using System.Diagnostics.CodeAnalysis;
using System.Runtime.CompilerServices;

namespace SJK.Functional;

public class Some<T> : IOption<T> 
{
  private readonly T _data;

  private Some(T data)
  {
    _data = data;
  }
  public ref readonly T Value => ref _data; 
  public static Some<T> Of(T data) => new(data);
  // [MethodImpl(MethodImplOptions.AggressiveInlining)]//TODO see if these inporve perfomce in gernral cases
  public TResult Match<TResult>(Func<T, TResult> onSome, Func<TResult> _) =>
    onSome(_data);
// [MethodImpl(MethodImplOptions.AggressiveInlining)]
  public IOption<TResult> Bind<TResult>(Func<T, IOption<TResult>> f) => f(_data);
// [MethodImpl(MethodImplOptions.AggressiveInlining)]
  public IOption<TResult> Map<TResult>(Func<T, TResult> f) => new Some<TResult>(f(_data));
// [MethodImpl(MethodImplOptions.AggressiveInlining)]
  public T Or(T _) => _data;
    public T Or(Func<T> aDefault) => _data;
    public bool HasValue([NotNullWhen(true)]out T? value) => (value = _data) is not null;

    public bool HasValue() => true;
// [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public void Match(Action<T> onSome, Action onNone) => onSome(_data);
    public override string ToString()
    {
        return nameof(Some<T>)+": "+ _data;
    }

    public bool Equals(IOption<T>? other)
    {
      if (other is Some<T> some){
        return _data!.Equals(some._data);
      }
      return false;
    }

}