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

using System.Buffers;
using BenchmarkDotNet.Attributes;

using SixLabors.ImageSharp.Memory;
using SixLabors.ImageSharp.PixelFormats;

// ReSharper disable InconsistentNaming
namespace SixLabors.ImageSharp.Benchmarks.Bulk;

public abstract class ToRgba32Bytes<TPixel>
    where TPixel : unmanaged, IPixel<TPixel>
{
    private IMemoryOwner<TPixel> source;

    private IMemoryOwner<byte> destination;

    private Configuration configuration;

    [Params(16, 128, 1024)]
    public int Count { get; set; }

    [GlobalSetup]
    public void Setup()
    {
        this.configuration = Configuration.Default;
        this.source = this.configuration.MemoryAllocator.Allocate<TPixel>(this.Count);
        this.destination = this.configuration.MemoryAllocator.Allocate<byte>(this.Count * 4);
    }

    [GlobalCleanup]
    public void Cleanup()
    {
        this.source.Dispose();
        this.destination.Dispose();
    }

    // [Benchmark]
    public void Naive()
    {
        Span<TPixel> s = this.source.GetSpan();
        Span<byte> d = this.destination.GetSpan();

        for (int i = 0; i < this.Count; i++)
        {
            TPixel c = s[i];
            int i4 = i * 4;
            Rgba32 rgba = c.ToRgba32();
            d[i4] = rgba.R;
            d[i4 + 1] = rgba.G;
            d[i4 + 2] = rgba.B;
            d[i4 + 3] = rgba.A;
        }
    }

    [Benchmark(Baseline = true)]
    public void CommonBulk() =>
        new PixelOperations<TPixel>().ToRgba32Bytes(
            this.configuration,
            this.source.GetSpan(),
            this.destination.GetSpan(),
            this.Count);

    [Benchmark]
    public void OptimizedBulk() =>
        PixelOperations<TPixel>.Instance.ToRgba32Bytes(
            this.configuration,
            this.source.GetSpan(),
            this.destination.GetSpan(),
            this.Count);
}

public class ToRgba32Bytes_FromRgba32 : ToRgba32Bytes<Rgba32>
{
}

public class ToRgba32Bytes_FromArgb32 : ToRgba32Bytes<Argb32>
{
}

public class ToRgba32Bytes_FromBgra32 : ToRgba32Bytes<Bgra32>
{
}