Query/AppConv/Utils/SI.cs

using System;
using System.Collections.Generic;
using AppConv.General;

namespace AppConv.Utils;

static class SI {
	private static readonly List<Tuple<string, string, int>> Factors = [
		new Tuple<string, string, int>("yotta", "Y", 24),
		new Tuple<string, string, int>("zetta", "Z", 21),
		new Tuple<string, string, int>("exa", "E", 18),
		new Tuple<string, string, int>("peta", "P", 15),
		new Tuple<string, string, int>("tera", "T", 12),
		new Tuple<string, string, int>("giga", "G", 9),
		new Tuple<string, string, int>("mega", "M", 6),
		new Tuple<string, string, int>("kilo", "k", 3),
		new Tuple<string, string, int>("hecto", "h", 2),
		new Tuple<string, string, int>("deca", "da", 1),
		new Tuple<string, string, int>("deci", "d", -1),
		new Tuple<string, string, int>("centi", "c", -2),
		new Tuple<string, string, int>("milli", "m", -3),
		new Tuple<string, string, int>("micro", "μ", -6),
		new Tuple<string, string, int>("nano", "n", -9),
		new Tuple<string, string, int>("pico", "p", -12),
		new Tuple<string, string, int>("femto", "f", -15),
		new Tuple<string, string, int>("atto", "a", -18),
		new Tuple<string, string, int>("zepto", "z", -21),
		new Tuple<string, string, int>("yocto", "y", -24)
	];

	public static void AddSupport<T>(T unitObject, string[] unitShortNames, string[] unitLongNames, DecimalUnitConverterBase<T>.DecimalFuncMap funcFrom, DecimalUnitConverterBase<T>.DecimalFuncMap funcTo, DecimalUnitConverterBase<T>.NameMap nameMap) where T : struct {
		int enumCounter = 1000 + Factors.Count * (int) (object) unitObject;

		Func<decimal, decimal> convertFrom = funcFrom[unitObject];
		Func<decimal, decimal> convertTo = funcTo[unitObject];

		foreach ((string unitLongNamePrefix, string unitShotNamePrefix, int exponent) in Factors) {
			T enumObject = (T) (object) enumCounter++;

			foreach (string unitShortName in unitShortNames) {
				nameMap.Add(unitShotNamePrefix + unitShortName, enumObject);
			}

			foreach (string unitLongName in unitLongNames) {
				nameMap.Add(unitLongNamePrefix + unitLongName, enumObject);
			}

			funcFrom.Add(enumObject, val => convertFrom(val) * (decimal) Math.Pow(10, -exponent));
			funcTo.Add(enumObject, val => convertTo(val) * (decimal) Math.Pow(10, exponent));
		}
	}

	public static void AddSupportCustom<T>(T unitObject, string[] unitShortNames, string[] unitLongNames, DecimalUnitConverterBase<T>.DecimalFuncMap funcFrom, DecimalUnitConverterBase<T>.DecimalFuncMap funcTo, DecimalUnitConverterBase<T>.NameMap nameMap, ExtededProperties extendedProps) where T : struct {
		int enumCounter = 1000 + Factors.Count * (int) (object) unitObject;

		Func<decimal, decimal> convertFrom = funcFrom[unitObject];
		Func<decimal, decimal> convertTo = funcTo[unitObject];

		foreach ((string unitLongNamePrefix, string unitShortNamePrefix, int exponent) in Factors) {
			if (extendedProps.FactorPredicate != null && !extendedProps.FactorPredicate(exponent)) {
				continue;
			}

			T enumObject = (T) (object) enumCounter++;

			foreach (string unitShortName in unitShortNames) {
				nameMap.Add(unitShortNamePrefix + unitShortName, enumObject);
			}

			foreach (string unitLongName in unitLongNames) {
				nameMap.Add(unitLongNamePrefix + unitLongName, enumObject);
			}

			Func<decimal> genFrom = extendedProps.FromFunctionGenerator(exponent);
			Func<decimal> genTo = extendedProps.ToFunctionGenerator(exponent);

			funcFrom.Add(enumObject, val => convertFrom(val) * genFrom());
			funcTo.Add(enumObject, val => convertTo(val) * genTo());
		}
	}

	internal sealed class ExtededProperties {
		public required Predicate<int> FactorPredicate { get; init; }
		public required Func<int, Func<decimal>> FromFunctionGenerator { get; init; }
		public required Func<int, Func<decimal>> ToFunctionGenerator { get; init; }
	}
}