<?php
// a more general XML parser

require_once 'PEAR.php';

class XMLAttribute {
    
    var $name;
    var $value = null;

    function &XMLAttribute($name, $value) {
        $this->name = $name;
        $this->value = $value;
    }

    function get() {
        return $this->value;
    }

    function toString() {
        return "[{$this->name} = {$this->value}]";
    }
}

class XMLNode {

    var $name;
    var $attributes = array();
    var $content;
    var $children;
    var $parent = null;

    function &XMLNode($name, $attributes) {
        $this->name = $name;
        foreach ($attributes as $name=>$value) {
            $this->attributes[$name] = 
                new XMLAttribute($name, $value);
        }
        $this->children = array();
    }
    function setContent(&$data) {
        $this->content = $data;
    }

    function &addChild(&$child) {
        $child->setParent($this);
        $this->children[] =& $child;
        return $this->children[count($this->children) - 1];    
    }

    function setParent(&$parent) {
        $this->parent =& $parent;
    }

    function &getName() {
        return $this->name;
    }

    function &getParent() {
        return $this->parent;
    }

    function &getAttribute($attname) {
        if (array_keys_exists($attname, $this->attributes)) {
            return $this->attributes[$attname];
        }
    }

    function &getAttributes() {
        return $this->attributes;
    }
    
    function &getChildren() {
        return $this->children;
    }

    function &getContent() {
        return $this->content;
    }

    function toString($level=1) {
        $sep = '  ';
        $out = str_repeat($sep, $level - 1).
                "tag :: ".$this->getName()."\n";
        $out .= str_repeat($sep, $level)."attributes ::\n";
        foreach ($this->getAttributes() as $attr) {
            $out .= str_repeat($sep, $level + 1).
                    $attr->toString()."\n";
        }
        $out .= str_repeat($sep, $level).
                "content :: ".$this->getContent()."\n";
        foreach ($this->getChildren() as $child) {
            $out .= $child->toString($level + 1);
        }
        return $out;
    }
}

class XMLParser {

    var $parser;
    var $root;
    var $last = null;

    function XMLParser() {
        $this->parser = xml_parser_create();
        xml_set_object($this->parser, $this);
        xml_set_element_handler($this->parser, 'start', 'end');
        xml_set_character_data_handler($this->parser, 'cdata');
    }

    function parse($xml) {
        xml_parse($this->parser, $xml);
    }

    function start($parser, $name, $attrs) {
        $tag = trim($name);
        $node = new XMLNode($tag, $attrs);
        if (is_null($this->last)) {
            $this->root =& $node;
        } else {
            $this->last->addChild(&$node);
        }
        $this->last =& $node;
        
    }

    function end($parser, $name) {
        $this->last =& $this->last->parent;
    }

    function cdata($parser, $data) {
        if (!is_null($this->last))
            $this->last->setContent(trim($data));
    }

    function &getRoot() {
        return $this->root;
    }
}

$xml_file = 'presentations/slides/sdphp/data/sdphp_talk2.xml';
$xmldoc = implode('', file($xml_file));

$parser = new XMLParser();
$parser->parse($xmldoc);
$root = $parser->getRoot();

echo "<pre>\n".$root->toString()."</pre>\n";

?>