// Copyright (c) Six Labors and contributors.
// Licensed under the Apache License, Version 2.0.

using System.Numerics;
using SixLabors.ImageSharp.PixelFormats;
using Xunit;

namespace SixLabors.ImageSharp.Tests.PixelFormats
{
    public class Byte4Tests
    {
        [Fact]
        public void Byte4_PackedValue()
        {
            Assert.Equal((uint)128, new Byte4(127.5f, -12.3f, 0.5f, -0.7f).PackedValue);
            Assert.Equal((uint)0x1a7b362d, new Byte4(0x2d, 0x36, 0x7b, 0x1a).PackedValue);
            Assert.Equal((uint)0x0, new Byte4(Vector4.Zero).PackedValue);
            Assert.Equal(0xFFFFFFFF, new Byte4(Vector4.One * 255).PackedValue);
        }

        [Fact]
        public void Byte4_ToVector4()
        {
            Assert.Equal(Vector4.One * 255, new Byte4(Vector4.One * 255).ToVector4());
            Assert.Equal(Vector4.Zero, new Byte4(Vector4.Zero).ToVector4());
            Assert.Equal(Vector4.UnitX * 255, new Byte4(Vector4.UnitX * 255).ToVector4());
            Assert.Equal(Vector4.UnitY * 255, new Byte4(Vector4.UnitY * 255).ToVector4());
            Assert.Equal(Vector4.UnitZ * 255, new Byte4(Vector4.UnitZ * 255).ToVector4());
            Assert.Equal(Vector4.UnitW * 255, new Byte4(Vector4.UnitW * 255).ToVector4());
        }

        [Fact]
        public void Byte4_ToScaledVector4()
        {
            // arrange
            var byte4 = new Byte4(Vector4.One * 255);

            // act
            Vector4 actual = byte4.ToScaledVector4();

            // assert
            Assert.Equal(1, actual.X);
            Assert.Equal(1, actual.Y);
            Assert.Equal(1, actual.Z);
            Assert.Equal(1, actual.W);
        }

        [Fact]
        public void Byte4_FromScaledVector4()
        {
            // arrange
            Vector4 scaled = new Byte4(Vector4.One * 255).ToScaledVector4();
            var pixel = default(Byte4);
            uint expected = 0xFFFFFFFF;

            // act
            pixel.FromScaledVector4(scaled);
            uint actual = pixel.PackedValue;

            // assert
            Assert.Equal(expected, actual);
        }

        [Fact]
        public void Byte4_Clamping()
        {
            Assert.Equal(Vector4.Zero, new Byte4(Vector4.One * -1234.0f).ToVector4());
            Assert.Equal(Vector4.One * 255, new Byte4(Vector4.One * 1234.0f).ToVector4());
        }
    }
}