<?php

// $Id: saxparser.php 10761 2013-01-11 18:39:56Z trabis $

/*******************************************************************************

Location: <strong>xml/SaxParser.class</strong><br>

<br>

Provides basic functionality to read and parse XML documents.  Subclasses

must implement all the their custom handlers by using add* function methods.

They may also use the handle*() methods to parse a specific XML begin and end

tags, but this is not recommended as it is more difficult.<br>

<br>

Copyright &copy; 2001 eXtremePHP.  All rights reserved.<br>

<br>

@author Ken Egervari<br>

 *******************************************************************************/



class SaxParser

{

    var $level;

    var $parser;



    var $isCaseFolding;

    var $targetEncoding;



    /* Custom Handler Variables */

    var $tagHandlers = array();



    /* Tag stack */

    var $tags = array();



    /* Xml Source Input */

    var $xmlInput;



    var $errors = array();



    /**

     * Creates a SaxParser object using a FileInput to represent the stream

     * of XML data to parse.  Use the static methods createFileInput or

     * createStringInput to construct xml input source objects to supply

     * to the constructor, or the implementor can construct them individually.

     *

     * @param $input

     */

    function __construct(&$input)

    {

        $this->level = 0;

        $this->parser = xml_parser_create('UTF-8');

        xml_set_object($this->parser, $this);

        $this->input = $input;

        $this->setCaseFolding(false);

        $this->useUtfEncoding();

        xml_set_element_handler($this->parser, 'handleBeginElement', 'handleEndElement');

        xml_set_character_data_handler($this->parser, 'handleCharacterData');

        xml_set_processing_instruction_handler($this->parser, 'handleProcessingInstruction');

        xml_set_default_handler($this->parser, 'handleDefault');

        xml_set_unparsed_entity_decl_handler($this->parser, 'handleUnparsedEntityDecl');

        xml_set_notation_decl_handler($this->parser, 'handleNotationDecl');

        xml_set_external_entity_ref_handler($this->parser, 'handleExternalEntityRef');

    }



    /*---------------------------------------------------------------------------

        Property Methods

    ---------------------------------------------------------------------------*/



    function getCurrentLevel()

    {

        return $this->level;

    }



    /****************************************************************************

     * @param $isCaseFolding

     * @returns void

     ****************************************************************************/

    function setCaseFolding($isCaseFolding)

    {

        assert(is_bool($isCaseFolding));



        $this->isCaseFolding = $isCaseFolding;

        xml_parser_set_option($this->parser, XML_OPTION_CASE_FOLDING, $this->isCaseFolding);

    }



    /****************************************************************************

     * @returns void

     ****************************************************************************/

    function useIsoEncoding()

    {

        $this->targetEncoding = 'ISO-8859-1';

        xml_parser_set_option($this->parser, XML_OPTION_TARGET_ENCODING, $this->targetEncoding);

    }



    /****************************************************************************

     * @returns void

     ****************************************************************************/

    function useAsciiEncoding()

    {

        $this->targetEncoding = 'US-ASCII';

        xml_parser_set_option($this->parser, XML_OPTION_TARGET_ENCODING, $this->targetEncoding);

    }



    /****************************************************************************

     * @returns void

     ****************************************************************************/

    function useUtfEncoding()

    {

        $this->targetEncoding = 'UTF-8';

        xml_parser_set_option($this->parser, XML_OPTION_TARGET_ENCODING, $this->targetEncoding);

    }



    /****************************************************************************

    Returns the name of the xml tag being parsed

     * @returns string

     ****************************************************************************/

    function getCurrentTag()

    {

        return $this->tags[count($this->tags) - 1];

    }



    function getParentTag()

    {

        if (isset($this->tags[count($this->tags) - 2])) {

            return $this->tags[count($this->tags) - 2];

        }

        return false;

    }





    /*---------------------------------------------------------------------------

        Parser methods

    ---------------------------------------------------------------------------*/



    /**

     * @return bool

     */

    function parse()

    {

        if (!is_resource($this->input)) {

            if (!xml_parse($this->parser, $this->input)) {

                $this->setErrors($this->getXmlError());

                return false;

            }

            //if (!$fp = fopen($this->input, 'r')) {

            //    $this->setErrors('Could not open file: '.$this->input);

            //    return false;

            //}

        } else {

            while ($data = fread($this->input, 4096)) {

                if (!xml_parse($this->parser, str_replace("'", "&apos;", $data), feof($this->input))) {

                    $this->setErrors($this->getXmlError());

                    fclose($this->input);

                    return false;

                }

            }

            fclose($this->input);

        }

        return true;

    }



    /****************************************************************************

     * @returns void

     ****************************************************************************/

    function free()

    {

        xml_parser_free($this->parser);



        if (!method_exists($this, '__destruct')) {

            unset($this);

        } else {

            $this->__destruct();

        }

    }



    /**

     * @private

     * @return string

     */

    function getXmlError()

    {

        return sprintf("XmlParse error: %s at line %d", xml_error_string(xml_get_error_code($this->parser)), xml_get_current_line_number($this->parser));

    }



    /*---------------------------------------------------------------------------

        Custom Handler Methods

    ---------------------------------------------------------------------------*/



    /**

     * Adds a callback function to be called when a tag is encountered.<br>

     * @param XmlTagHandler $tagHandler

     * @return void

     */

    function addTagHandler(XmlTagHandler &$tagHandler)

    {

        $name = $tagHandler->getName();

        if (is_array($name)) {

            foreach ($name as $n) {

                $this->tagHandlers[$n] = $tagHandler;

            }

        } else {

            $this->tagHandlers[$name] = $tagHandler;

        }

    }





    /*---------------------------------------------------------------------------

        Private Handler Methods

    ---------------------------------------------------------------------------*/



    /****************************************************************************

    Callback function that executes whenever a the start of a tag

    occurs when being parsed.

     * @param $parser int.  The handle to the parser.

     * @param $tagName string.  The name of the tag currently being parsed.

     * @param $attributesArray attay.  The list of attributes associated with

    the tag.

     * @private

     * @returns void

     ****************************************************************************/

    function handleBeginElement($parser, $tagName, $attributesArray)

    {

        array_push($this->tags, $tagName);

        $this->level++;

        if (isset($this->tagHandlers[$tagName]) && is_subclass_of($this->tagHandlers[$tagName], 'xmltaghandler')) {

            $this->tagHandlers[$tagName]->handleBeginElement($this, $attributesArray);

        } else {

            $this->handleBeginElementDefault($parser, $tagName, $attributesArray);

        }

    }



    /****************************************************************************

    Callback function that executes whenever the end of a tag

    occurs when being parsed.

     * @param $parser int.  The handle to the parser.

     * @param $tagName string.  The name of the tag currently being parsed.

     * @private

     * @returns void

     ****************************************************************************/

    function handleEndElement($parser, $tagName)

    {

        array_pop($this->tags);

        if (isset($this->tagHandlers[$tagName]) && is_subclass_of($this->tagHandlers[$tagName], 'xmltaghandler')) {

            $this->tagHandlers[$tagName]->handleEndElement($this);

        } else {

            $this->handleEndElementDefault($parser, $tagName);

        }

        $this->level--;

    }



    /****************************************************************************

    Callback function that executes whenever character data is encountered

    while being parsed.

     * @param $parser int.  The handle to the parser.

     * @param $data string.  Character data inside the tag

     * @returns void

     ****************************************************************************/

    function handleCharacterData($parser, $data)

    {

        $tagHandler = isset($this->tagHandlers[$this->getCurrentTag()]) ? $this->tagHandlers[$this->getCurrentTag()] : null;

        if (null != $tagHandler && is_subclass_of($tagHandler, 'xmltaghandler')) {

            $tagHandler->handleCharacterData($this, $data);

        } else {

            $this->handleCharacterDataDefault($parser, $data);

        }

    }



    /**

     * @param $parser int.  The handle to the parser.

     * @param $target

     * @param $data

     * @return void

     */

    function handleProcessingInstruction($parser, &$target, &$data)

    {

        //        if($target == 'php') {

        //            eval($data);

        //        }

    }



    /**

     * @param $parser

     * @param $data

     * @return void

     */

    function handleDefault($parser, $data)

    {



    }



    /**

     * @param $parser

     * @param $entityName

     * @param $base

     * @param $systemId

     * @param $publicId

     * @param $notationName

     * @return void

     */

    function handleUnparsedEntityDecl($parser, $entityName, $base, $systemId, $publicId, $notationName)

    {



    }



    /**

     * @param $parser

     * @param $notationName

     * @param $base

     * @param $systemId

     * @param $publicId

     * @return void

     */

    function handleNotationDecl($parser, $notationName, $base, $systemId, $publicId)

    {



    }



    /**

     * @param $parser

     * @param $openEntityNames

     * @param $base

     * @param $systemId

     * @param $publicId

     * @return void

     */

    function handleExternalEntityRef($parser, $openEntityNames, $base, $systemId, $publicId)

    {



    }



    /**

     * The default tag handler method for a tag with no handler

     *

     * @param $parser

     * @param $tagName

     * @param $attributesArray

     * @return void

     */

    function handleBeginElementDefault($parser, $tagName, $attributesArray)

    {

    }



    /**

     * The default tag handler method for a tag with no handler

     *

     * @param $parser

     * @param $tagName

     * @return void

     */

    function handleEndElementDefault($parser, $tagName)

    {

    }



    /**

     * The default tag handler method for a tag with no handler

     *

     * @abstract

     *

     * @param $parser

     * @param $data

     * @return void

     */

    function handleCharacterDataDefault($parser, $data)

    {

    }



    /**

     * Sets error messages

     *

     * @param    $error    string    an error message

     */

    function setErrors($error)

    {

        $this->errors[] = trim($error);

    }



    /**

     * Gets all the error messages

     *

     * @param    $ashtml    bool    return as html?

     * @return    mixed

     */

    function getErrors($ashtml = true)

    {

        if (!$ashtml) {

            return $this->errors;

        } else {

            $ret = '';

            if (count($this->errors) > 0) {

                foreach ($this->errors as $error) {

                    $ret .= $error . '<br />';

                }

            }

            return $ret;

        }

    }

}