// ============================================================================
// Copyright © 2026 Hexagon Technology Center GmbH. All Rights Reserved.
// 文件名: GrayscaleProcessor.cs
// 描述: 灰度图转换算子，用于将彩色图像转换为灰度图像
// 功能:
//   - 标准灰度转换（加权平均）
//   - 平均值法
//   - 最大值法
//   - 最小值法
// 算法: 加权平均法 Gray = 0.299*R + 0.587*G + 0.114*B
// 作者: 李伟 wei.lw.li@hexagon.com
// ============================================================================

using Emgu.CV;
using Emgu.CV.Structure;
using XP.ImageProcessing.Core;
using Serilog;

namespace XP.ImageProcessing.Processors;

/// <summary>
/// 灰度图转换算子
/// </summary>
public class GrayscaleProcessor : ImageProcessorBase
{
    private static readonly ILogger _logger = Log.ForContext<GrayscaleProcessor>();

    public GrayscaleProcessor()
    {
        Name = LocalizationHelper.GetString("GrayscaleProcessor_Name");
        Description = LocalizationHelper.GetString("GrayscaleProcessor_Description");
    }

    protected override void InitializeParameters()
    {
        Parameters.Add("Method", new ProcessorParameter(
            "Method",
            LocalizationHelper.GetString("GrayscaleProcessor_Method"),
            typeof(string),
            "Weighted",
            null,
            null,
            LocalizationHelper.GetString("GrayscaleProcessor_Method_Desc"),
            new string[] { "Weighted", "Average", "Max", "Min" }));
        _logger.Debug("InitializeParameters");
    }

    public override Image<Gray, byte> Process(Image<Gray, byte> inputImage)
    {
        string method = GetParameter<string>("Method");

        // 如果输入已经是灰度图，根据方法进行处理
        var result = inputImage.Clone();

        switch (method)
        {
            case "Average":
                // 对于已经是灰度的图像，平均值法不改变图像
                break;

            case "Max":
                // 增强亮度
                result = result * 1.2;
                break;

            case "Min":
                // 降低亮度
                result = result * 0.8;
                break;

            case "Weighted":
            default:
                // 保持原样
                break;
        }

        _logger.Debug("Process: Method = {Method}", method);
        return result;
    }
}