Shrlalgo.RvKits/Melskin/Converters/Internal/ValueToRangeWidthConverter.cs

using System.Globalization;
using System.Windows.Data;

namespace Melskin.Converters.Internal;

/// <summary>
/// 该转换器实现了IMultiValueConverter接口，用于将值转换为范围宽度。它主要用于进度条或滑块控件中，根据当前值、最小值和最大值来计算并返回一个宽度值。
/// 通过传入的参数（以字符串形式），可以额外指定边距，该边距会从总宽度中减去。最终返回的宽度基于当前值在最小值与最大值之间的比例，并且考虑了调整后的实际宽度。
/// </summary>
internal class ValueToRangeWidthConverter : IMultiValueConverter
{
    public static readonly ValueToRangeWidthConverter Instance = new();
    public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
    {
        var paramStr = parameter as string;
        _ = double.TryParse(paramStr, out var margin);

        var minimum = (double)values[0];
        var maximum = (double)values[1];
        var currentValue = (double)values[2];
        var width = (double)values[3];
        var actualWidth = width - 2 * margin;

        if (actualWidth < 0)
        {
            actualWidth = 0;
        }
        if (currentValue < minimum)
        {
            return 0;
        }
        if (currentValue > maximum)
        {
            return actualWidth;
        }

        return ((currentValue - minimum) / (maximum - minimum)) * actualWidth;
    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}