class.ilExplorer.php

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<?php
/* Copyright (c) 1998-2009 ILIAS open source, Extended GPL, see docs/LICENSE */

define("IL_FM_POSITIVE", 1);
define("IL_FM_NEGATIVE", 2);

class ilExplorer
{
        var $id;
        
        var $ilias;

        var $output;

        var $format_options;

        var $tree;

        var $target;

        var $target_get;

        var $params_get;

        var $expanded;

        var $order_column;

        var $order_direction = "asc";

        var $expand_target;

        var $rbac_check;


        var $output_icons;

        var $expand_variable;

        var $is_clickable;

        var $post_sort;

        var $filtered = false;

        var $filter_mode;

        var $expand_all = false;
        
        var $root_id = null;
        
        var $use_standard_frame = false;

        function __construct($a_target)
        {
                global $ilias, $objDefinition;

                if (!isset($a_target) or !is_string($a_target))
                {
                        $this->ilias->raiseError(get_class($this)."::Constructor(): No target given!",$this->ilias->error_obj->WARNING);
                }

                // autofilter object types in devmode
                $devtypes = $objDefinition->getDevModeAll();

                if (count($devtypes > 0))
                {
                        // activate filter if objects found in devmode
                        $this->setFiltered(true);

                        foreach ($devtypes as $type)
                        {
                                $this->addFilter($type);
                        }
                }

                $this->ilias = $ilias;
                $this->output = array();
                $this->expanded = array();
                $this->target = $a_target;
                $this->target_get = 'ref_id';
                $this->frame_target = "content";
                $this->order_column = "title";
                $this->tree = new ilTree(ROOT_FOLDER_ID);
                $this->tree->initLangCode();
                $this->expand_target = $_SERVER["PATH_INFO"];
                $this->rbac_check = true;
                $this->output_icons = true;
                $this->expand_variable = "expand";
                $this->setTitleLength(50);
                $this->post_sort=true;
                $this->setFilterMode(IL_FM_NEGATIVE);
                $this->highlighted = "";
                $this->show_minus = true;
                $this->counter = 0;
                $this->asnch_expanding = false;
        }

        function setId($a_val)
        {
                $this->id = $a_val;
        }
        
        function getId()
        {
                return $this->id;
        }
        
        function setAsynchExpanding($a_val)
        {
                $this->asnch_expanding = $a_val;
        }

        function getAsynchExpanding()
        {
                return $this->asnch_expanding;
        }

        public function initItemCounter($a_number)
        {
                $this->counter = $a_number;
        }
        
        function setTitle($a_val)
        {
                $this->title = $a_val;
        }
        
        public function setTitleLength($a_length)
        {
                $this->textwidth = $a_length;
        }
        
        public function getTitleLength()
        {
                return $this->textwidth;
        }
        
        function getTitle()
        {
                return $this->title;
        }
        
        public function setRoot($a_root_id)
        {
                #$this->tree = new ilTree(ROOT_FOLDER_ID,$a_root_id);
                $this->root_id = $a_root_id;
        }
        
        public function getRoot()
        {
                return $this->root_id == null ?
                        $this->tree->getRootId() :
                        $this->root_id;
        }

        function setOrderColumn($a_column)
        {
                $this->order_column = $a_column;
        }

        function setOrderDirection($a_direction)
        {
                if ($a_direction == "desc")
                {
                        $this->order_direction = $a_direction;
                }
                else
                {
                        $this->order_direction = "asc";
                }
        }

        function setTargetGet($a_target_get)
        {
                if (!isset($a_target_get) or !is_string($a_target_get))
                {
                        $this->ilias->raiseError(get_class($this)."::setTargetGet(): No target given!",$this->ilias->error_obj->WARNING);
                }

                $this->target_get = $a_target_get;
        }

        function setParamsGet($a_params_get)
        {
                if (!isset($a_params_get) or !is_array($a_params_get))
                {
                        $this->ilias->raiseError(get_class($this)."::setTargetGet(): No target given!",$this->ilias->error_obj->WARNING);
                }

                foreach ($a_params_get as $key => $val)
                {
                        $str .= "&".$key."=".$val;
                }

                $this->params_get = $str;
        }


        function setExpandTarget($a_exp_target)
        {
                $this->expand_target = $a_exp_target;
        }
        
        function setFrameUpdater($a_up_frame, $a_up_script, $a_params = "")
        {
                $this->up_frame = $a_up_frame;
                $this->up_script = $a_up_script;
                $this->up_params = $a_params;
        }

        
        function highlightNode($a_id)
        {
                $this->highlighted = $a_id;
        }

        function checkPermissions($a_check)
        {
                $this->rbac_check = $a_check;
        }

        function setSessionExpandVariable($a_var_name = "expand")
        {
                $this->expand_variable = $a_var_name;
        }

        function outputIcons($a_icons)
        {
                $this->output_icons = $a_icons;
        }


        function setClickable($a_type, $a_clickable)
        {
                if($a_clickable)
                {
                        $this->is_clickable[$a_type] = "";
                }
                else
                {
                        $this->is_clickable[$a_type] = "n";
                }
        }

        function isVisible($a_ref_id,$a_type)
        {
                global $rbacsystem, $ilBench;
                
                if (!$this->rbac_check)
                {
                        return true;
                }
                
                $ilBench->start("Explorer", "setOutput_isVisible");
                $visible = $rbacsystem->checkAccess('visible',$a_ref_id);
                $ilBench->stop("Explorer", "setOutput_isVisible");

                return $visible;
        }

        public function setTreeLead($a_val)
        {
                $this->tree_lead = $a_val;
        }

        public function getTreeLead()
        {
                return $this->tree_lead;
        }

        function isClickable($a_type, $a_ref_id = 0)
        {
                // in this standard implementation
                // only the type determines, wether an object should be clickable or not
                // but this method can be overwritten and make $exp->setFilterMode(IL_FM_NEGATIVE);use of the ref id
                // (this happens e.g. in class ilRepositoryExplorerGUI)
                if ($this->is_clickable[$a_type] == "n")
                {
                        return false;
                }
                else
                {
                        return true;
                }
        }

        function setPostSort($a_sort)
        {
                $this->post_sort = $a_sort;
        }

        function setFilterMode($a_mode = IL_FM_NEGATIVE)
        {
                $this->filter_mode = $a_mode;
        }

        function getFilterMode()
        {
                return $this->filter_mode;
        }

        function setUseStandardFrame($a_val)
        {
                $this->use_standard_frame = $a_val;
        }
        
        function getUseStandardFrame()
        {
                return $this->use_standard_frame;
        }
        
        function getChildsOfNode($a_parent_id)
        {
                return $this->tree->getChilds($a_parent_id, $this->order_column);
        }
        
        
        function setOutput($a_parent_id, $a_depth = 1,$a_obj_id = 0, $a_highlighted_subtree = false)
        {
                global $rbacadmin, $rbacsystem, $ilBench;

#echo 'ParentId: '.$a_parent_id.' depth: '.$a_depth.' obj_id: '.$a_obj_id;

                if (!isset($a_parent_id))
                {
                        $this->ilias->raiseError(get_class($this)."::setOutput(): No node_id given!",$this->ilias->error_obj->WARNING);
                }

                if ($this->showChilds($a_parent_id,$a_obj_id))
                {
                        $objects = $this->getChildsOfNode($a_parent_id);
                }
                else
                {
                        $objects = array();
                }

                $objects = $this->modifyChilds($a_parent_id, $objects);

                // force expansion (of single nodes)
                if ($this->forceExpanded($a_parent_id) && !in_array($a_parent_id, $this->expanded))
                {
                        $this->expanded[] = $a_parent_id;
                }

                if (count($objects) > 0)
                {
                        // Maybe call a lexical sort function for the child objects
                        $tab = ++$a_depth - 2;
                        if ($this->post_sort)
                        {
                                $objects = $this->sortNodes($objects,$a_obj_id);
                        }
                        $skip_rest = false;
                        foreach ($objects as $key => $object)
                        {
                                // skip childs, if parent is not expanded
                                if (!$this->forceExpanded($object["child"]) && $skip_rest)
                                {
                                        continue;
                                }
//echo "<br>-".$object["child"]."-".$this->forceExpanded($object["child"])."-";
                                //ask for FILTER
                                if ($this->filtered == false or $this->checkFilter($object["type"]) == false)
                                {
                                        if ($this->isVisible($object['child'],$object['type']))
                                        {
                                                $ilBench->start("Explorer", "setOutput_setFormatOptions");
                                                #echo 'CHILD getIndex() '.$object['child'].' parent: '.$this->getRoot();
                                                if ($object["child"] != $this->getRoot())
                                                {
                                                        $parent_index = $this->getIndex($object);
                                                }
                                                $this->format_options["$this->counter"]["parent"]               = $object["parent"];
                                                $this->format_options["$this->counter"]["child"]                = $object["child"];
                                                $this->format_options["$this->counter"]["title"]                = $object["title"];
                                                $this->format_options["$this->counter"]["type"]         = $object["type"];
                                                $this->format_options["$this->counter"]["obj_id"]               = $object["obj_id"];
                                                $this->format_options["$this->counter"]["desc"]                 = "obj_".$object["type"];
                                                $this->format_options["$this->counter"]["depth"]                = $tab;
                                                $this->format_options["$this->counter"]["container"]    = false;
                                                $this->format_options["$this->counter"]["visible"]      = true;
                                                $this->format_options["$this->counter"]["highlighted_subtree"] = $a_highlighted_subtree;

                                                // Create prefix array
                                                for ($i = 0; $i < $tab; ++$i)
                                                {
                                                         $this->format_options["$this->counter"]["tab"][] = 'blank';
                                                }

                                                // fix explorer (sometimes explorer disappears)
                                                if ($parent_index == 0)
                                                {
                                                        if (!$this->expand_all and !in_array($object["parent"], $this->expanded))
                                                        {
                                                                $this->expanded[] = $object["parent"];
                                                        }
                                                }

                                                // only if parent is expanded and visible, object is visible
                                                if ($object["child"] != $this->getRoot() and ((!$this->expand_all and !in_array($object["parent"],$this->expanded))
                                                   or !$this->format_options["$parent_index"]["visible"]))
                                                {
                                                        if (!$this->forceExpanded($object["child"]))
                                                        {
                                                                // if parent is not expanded, and one child is
                                                                // visible we don't need more information and
                                                                // can skip the rest of the childs
                                                                if ($this->format_options["$this->counter"]["visible"])
                                                                {
//echo "-setSkipping";
                                                                        $skip_rest = true;
                                                                }
                                                                $this->format_options["$this->counter"]["visible"] = false;
                                                        }
                                                }

                                                // if object exists parent is container
                                                if ($object["child"] != $this->getRoot())
                                                {
                                                        $this->format_options["$parent_index"]["container"] = true;

                                                        if ($this->expand_all or in_array($object["parent"],$this->expanded))
                                                        {
        //echo "<br>-".$object["child"]."-".$this->forceExpanded($object["child"])."-";
                                                                if ($this->forceExpanded($object["parent"]))
                                                                {
                                                                        $this->format_options["$parent_index"]["tab"][($tab-2)] = 'forceexp';
                                                                }
                                                                else
                                                                {
                                                                        $this->format_options["$parent_index"]["tab"][($tab-2)] = 'minus';
                                                                }
                                                        }
                                                        else
                                                        {
                                                                $this->format_options["$parent_index"]["tab"][($tab-2)] = 'plus';
                                                        }
                                                }
        //echo "-"."$parent_index"."-";
        //var_dump($this->format_options["$parent_index"]);
                                                ++$this->counter;
                                                $ilBench->stop("Explorer", "setOutput_setFormatOptions");
                                                
                                                // stop recursion if 2. level beyond expanded nodes is reached
                                                if ($this->expand_all or in_array($object["parent"],$this->expanded) or ($object["parent"] == 0)
                                                        or $this->forceExpanded($object["child"]))
                                                {
                                                        $highlighted_subtree = ($a_highlighted_subtree ||
                                                                ($object["child"] == $this->highlighted))
                                                                ? true
                                                                : false;
                                                        
                                                        // recursive
                                                        $this->setOutput($object["child"],$a_depth,$object['obj_id'], $highlighted_subtree);
                                                }
                                        } //if
                                } //if FILTER
                        } //foreach
                } //if
        } //function

        function modifyChilds($a_parent_id, $a_objects)
        {
                return $a_objects;
        }

        function showChilds($a_parent_id)
        {
                return true;
        }

        function forceExpanded($a_obj_id)
        {
                return false;
        }

        function getMaximumTreeDepth()
        {
                $this->tree->getMaximumDepth();
        }
        
        
        function getOutput()
        {
                global $ilBench, $tpl, $lng;

                $ilBench->start("Explorer", "getOutput");

                $this->format_options[0]["tab"] = array();

                $depth = $this->getMaximumTreeDepth();

                for ($i=0;$i<$depth;++$i)
                {
                        $this->createLines($i);
                }

                include_once("./Services/YUI/classes/class.ilYuiUtil.php");
                ilYuiUtil::initConnection();
                $tpl->addJavaScript("./Services/UIComponent/Explorer/js/ilExplorer.js");

//echo "hh";
                // set global body class
//              $tpl->setBodyClass("il_Explorer");
                
                $tpl_tree = new ilTemplate("tpl.tree.html", true, true, "Services/UIComponent/Explorer");
                
                // updater
                if (($_GET["ict"] || $_POST["collapseAll"] != "" || $_POST["expandAll"] != "") && $this->up_frame != "")
                {
                        $tpl_tree->setCurrentBlock("updater");
                        $tpl_tree->setVariable("UPDATE_FRAME", $this->up_frame);
                        $tpl_tree->setVariable("UPDATE_SCRIPT", $this->up_script);
                        if (is_array($this->up_params))
                        {
                                $up_str = $lim = "";
                                foreach ($this->up_params as $p)
                                {
                                        $up_str.=  $lim."'".$p."'";
                                        $lim = ",";
                                }
                                $tpl_tree->setVariable("UPDATE_PARAMS", $up_str);
                        }
                        $tpl_tree->parseCurrentBlock();
                }
                
                $cur_depth = -1;
                foreach ($this->format_options as $key => $options)
                {
//echo "-".$options["depth"]."-";
                        if (!$options["visible"])
                        {
                                continue;
                        }
                        
                        // end tags
                        $this->handleListEndTags($tpl_tree, $cur_depth, $options["depth"]);
                        
                        // start tags
                        $this->handleListStartTags($tpl_tree, $cur_depth, $options["depth"]);
                        
                        $cur_depth = $options["depth"];
                        
                        if ($options["visible"] and $key != 0)
                        {
                                $this->formatObject($tpl_tree, $options["child"],$options,$options['obj_id']);
                        }
                        if ($key == 0)
                        {
                                $this->formatHeader($tpl_tree, $options["child"],$options);
                        }
                                                
                }
//if ($GLOBALS["ilUser"]->getLogin() == "alex") var_dump($this->format_options);
                $this->handleListEndTags($tpl_tree, $cur_depth, -1);
                
                $ilBench->stop("Explorer", "getOutput");

                $tpl_tree->setVariable("TREE_LEAD", "");
                if ($this->tree_lead != "")
                {
                        $tpl_tree->setCurrentBlock("tree_lead");
                        $tpl_tree->setVariable("TREE_LEAD", $this->tree_lead);
                        $tpl_tree->parseCurrentBlock();
                }
                if ($this->getId() != "")
                {
                        $tpl_tree->setVariable("TREE_ID", 'id="'.$this->getId().'_tree"');
                }

                $html = $tpl_tree->get();
                
                if ($this->getUseStandardFrame())
                {
                        $mtpl = new ilTemplate("tpl.main.html", true, true);
                        $mtpl->setVariable("LOCATION_STYLESHEET", ilUtil::getStyleSheetLocation());
                        $mtpl->setVariable("BODY_CLASS", "il_Explorer");
                        $mtpl->addBlockFile("CONTENT", "content", "tpl.explorer.html");
                        if ($this->getTitle() != "")
                        {
                                $mtpl->setVariable("TXT_EXPLORER_HEADER", $this->getTitle());
                        }
                        if ($this->getId() != "")
                        {
                                $mtpl->setVariable("ID", 'id="'.$this->getId().'"');
                        }
                        $mtpl->setVariable("IMG_SPACE", ilUtil::getImagePath("spacer.png", false));
                        $mtpl->setCurrentBlock("content");
                        $mtpl->setVariable("EXPLORER", $html);
                        $mtpl->setVariable("EXP_REFRESH", $lng->txt("refresh"));
                        $mtpl->parseCurrentBlock();
                        $html = $mtpl->get();
                }
                
                return $html;
        }
        
        
        
        function handleListEndTags(&$a_tpl_tree, $a_cur_depth, $a_item_depth)
        {
                if ($a_item_depth < $a_cur_depth)
                {
                        // </li></ul> for ending lists
                        for ($i = 0; $i < ($a_cur_depth - $a_item_depth); $i++)
                        {
                                $a_tpl_tree->touchBlock("end_list_item");
                                $a_tpl_tree->touchBlock("element");

                                $a_tpl_tree->touchBlock("end_list");
                                $a_tpl_tree->touchBlock("element");
                        }
                }
                else if ($a_item_depth == $a_cur_depth)
                {
                        // </li> for ending list items
                        $a_tpl_tree->touchBlock("end_list_item");
                        $a_tpl_tree->touchBlock("element");
                }
        }
        
        function handleListStartTags(&$a_tpl_tree, $a_cur_depth, $a_item_depth)
        {
                // start tags
                if ($a_item_depth > $a_cur_depth)
                {
                        // <ul><li> for new lists
                        if ($a_item_depth > 1)
                        {
                                $a_tpl_tree->touchBlock("start_list");
                        }
                        else
                        {
                                $a_tpl_tree->touchBlock("start_list_no_indent");
                        }
                        $a_tpl_tree->touchBlock("element");
                        
                        $a_tpl_tree->touchBlock("start_list_item");
                        $a_tpl_tree->touchBlock("element");
                }
                else
                {
                        // <li> items
                        $a_tpl_tree->touchBlock("start_list_item");
                        $a_tpl_tree->touchBlock("element");
                }
        }

        function formatHeader($tpl,$a_obj_id,$a_option)
        {
        }

        function formatObject($tpl, $a_node_id,$a_option,$a_obj_id = 0)
        {
                global $lng;
                if (!isset($a_node_id) or !is_array($a_option))
                {
                        $this->ilias->raiseError(get_class($this)."::formatObject(): Missing parameter or wrong datatype! ".
                                                                        "node_id: ".$a_node_id." options:".var_dump($a_option),$this->ilias->error_obj->WARNING);
                }

                $pic = false;
                foreach ((array) $a_option["tab"] as $picture)
                {
                        if ($picture == 'plus')
                        {
                                $tpl->setCurrentBlock("expander");
                                $tpl->setVariable("EXP_DESC", $lng->txt("collapsed"));
                                $tpl->setVariable("LINK_NAME", $a_node_id);
                                if (!$this->getAsynchExpanding())
                                {
                                        $target = $this->createTarget('+',$a_node_id, $a_option["highlighted_subtree"]);
                                        $tpl->setVariable("LINK_TARGET_EXPANDER", $target);
                                }
                                else
                                {
                                        $target = $this->createTarget('+',$a_node_id, $a_option["highlighted_subtree"], false);
                                        $tpl->setVariable("ONCLICK_TARGET_EXPANDER", " onclick=\"return il.Explorer.refresh('tree_div', '".$target."');\"");
                                        $tpl->setVariable("LINK_TARGET_EXPANDER", "#");
                                }
                                $tpl->setVariable("IMGPATH", $this->getImage("browser/plus.png"));
                                $tpl->parseCurrentBlock();
                                $pic = true;
                        }

                        if ($picture == 'forceexp')
                        {
                                $tpl->setCurrentBlock("expander");
                                $tpl->setVariable("EXP_DESC", $lng->txt("expanded"));
                                $target = $this->createTarget('+',$a_node_id);
                                $tpl->setVariable("LINK_NAME", $a_node_id);
                                $tpl->setVariable("LINK_TARGET_EXPANDER", $target);
                                $tpl->setVariable("IMGPATH", $this->getImage("browser/forceexp.png"));
                                $tpl->parseCurrentBlock();
                                $pic = true;
                        }

                        if ($picture == 'minus' && $this->show_minus)
                        {
                                $tpl->setCurrentBlock("expander");
                                $tpl->setVariable("EXP_DESC", $lng->txt("expanded"));
                                $tpl->setVariable("LINK_NAME", $a_node_id);
                                if (!$this->getAsynchExpanding())
                                {
                                        $target = $this->createTarget('-',$a_node_id, $a_option["highlighted_subtree"]);
                                        $tpl->setVariable("LINK_TARGET_EXPANDER", $target);
                                }
                                else
                                {
                                        $target = $this->createTarget('-',$a_node_id, $a_option["highlighted_subtree"], false);
                                        $tpl->setVariable("ONCLICK_TARGET_EXPANDER", " onclick=\"return il.Explorer.refresh('tree_div', '".$target."');\"");
                                        $tpl->setVariable("LINK_TARGET_EXPANDER", "#");
                                }
                                $tpl->setVariable("IMGPATH", $this->getImage("browser/minus.png"));
                                $tpl->parseCurrentBlock();
                                $pic = true;
                        }

                }
                
                if (!$pic)
                {
                        $tpl->setCurrentBlock("blank");
                        $tpl->setVariable("BLANK_PATH", $this->getImage("browser/blank.png"));
                        $tpl->parseCurrentBlock();
                }

                if ($this->output_icons)
                {
                        $tpl->setCurrentBlock("icon");
                        $tpl->setVariable("ICON_IMAGE" , $this->getImage("icon_".$a_option["type"].".svg", $a_option["type"], $a_obj_id));
                        
                        $tpl->setVariable("TARGET_ID" , "iconid_".$a_node_id);
                        $this->iconList[] = "iconid_".$a_node_id;
                        $tpl->setVariable("TXT_ALT_IMG",
                                $this->getImageAlt($lng->txt("icon")." ".$lng->txt($a_option["desc"]), $a_option["type"], $a_obj_id));
                        $tpl->parseCurrentBlock();
                }
                
                if(strlen($sel = $this->buildSelect($a_node_id,$a_option['type'])))
                {
                        $tpl->setCurrentBlock('select');
                        $tpl->setVariable('OBJ_SEL',$sel);
                        $tpl->parseCurrentBlock();
                }

                if ($this->isClickable($a_option["type"], $a_node_id,$a_obj_id))        // output link
                {
                        $tpl->setCurrentBlock("link");
                        //$target = (strpos($this->target, "?") === false) ?
                        //      $this->target."?" : $this->target."&";
                        //$tpl->setVariable("LINK_TARGET", $target.$this->target_get."=".$a_node_id.$this->params_get);
                        $tpl->setVariable("LINK_TARGET", $this->buildLinkTarget($a_node_id, $a_option["type"]));
                                
                        $style_class = $this->getNodeStyleClass($a_node_id, $a_option["type"]);
                        
                        if ($style_class != "")
                        {
                                $tpl->setVariable("A_CLASS", ' class="'.$style_class.'" ' );
                        }

                        if (($onclick = $this->buildOnClick($a_node_id, $a_option["type"], $a_option["title"])) != "")
                        {
                                $tpl->setVariable("ONCLICK", "onClick=\"$onclick\"");
                        }

                        //$tpl->setVariable("LINK_NAME", $a_node_id);
                        $tpl->setVariable("TITLE", ilUtil::shortenText(
                                $this->buildTitle($a_option["title"], $a_node_id, $a_option["type"]),
                                $this->textwidth, true));
                        $tpl->setVariable("DESC", ilUtil::shortenText(
                                $this->buildDescription($a_option["description"], $a_node_id, $a_option["type"]), $this->textwidth, true));
                        $frame_target = $this->buildFrameTarget($a_option["type"], $a_node_id, $a_option["obj_id"]);
                        if ($frame_target != "")
                        {
                                $tpl->setVariable("TARGET", " target=\"".$frame_target."\"");
                        }
                        $tpl->parseCurrentBlock();
                }
                else                    // output text only
                {
                        $tpl->setCurrentBlock("text");
                        $tpl->setVariable("OBJ_TITLE", ilUtil::shortenText(
                                $this->buildTitle($a_option["title"], $a_node_id, $a_option["type"]), $this->textwidth, true));
                        $tpl->setVariable("OBJ_DESC", ilUtil::shortenText(
                                $this->buildDescription($a_option["desc"], $a_node_id, $a_option["type"]), $this->textwidth, true));                    
                        $tpl->parseCurrentBlock();
                }

                $tpl->setCurrentBlock("list_item");
                $tpl->parseCurrentBlock();
                $tpl->touchBlock("element");
        }

        function getImage($a_name, $a_type = "", $a_obj_id = "")
        {
                return ilUtil::getImagePath($a_name);
        }
        
        function getImageAlt($a_default_text, $a_type = "", $a_obj_id = "")
        {
                return $a_default_text;
        }
        
        function getNodeStyleClass($a_id, $a_type)
        {
                if ($a_id == $this->highlighted)
                {
                        return "il_HighlightedNode";
                }
                return "";
        }

        function buildLinkTarget($a_node_id, $a_type)
        {
                $target = (strpos($this->target, "?") === false)
                        ? $this->target."?"
                        : $this->target."&";
                return $target.$this->target_get."=".$a_node_id.$this->params_get;
        }

        function buildOnClick($a_node_id, $a_type, $a_title)
        {
                return "";
        }

        function buildTitle($a_title, $a_id, $a_type)
        {
                return $a_title;
        }

        function buildDescription($a_desc, $a_id, $a_type)
        {
                return "";
        }
        
        function buildSelect($a_node_id,$a_type)
        {
                return "";
        }
        

        function buildFrameTarget($a_type, $a_child = 0, $a_obj_id = 0)
        {
                return $this->frame_target;
        }


        function createTarget($a_type,$a_node_id,$a_highlighted_subtree = false, $a_append_anch = true)
        {
                if (!isset($a_type) or !is_string($a_type) or !isset($a_node_id))
                {
                        $this->ilias->raiseError(get_class($this)."::createTarget(): Missing parameter or wrong datatype! ".
                                                                        "type: ".$a_type." node_id:".$a_node_id,$this->ilias->error_obj->WARNING);
                }

                // SET expand parameter:
                //     positive if object is expanded
                //     negative if object is compressed
                $a_node_id = $a_type == '+' ? $a_node_id : -(int) $a_node_id;

                $sep = (is_int(strpos($this->expand_target, "?")))
                        ? "&"
                        : "?";
                
                // in current tree flag
                $ict_str = ($a_highlighted_subtree || $this->highlighted == "")
                        ? "&ict=1"
                        : "";
                if ($this->getAsynchExpanding())
                {
                        $ict_str.= "&cmdMode=asynch";
                }
                if ($a_append_anch)
                {
                        return $this->expand_target.$sep.$this->expand_variable."=".$a_node_id.$this->params_get.$ict_str."#".abs($a_node_id);
                }
                else
                {
                        return $this->expand_target.$sep.$this->expand_variable."=".$a_node_id.$this->params_get.$ict_str;
                }
        }

        function setFrameTarget($a_target)
        {
                $this->frame_target = $a_target;
        }

        function createLines($a_depth)
        {
                for ($i = 0; $i < count($this->format_options); ++$i)
                {
                        if ($this->format_options[$i]["depth"] == $a_depth+1
                           and !$this->format_options[$i]["container"]
                                and $this->format_options[$i]["depth"] != 1)
                        {
                                $this->format_options[$i]["tab"]["$a_depth"] = "quer";
                        }

                        if ($this->format_options[$i]["depth"] == $a_depth+2)
                        {
                                if ($this->is_in_array($i+1,$this->format_options[$i]["depth"]))
                                {
                                        $this->format_options[$i]["tab"]["$a_depth"] = "winkel";
                                }
                                else
                                {
                                        $this->format_options[$i]["tab"]["$a_depth"] = "ecke";
                                }
                        }

                        if ($this->format_options[$i]["depth"] > $a_depth+2)
                        {
                                if ($this->is_in_array($i+1,$a_depth+2))
                                {
                                        $this->format_options[$i]["tab"]["$a_depth"] = "hoch";
                                }
                        }
                }
        }

        function is_in_array($a_start,$a_depth)
        {
                for ($i=$a_start;$i<count($this->format_options);++$i)
                {
                        if ($this->format_options[$i]["depth"] < $a_depth)
                        {
                                break;
                        }

                        if ($this->format_options[$i]["depth"] == $a_depth)
                        {
                                return true;
                        }
                }
                return false;
        }

        function getIndex($a_data)
        {
                if(!is_array($this->format_options))
                {
                        return -1;
                }
                
                foreach ($this->format_options as $key => $value)
                {
                        if (($value["child"] == $a_data["parent"]))
                        {
                                return $key;
                        }
                }
                
                return -1;
                // exit on error
                #$this->ilias->raiseError(get_class($this)."::getIndex(): Error in tree. No index found!",$this->ilias->error_obj->FATAL);
        }

        function addFilter($a_item)
        {
                $ispresent = 0;

                if (is_array($this->filter))
                {
                        //run through filter
                    foreach ($this->filter as $item)
                        {
                                if ($item == $a_item)
                                {
                                    $is_present = 1;

                                        return false;
                                }
                        }
                }
                else
                {
                        $this->filter = array();
                }
                if ($is_present == 0)
                {
                        $this->filter[] = $a_item;
                }

                return true;
        }

        function delFilter($a_item)
        {
                //check if a filter exists
                if (is_array($this->filter))
                {
                        //build copy of the existing filter without the given item
                        $tmp = array();

                        foreach ($this->filter as $item)
                    {
                                if ($item != $a_item)
                                {
                                    $tmp[] = $item;
                                }
                                else
                                {
                                        $deleted = 1;
                                }
                        }

                        $this->filter = $tmp;
                }
                else
                {
                        return false;
                }

                if ($deleted == 1)
                {
                        return true;
                }
                else
                {
                        return false;
                }
        }

        function setExpand($a_node_id)
        {
                // IF ISN'T SET CREATE SESSION VARIABLE
                if(!is_array($_SESSION[$this->expand_variable]))
                {
                        $_SESSION[$this->expand_variable] = array($this->getRoot());
                }
                // IF $_GET["expand"] is positive => expand this node
                if ($a_node_id > 0 && !in_array($a_node_id,$_SESSION[$this->expand_variable]))
                {
                        array_push($_SESSION[$this->expand_variable],$a_node_id);
                }
                // IF $_GET["expand"] is negative => compress this node
                if ($a_node_id < 0)
                {
                        $key = array_keys($_SESSION[$this->expand_variable],-(int) $a_node_id);
                        unset($_SESSION[$this->expand_variable][$key[0]]);
                }
                $this->expanded = $_SESSION[$this->expand_variable];
        }

        function forceExpandAll($a_mode, $a_show_minus = true)
        {
                $this->expand_all = (bool) $a_mode;
                $this->show_minus = $a_show_minus;
        }

        function setFiltered($a_bool)
        {
                $this->filtered = $a_bool;
                return true;
        }

        function checkFilter($a_item)
        {
                if (is_array($this->filter))
                {
                        if (in_array($a_item, $this->filter))
                        {
                                $ret = true;
                        }
                        else
                        {
                                $ret = false;
                        }
                }
                else
                {
                        $ret = false;
                }

                if ($this->getFilterMode() == IL_FM_NEGATIVE )
                {
                        return $ret;
                }
                else
                {
                        return !$ret;
                }
        }

        function sortNodes($a_nodes,$a_parent_obj_id)
        {
                foreach ($a_nodes as $key => $node)
                {
                        if ($node["type"] == "adm")
                        {
                                $match = $key;
                                $adm_node = $node;
                                break;
                        }
                }

                // cut off adm node
                isset($match) ? array_splice($a_nodes,$match,1) : "";

                $a_nodes = ilUtil::sortArray($a_nodes,$this->order_column,$this->order_direction);

                // append adm node to end of list
                isset ($match) ? array_push($a_nodes,$adm_node) : "";

                return $a_nodes;
        }
} // END class.ilExplorer
?>