<?
# Lifter002: TODO
# Lifter007: TODO
# Lifter003: TODO
# Lifter010: TODO
/**
* Export xml-functions.
*
* In this file there are several functions to generate xml-tags.
*
* @author       Arne Schroeder <schroeder@data.quest.de>
* @access       public
* @modulegroup      export_modules
* @module       export_xml_functions
* @package      Export
*/
// +---------------------------------------------------------------------------+
// This file is part of Stud.IP
// export_xml_func.inc.php
//
// Copyright (c) 2002 Arne Schroeder <schroeder@data-quest.de>
// Suchi & Berg GmbH <info@data-quest.de>
// +---------------------------------------------------------------------------+
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or any later version.
// +---------------------------------------------------------------------------+
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
// +---------------------------------------------------------------------------+


/**
* create xml_header
*
* This function creates a xml-header for output.
* Its contents are Name of University, Stud.IP-Version, Range of Export (e.g. "root"), and temporal range.
*
* @access   public
* @return       string  xml-header
*/
function xml_header()
{
global $SOFTWARE_VERSION, $ex_type, $ex_sem, $range_name, $range_id;
    $semester = $ex_sem ? Semester::find($ex_sem) : Semester::findCurrent();
    $xml_tag_string = "<" . "?xml version=\"1.0\" encoding=\"utf-8\"?>\n";
    $xml_tag_string .= "<studip version=\"" . xml_escape ($SOFTWARE_VERSION) . "\" logo=\"". xml_escape (Assets::image_path('logos/logo2b.png')) . "\"";
    if ($range_id == "root") $xml_tag_string .= " range=\"" . _("Alle Einrichtungen") . "\"";
    elseif ($range_name != "") $xml_tag_string .= " range=\"" . xml_escape ($range_name) . "\"";
    if (Config::get()->UNI_NAME_CLEAN != "") $xml_tag_string .= " uni=\"" . xml_escape (Config::get()->UNI_NAME_CLEAN) . "\"";
    if ($semester)
        $xml_tag_string .= " zeitraum=\"" . xml_escape ($semester->name) . "\" semester_id=\"" . xml_escape ($semester->getId()) . "\"";
    $xml_tag_string .= ">\n";
    return $xml_tag_string;
}

/**
* create opening xml-tag
*
* This function creates an open xml-tag.
* The tag-name is defined by the given parameter $tag_name.
* An optional parameter allows to set an attribute named "key".
*
* @access   public
* @param        string  tag name
* @param        string  value for optional attribute "key"
* @return       string  xml open tag
*/
function xml_open_tag($tag_name, $tag_key = null)
{
    $xml_tag_string = rtrim(' ' . xml_attributes_to_string(compact('tag_key')));
    $xml_tag_string = "<{$tag_name}{$xml_tag_string}>\n";
    return $xml_tag_string;
}

/**
* create closing xml-tag
*
* This function creates a closed xml-tag.
* The tag-name is defined by the given parameter $tag_name.
*
* @access   public
* @param        string  tag name
* @return       string  xml close tag
*/
function xml_close_tag($tag_name)
{
    $xml_tag_string = "</" . $tag_name .  ">\n";
    return $xml_tag_string;
}

/**
* create xml-tag
*
* This function creates a xml-tag.
* The tag-name is defined by the given parameter $tag_name.
* The given parameter tag_content is put between open tag and close tag.
*
* @access   public
* @param        string  tag name
* @param        string  content for xml-tag
* @param        array   array of tag attributes
* @return       string  xml tag
*/
function xml_tag($tag_name, $tag_content, $tag_attributes = null)
{
    $xml_tag_string = xml_attributes_to_string($tag_attributes ?? []);
    $xml_tag_string = "<{$tag_name}{$xml_tag_string}>"
        . xml_escape ( $tag_content )
        . "</" . $tag_name .  ">\n";
    return $xml_tag_string;
}

/**
* create xml-footer
*
* This function creates the footer for xml output,
* which is a closing "studip"-tag.
*
* @access   public
* @return       string  xml footer
*/
function xml_footer()
{
    $xml_tag_string = "</studip>";
    return $xml_tag_string;
}

/**
 * escapes special characters for xml use
 *
 * @param string $string the string to escape
 * @return string
 */
function xml_escape($string)
{
    $string = preg_replace('/[\x00-\x08\x0b\x0c\x0e-\x1f]/', '', $string);
    return htmlspecialchars($string, ENT_QUOTES, 'UTF-8');
}

function xml_attributes_to_string(array $attributes): string
{
    $attributes = array_filter($attributes, function ($attribute) {
        return $attribute !== null;
    });

    if (count($attributes) === 0) {
        return '';
    }

    $result = ['']; // Empty item for a leading whitespace
    foreach ($attributes as $key => $value) {
        $result[] = sprintf('%s="%s"', $key, xml_escape($value));
    }
    return implode(' ', $result);
}