// Copyright (c) Six Labors.
// Licensed under the Six Labors Split License.

using System.Runtime.InteropServices;
using SixLabors.ImageSharp.Formats.Webp;
using SixLabors.ImageSharp.PixelFormats;
using SixLabors.ImageSharp.Tests.TestUtilities;

namespace SixLabors.ImageSharp.Tests.Formats.Webp;

[Trait("Format", "Webp")]
public class WebpCommonUtilsTests
{
    [Fact]
    public void CheckNonOpaque_WithOpaquePixels_Works() => RunCheckNoneOpaqueWithOpaquePixelsTest();

    [Fact]
    public void CheckNonOpaque_WithNoneOpaquePixels_Works() => RunCheckNoneOpaqueWithNoneOpaquePixelsTest();

    [Fact]
    public void CheckNonOpaque_WithOpaquePixels_WithHardwareIntrinsics_Works()
        => FeatureTestRunner.RunWithHwIntrinsicsFeature(RunCheckNoneOpaqueWithOpaquePixelsTest, HwIntrinsics.AllowAll);

    [Fact]
    public void CheckNonOpaque_WithOpaquePixels_WithoutSse2_Works()
        => FeatureTestRunner.RunWithHwIntrinsicsFeature(RunCheckNoneOpaqueWithOpaquePixelsTest, HwIntrinsics.DisableHWIntrinsic);

    [Fact]
    public void CheckNonOpaque_WithOpaquePixels_WithoutAvx2_Works()
        => FeatureTestRunner.RunWithHwIntrinsicsFeature(RunCheckNoneOpaqueWithOpaquePixelsTest, HwIntrinsics.DisableAVX2);

    [Fact]
    public void CheckNonOpaque_WithNoneOpaquePixels_WithHardwareIntrinsics_Works()
        => FeatureTestRunner.RunWithHwIntrinsicsFeature(RunCheckNoneOpaqueWithNoneOpaquePixelsTest, HwIntrinsics.AllowAll);

    [Fact]
    public void CheckNonOpaque_WithNoneOpaquePixels_WithoutSse2_Works()
        => FeatureTestRunner.RunWithHwIntrinsicsFeature(RunCheckNoneOpaqueWithNoneOpaquePixelsTest, HwIntrinsics.DisableHWIntrinsic);

    [Fact]
    public void CheckNonOpaque_WithNoneOpaquePixels_WithoutAvx2_Works()
        => FeatureTestRunner.RunWithHwIntrinsicsFeature(RunCheckNoneOpaqueWithNoneOpaquePixelsTest, HwIntrinsics.DisableAVX2);

    private static void RunCheckNoneOpaqueWithNoneOpaquePixelsTest()
    {
        // arrange
        byte[] rowBytes =
        [
            122, 120, 101, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            122, 120, 101, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            148, 158, 158, 10,
            171, 165, 151, 255,
            209, 208, 210, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 10,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            209, 208, 210, 0,
            174, 183, 189, 255,
            148, 158, 158, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 0,
            148, 158, 158, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            148, 158, 158, 100,
            171, 165, 151, 0,
            209, 208, 210, 100,
            174, 183, 189, 255,
            148, 158, 158, 255
        ];
        ReadOnlySpan<Bgra32> row = MemoryMarshal.Cast<byte, Bgra32>(rowBytes);

        bool noneOpaque;
        for (int length = 8; length < row.Length; length += 8)
        {
            // act
            noneOpaque = WebpCommonUtils.CheckNonOpaque(row);

            // assert
            Assert.True(noneOpaque);
        }

        // One last test with the complete row.
        noneOpaque = WebpCommonUtils.CheckNonOpaque(row);
        Assert.True(noneOpaque);
    }

    private static void RunCheckNoneOpaqueWithOpaquePixelsTest()
    {
        // arrange
        byte[] rowBytes =
        [
            122, 120, 101, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            122, 120, 101, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255,
            148, 158, 158, 255,
            171, 165, 151, 255,
            209, 208, 210, 255,
            174, 183, 189, 255,
            148, 158, 158, 255
        ];
        ReadOnlySpan<Bgra32> row = MemoryMarshal.Cast<byte, Bgra32>(rowBytes);

        bool noneOpaque;
        for (int length = 8; length < row.Length; length += 8)
        {
            // act
            noneOpaque = WebpCommonUtils.CheckNonOpaque(row[..length]);

            // assert
            Assert.False(noneOpaque);
        }

        // One last test with the complete row.
        noneOpaque = WebpCommonUtils.CheckNonOpaque(row);
        Assert.False(noneOpaque);
    }
}