var letters="bcdfghjkmnpqrstvwxyz23456789";	
var letimg= new Array();
var letter_string;
var random_num=6;

function get_random()
{
    var ranNum= Math.floor(Math.random()*letters.length);
    return ranNum;
}

//get 6 random letters
function get_letters(){
	var num, one_letter;
	var i;
	
	letter_string="";
	for(i=0; i<random_num; i++){
		num = get_random();
		one_letter = letters.charAt(num);
		letter_string+=one_letter;
		letimg[i]= one_letter+".gif";
	}
	
	//alert(letter_string +" first image will be "+letimg[0]);
}


function drop_image(){
	var i;
	get_letters();
//	for(i=0; i<random_num; i++){
//		document.write("<image src=/mxp-theme/images/letters/" + letimg[i] + ">");
//	}
	document.write("<big>" + letter_string + "</big>");		//use print letter, not image simplicity
}


function isMatch(myForm){
//alert("isMatch called");

	var i;
//	var keyin_value= myText.value.toLowerCase();
	var keyin_value = myForm.letters.value.toLowerCase();
	var matchit=true;

	if(keyin_value=="" || keyin_value==null || keyin_value==undefined){
		alert("Please enter matching letters before submit.");
		matchit=false;
	}
	
	else for(i=0; i<keyin_value.length; i++){
		if(keyin_value.charAt(i)!= letter_string.charAt(i)){ 
			//alert("first=" + keyin_value.charAt(i) + " second="+letter_string.charAt(i));
			matchit=false;
			alert("Letters are not match, please try again. ");
			//myText.value="";
			break;
		}
	}
	if(matchit==true) {
		myForm.submit();
	}
//	alert("match: " +matchit);
	//return matchit;
}