using NBitcoin.Secp256k1;
using Xunit;

namespace WalletWasabi.Tests.UnitTests.Crypto
{
	public class ScalarTests
	{
		[Fact]
		public void ScalarBehavesAsExpected()
		{
			// Just small scalar tests to showcase some edge cases how the Scalar behaves.
			Assert.True(EC.N.IsOverflow);

			var one = new Scalar(1);
			var nPlusOne = EC.N + one;
			Assert.False(nPlusOne.IsOverflow);
			Assert.Equal(one, nPlusOne);

			var nPlusOneMinusOne = nPlusOne + one.Negate();
			Assert.False(nPlusOne.IsOverflow);
			Assert.Equal(Scalar.Zero, nPlusOneMinusOne);

			var nMinusOne = EC.N + one.Negate();
			Assert.False(nMinusOne.IsOverflow);
			Assert.True(nMinusOne.IsHigh);

			var largest = new Scalar(uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue);
			Assert.True(largest.IsOverflow);

			var two = one + one;
			Assert.Equal(new Scalar(2), two);
			Assert.Equal(one, two + one.Negate());
			Assert.Equal(Scalar.Zero, two + one.Negate() + one.Negate());
		}
	}
}
