sarissa.js

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/**
 * ====================================================================
 * About
 * ====================================================================
 * Sarissa is an ECMAScript library acting as a cross-browser wrapper for native XML APIs.
 * The library supports Gecko based browsers like Mozilla and Firefox,
 * Internet Explorer (5.5+ with MSXML3.0+), Konqueror, Safari and a little of Opera
 * @version 0.9.6.1
 * @author: Manos Batsis, mailto: mbatsis at users full stop sourceforge full stop net
 * ====================================================================
 * Licence
 * ====================================================================
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 or
 * the GNU Lesser General Public License version 2.1 as published by
 * the Free Software Foundation (your choice between the two).
 *
 * 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 or GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * or GNU Lesser General Public License along with this program; if not,
 * write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 * or visit http://www.gnu.org
 *
 */
/**
 * <p>Sarissa is a utility class. Provides "static" methods for DOMDocument and 
 * XMLHTTP objects, DOM Node serializatrion to XML strings and other goodies.</p>
 * @constructor
 */
function Sarissa(){};
/** @private */
Sarissa.PARSED_OK = "Document contains no parsing errors";
/**
 * Tells you whether transformNode and transformNodeToObject are available. This functionality
 * is contained in sarissa_ieemu_xslt.js and is deprecated. If you want to control XSLT transformations
 * use the XSLTProcessor
 * @deprecated
 * @type boolean
 */
Sarissa.IS_ENABLED_TRANSFORM_NODE = false;
/**
 * tells you whether XMLHttpRequest (or equivalent) is available
 * @type boolean
 */
Sarissa.IS_ENABLED_XMLHTTP = false;
/**
 * tells you whether selectNodes/selectSingleNode is available
 * @type boolean
 */
Sarissa.IS_ENABLED_SELECT_NODES = false;
var _sarissa_iNsCounter = 0;
var _SARISSA_IEPREFIX4XSLPARAM = "";
var _SARISSA_HAS_DOM_IMPLEMENTATION = document.implementation && true;
var _SARISSA_HAS_DOM_CREATE_DOCUMENT = _SARISSA_HAS_DOM_IMPLEMENTATION && document.implementation.createDocument;
var _SARISSA_HAS_DOM_FEATURE = _SARISSA_HAS_DOM_IMPLEMENTATION && document.implementation.hasFeature;
var _SARISSA_IS_MOZ = _SARISSA_HAS_DOM_CREATE_DOCUMENT && _SARISSA_HAS_DOM_FEATURE;
var _SARISSA_IS_SAFARI = (navigator.userAgent && navigator.vendor && (navigator.userAgent.toLowerCase().indexOf("applewebkit") != -1 || navigator.vendor.indexOf("Apple") != -1));
var _SARISSA_IS_IE = document.all && window.ActiveXObject && navigator.userAgent.toLowerCase().indexOf("msie") > -1  && navigator.userAgent.toLowerCase().indexOf("opera") == -1;
if(!window.Node || !window.Node.ELEMENT_NODE){
    var Node = {ELEMENT_NODE: 1, ATTRIBUTE_NODE: 2, TEXT_NODE: 3, CDATA_SECTION_NODE: 4, ENTITY_REFERENCE_NODE: 5,  ENTITY_NODE: 6, PROCESSING_INSTRUCTION_NODE: 7, COMMENT_NODE: 8, DOCUMENT_NODE: 9, DOCUMENT_TYPE_NODE: 10, DOCUMENT_FRAGMENT_NODE: 11, NOTATION_NODE: 12};
};

// IE initialization
if(_SARISSA_IS_IE){
    // for XSLT parameter names, prefix needed by IE
    _SARISSA_IEPREFIX4XSLPARAM = "xsl:";
    // used to store the most recent ProgID available out of the above
    var _SARISSA_DOM_PROGID = "";
    var _SARISSA_XMLHTTP_PROGID = "";
    /**
     * Called when the Sarissa_xx.js file is parsed, to pick most recent
     * ProgIDs for IE, then gets destroyed.
     * @param idList an array of MSXML PROGIDs from which the most recent will be picked for a given object
     * @param enabledList an array of arrays where each array has two items; the index of the PROGID for which a certain feature is enabled
     */
    pickRecentProgID = function (idList, enabledList){
        // found progID flag
        var bFound = false;
        for(var i=0; i < idList.length && !bFound; i++){
            try{
                var oDoc = new ActiveXObject(idList[i]);
                o2Store = idList[i];
                bFound = true;
                for(var j=0;j<enabledList.length;j++)
                    if(i <= enabledList[j][1])
                        Sarissa["IS_ENABLED_"+enabledList[j][0]] = true;
            }catch (objException){
                // trap; try next progID
            };
        };
        if (!bFound)
            throw "Could not retreive a valid progID of Class: " + idList[idList.length-1]+". (original exception: "+e+")";
        idList = null;
        return o2Store;
    };
    // pick best available MSXML progIDs
    _SARISSA_DOM_PROGID = pickRecentProgID(["Msxml2.DOMDocument.5.0", "Msxml2.DOMDocument.4.0", "Msxml2.DOMDocument.3.0", "MSXML2.DOMDocument", "MSXML.DOMDocument", "Microsoft.XMLDOM"], [["SELECT_NODES", 2],["TRANSFORM_NODE", 2]]);
    _SARISSA_XMLHTTP_PROGID = pickRecentProgID(["Msxml2.XMLHTTP.5.0", "Msxml2.XMLHTTP.4.0", "MSXML2.XMLHTTP.3.0", "MSXML2.XMLHTTP", "Microsoft.XMLHTTP"], [["XMLHTTP", 4]]);
    _SARISSA_THREADEDDOM_PROGID = pickRecentProgID(["Msxml2.FreeThreadedDOMDocument.5.0", "MSXML2.FreeThreadedDOMDocument.4.0", "MSXML2.FreeThreadedDOMDocument.3.0"]);
    _SARISSA_XSLTEMPLATE_PROGID = pickRecentProgID(["Msxml2.XSLTemplate.5.0", "Msxml2.XSLTemplate.4.0", "MSXML2.XSLTemplate.3.0"], [["XSLTPROC", 2]]);
    // we dont need this anymore
    pickRecentProgID = null;
    //============================================
    // Factory methods (IE)
    //============================================
    // see non-IE version
    Sarissa.getDomDocument = function(sUri, sName){
        var oDoc = new ActiveXObject(_SARISSA_DOM_PROGID);
        // if a root tag name was provided, we need to load it in the DOM
        // object
        if (sName){
            // if needed, create an artifical namespace prefix the way Moz
            // does
            if (sUri){
                oDoc.loadXML("<a" + _sarissa_iNsCounter + ":" + sName + " xmlns:a" + _sarissa_iNsCounter + "=\"" + sUri + "\" />");
                // don't use the same prefix again
                ++_sarissa_iNsCounter;
            }
            else
                oDoc.loadXML("<" + sName + "/>");
        };
        return oDoc;
    };
    // see non-IE version   
    Sarissa.getParseErrorText = function (oDoc) {
        var parseErrorText = Sarissa.PARSED_OK;
        if(oDoc.parseError != 0){
            parseErrorText = "XML Parsing Error: " + oDoc.parseError.reason + 
                "\nLocation: " + oDoc.parseError.url + 
                "\nLine Number " + oDoc.parseError.line + ", Column " + 
                oDoc.parseError.linepos + 
                ":\n" + oDoc.parseError.srcText +
                "\n";
            for(var i = 0;  i < oDoc.parseError.linepos;i++){
                parseErrorText += "-";
            };
            parseErrorText +=  "^\n";
        };
        return parseErrorText;
    };
    // see non-IE version
    Sarissa.setXpathNamespaces = function(oDoc, sNsSet) {
        oDoc.setProperty("SelectionLanguage", "XPath");
        oDoc.setProperty("SelectionNamespaces", sNsSet);
    };   
    /**
     * Basic implementation of Mozilla's XSLTProcessor for IE. 
     * Reuses the same XSLT stylesheet for multiple transforms
     * @constructor
     */
    XSLTProcessor = function(){
        this.template = new ActiveXObject(_SARISSA_XSLTEMPLATE_PROGID);
        this.processor = null;
    };
    /**
     * Impoprts the given XSLT DOM and compiles it to a reusable transform
     * @argument xslDoc The XSLT DOMDocument to import
     */
    XSLTProcessor.prototype.importStylesheet = function(xslDoc){
        // convert stylesheet to free threaded
        var converted = new ActiveXObject(_SARISSA_THREADEDDOM_PROGID); 
        converted.loadXML(xslDoc.xml);
        this.template.stylesheet = converted;
        this.processor = this.template.createProcessor();
        // (re)set default param values
        this.paramsSet = new Array();
    };
    /**
     * Transform the given XML DOM
     * @argument sourceDoc The XML DOMDocument to transform
     * @return The transformation result as a DOM Document
     */
    XSLTProcessor.prototype.transformToDocument = function(sourceDoc){
        this.processor.input = sourceDoc;
        var outDoc = new ActiveXObject(_SARISSA_DOM_PROGID);
        this.processor.output = outDoc; 
        this.processor.transform();
        return outDoc;
    };
    /**
     * Set global XSLT parameter of the imported stylesheet
     * @argument nsURI The parameter namespace URI
     * @argument name The parameter base name
     * @argument value The new parameter value
     */
    XSLTProcessor.prototype.setParameter = function(nsURI, name, value){
        /* nsURI is optional but cannot be null */
        if(nsURI){
            this.processor.addParameter(name, value, nsURI);
        }else{
            this.processor.addParameter(name, value);
        };
        /* update updated params for getParameter */
        if(!this.paramsSet[""+nsURI]){
            this.paramsSet[""+nsURI] = new Array();
        };
        this.paramsSet[""+nsURI][name] = value;
    };
    /**
     * Gets a parameter if previously set by setParameter. Returns null
     * otherwise
     * @argument name The parameter base name
     * @argument value The new parameter value
     * @return The parameter value if reviously set by setParameter, null otherwise
     */
    XSLTProcessor.prototype.getParameter = function(nsURI, name){
        nsURI = nsURI || "";
        if(nsURI in this.paramsSet && name in this.paramsSet[nsURI]){
            return this.paramsSet[nsURI][name];
        }else{
            return null;
        };
    };
}
else{ /* end IE initialization, try to deal with real browsers now ;-) */
    if(_SARISSA_HAS_DOM_CREATE_DOCUMENT){
        /**
         * <p>Ensures the document was loaded correctly, otherwise sets the
         * parseError to -1 to indicate something went wrong. Internal use</p>
         * @private
         */
        Sarissa.__handleLoad__ = function(oDoc){
            if (!oDoc.documentElement || oDoc.documentElement.tagName == "parsererror")
                oDoc.parseError = -1;
            Sarissa.__setReadyState__(oDoc, 4);
        };
        /**
        * <p>Attached by an event handler to the load event. Internal use.</p>
        * @private
        */
        _sarissa_XMLDocument_onload = function(){
            Sarissa.__handleLoad__(this);
        };
        /**
         * <p>Sets the readyState property of the given DOM Document object.
         * Internal use.</p>
         * @private
         * @argument oDoc the DOM Document object to fire the
         *          readystatechange event
         * @argument iReadyState the number to change the readystate property to
         */
        Sarissa.__setReadyState__ = function(oDoc, iReadyState){
            oDoc.readyState = iReadyState;
            if (oDoc.onreadystatechange != null && typeof oDoc.onreadystatechange == "function")
                oDoc.onreadystatechange();
        };
        Sarissa.getDomDocument = function(sUri, sName){
            var oDoc = document.implementation.createDocument(sUri?sUri:"", sName?sName:"", null);
            oDoc.addEventListener("load", _sarissa_XMLDocument_onload, false);
            return oDoc;
        };
        if(window.XMLDocument){
            /**
            * <p>Emulate IE's onreadystatechange attribute</p>
            */
            XMLDocument.prototype.onreadystatechange = null;
            /**
            * <p>Emulates IE's readyState property, which always gives an integer from 0 to 4:</p>
            * <ul><li>1 == LOADING,</li>
            * <li>2 == LOADED,</li>
            * <li>3 == INTERACTIVE,</li>
            * <li>4 == COMPLETED</li></ul>
            */
            XMLDocument.prototype.readyState = 0;
            /**
            * <p>Emulate IE's parseError attribute</p>
            */
            XMLDocument.prototype.parseError = 0;

            // NOTE: setting async to false will only work with documents
            // called over HTTP (meaning a server), not the local file system,
            // unless you are using Moz 1.4+.
            // BTW the try>catch block is for 1.4; I haven't found a way to check if
            // the property is implemented without
            // causing an error and I dont want to use user agent stuff for that...
            var _SARISSA_SYNC_NON_IMPLEMENTED = false;// ("async" in XMLDocument.prototype) ? false: true;
            /**
            * <p>Keeps a handle to the original load() method. Internal use and only
            * if Mozilla version is lower than 1.4</p>
            * @private
            */
            XMLDocument.prototype._sarissa_load = XMLDocument.prototype.load;

            /**
            * <p>Overrides the original load method to provide synchronous loading for
            * Mozilla versions prior to 1.4, using an XMLHttpRequest object (if
            * async is set to false)</p>
            * @returns the DOM Object as it was before the load() call (may be  empty)
            */
            XMLDocument.prototype.load = function(sURI) {
                var oDoc = document.implementation.createDocument("", "", null);
                Sarissa.copyChildNodes(this, oDoc);
                this.parseError = 0;
                Sarissa.__setReadyState__(this, 1);
                try {
                    if(this.async == false && _SARISSA_SYNC_NON_IMPLEMENTED) {
                        var tmp = new XMLHttpRequest();
                        tmp.open("GET", sURI, false);
                        tmp.send(null);
                        Sarissa.__setReadyState__(this, 2);
                        Sarissa.copyChildNodes(tmp.responseXML, this);
                        Sarissa.__setReadyState__(this, 3);
                    }
                    else {
                        this._sarissa_load(sURI);
                    };
                }
                catch (objException) {
                    this.parseError = -1;
                }
                finally {
                    if(this.async == false){
                        Sarissa.__handleLoad__(this);
                    };
                };
                return oDoc;
            };