/* Copyright: Martin J. Marsh, March 2007 - www.ecomarshosgame.com - Individual use permissions only. Version 1.2 */ 

var entrval, calculol=0, chckval="", optalli=0, restalli=0;

function displtrig(displval){
entrval = document.form1.displ.value;
entrval = entrval + displval;
document.form1.displ.value = entrval;
var currval = document.form1.displ.value;
document.form1.initval.value = currval;
}

function displtrg2(){
entrval = document.form1.displ.value;
entrval = entrval + ".";
document.form1.displ.value = entrval;
var currval = document.form1.displ.value;
document.form1.initval.value = currval; // 20
}

function protecval(){
document.form1.displ.value="ERROR";
setTimeout('clearall()', 1000);}

function opsopts(opnumber){
var sofarsg = toString(document.form1.resval.value);
optalli = document.form1.thoptall.value;
optalli++;
document.form1.thoptall.value = optalli;
if (optalli > 1){
clearall();
document.form1.displ.value = "One sum at once ";
return;
}
var ophold = document.form1.initval.value;
if ((ophold == chckval) && (opnumber == 3))
{document.form1.displ.value = "CALCULATOR"; setTimeout('clearall()', 1000); return;}
if ((ophold == chckval) && (opnumber == 4))
{document.form1.displ.value = "CALCULATOR"; setTimeout('clearall()', 1000); return;}
document.form1.resval.value = document.form1.initval.value;
switch (opnumber) {
case 1:
ophold = "+";
break;
case 2:
ophold = "-";
break;
case 3:
ophold = "*"; //50
break;
case 4:
ophold = "/";
break;
default:
return false;
}
if(document.form1.opval.value == "")
{document.form1.opval.value = ophold}
else
{document.form1.resval.value += ophold}
document.form1.displ.value = "";
}

function resultGiv(){
restalli++;
if (restalli > 1){
clearall();
document.form1.displ.value = "One sum at once ";
return;
} 
document.form1.thoptall.value = "0";
if (nuoperand == ""){
clearall(); document.form1.displ.value = " ERROR ";
return;
}
if (nuoperand == " ERROR "){
clearall();
document.form1.displ.value = " ERROR ";
return;
}
var nuoperand = document.form1.displ.value;
var opholdyet = eval(document.form1.resval.value);
opholdyet = opholdyet + document.form1.opval.value;
opholdyet = opholdyet + nuoperand;
var resultz = opholdyet;
calculol = eval(resultz);
calculol = 1000*calculol; 
calculol = parseInt(calculol)/10;
calculol = parseInt(calculol)/100;
document.form1.displ.value = calculol;
document.form1.resval.value = calculol;
}

function clearentr()
{
document.form1.displ.value = "";
}

function clearall()
{
document.form1.displ.value = "";
document.form1.initval.value = "";
document.form1.opval.value = "";
document.form1.resval.value = "";
document.form1.thoptall.value = "0";
}

/* For next improvement... sofarsg = eval(document.form1.resval.value);
document.form1.resval.value = sofarsg */