var Result=0, Operator=0, Second=0, Ready=0, Done=1, Complete=0, Integer, CurrentValue;

function reset(value)
{
	document.calculator.LED.value = value;
	Result = 0, Operator = 0, Second = 0, Ready = 0; Done = 1; Complete = 0;
}
function SetValue(NewValue)
{
	Integer = 1;
	if(Second || Done)
	{
		Second = 0;
		Done = 0;
		CurrentValue = NewValue;
	}
	for(var i=0; i<CurrentValue.length; i++)
		if (CurrentValue[i]=='.')
			Integer=0;
}
function Click(Caption)
{
	CurrentValue = document.calculator.LED.value;
	if(Caption=='.')
	{
		SetValue('0');
		if(Integer)
		{
			CurrentValue += Caption;
			document.calculator.LED.value = CurrentValue;
			Complete = 0;
		}
	}
	if (Caption.length == 1 && Caption>='0' && Caption<='9')
	{
		SetValue('');
		if(CurrentValue=='0')
			CurrentValue='';
		CurrentValue += Caption;
		document.calculator.LED.value = CurrentValue;
		Complete = 1;
	}
	if (Caption=='pi')
	{
		CurrentValue = Math.PI;
		document.calculator.LED.value = CurrentValue;
		Complete = 1;
	}
	if (Caption=='e')
	{
		CurrentValue = Math.E;
		document.calculator.LED.value = CurrentValue;
		Complete = 1;
	}
	if(Caption=='-' || Caption=='+' || Caption=='/' || Caption=='*' || Caption=='^')
	{
		if(Second)
			Operator = Caption
		else
		{
			if(!Ready)
			{
				Operator = Caption;
				Result = CurrentValue;
				Ready=1;
			} else
			{
				if (Operator=='^')
					Result = Math.pow(Result, CurrentValue);
				else
					Result = eval(Result + Operator + CurrentValue);
				Operator = Caption; document.calculator.LED.value = Result;
			} Complete=0; Second = 1;
		}
	}
	if(Caption=='1/x' )
	{
		Result = eval('1/' + CurrentValue) ; reset(Result);
	}
	if(Caption=='sqrt')
	{
		Result = Math.sqrt(CurrentValue);
		reset(Result);
	}
	if(Caption=='exp' )
	{
		Result = Math.exp(CurrentValue);
		reset(Result);
	}
	if(Caption=='log' )
	{
		Result = Math.log(CurrentValue) / Math.LN10;
		reset(Result);
	}
	if(Caption=='ln' )
	{
		Result = Math.log(CurrentValue);
		reset(Result);
	}
	if(Caption=='sin' )
	{
		Result = CurrentValue;
		if (document.calculator.angle[0].checked)
			Result = Result * Math.PI / 180;
		if (document.calculator.angle[2].checked)
			Result = Result * Math.PI / 200;
		Result = Math.sin(Result);
		reset(Result);
	}
	if(Caption=='cos' )
	{
		Result = CurrentValue;
		if (document.calculator.angle[0].checked)
			Result = Result * Math.PI / 180;
		if (document.calculator.angle[2].checked)
			Result = Result * Math.PI / 200;
		Result = Math.cos(Result);
		reset(Result);
	}
	if(Caption=='tan' )
	{
		Result = CurrentValue;
		if (document.calculator.angle[0].checked)
			Result = Result * Math.PI / 180;
		if (document.calculator.angle[2].checked)
			Result = Result * Math.PI / 200;
		Result = Math.tan(Result);
		reset(Result);
	}
	if(Caption=='asin' )
	{
		Result = Math.asin(CurrentValue);
		if (document.calculator.angle[0].checked)
			Result = Result * 180 / Math.PI;
		if (document.calculator.angle[2].checked)
			Result = Result * 200 / Math.PI;
		reset(Result);
	}
	if(Caption=='acos' )
	{
		Result = Math.acos(CurrentValue);
		if (document.calculator.angle[0].checked)
			Result = Result * 180 / Math.PI;
		if (document.calculator.angle[2].checked)
			Result = Result * 200 / Math.PI;
		reset(Result);
	}
	if(Caption=='atan' )
	{
		Result = Math.atan(CurrentValue);
		if (document.calculator.angle[0].checked)
			Result = Result * 180 / Math.PI;
		if (document.calculator.angle[2].checked)
			Result = Result * 200 / Math.PI;
		reset(Result);
	}
	if(Caption=='sinh' )
	{
		Result = Math.exp(CurrentValue);
		Result = (Result - 1 / Result) / 2;
		reset(Result);
	}
	if(Caption=='cosh' )
	{
		Result = Math.exp(CurrentValue);
		Result = (Result + 1 / Result) / 2;
		reset(Result);
	}
	if(Caption=='tanh' )
	{
		Result = Math.exp(CurrentValue);
		Result = (Result - 1 / Result) / (Result + 1 / Result);
		reset(Result);
	}
	if(Caption=='asinh' )
	{
	//sign(x) * log(|x| + sqrt(x*x+1))
	//	alert(CurrentValue + Math.sqrt(CurrentValue * CurrentValue + 1));
	//	Result = Math.log(CurrentValue + Math.sqrt(CurrentValue * CurrentValue + 1));
		Result = CurrentValue / Math.abs(CurrentValue) * Math.log(Math.abs(CurrentValue) + Math.sqrt(CurrentValue * CurrentValue + 1));
		reset(Result);
	}
	if(Caption=='acosh' )
	{
	//2 log  (sqrt((x+1)/2) + sqrt((x-1)/2)) 
		Result = 2 * Math.log(Math.sqrt((CurrentValue + 1) / 2) + Math.sqrt((CurrentValue - 1) / 2));
		reset(Result);
	}
	if(Caption=='atanh' )
	{
	//0.5*log((x-1)/(x+1))
		Result = Math.log((CurrentValue - 1) / (CurrentValue + 1)) / 2;
		reset(Result);
	}
	if(Caption=='+/-')
		document.calculator.LED.value = eval(-CurrentValue);
	if(Caption=='=' && Complete && Operator!='0')
	{
		if (Operator=='^')
		{
			Result = Math.pow(Result, CurrentValue);
			reset(Result);
		} else
			reset(eval(Result + Operator + CurrentValue));
	}
	if (Caption=='C')
		reset(0);
	if(document.calculator.LED.value[0] == '.')
		document.calculator.LED.value = '0' + document.calculator.LED.value;
}