namespace Prism.UnitTests
{
    public class AlphasTests : UnitTestSharp.TestFixture
    {
        public class ColorAmountTests : UnitTestSharp.TestFixture
        {
            public void EqualAlphas_LeaveTheAmountAlone()
            {
                CheckEqual(0.25, Alphas.ColorAmount(0.5, 0.5, 0.25));
            }

            public void ATransparentStart_MovesAllTheWayToTheEnd()
            {
                CheckEqual(1.0, Alphas.ColorAmount(0, 1, 0.5));
            }

            public void ATransparentEnd_StaysAtTheStart()
            {
                CheckEqual(0.0, Alphas.ColorAmount(1, 0, 0.5));
            }

            public void UnequalAlphas_WeighEachEndByItsAlpha()
            {
                CheckEqual(0.75, Alphas.ColorAmount(0.25, 0.75, 0.5));
            }

            public void BothTransparent_LeaveTheAmountAlone()
            {
                CheckEqual(0.5, Alphas.ColorAmount(0, 0, 0.5));
            }

            public void AmountZero_IsZeroEvenFromATransparentStart()
            {
                CheckEqual(0.0, Alphas.ColorAmount(0, 1, 0));
            }

            public void AmountOne_IsOneEvenToATransparentEnd()
            {
                CheckEqual(1.0, Alphas.ColorAmount(1, 0, 1));
            }

            public void ANegativeAlpha_CountsAsTransparent()
            {
                CheckEqual(1.0, Alphas.ColorAmount(-1, 1, 0.5));
                CheckEqual(0.0, Alphas.ColorAmount(1, -1, 0.5));
            }
        }
    }
}