X25519.cs

using System;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Model;
using Waher.Script.Objects;
using Waher.Security.EllipticCurves;
 
namespace Waher.Script.Cryptography.Functions.Ecc
{
    public class X25519 : FunctionMultiVariate
    {
        public X25519(int Start, int Length, Expression Expression)
            : base(new ScriptNode[0], argumentTypes0, Start, Length, Expression)
        {
        }
 
        public X25519(ScriptNode PrivateKey, int Start, int Length, Expression Expression)
            : base(new ScriptNode[] { PrivateKey }, argumentTypes1Normal, Start, Length, Expression)
        {
        }
 
        public override string FunctionName => nameof(X25519);
 
        public override string[] DefaultArgumentNames => new string[] { "PrivateKey" };
 
        public override IElement Evaluate(IElement[] Arguments, Variables Variables)
        {
            int c = Arguments.Length;
 
            if (c == 0)
                return new ObjectValue(new Curve25519());
 
            object Obj = Arguments[0].AssociatedObjectValue;
            if (!(Obj is byte[] PrivateKey))
                PrivateKey = Convert.FromBase64String(Obj?.ToString());
 
            return new ObjectValue(new Curve25519(PrivateKey));
        }
    }
}