/*

Copyright (c) 2009, Yahoo! Inc. All rights reserved.

Code licensed under the BSD License:

http://developer.yahoo.net/yui/license.txt

version: 3.0.0

build: 1549

*/

YUI.add('io-form', function(Y) {

   /**

    * Extends the IO base class to enable HTML form data serialization, when specified

    * in the transaction's configuration object.

    * @module io

    * @submodule io-form

    */

    Y.mix(Y.io, {

       /**

        * @description Method to enumerate through an HTML form's elements collection

        * and return a string comprised of key-value pairs.

        *

        * @method _serialize

        * @private

        * @static

        * @param {object} c - YUI form node or HTML form id.

        * @param {string} s - Transaction data defined in the configuration.

        * @return string

        */

        _serialize: function(c, s) {

			var eUC = encodeURIComponent,

            	data = [],

            	useDf = c.useDisabled || false,

            	item = 0,

            	id = (typeof c.id === 'string') ? c.id : c.id.getAttribute('id'),

            	e, f, n, v, d, i, il, j, jl, o;

            	if (!id) {

					id = Y.guid('io:');

					c.id.setAttribute('id', id);

				}

            	f = Y.config.doc.getElementById(id);

            // Iterate over the form elements collection to construct the

            // label-value pairs.

            for (i = 0, il = f.elements.length; i < il; ++i) {

                e = f.elements[i];

                d = e.disabled;

                n = e.name;

                if ((useDf) ? n : (n && !d)) {

                    n = encodeURIComponent(n) + '=';

                    v = encodeURIComponent(e.value);

                    switch (e.type) {

                        // Safari, Opera, FF all default options.value from .text if

                        // value attribute not specified in markup

                        case 'select-one':

                            if (e.selectedIndex > -1) {

                                o = e.options[e.selectedIndex];

                                data[item++] = n + eUC((o.attributes.value && o.attributes.value.specified) ? o.value : o.text);

                            }

                            break;

                        case 'select-multiple':

                            if (e.selectedIndex > -1) {

                                for (j = e.selectedIndex, jl = e.options.length; j < jl; ++j) {

                                    o = e.options[j];

                                    if (o.selected) {

                                      data[item++] = n + eUC((o.attributes.value && o.attributes.value.specified) ? o.value : o.text);

                                    }

                                }

                            }

                            break;

                        case 'radio':

                        case 'checkbox':

                            if(e.checked){

                                data[item++] = n + v;

                            }

                            break;

                        case 'file':

                            // stub case as XMLHttpRequest will only send the file path as a string.

                        case undefined:

                            // stub case for fieldset element which returns undefined.

                        case 'reset':

                            // stub case for input type reset button.

                        case 'button':

                            // stub case for input type button elements.

                            break;

                        case 'submit':

                        default:

                            data[item++] = n + v;

                    }

                }

            }

            return s ? data.join('&') + "&" + s : data.join('&');

        }

    }, true);

}, '3.0.0' ,{requires:['io-base','node-base','node-style']});