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

using BenchmarkDotNet.Attributes;
using SixLabors.ImageSharp.Formats;
using SixLabors.ImageSharp.Tests;
using SDImage = System.Drawing.Image;
using SDSize = System.Drawing.Size;

// ReSharper disable InconsistentNaming
namespace SixLabors.ImageSharp.Benchmarks.Codecs.Jpeg;

/// <summary>
/// Image-specific Jpeg benchmarks
/// </summary>
[Config(typeof(Config.Short))]
public class DecodeJpeg_ImageSpecific
{
    private byte[] jpegBytes;

    private string TestImageFullPath => Path.Combine(TestEnvironment.InputImagesDirectoryFullPath, this.TestImage);

#pragma warning disable SA1115
    [Params(
        TestImages.Jpeg.BenchmarkSuite.Lake_Small444YCbCr,
        TestImages.Jpeg.BenchmarkSuite.BadRstProgressive518_Large444YCbCr,

        // The scaled result for the large image "ExifGetString750Transform_Huge420YCbCr"
        // is almost the same as the result for Jpeg420Exif,
        // which proves that the execution time for the most common YCbCr 420 path scales linearly.
        // TestImages.Jpeg.BenchmarkSuite.ExifGetString750Transform_Huge420YCbCr,
        TestImages.Jpeg.BenchmarkSuite.Jpeg420Exif_MidSizeYCbCr)]

    public string TestImage { get; set; }

    [GlobalSetup]
    public void ReadImages()
        => this.jpegBytes ??= File.ReadAllBytes(this.TestImageFullPath);

    [Benchmark(Baseline = true)]
    public SDSize SystemDrawing()
    {
        using MemoryStream memoryStream = new(this.jpegBytes);
        using SDImage image = SDImage.FromStream(memoryStream);
        return image.Size;
    }

    [Benchmark]
    public Size ImageSharp()
    {
        using MemoryStream memoryStream = new(this.jpegBytes);
        using Image image = Image.Load(new DecoderOptions() { SkipMetadata = true }, memoryStream);
        return new Size(image.Width, image.Height);
    }

    /*
    |                         Method |            TestImage |       Mean |       Error |     StdDev | Ratio | RatioSD | Gen 0 | Gen 1 | Gen 2 |  Allocated |
    |------------------------------- |--------------------- |-----------:|------------:|-----------:|------:|--------:|------:|------:|------:|-----------:|
    | 'Decode Jpeg - System.Drawing' | Jpg/b(...)e.jpg [21] |   5.122 ms |   1.3978 ms |  0.0766 ms |  1.00 |    0.00 |     - |     - |     - |      176 B |
    |     'Decode Jpeg - ImageSharp' | Jpg/b(...)e.jpg [21] |  11.991 ms |   0.2514 ms |  0.0138 ms |  2.34 |    0.03 |     - |     - |     - |    15816 B |
    |                                |                      |            |             |            |       |         |       |       |       |            |
    | 'Decode Jpeg - System.Drawing' | Jpg/b(...)f.jpg [28] |  14.943 ms |   1.8410 ms |  0.1009 ms |  1.00 |    0.00 |     - |     - |     - |      176 B |
    |     'Decode Jpeg - ImageSharp' | Jpg/b(...)f.jpg [28] |  29.759 ms |   1.5452 ms |  0.0847 ms |  1.99 |    0.01 |     - |     - |     - |    16824 B |
    |                                |                      |            |             |            |       |         |       |       |       |            |
    | 'Decode Jpeg - System.Drawing' | Jpg/i(...)e.jpg [43] | 388.229 ms | 382.8946 ms | 20.9877 ms |  1.00 |    0.00 |     - |     - |     - |      216 B |
    |     'Decode Jpeg - ImageSharp' | Jpg/i(...)e.jpg [43] | 276.490 ms | 195.5104 ms | 10.7166 ms |  0.71 |    0.01 |     - |     - |     - | 36022368 B |
     */
}