// globals
var g_sMenuItem = "";

// image cache controls
var g_objImageCache = new Object();
var g_iImageIndex = 0;
CacheImage("http://static.wai-thai.com/images/logo.gif");

CacheImage("http://static.wai-thai.com/images/menu_home_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_about_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_food_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_worldwide_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_contact_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_home_on.gif");
CacheImage("http://static.wai-thai.com/images/menu_about_on.gif");
CacheImage("http://static.wai-thai.com/images/menu_food_on.gif");
CacheImage("http://static.wai-thai.com/images/menu_worldwide_on.gif");
CacheImage("http://static.wai-thai.com/images/menu_contact_on.gif");

CacheImage("http://static.wai-thai.com/images/menu_starters_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_rice_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_soup_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_locations_off.gif");
CacheImage("http://static.wai-thai.com/images/menu_starters_on.gif");
CacheImage("http://static.wai-thai.com/images/menu_rice_on.gif");
CacheImage("http://static.wai-thai.com/images/menu_soup_on.gif");
CacheImage("http://static.wai-thai.com/images/menu_locations_on.gif");

CacheImage("http://static.wai-thai.com/images/submit_on.gif");

String.prototype.trim = function() {
	return(this.replace(/^\s+/,'').replace(/\s+$/,''));
}

function CacheImage(sFilename) {
	g_objImageCache[g_iImageIndex] = new Image();
	g_objImageCache[g_iImageIndex].src = sFilename;
	g_iImageIndex++;
}

function MenuHover(objMenu, bHover) {
	if (objMenu.id != g_sMenuItem) {
		if (bHover == true) {
			objMenu.src = ("http://static.wai-thai.com/images/" + objMenu.id + "_on.gif");
		} else {
			objMenu.src = ("http://static.wai-thai.com/images/" + objMenu.id + "_off.gif");
		}
	}
}

function SetMenuItem(sItem) {
	MenuHover(document.getElementById("menu_" + sItem), true);
	g_sMenuItem = ("menu_" + sItem);

	switch (sItem) {
	  case "starters":
	    CacheImage("http://static.wai-thai.com/images/dish_chickenlemongrass_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_springrolls_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_chickensatay_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_beefsalad_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_stirfriedveg_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_spicyvegsalad_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_spicyfruitsalad_on.gif");
	    break;
	  case "rice":
	    CacheImage("http://static.wai-thai.com/images/dish_vegfriedrice_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_chickenfriedrice_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_porkfriedrice_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_prawnfriedrice_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_padkrapao_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_tofugreencurry_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_chickgreencurry_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_tofupenang_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_chickpenang_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_prawnpenang_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_massaman_on.gif");
	    break;
	  case "soup":
	    CacheImage("http://static.wai-thai.com/images/dish_chickentomkha_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_mushroomtomkha_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_shrimptomyam_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_mushroomtomyam_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_chickensoupnoodle_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_spareribs_on.gif");
	    CacheImage("http://static.wai-thai.com/images/dish_padthai_on.gif");
	    break;
	}
}

function ValidChar(sSingle, sChars) {
	bValid = false;
	for (var iIndex = 0; iIndex < sChars.length; iIndex++) {
		if (sSingle == sChars.charAt(iIndex)) {
			return true;
		}
	}
	return false;
}

function ValidateEmail(sString) {
	// trim leading and trailing spaces
	sString = sString.trim();

	// check for spaces
	sString = sString.toLowerCase();
	for (var iIndex = 0; iIndex < sString.length; iIndex++) {
		bCharValid = ValidChar(sString.charAt(iIndex),
													 "abcdefghijklmnopqrstuvwxyz0123456789@-_.");
		if (bCharValid != true) {
			return false;
		}
	}

	// check for single '@' sign
	arrEmail = sString.split("@");
	if (arrEmail.length != 2) {
		return false;
	}

	// check before '@' sign
	if (arrEmail[0].length < 1) {
		return false;
	}

	// check after '@' sign
	arrDomain = arrEmail[1].split(".");
	if (arrDomain.length < 2) {
		return false;
	}
	for (var iIndex = 0; iIndex < arrDomain.length; iIndex++) {
		if ((arrDomain[iIndex].length < 1) || (arrDomain[iIndex].length > 64)) {
			return false;
		}
	}

	// email is valid
	return true;
}

function ValidateForm(objForm) {
	// validate name
	sName 		= objForm.name.value;
	sName.trim();
	if (sName.length < 1) {
		alert("You did not enter your name. Please try again.");
		return false;
	}

	// validate email
	if (ValidateEmail(objForm.email.value) != true) {
		alert("The email address you entered was invalid. Please try again.");
		return false;
	}
}