);
        if (empty($this->childTrees)) {
            return array();
        }

        foreach ($this->childTrees as $ct) {
            if ($ct->checkUrl($url->getWord())) {
                return $ct->getNode($url->getId(), $url->getWord());
            }
        }

        return array();
    }

    /**
     * Get ancestors
     *
     * Receive list of parents from menu tree. Auxilliary method can be overwritten
     *
     * @param array $current node
     * @return array
     */
    public function getMenuParents($current)
    {
        $childish   =   array();
        foreach ($this->childTrees as $ct) {
            if ($ct->checkUrl($current['url'])) {
                $childish   =   $ct->getParents($current);
                break;
            }
        }

        // load ascending parents
        if (empty($childish)) {
            $parents    =   $this->tree->getParent($current['id'], 0);
        }
        else {
            $clause     =   array();
            $clause[]   =   array(
                                'field' =>  'urlid',
                                'value' =>  $childish[0]['urlid']
                            );

            array_pop($childish);

            $tmp            =   $this->tree->getChildren($this->rootId, 0, array(), $clause);
            $childish[0]    =   $tmp[0];
            $parents        =   $this->tree->getParent($tmp[0]['id'], 0);
            $parents        =   array_merge($parents, $childish);
        }
        $parents[]  =   $current;
        foreach ($parents as &$node) {
            $this->injectUrl($node);
        }
        return $parents;
    }

    /**
     * Get direct offspring of parent node
     *
     * Receive children from menu tree
     *
     * @param array $parent node
     * @return array
     */
    public function getMenuChildren($parent)
    {
        foreach ($this->childTrees as $ct) {
            if ($ct->checkUrl($parent['url'])) {
                return $ct->getChildren($parent['url']);
            }
        }

        $children   =   $this->tree->getChildren($parent['id']);
        foreach ($children as &$node) {
            $this->injectUrl($node);
        }
        return $children;
    }

    /**
     * Select menu node by id
     *
     * @param string $id
     * @return array
     */
    public function getMenuNode($id)
    {
        $node   =   $this->tree->get($id);
        $this->injectUrl($node);
        return $node;
    }

    /**
     * Inject URL into node
     *
     * Locate URL-id and set "url" either to [[SERVICE_HTML]]
     * or the actual URL of the Dictionary_URL item
     *
     * @param array $node
     */
    private function injectUrl(&$node)
    {
        if (isset($node['url']) && !empty($node['url'])) {
            return;
        }
        if (0 == $node['urlid']) {
            $node['url']    =   '[[SERVICE_HTML]]';
            return;
        }

        $this->url->load($node['urlid']);
        $node['url']    =   $this->url->getWord();
    }
}