// JavaScript Document


function stripCommas(numString) {
    var re = /,/g;
    return numString.replace(re,"");
}

function calc(from)
{
	total_miles = 0;
	current_cost = 0;
	fuel_cost_before = 0;
	new_total_miles = 0;
	new_cost = 0;
	fuel_cost_after = 0;
	total_savings = 0;
	f = document.calculate1;
	mpg = stripCommas(f.mpg.value);
	projected_mpg = stripCommas(f.projected_mpg.value);
	cap = stripCommas(f.capacity.value);
	cost = stripCommas(f.cost.value);
	miles = stripCommas(f.miles_driven.value);
	if (from=='miles_cost')
	{
				total_miles = mpg * cap;
				if (total_miles.toFixed) //if browser supports toFixed() method
				f.total_miles.value = total_miles.toFixed(0);
				
				current_cost = (cost * cap) / (mpg * cap);
				if (current_cost.toFixed) //if browser supports toFixed() method
				f.current_cost.value = current_cost.toFixed(2);
				
				fuel_cost_before = miles * current_cost.toFixed(2);
				if (fuel_cost_before.toFixed) //if browser supports toFixed() method
				f.fuel_cost_before.value = fuel_cost_before.toFixed(2);
				
				new_total_miles = projected_mpg * cap;
				if (total_miles.toFixed) //if browser supports toFixed() method
				f.new_total_miles.value = new_total_miles.toFixed(0);
				
				new_cost = (cost * cap) / (projected_mpg * cap);
				if (new_cost.toFixed) //if browser supports toFixed() method
				f.new_cost.value = new_cost.toFixed(2);
				
				fuel_cost_after = miles * new_cost.toFixed(2);
				if (fuel_cost_after.toFixed) //if browser supports toFixed() method
				f.fuel_cost_after.value = fuel_cost_after.toFixed(2);
				
				total_savings = fuel_cost_before - fuel_cost_after;
				if (total_savings.toFixed) //if browser supports toFixed() method
				f.total_savings.value = total_savings.toFixed(2);
	}
}