<?php
//
// +----------------------------------------------------------------------+
// | PEAR :: XML_Tree                                                     |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2003 The PHP Group                                |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.02 of the PHP license,      |
// | that is bundled with this package in the file LICENSE, and is        |
// | available at through the world-wide-web at                           |
// | http://www.php.net/license/2_02.txt.                                 |
// | If you did not receive a copy of the PHP license and are unable to   |
// | obtain it through the world-wide-web, please send a note to          |
// | license@php.net so we can mail you a copy immediately.               |
// +----------------------------------------------------------------------+
// | Authors: Bernd Römer <berndr@bonn.edu>                               |
// |          Sebastian Bergmann <sb@sebastian-bergmann.de>               |
// |          Tomas V.V.Cox <cox@idecnet.com>                             |
// |          Michele Manzato <michele.manzato@verona.miz.it>             |
// +----------------------------------------------------------------------+
//
// $Id$
//

require_once 'XML/Parser.php';
require_once 'XML/Tree/Node.php';

/**
 * PEAR::XML_Tree
 *
 * Purpose
 *
 *    Allows for the building of XML data structures
 *    using a tree representation, without the need
 *    for an extension like DOMXML.
 *
 * Example
 *
 *    $tree  = new XML_Tree;
 *    $root =& $tree->addRoot('root');
 *    $foo  =& $root->addChild('foo');
 *
 *    $tree->dump(true);
 *
 * @author  Bernd Römer <berndr@bonn.edu>
 * @package XML
 * @version $Version$ - 1.0
 */
class XML_Tree extends XML_Parser
{
    /**
     * File Handle
     *
     * @var  resource
     */
    var $file = NULL;

    /**
     * Filename from which the XML_Tree was read
     *
     * @var  string
     */
    var $filename = '';

    /**
     * Namespace
     *
     * @var  array
     */
    var $namespace = array();

    /**
     * Root node of the XML tree
     *
     * @var  object XML_Tree_Node
     */
    var $root = NULL;

    /**
     * XML Version
     *
     * @var  string
     */
    var $version = '1.0';

    /**
     * Whether to encapsulate the all CDATA in a <![CDATA[]]> section
     *
     * @var boolean
     */

    var $use_cdata_sections = false;

    /**
     * Constructor
     *
     * @param  string  filename  Filename where to read the XML
     * @param  string  version   XML Version to apply
     */
    function XML_Tree($filename = '', $version = '1.0')
    {
        $this->filename = $filename;
        $this->version  = $version;
    }

    /**
     * Use <![CDATA[]]> for all CDATA sections
     *
     * @return void
     */

    function useCdataSections()
    {
        $this->use_cdata_sections = true;
    }

    /**
     * Gets the root node
     *
     * @return object    Root XML_Tree_Node, or PEAR_Error if there isn't any root node.
     *
     * @access public
     */
    function &getRoot()
    {
        if (!is_null($this->root)) {
            return $this->root;
        }
        return $this->raiseError("No root");
    }

    /**
     * Sets the root node of the XML tree.
     *
     * @param  string    name        Name of root element
     *
     * @return object XML_Tree_Node   Reference to the newly created root node
     * @access public
     */
    function &addRoot($name, $content = '', $attributes = array(), $lineno = null)
    {
        $this->root = new XML_Tree_Node($name, $content, $attributes, $lineno);
        return $this->root;
    }

    /**
     * Inserts a child/tree (child) into tree ($path,$pos) and maintains
     * namespace integrity
     *
     * @param mixed      path            Path to parent node to add child (see
     *                                   getNodeAt() for format)
     * @param integer    pos             Position where to insert the new child.
     *                                   0 < means |$pos| elements before the end,
     *                                   e.g. -1 appends as last child.
     * @param mixed      child           Child to insert (XML_Tree or XML_Tree_Node),
     *                                   or name of child node
     * @param string     content         Content (text) for the new node (only if
     *                                   $child is the node name)
     * @param array      attributes      Attribute-hash for new node
     *
     * @return object Reference to the inserted child (node), or PEAR_Error upon error
     * @access public
     * @see getNodeAt()
     */
    function &insertChild($path, $pos, $child, $content = '', $attributes = array())
    {
        $parent =& $this->getNodeAt($path);
        if (PEAR::isError($parent)) {
            return $parent;
        }

        $x =& $parent->insertChild(null, $pos, $child, $content, $attributes);

        if (!PEAR::isError($x)) {
        // update namespace to maintain namespace integrity
            $count = count($path);
            foreach ($this->namespace as $key => $val) {
                if ((array_slice($val,0,$count)==$path) && ($val[$count]>=$pos)) {
                    $this->namespace[$key][$count]++;
                }
            }
        }
        return $x;
    }

    /**
     * Removes a child node from tree and maintains namespace integrity
     *
     * @param array      path        Path to the parent of child to remove (see
     *                               getNodeAt() for format)
     * @param integer    pos         Position of child in parent children-list
     *                               0 < means |$pos| elements before the end,
     *                               e.g. -1 removes the last child.
     *
     * @return object    Parent XML_Tree_Node whose child was removed, or PEAR_Error upon error
     * @access public
     * @see getNodeAt()
     */
    function &removeChild($path, $pos)
    {
        $parent =& $this->getNodeAt($path);
        if (PEAR::isError($parent)) {
            return $parent;
        }

        $x =& $parent->removeChild($pos);

        if (!PEAR::isError($x)) {
            // Update namespace to maintain namespace integrity
            $count=count($path);
            foreach($this->namespace as $key => $val) {
                if (array_slice($val,0,$count)==$path) {
                    if ($val[$count]==$pos) {
                        unset($this->namespace[$key]); break;
                    }
                    if ($val[$count]>$pos) {
                        $this->namespace[$key][$count]--;
                    }
                }
            }
        }

        return $x;
    }

    /**
     * Maps a XML file to a XML_Tree
     *
     * @return mixed The XML tree root (an XML_Tree_Node), or PEAR_Error upon error.
     * @access public
     */
    function &getTreeFromFile ()
    {
        $this->folding = false;
        $this->XML_Parser(null, 'event');
        $err = $this->setInputFile($this->filename);
        if (PEAR::isError($err)) {
            return $err;
        }
        $this->cdata = null;
        $err = $this->parse();
        if (PEAR::isError($err)) {
            return $err;
        }
        return $this->root;
    }

    /**
     * Maps an XML string to an XML_Tree.
     *
     * @return mixed The XML tree root (an XML_Tree_Node), or PEAR_Error upon error.
     * @access public
     */
    function &getTreeFromString($str)
    {
        $this->i = null;
        $this->folding = false;
        $this->XML_Parser(null, 'event');
        $this->cdata = null;
        $err = $this->parseString($str);
        if (PEAR::isError($err)) {
            return $err;
        }
        return $this->root;
    }

    /**
     * Handler for the xml-data
     * Used by XML_Parser::XML_Parser() when parsing an XML stream.
     *
     * @param mixed  xp          ignored
     * @param string elem        name of the element
     * @param array  attribs     attributes for the generated node
     *
     * @access private
     */
    function startHandler($xp, $elem, &$attribs)
    {
        $lineno = xml_get_current_line_number($xp);
        // root elem
        if (!isset($this->i)) {
            $this->obj1 =& $this->addRoot($elem, null, $attribs, $lineno);
            $this->i = 2;
        } else {
            // mixed contents
            if (!empty($this->cdata)) {
                $parent_id = 'obj' . ($this->i - 1);
                $parent    =& $this->$parent_id;
                $parent->children[] = &new XML_Tree_Node(null, $this->cdata, null, $lineno);
            }
            $obj_id = 'obj' . $this->i++;
            $this->$obj_id = &new XML_Tree_Node($elem, null, $attribs, $lineno);
        }
        $this->cdata = null;
        return null;
    }

    /**
     * Handler for the xml-data
     * Used by XML_Parser::XML_Parser() when parsing an XML stream.
     *
     * @param mixed  xp          ignored
     * @param string elem        name of the element
     *
     * @access private
     */
    function endHandler($xp, $elem)
    {
        $this->i--;
        if ($this->i > 1) {
            $obj_id = 'obj' . $this->i;
            // recover the node created in StartHandler
            $node   =& $this->$obj_id;
            // mixed contents
            if (count($node->children) > 0) {
                if (trim($this->cdata) != '') {
                    $node->children[] = &new XML_Tree_Node(null, $this->cdata);
                }
            } else {
                $node->setContent($this->cdata);
            }
            $parent_id = 'obj' . ($this->i - 1);
            $parent    =& $this->$parent_id;
            // attach the node to its parent node children array
            $parent->children[] = $node;
        } else {
            $node =& $this->obj1;
            if (count($node->children) > 0) {
                if (trim($this->cdata)) {
                    $node->children[] = &new XML_Tree_Node(null, $this->cdata);
                }
            } else {
                $node->setContent($this->cdata);
            }
        }
        $this->cdata = null;
        return null;
    }

    /**
     * The xml character data handler
     * Used by XML_Parser::XML_Parser() when parsing an XML stream.
     *
     * @param mixed  xp          ignored
     * @param string data        PCDATA between tags
     *
     * @access private
     */
    function cdataHandler($xp, $data)
    {
        $this->cdata .= $data;
    }

    /**
     * Get a copy of this tree by cloning and all of its nodes, recursively.
     *
     * @return object XML_Tree copy of this node.
     * @access public
     */
    function cloneTree()
    {
        $clone = new XML_Tree($this->filename, $this->version);
        if (!is_null($this->root)) {
            $clone->root = $this->root->cloneTree();
        }

        // clone all other vars
        $temp = get_object_vars($this);
        foreach($temp as $varname => $value) {
            if (!in_array($varname,array('filename','version','root'))) {
                $clone->$varname=$value;
            }
        }
        return $clone;
    }

    /**
     * Print text representation of XML tree.
     *
     * @param bool xmlHeader     if true then generate also the leading XML
     *                           'Content-type' header directive, e.g. for
     *                           direct output to a web page.
     *
     * @access public
     */
    function dump($xmlHeader = false)
    {
        if ($xmlHeader) {
            header('Content-type: text/xml');
        }
        echo $this->get($this->use_cdata_sections);
    }

    /**
     * Get text representation of XML tree.
     *
     * @return string  Text (XML) representation of the tree
     * @access public
     */
    function &get()
    {
        $out = '<?xml version="' . $this->version . "\"?>\n";

        if (!is_null($this->root))
        {
            if(!is_object($this->root) || (strtolower(get_class($this->root)) != 'xml_tree_node'))
            return $this->raiseError("Bad XML root node");
            $out .= $this->root->get($this->use_cdata_sections);
        }
        return $out;
    }

    /**
     * Get current namespace.
     *
     * @param  string  name  namespace
     * @return string
     *
     * @access public
     */
    function &getName($name) {
        return $this->root->getElement($this->namespace[$name]);
    }

    /**
     * Get A Nodes Namespace
     */

    function getNodeNamespace(&$node) {
        $name_parts = explode(':',$node->name);
        if (sizeof($name_parts) > 1) {
            $namespace = $name_parts[0];
        } else {
            $namespace = '';
        }

        if (isset($node->namespace[$namespace])) {
            return $node->namespace[$namespace];
        } elseif (isset($this->root->namespace[$namespace])) {
            return $this->root->namespace[$namespace];
        } else {
            return '';
        }
    }

    /**
     * Get a reference to a node. Node is searched by its 'path'.
     *
     * @param mixed  path  Path to node. Can be either a string (slash-separated
     *                     children names) or an array (sequence of children names) both
     *                     of them starting from node. Note that the first name in sequence
     *                     must be the name of the document root.
     * @return object    Reference to the XML_Tree_Node found, or PEAR_Error if
     *                   the path does not exist. If more than one element matches
     *                   then only the first match is returned.
     * @access public
     */
    function &getNodeAt($path)
    {
        if (is_null($this->root)){
            return $this->raiseError("XML_Tree hasn't a root node");
        }
        if (is_string($path))
            $path = explode("/", $path);
        if (sizeof($path) == 0) {
            return $this->raiseError("Path to node is empty");
        }
        $path1 = $path;
        $rootName = array_shift($path1);
        if ($this->root->name != $rootName) {
            return $this->raiseError("Path does not match the document root");
        }
        $x =& $this->root->getNodeAt($path1);
        if (!PEAR::isError($x)) {
            return $x;
        }
        // No node with that name found
        return $this->raiseError("Bad path to node: [".implode('/', $path)."]");
    }

    /**
     * Gets all children that match a given tag name.
     *
     * @param  string    Tag name
     *
     * @return array     An array of Node objects of the children found,
     *                   an empty array if none
     * @access public
     * @author Pierre-Alain Joye <paj@pearfr.org>
     */
    function &getElementsByTagName($tagName)
    {
        if (empty($tagName)) {
            return $this->raiseError('Empty tag name');
        }
        $result = array();
        foreach ($this->root->children as $child) {
            if ($child->name == $tagName) {
                $result[] = $child;
            }
        }
        return $result;
    }

    /**
     * Gets all children that match a given tag name from node
     *
     * @param string $tagName Tag Name
     * @param object &$node Node in which to search
     * @see XML_Tree::getElementsByTagName()
     * @return array An array of found Node objects, empty is none found.
     * @access public
     * @author Pierre-Alain Joye <paj@pearfr.org>
     * @author Davey Shafik <davey@php.net>
     */

    function &getElementsByTagNameFromNode($tagName, &$node)
    {
        if (empty($tagName)) {
            return $this->raiseError('Empty tag name');
        }
        $result = array();
        foreach ($node->children as $child) {
            if ($child->name == $tagName) {
                $result[] = $child;
            }
        }
        return $result;
    }


    /**
     * Checks if $name is a valid XML name
     *
     * @static
     * @param string $name String to check for validity as an XML Name
     * @return mixed
     */

    function isValidName($name, $type) {
        if (trim($name) == '') {
            return true;
        }
        
        //  check for invalid starting character
        if (!preg_match("/[[:alpha:]_]/", $name{0})) {
            return new PEAR_Error( ucfirst($type) . " ('$name') has an invalid name, an XML name may only start with a letter or underscore");
        }

        if (!preg_match("/^([a-zA-Z_]([a-zA-Z0-9_\-\.]*)?:)?[a-zA-Z_]([a-zA-Z0-9_\-\.]+)?$/", $name)) {
            return new PEAR_Error( ucfirst($type) . " ('$name') has an invalid name, an XML name may only contain alphanumeric chars, period, hyphen, colon and underscores");
        }

        return true;
    }
}
?>