// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the Apache 2.0 License.
// See the LICENSE file in the project root for more information.
using System;
using System.Linq;
using System.Numerics;
using IronPython.Runtime;
using IronPython.Runtime.Operations;
using Microsoft.Scripting.Utils;
[assembly: PythonModule("_random", typeof(IronPython.Modules.PythonRandom))]
namespace IronPython.Modules {
public static partial class PythonRandom {
public const string __doc__ = "implements a random number generator";
[PythonType]
public class Random {
private RandomGen _rnd;
public Random(object seed = null) {
this.seed(seed);
}
#region Public API surface
public object getrandbits(int bits) {
if (bits <= 0) {
throw PythonOps.ValueError("number of bits must be greater than zero");
}
lock (this) {
return MathUtils.GetRandBits(_rnd.NextBytes, bits);
}
}
public PythonTuple getstate() {
object[] state;
lock (this) {
state = _rnd.GetState();
}
return PythonTuple.MakeTuple(state);
}
public object random() {
lock (this) {
byte[] randA = new byte[sizeof(uint)];
byte[] randB = new byte[sizeof(uint)];
_rnd.NextBytes(randA);
_rnd.NextBytes(randB);
// this is pulled from _randommodule.c from CPython
uint a = BitConverter.ToUInt32(randA, 0) >> 5;
uint b = BitConverter.ToUInt32(randB, 0) >> 6;
return (a * 67108864.0 + b) * (1.0 / 9007199254740992.0);
}
}
public void seed(object s = null) {
int newSeed;
switch (s) {
case null:
newSeed = DateTime.Now.GetHashCode();
break;
case int i:
newSeed = i;
break;
default:
if (!PythonContext.IsHashable(s)) {
throw PythonOps.TypeError("unhashable type: '{0}'", PythonOps.GetPythonTypeName(s));
}
newSeed = s.GetHashCode();
break;
}
lock (this) {
_rnd = new RandomGen(newSeed);
}
}
public void setstate(PythonTuple state) {
if (state.Count != 58) throw PythonOps.ValueError("state vector is the wrong size");
var stateArray = state._data.Cast().ToArray();
lock (this) {
_rnd.SetState(stateArray);
}
}
#endregion
}
}
}