/// <summary>
/// Converts BigInteger to the minimal possible number type
/// Negative numbers get converted to positive numbers prefixed with '-'
/// For example, -520582(BigInteger) -> '-'(char) 52082(int)
/// </summary>
object[] ConvertBigIntegerToRefalNumber(BigInteger bigIntValue)
{
var negative = bigIntValue < 0;
var result = new object[negative ? 2 : 1];
var valueIndex = negative ? 1 : 0;
if (negative)
{
result[0] = '-';
bigIntValue = -bigIntValue;
}
int intValue;
long longValue;
if (bigIntValue.AsInt32(out intValue))
{
result[valueIndex] = intValue;
}
else if (bigIntValue.AsInt64(out longValue))
{
result[valueIndex] = longValue;
}
else
{
result[valueIndex] = bigIntValue;
}
return(result);
}
// extract arguments and convert to BigIntegers
void GetBigIntegerArguments(PassiveExpression expr, out BigInteger arg1, out BigInteger arg2)
{
object op1, op2;
GetArguments(expr, out op1, out op2);
arg1 = ToBigInteger(op1);
arg2 = ToBigInteger(op2);;
}
// find the first numeric symbol in an expression and convert to BigInteger
BigInteger ToBigInteger(object value)
{
// try convert expression
var expr = value as PassiveExpression;
if (expr != null)
{
int sign = 1;
foreach (object o in expr)
{
if (o is StructureBrace)
{
continue;
}
if (o is char)
{
var c = (char)o;
if (c == '-')
{
sign *= -1;
}
}
if (o is int)
{
return(BigInteger.Create(sign * (int)o));
}
if (o is long)
{
return(BigInteger.Create(sign * (long)o));
}
if (o is BigInteger)
{
return(sign * (BigInteger)o);
}
// warning: BigInteger doesn't support parsing strings
if (o is string)
{
return(BigInteger.Create(sign * Convert.ToInt64(o)));
}
}
return(BigInteger.Zero);
}
// try convert single symbol
if (value is int)
{
return(BigInteger.Create((int)value));
}
if (value is long)
{
return(BigInteger.Create((long)value));
}
if (value is BigInteger)
{
return((BigInteger)value);
}
if (value is string)
{
return(BigInteger.Create(Convert.ToInt64(value)));
}
return(BigInteger.Zero);
}
