/*
    Copyright 2006 Christian Gross http://www.devspace.com
    From the book Ajax Patterns and Best Practices

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/
function GenerateUniqueIdentifer() {
    var splitLocation = location.href.split( "#");
    return splitLocation[ 0] + Math.floor( Math.random() * 10000);
}


var StateNavigatorHash = {
    username: null,
    password: null,
    postURL: null,

    constPageStateHeader : "X-Page-State",
    constResourceStateContentType : "application/xml",
    constURLStateIdentifier : "/state",
    
    constStateTag : "state",
    constHtmlPageStateTag : "html-page",

    onLoadState : function( status, responseXML) { },
    extractFormData : function( element, objData) {
        if( element.nodeType == 1) {
            if( element.nodeName == "form") {
                objData.formId = element.attributes.getNamedItem( "id").nodeValue;
                objData.formNode = document.forms[ objData.formId];
            }
            else if( element.nodeName == "element") {
                if( objData.formNode != null) {
                    var elementIdentifier = element.attributes.getNamedItem( "id").nodeValue;
                    if( element.childNodes[ 0] != null) {
                        var elementValue = element.childNodes[ 0].nodeValue;
                        objData.formNode.elements[ elementIdentifier].value = elementValue;
                    }
                }
            }
        }
    },
    loadForm : function( xmlState) {
        this.verify = this.extractFormData;
        var objData = new Object();
        XMLIterateElements( this, objData, xmlState);
    },
    extractUserData : function( element, objData) {
        if( element.nodeType == 1) {
            if( element.nodeName == this.constHtmlPageStateTag) {
                objData.foundElement = element;
            }
        }
    },
    loadState : function() {
        if( location.hash != null) {
            var asynch = new Asynchronous();
            var thisReference = this;
            asynch.openCallback = function( xmlhttp) {
                if( location.hash.length == 0) {
                    xmlhttp.setRequestHeader( thisReference.constPageStateHeader, "none");
                }
                else {
                    xmlhttp.setRequestHeader( thisReference.constPageStateHeader, location.hash.slice(1));
                }
                xmlhttp.setRequestHeader( "Accept", thisReference.constResourceStateContentType);
            }
            var xmlhttp = asynch._xmlhttp;
            asynch.complete = function( status, statusText, responseText, responseXML) {
                try {
                    eval( "var stateResponse = " + responseText);
                    thisReference.onLoadState( status, stateResponse);
                    location.replace( location.pathname + "#" + xmlhttp.getResponseHeader( thisReference.constPageStateHeader));
                }
                catch( e) { 
                    //window.alert( e.description);
                }
            }
            asynch.username = this.username;
            asynch.password = this.password;
            var splitLocation = location.href.split( "#");
            asynch.get( splitLocation[ 0] + this.constURLStateIdentifier);
        }
    },
    extractLink : function( element, objData) {
        if( element.nodeType == 1) {
            if( element.nodeName == "link") {
                var attr = element.attributes.getNamedItem( "id");
                if( attr.nodeValue == "redirect") {
                    objData.redirectURL = element.attributes.getNamedItem("href").nodeValue;
                }
            }
        }
    },
    onSaveState : function() {
        return "";
    },
    saveForm : function( form) { 
        this.postURL = form.action;
        var buffer = "";
        buffer += "<form id=\"" + form.name + "\" >\n";
        for( var i = 0; i < form.elements.length; i++) {
            if( form.elements[ i].type != "submit" && form.elements[ i].type != "reset") {
                buffer += "<element id='" + form.elements[i].name + "' type='" +
                                form.elements[ i].type + "'>" +
                                form.elements[ i].value + "</element>\n";
            }
        }
        buffer += "</form>\n";
        return buffer;
    },
    saveState : function( newURL) {
        var buffer = this.onSaveState()
        var request = new Asynchronous();
        var thisReference = this;
        var oldPath = location.pathname;
        request.openCallback = function( xmlhttp) {
            if( location.hash.length == 0) {
                xmlhttp.setRequestHeader( thisReference.constPageStateHeader, "none");
            }
            else {
                xmlhttp.setRequestHeader( thisReference.constPageStateHeader, location.hash.slice(1));
            }
        }
        var xmlhttp = request._xmlhttp;
        var tempNewURL = newURL;
        request.complete = function( status, statusText, responseText, responseXML) {
            if(status == 200) {
                var splitLocation = location.href.split( "#");
                location.replace( oldPath + "#" + xmlhttp.getResponseHeader( thisReference.constPageStateHeader));
                location.href = tempNewURL;
            }
        }
        request.username = this.username;
        request.password = this.password;
        var splitLocation = location.href.split( "#");
        request.post( splitLocation[ 0] + this.constURLStateIdentifier, this.constResourceStateContentType, buffer.length, buffer);
        return false;
    }
}


var StateNavigatorWindowName = {
    username: null,
    password: null,
    postURL: null,

    constPageStateHeader : "X-Page-State",
    constPageWindowName  : "X-Page-Window-Name",
    constPageOriginalURL : "X-Page-Original-URL",
    constPageWindowNamePrefix : "StateController",
    constResourceStateContentType : "application/xml",
    constURLStateIdentifier : "/state",
    
    constStateTag : "state",
    constHtmlPageStateTag : "html-page",

    verifyWindowName : function() {
        if( window.name.length == 0 ||
            window.name.indexOf( thisReference.constPageWindowNamePrefix) == -1) {
            window.name = GenerateUniqueIdentifer();
        }
    },
    
    onLoadState : function( status, responseXML) { },
    extractFormData : function( element, objData) {
        if( element.nodeType == 1) {
            if( element.nodeName == "form") {
                objData.formId = element.attributes.getNamedItem( "id").nodeValue;
                objData.formNode = document.forms[ objData.formId];
            }
            else if( element.nodeName == "element") {
                if( objData.formNode != null) {
                    var elementIdentifier = element.attributes.getNamedItem( "id").nodeValue;
                    if( element.childNodes[ 0] != null) {
                        var elementValue = element.childNodes[ 0].nodeValue;
                        objData.formNode.elements[ elementIdentifier].value = elementValue;
                    }
                }
            }
        }
    },
    loadForm : function( xmlState) {
        this.verify = this.extractFormData;
        var objData = new Object();
        XMLIterateElements( this, objData, xmlState);
    },
    extractUserData : function( element, objData) {
        if( element.nodeType == 1) {
            if( element.nodeName == this.constHtmlPageStateTag) {
                objData.foundElement = element;
            }
        }
    },
    loadState : function() {
        if( location.hash != null) {
            var asynch = new Asynchronous();
            var thisReference = this;
            asynch.openCallback = function( xmlhttp) {
                if( location.hash.length == 0) {
                    xmlhttp.setRequestHeader( thisReference.constPageStateHeader, "none");
                }
                else {