// This file provides miscellaneous functionality and up-to-date numbers for givingwhatwecan.org javascripts

// This takes a three letter currency code and returns the number of US$ that one unit of that currency can buy

function getCurrencyFactor(currency)
{
	var currencyFactor;

	// Set up exchange rates (correct as of 2007-04-23)
	usd = 1.0000;
	aud = 0.9142;
	cad = 0.9344;
	eur = 1.4818;
	gbp = 1.6558;
	jpy = 0.0109;
    
	if (currency == "aud")
	{
		currencyFactor = aud;
	}
	else if (currency == "cad")
	{
		currencyFactor = cad;
	}
	else if (currency == "eur")
	{
		currencyFactor = eur;
	}
	else if (currency == "gbp")
	{
		currencyFactor = gbp;
	}
	else if (currency == "jpy")
	{
		currencyFactor = jpy;
	}
	else if (currency == "usd")
	{
		currencyFactor = usd;
	}

	return currencyFactor;
}

// This returns the current number of US dollars needed to save a life
// Using the mid point for the range for DOTS treatment

function pricePerLifeSaved()
{
	return 450;
}


// This returns the current number of US dollars needed to save a DALY

function pricePerDALY()
{
	return 3;
}


// This returns the current number of US dollars needed to gain a year of school attendance

function pricePerSchoolYear()
{
	return 3;
}


function filterChars(s, charList)
{
	var s1 = "" + s; // force s1 to be a string data type
	var i;
	for (i = 0; i < s1.length; )
	{
		if (charList.indexOf(s1.charAt(i)) < 0)
			s1 = s1.substring(0,i) + s1.substring(i+1, s1.length);
		else
			i++;
	}
	return s1;
}

function makeNumeric(s)
{
	return filterChars(s, "1234567890.-");
}

function numval(val,digits,minval,maxval)
{
	val = makeNumeric(val);
	if (val == "" || isNaN(val)) val = 0;
	val = parseFloat(val);
	if (digits != null)
	{
		var dec = Math.pow(10,digits);
		val = (Math.round(val * dec))/dec;
	}
	if (minval != null && val < minval) val = minval;
	if (maxval != null && val > maxval) val = maxval;
	return parseFloat(val);
}

function formatNumber(val,digits,minval,maxval)
{
	var sval = "" + numval(val,digits,minval,maxval);
	var i;
	var iDecpt = sval.indexOf(".");
	if (iDecpt < 0) iDecpt = sval.length;
	if (digits != null && digits > 0)
	{
		if (iDecpt == sval.length)
			sval = sval + ".";
		var places = sval.length - sval.indexOf(".") - 1;
		for (i = 0; i < digits - places; i++)
			sval = sval + "0";
	}
	var firstNumchar = 0;
	if (sval.charAt(0) == "-") firstNumchar = 1;
	for (i = iDecpt - 3; i > firstNumchar; i-= 3)
		sval = sval.substring(0, i) + "," + sval.substring(i);

	return sval;
}

//function formatCurrency(currencySymbol,val,digits,minval,maxval)
//{
//	return currencySymbol + formatNumber(val,digits,minval,maxval);
//}


function clearText(thefield){
	if (thefield.defaultValue==thefield.value)
	{
		thefield.value = "";
		thefield.style.color = "#000";
	}
}