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

 * JavaScript functions supporting AJAX access to category and 

 * location tables and the building of the <select> dropdown lists

 */

var useAJAX = true;

var xmlOptions;

var spanIds = {"country":"Country", "state":"State", "city":"City"};

var adminPath = ""; // this is necessary for processing admin_add_img_frm



/**

 * When the category changes this function issues an XMLHttpRequest to cat2Handler.php

 * which returns the HTML <select>...</select> for the appropriate subcategory. The

 * responseText is simply assigned to the innerHTML of a <span id="subcat"> on the page.

 */

function categoryChange(){

	var category = document.getElementById('category');

	var index = category.selectedIndex;

	var data = category.options[index].value;

	var callback = {

		success: function(respText, respXML){

			var obj = document.getElementById('subcat');

			obj.innerHTML = respText;

		},

		failure: function(status){ alert("Ajax Failure: " + status);}

	};

	

	var myhandler = new SimpleHandler();

	myhandler.requestUrlEncoding('POST', adminPath + 'cat2Handler.php', callback, 'category=' + data);

}



/**

 * When there is a location change this function constructs the appropriate

 * URL for an XMLHttpRequest which will return the XML for an array of <options>

 * for the <select> that is dependent on changes in the 'loc' parameter.

 * 

 * @param loc	a string identifying the 'id' of the location <select> element

 *			that has changed.

 */

function locationChange(loc){

	var domain = 'http://localhost/zummin/';

	var source = 'regionHandler.php';

	var id = "";

	var rcode = "";	// region code, from region selection

	var ccode = ""; // country code, from country selection

	var scode = ""; // state code, from state selection

	var data;

	var index; 

	var query;

	var selObj;

	

	// get the id ('country', 'state' or 'city') and the code (selection value)

	// also build each selection's query string

	switch(loc){

		case 'region':

			source = 'countryHandler.php';

			id = "country";

			

			// build the query string for the region

			selObj = document.getElementById(loc);

			index = selObj.selectedIndex;

			rcode = selObj.options[index].value;

			query = loc + "=" + rcode;

			break;

		case 'country':

			source = 'stateHandler.php';

			id = "state";

			

			// 1st get the region's code (from the previous selection)

			selObj = document.getElementById('region');

			index = selObj.selectedIndex;

			rcode = selObj.options[index].value;

			

			// now build the query string for the country (the current selection)

			selObj = document.getElementById(loc);

			index = selObj.selectedIndex;

			data = selObj.options[index].value;

			query = 'region=' + rcode + "&" + loc + "=" + data;

			break;

		case 'state':

			source = 'cityHandler.php';

			id = 'city';

			

			// get the country code from the country selection

			selObj = document.getElementById('country');

			index = selObj.selectedIndex;

			ccode = selObj.options[index].value;

			

			// now get the current location selection and build its query string

			selObj = document.getElementById(loc);

			index = selObj.selectedIndex;

			data = selObj.options[index].value;

			query = 'country=' + ccode + "&" + loc + "=" + data;

			break;

		default:

			break;

	}



	var callback = {

		success: function(respText, respXML){

			var obj = document.getElementById('useAjax' + spanIds[id]);

			obj.innerHTML = respText;

		},

		failure: function(status){ alert("Ajax Failure: " + status);}

	};

	

	var myhandler = new SimpleHandler();

	myhandler.requestUrlEncoding('POST', adminPath + source, callback, query);

}



/**

 * This function will build the option list for the location <select> element whose

 * id matches.

 *

 * @param id	a string containing the 'id' attribute of <select> element

 * @param obj	a json object containing pairs; where key (or prop) is value in <Option value="prop">obj[prop]</Option>

 */

function buildSelect(id, obj){

	var selectControl = document.getElementById(id);

	clearSelect(selectControl);



	for (var prop in obj){

		var newOption = document.createElement('option');

		newOption.setAttribute('value', prop);

		newOption.appendChild(document.createTextNode(obj[prop]));

		

		selectControl.appendChild(newOption);

	}

}







function clearSelect(selControl){

	if (selControl){	

		// remove all options except the first one (which should be '-- Select --')

		for (var i = 1; i < selectControl.options.length; i++){

			selectControl.removeChild(selectControl.options[i]);

		}

	}

}



function voteYes(id){

	var callback = {

		success: function(respText, respXML){

			alert(respText);

		},

		failure: function(status){ alert("Ajax Failure: " + status);}

	};

	

	var myhandler = new SimpleHandler();

	myhandler.requestUrlEncoding('POST', adminPath + 'voteYesOnReview.php', callback, 'id=' + id);

}



function voteNo(id){

	var callback = {

		success: function(respText, respXML){

			alert(respText);

		},

		failure: function(status){ alert("Ajax Failure: " + status);}

	};

	

	var myhandler = new SimpleHandler();

	myhandler.requestUrlEncoding('POST', adminPath + 'voteNoOnReview.php', callback, 'id=' + id);

}