#nullable enable // Auto-generated code requires an explicit '#nullable' directive in source.
#define Sum

using static System.Math;
using System.Text.Json;
using System.Text.Json.Serialization;
using InnovEnergy.Lib.Utils;

namespace InnovEnergy.Lib.Units;

using T = Current;

public readonly partial struct Current
{
    public Decimal Value { get; }
    public override String ToString() => Value.RoundToSignificantDigits(Units.DisplaySignificantDigits) + Unit;
    
    // scalar multiplication

    public static T operator *(Decimal scalar, T t) => new T(scalar * t.Value);
    public static T operator *(T t, Decimal scalar) => new T(scalar * t.Value);
    public static T operator /(T t, Decimal scalar) => new T(t.Value / scalar);
    
    // parallel
    
    #if Sum
    
    public static T operator |(T left, T right) => new T(left.Value + right.Value);
    public static T operator -(T t)             => new T(-t.Value);
    
    #elif Mean
    
    public static T operator |(T left, T right) => new T((left.Value + right.Value)/2m);
    
    #elif Equal
    
    public static T operator |(T left, T right)
    {
        var d = Max(Abs(left.Value), Abs(right.Value));

        if (d == 0m)
            return new T(0m);

        var relativeError = Abs(left.Value - right.Value) / d;

        const Decimal maxRelativeError = 0.05m;
        
        if (relativeError > maxRelativeError)
            throw new Exception($"{nameof(left)} and {nameof(right)} must be approximately equal.\n" +
                                $"Difference > {maxRelativeError * 100}% detected\n" +
                                $"{nameof(left)} : {left}\n" +
                                $"{nameof(right)}: {right}");

        return new T((left.Value + right.Value) / 2m);
    }    
    #endif

    // compare

    public static Boolean operator ==(T left, T right) => left.Value == right.Value;
    public static Boolean operator !=(T left, T right) => left.Value != right.Value;
    public static Boolean operator > (T left, T right) => left.Value >  right.Value;
    public static Boolean operator < (T left, T right) => left.Value <  right.Value;
    public static Boolean operator >=(T left, T right) => left.Value >= right.Value;
    public static Boolean operator <=(T left, T right) => left.Value <= right.Value;

    // conversion

    public static implicit operator T(Decimal d) => new T(d);
    public static implicit operator T(Double d)  => new T((Decimal)d);
    public static implicit operator T(Int32 i)   => new T(i);
    public static implicit operator Decimal(T t) => t.Value;

    // equality

    public Boolean Equals(T other) => Value == other.Value;
    public override Boolean Equals(Object? obj) => obj is T other && Equals(other);
    public override Int32 GetHashCode() => Value.GetHashCode();

}


internal class CurrentConverter : JsonConverter<Current>
{
    public override Current Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
    {
        return new Current(reader.GetDecimal());
    }

    public override void Write(Utf8JsonWriter writer, Current value, JsonSerializerOptions options)
    {
        var rounded = value.Value.RoundToSignificantDigits(Units.JsonSignificantDigits);

        writer.WriteNumberValue(rounded);
    }
}