/// <summary>
/// Selects a random number between 0 and an upper-bound
/// </summary>
/// <param name="provider">Random Number Generator to use</param>
/// <param name="upperBound">The upper-bound (exclusive) of random number selection</param>
/// <returns>A random number between 0 (inclusive) and the given upper-bound (exclusive)</returns>
public static int RandomNumber(this IPRNGFortunaProvider provider, int upperBound)
{
int numBits = PowUpperBound(upperBound);
var numBytes = (int)Math.Ceiling(numBits / 8d);
var offset = numBits % 8;
int retVal;
var bytes = new byte[numBytes];
do
{
provider.GetBytes(bytes);
// Now we need to conditionally dispose of any extra bits
if (offset != 0)
{
var bits = new BitArray(bytes);
// Truncate (zero-out) high-order bits, if necessary
if (BitConverter.IsLittleEndian)
{
for (var i = bits.Length - 1; i > numBits; i--)
{
bits.Set(i, false);
}
}
else
{
for (var i = 0; i < bits.Length - numBits; i++)
{
bits.Set(i, false);
}
}
var truncatedBytes = new byte[numBytes];
((ICollection)bits).CopyTo(truncatedBytes, 0);
bytes = truncatedBytes;
}
var prepostFix = Enumerable.Repeat((byte)0, sizeof(int) - bytes.Length);
var intBytes = BitConverter.IsLittleEndian
? bytes.Concat(prepostFix)
: prepostFix.Concat(bytes);
retVal = BitConverter.ToInt32(intBytes.ToArray(), 0);
} while (retVal != 0 && retVal >= upperBound);
return(Math.Abs(retVal));
}
/// <summary>
/// Selects a random number between 0 and an upper-bound
/// </summary>
/// <param name="provider">Random Number Generator to use</param>
/// <param name="upperBound">The upper-bound (exclusive) of random number selection</param>
/// <returns>A random number between 0 (inclusive) and the given upper-bound (exclusive)</returns>
public static int RandomNumber(this IPRNGFortunaProvider provider, int upperBound)
{
int numBits = PowUpperBound(upperBound);
var numBytes = (int)Math.Ceiling(numBits / 8d);
//var offset = numBits % 8;
var offset = 8 - numBits % (numBytes * 8);
int retVal;
var bytes = new byte[numBytes];
do
{
provider.GetBytes(bytes);
// Now we need to conditionally dispose of any extra bits
if (offset != 0)
{
if (BitConverter.IsLittleEndian)
{
bytes[bytes.Length - 1] = (byte)(bytes[bytes.Length - 1] << offset);
bytes[bytes.Length - 1] = (byte)(bytes[bytes.Length - 1] >> offset);
}
else
{
bytes[0] = (byte)(bytes[0] >> offset);
bytes[0] = (byte)(bytes[0] << offset);
}
}
var prepostFix = Enumerable.Repeat((byte)0, 4 - bytes.Length);
var intBytes = BitConverter.IsLittleEndian
? bytes.Concat(prepostFix)
: prepostFix.Concat(bytes);
retVal = BitConverter.ToInt32(intBytes.ToArray(), 0);
} while (retVal != 0 && retVal >= upperBound);
return(Math.Abs(retVal));
}
public GamblingModule(GambleConfigFacade configFacade, GambleFacade gambleFacade, IPRNGFortunaProvider provider)
{
mConfigFacade = configFacade;
mGambleFacade = gambleFacade;
mProvider = provider;
}
