public KalkCurrency GetOrSetCurrency(string name = null, decimal?value = null)
{
if (name == null)
{
return(GetSafeBaseCurrencyFromConfig());
}
if (value == null)
{
return(RegisterBaseCurrency(name));
}
// Verify that the currency name is valid
KalkCurrency.CheckValid(Engine.CurrentSpan, name);
if (Engine.Units.TryGetValue(name, out var symbol))
{
if (symbol is KalkCurrency currency)
{
var baseCurrency = GetSafeBaseCurrencyFromConfig();
if (baseCurrency == currency)
{
throw new ScriptRuntimeException(Engine.CurrentSpan, $"Cannot change the rate of the base currency `{name}`.");
}
currency.Value = new KalkBinaryExpression(1.0m / value, ScriptBinaryOperator.Multiply, baseCurrency);
return(currency);
}
throw new ScriptRuntimeException(Engine.CurrentSpan, $"Unable to define currency `{name}` as it is already attached to a different unit: {symbol}.");
}
// New currency
return(RegisterCurrency(name, value.Value, true));
}
public KalkCurrency RegisterBaseCurrency(string name)
{
if (name == null)
{
throw new ArgumentNullException(nameof(name));
}
KalkCurrency.CheckValid(Engine.CurrentSpan, name);
KalkCurrency baseCurrency;
if (Engine.Units.TryGetValue(name, out var unit))
{
baseCurrency = unit as KalkCurrency;
if (baseCurrency != null)
{
// It is already the default unit
if (unit.Value == null)
{
return(baseCurrency);
}
var existingBase = GetSafeBaseCurrencyFromConfig();
var existingConvert = (KalkBinaryExpression)unit.Value;
unit.Value = null;
// ratio USD = 1.1 EUR
var ratio = Engine.ToObject <decimal>(Engine.CurrentSpan, existingConvert.Value);
existingBase.Value = new KalkBinaryExpression(1.0m, ScriptBinaryOperator.Multiply, baseCurrency);
foreach (var currency in Engine.Units.Values.OfType <KalkCurrency>())
{
if (currency == baseCurrency)
{
continue;
}
var existingRatio = Engine.ToObject <decimal>(Engine.CurrentSpan, ((KalkBinaryExpression)currency.Value).Value);
currency.Value = new KalkBinaryExpression(existingRatio / ratio, ScriptBinaryOperator.Multiply, baseCurrency);
}
}
else
{
throw new ArgumentException($"Cannot create a new base currency for the existing unity `{unit}`.", nameof(name));
}
}
else
{
if (Currencies.Count > 0)
{
throw new ArgumentException($"Cannot create a new base currency when there are already currencies. You need to first create this currency relative to the existing base `{GetSafeBaseCurrencyFromConfig().Name}` currency", nameof(name));
}
baseCurrency = new KalkCurrency(this, name)
{
Description = "Default Currency"
};
Engine.Units.Add(name, baseCurrency);
}
BaseCurrency = name;
return(baseCurrency);
}
