path: root/xml.class

<?php
/*
**	$Id$
**
**	it_xml.class - XML parser / object factory
**
**      ITools - the Internet Tools Library
**
**      Copyright (C) 1995-2005 by the ITools Authors.
**      This program is free software; you can redistribute it and/or
**      modify it under the terms of either the GNU General Public License
**      or the GNU Lesser General Public License, as published by the Free
**      Software Foundation. See http://www.gnu.org/licenses/ for details.
*/

class it_xml
{
/* 
 * Add xml snippet as attribute tree to $this
 * @param $xmldata XML string or filehandle (result from fopen) to parse
 * @param $p associative array
 *	forcearray xml tags to ALWAYS return as array
 *	safety value 2 causes program abort with invalid xml, 1 causes error report
 *	encoding Output character encoding (e.g. UTF-8, default: ISO-8859-1)
 *	prefix Optional prefix for class names
 *	lowercase Lowercase all tag and attribute names
 * @return XML object tree or null on failure
 */

function it_xml($xmldata = "", $p = array())
{
	if ($xmldata)
		$this->from_xml($xmldata, $p);
}

/**
 * Factory method to return XML object tree from XML string. Params like constructor
 * Example: $root = it_xml::create("<a><b id='2'/></a>", array("b"));
 */

function create($xmldata, $p = array())
{
	$xml = new it_xml;

	return $xml->from_xml($xmldata, array('factory' => true) + $p) ? $xml->_root : null;
}

function from_xml($xmldata, $p)
{
	$this->_p = $p + array('encoding' => "ISO-8859-1");
	$this->_arrayforce = array_flip((array)$this->_p['forcearray']);
	$this->_stack = array();
	unset($this->error);
	$parser = xml_parser_create($this->_p['encoding']);
	xml_set_object($parser, $this);
	xml_set_element_handler($parser, "start_element", "end_element");
	xml_set_character_data_handler($parser, "character_data");
	xml_parser_set_option($parser, XML_OPTION_CASE_FOLDING, 0);
	
	$result = true;

	if (is_resource($xmldata))
	{
		if (!preg_match('/^<\?xml/', ($head = fread($xmldata, 1024 * 1024))))	# Prepend XML header for charset detection in PHP5
			$head = '<?xml version="1.0" encoding="' . $this->_p['encoding'] . '"?>' . $head;

		$result = xml_parse($parser, $head, false);

		while ($result && !feof($xmldata))
			$result = xml_parse($parser, fread($xmldata, 1024 * 1024), false);

		if ($result)
			$result = xml_parse($parser, "", true);
	}
	else
	{
		if (!preg_match('/^<\?xml/', $xmldata))	# Prepend XML header for charset detection in PHP5
			$xmldata = '<?xml version="1.0" encoding="' . $this->_p['encoding'] . '"?>' . $xmldata;

		$result = xml_parse($parser, $xmldata);
	}

	if (!$result)
		$this->error .= sprintf("it_xml error: %s at line %d", xml_error_string(xml_get_error_code($parser)), xml_get_current_line_number($parser));

	if ($this->error)
	{
		if ($this->_p['safety'] >= 2)
			it::fatal($this->error);
		else if ($this->_p['safety'] >= 1)
			it::error($this->error);

		if ($this->_p['factory'])
			$GLOBALS['IT_XML_ERROR'] = $this->error;
	}

	unset($this->_arrayforce, $this->_p['safety'], $this->_p['factory'], $this->_stack);
	xml_parser_free($parser);

	return empty($this->error);
}

function consume($p)
{
	return false;
}

/**
 * Utility function which recursively flattens container into array
 * @param with_attr if true, include attributes in result array
 * @return Array with key/values-pairs for vals and optionally attrs of sub-objects
 */
function flatten($with_attr = false)
{
	$result = $with_attr ? (array)$this->attr : array();

	foreach ($this->elements() as $key => $values)
	{
		if (is_array($values))
		{
			$result[$key] = array();

			foreach ($values as $value)
				$result[$key][] = isset($value->val) || !get_object_vars($value) ? $value->val : $value->flatten($with_attr);
		}
		else
			$result[$key] = isset($values->val) || !get_object_vars($values) ? $values->val : $values->flatten($with_attr);	# don' take recursion if val is set or object is empty
	}

	return $result;
}

# Strip namespace and convert extra characters to _
function _make_identifier($name)
{
	$id = preg_replace(array('/^.*:/', '/\W/'), array('', '_'), $name);
	return $this->_p['lowercase'] ? strtolower($id) : $id;
}

function start_element($parser, $name, $attrs)
{
	$name = $this->_p['prefix'] . $this->_make_identifier($name);

	if (!class_exists($name))
		eval("class $name extends it_xml {}");	# Extending the base class caused problems with tel_xmlentry

	if (!$this->_stack && !$this->_p['factory'])
		array_unshift($this->_stack, &$this);
	else
		array_unshift($this->_stack, new $name);

	if (!is_a($this->_stack[0], "it_xml"))
		$this->error .= "Class $name used in it_xml for tag $name does not extend it_xml: Name clash?\n";

	if ($attrs)
	{
		foreach ($attrs as $key => $val)
			$this->_stack[0]->attr[$this->_make_identifier($key)] = $val;
	}
}

function end_element($parser, $name)
{
	$name = $this->_make_identifier($name);

	if (!$this->_stack[0]->consume($this->_p))
	{
		if (is_array($this->_stack[1]->$name))
			array_push($this->_stack[1]->$name, &$this->_stack[0]);
		else if (isset($this->_stack[1]->$name))
		{
			if (is_a($this->_stack[1]->$name, "it_xml"))
				$this->_stack[1]->$name = array($this->_stack[1]->$name, &$this->_stack[0]);
			else
				$this->error .= "Variable $name used in it_xml for tag {$name} is already used in object: Name clash?\n";
		}
		else if (isset($this->_arrayforce[$name]))
			$this->_stack[1]->$name = array(&$this->_stack[0]);
		else
			$this->_stack[1]->$name =& $this->_stack[0];
	}

	$node = array_shift($this->_stack);

	if ($this->_p['factory'])
		$this->_root = $node;
}

function character_data($parser, $cdata)
{
	if (isset($this->_stack[0]->val) || (trim($cdata) !== ""))
		$this->_stack[0]->val .= $cdata;
}

/**
 * Convert XML object tree back to string representation
 * @param $p Associative array
 *	tag Name of root XML tag (otherwise determined by get_class)
 *	indent String to indent with (default: "  ")
 *	lineseparator String to start new line with (default: "\n")
 *	prefix String to prefix class names with (default: "")
 *	sort value true causes to_xml() to output elements sorted
 * @return XML string representation of this object
 */
function to_xml($p = array())
{
	$p += array(
		'tag' => substr(get_class($this), strlen($p['prefix'])),
		'indent' => "  ",
		'lineseparator' => "\n",
		'prefix' => "",
		'sort' => false,
		'stripempty' => false, # remove xml tags without content
	);

	$currenttag = $p['tag'];
	$tag = $p['nextindentation'] . "<$currenttag";

	if (empty($p['nextindentation']))
		$p['nextindentation'] = $p['lineseparator'];

	$currentindentation = $p['nextindentation'];
	$p['nextindentation'] .= $p['indent'];

	foreach ((array)$this->attr as $key => $value)
		$tag .= " $key=\"" . htmlspecialchars($value) . '"';

	$vars = get_object_vars($this);

	if ($p['sort'])
		ksort($vars);

	foreach ($vars as $key => $values)
	{
		$p['tag'] = $key;	# Manually set as PHP4 lowercases get_class()

		if (!preg_match('/^(_|attr$)/', $key))	# Skip implementation detail fields
		{
			if (is_array($values))
			{
				foreach ($values as $value)
				{
					if (is_a($value, "it_xml"))
					{
						$body .= $value->to_xml($p);
						$indentation = $currentindentation;
					}
				}
			}
			else if (is_object($values))
			{
				if (is_a($values, "it_xml"))
				{
					$body .= $values->to_xml($p);
					$indentation = $currentindentation;
				}
			}
			else if ($key == 'val')
				$body .= htmlspecialchars($values);
		}
	}

	return isset($body) ? "$tag>$body$indentation</$currenttag>" : ($p['stripempty'] ? "" : "$tag/>");
}

/**
 * Get array containing child elements (key value pairs)
 * @return Array containing child elements
 */
function elements()
{
	$result = array();

	foreach (get_object_vars($this) as $key => $value)
	{
		if (is_a($value, "it_xml") || (is_array($value) && is_a($value[0], "it_xml")))
			$result[$key] =& $this->$key;
	}

	return $result;
}

function error()
{
	return is_a($this, "it_xml") ? $this->error : $GLOBALS['IT_XML_ERROR'];
}

} 

?>