function calculate_metal_value(metal, weight, update_field)
{
	$.getJSON("/sell-to-us/buy-back-value/" + metal + "/" + weight + "/", function(data) {
		update_field.val(data.value)
	});
}

function calculate_coin_value(coin_id, quantity, update_field)
{
	$.getJSON("/sell-to-us/buy-back-value/coins/" + coin_id + "/" + quantity + "/", function(data) {
		update_field.val(data.value.toFixed(2))
	});
}

function set_gold_value()
{
    weight = parseFloat($("#id-calc-gold-weight").val());
    if (!isNaN(weight))
    {
    	calculate_metal_value("gold-bars", weight, $("#id-calc-gold-value"));
    }

    // Stop link from being followed.
    return false;
}

function set_silver_value()
{
    weight = parseFloat($("#id-calc-silver-weight").val());
    if (!isNaN(weight))
    {
    	calculate_metal_value("silver-bars", weight, $("#id-calc-silver-value"));
    }

    // Stop link from being followed.
    return false;
}

function set_gold_coin_value()
{
	coin_id = $("#id-calc-gold-coin").val();
	quantity = parseFloat($("#id-calc-gold-coin-qty").val());
	if (coin_id != "" && !isNaN(quantity))
	{
		calculate_coin_value(coin_id, quantity, $("#id-calc-gold-coin-value"));
	}

    // Stop link from being followed.
    return false;
}

function set_silver_coin_value()
{
	coin_id = $("#id-calc-silver-coin").val();
	quantity = parseFloat($("#id-calc-silver-coin-qty").val());
	if (coin_id != "" && !isNaN(quantity))
	{
		calculate_coin_value(coin_id, quantity, $("#id-calc-silver-coin-value"));
	}

    // Stop link from being followed.
    return false;
}