using Qrakhen.Qamp.Core.Collections.Abstractions;

namespace Qrakhen.Qamp.Core.Collections;

/// <summary>
///     Stack-like implementation with a few added features like seeking and setting values.
/// </summary>
/// <typeparam name="T"></typeparam>
public class StackLike<T> : Expander<T>,
    IPush<long, T>,
    IPop<T>,
    ISeekable<long, T>,
    IPeekable<T>,
    IToArray<T>
{
   public long Position => Count;

   public T this[int position] {
      get => Data[position];
      set => Data[position] = value;
   }

   public StackLike(int capacity = 0x10)
   {
      Data = new T[capacity];
      Count = 0;
   }

   public StackLike(IEnumerable<T> data)
   {
      Data = data.ToArray();
      Count = 0;
   }

   public long Push(T value) => Add(value);

   public T Pop() => Data[--Count];

   public T Seek(long position)
   {
      Count = position;
      return this[Count];
   }

   public T Peek(int delta = -1) => Data[Count + delta];

   public bool CanPeek(int delta = 0)
       => Count + delta > -1 && Count + delta < Count;

   /// <summary>
   ///     Decimates this stack down to the given position, overwriting everything beyond that when pushing in the future.
   /// </summary>
   public void Decimate(long position)
   {
      Count = position;
   }

   public T[] ToArray() => Data.ToArray();
}