laatzen/Common/CommonConsole/Unit.cs

namespace CommonConsole
{
    using CommonConsole.JsonConverters;

    using Newtonsoft.Json;

    using System;
    using System.Collections.Generic;
    using System.Linq;

    public abstract class Unit
    {
        public const int MsInSec = 1000;
        public const int SecInMin = 60;
        public const int MinInH = 60;
        public const int HInDay = 24;
        public const int MlInL = 1000;
        public const int LInm3 = 1000;
        public const int PInBar = 100000;
        public const int MAInH = 1000;

        protected double value;

        public virtual object Base { get; set; }

        public override string ToString() 
            => this.value.ToString();

        public override bool Equals(object obj) 
            => this.value.Equals(obj);

        public override int GetHashCode()
            => this.value.GetHashCode();

        public static implicit operator double (Unit @base)
            => @base?.value ?? default(double);

        public static implicit operator double? (Unit @base)
            => @base?.value;

        public static implicit operator Unit(string unitName)
        {
            try
            {
                var valueType = Type.GetType(
                    typeName: $"CommonConsole.{unitName}",
                    throwOnError: false,
                    ignoreCase: true);
                var instance = Activator.CreateInstance(valueType);

                if (instance is Unit unit)
                {
                    return unit;
                }
            }
            catch (Exception e)
            {
                // TODO: Handle exceptions.
            }

            return default(Unit);
        }

        public static IEnumerable<string> MessurementUnits
            => typeof(Unit)
                .Assembly
                .GetTypes()
                .Where(x => typeof(Unit).IsAssignableFrom(x) && !x.IsAbstract)
                .Select(x => x.Name);
    }

    [JsonConverter(typeof(CurrentConverter))]
    public class Current : Unit
    {
        public double MiliampereHours
        {
            get => this.AmpereHours * MAInH;
            set => this.AmpereHours = value / MAInH;
        }

        public double AmpereHours
        {
            get => this.value;
            set => this.value = value;
        }

        public static implicit operator Current(double x)
            => new Current { value = x };

        public static implicit operator Current(double? x)
            => new Current { value = x ?? 0 };
    }

    [JsonConverter(typeof(FlowConverter))]
    public class Flow : Unit
    {
        public double CubicMeterInHour
        {
            get => this.value;
            set => this.value = value;
        }

        public double LiterInMinute
        {
            get => this.CubicMeterInHour / MinInH * LInm3;
            set => this.CubicMeterInHour = value * MinInH / LInm3;
        }

        public static implicit operator Flow(double x)
            => new Flow { value = x };

        public static implicit operator Flow(double? x)
            => new Flow { value = x ?? 0 };
    }

    [JsonConverter(typeof(PressureConverter))]
    public class Pressure : Unit
    {
        public double Pascal
        {
            get => this.value;
            set => this.value = value;
        }

        public double Bar
        {
            get => this.Pascal / PInBar;
            set => this.Pascal = value * PInBar;
        }

        public static implicit operator Pressure(double x)
            => new Pressure { value = x };

        public static implicit operator Pressure(double? x)
            => new Pressure { value = x ?? 0 };
    }

    [JsonConverter(typeof(TemperatureConverter))]
    public class Temperature : Unit
    {
        public double Celsius
        {
            get => this.value;
            set => this.value = value;
        }

        public static implicit operator Temperature(double x)
            => new Temperature { value = x };

        public static implicit operator Temperature(double? x)
            => new Temperature { value = x ?? 0 };
    }

    [JsonConverter(typeof(TimeConverter))]
    public class Time : Unit
    {
        public double Miliseconds
        {
            get => this.Seconds * MsInSec;
            set => this.Seconds = value / MsInSec;
        }

        public double Seconds
        {
            get => this.value;
            set => this.value = value;
        }

        public double Minutes
        {
            get => this.Seconds / SecInMin;
            set => this.Seconds = value * SecInMin;
        }

        public double Hours
        {
            get => this.Minutes / MinInH;
            set => this.Minutes = value * MinInH;
        }

        public double Days
        {
            get => this.Hours / HInDay;
            set => this.Hours = value * HInDay;
        }

        public static implicit operator Time(double x)
            => new Time { value = x };

        public static implicit operator Time(double? x)
            => new Time { value = x ?? 0 };
    }

    [JsonConverter(typeof(VolumeConverter))]
    public class Volume : Unit
    {
        public double Mililiter
        {
            get => this.Liter * MlInL;
            set => this.Liter = value / MlInL;
        }

        public double Liter
        {
            get => this.value * LInm3;
            set => this.value = value / LInm3;
        }

        public double CubicMeter
        {
            get => this.value * this.Factor;
            set => this.value = value / this.Factor;
        }

        public int Factor { get; set; } = 1000;

        public static implicit operator Volume(double x)
            => new Volume { value = x };

        public static implicit operator Volume(double? x)
            => new Volume { value = x ?? 0 };
    }
}