using Qrakhen.Qamp.Core.Collections.Abstractions;

namespace Qrakhen.Qamp.Core.Collections;

/// <summary>
///     Dynamic Pointer able to point to any object implementing the <see cref="IGetSet{long, TValue}"/> interface. 
/// </summary>
public class Pointer<T>
{
   protected IGetSet<long, T> Target;
   public long Cursor;

   public T Current {
      get => Get();
      set => Set(value);
   }

   public Pointer(IGetSet<long, T> target, long pointer = 0)
   {
      Target = target;
      Cursor = pointer;
   }

   public Pointer<T> Branch(long delta = 0)
   {
      return new Pointer<T>(Target, Cursor + delta);
   }

   /// <summary>
   ///     Returns the next item from <see cref="Target"/> and increases the pointer by 1.
   /// </summary>
   public T Next() => Target.Get(Cursor++);

   /// <summary>
   ///     Sets the value of <see cref="Target"/> RELATIVE from the current position (<paramref name="delta"/>).
   /// </summary>
   public void Set(long delta, T value) => Target.Set(Cursor + delta, value);

   /// <summary>
   ///     Sets the value of <see cref="Target"/> at the current <see cref="Cursor"/> location. 
   /// </summary>
   public void Set(T value) => Set(Cursor, value);

   /// <summary>
   ///     Gets the value of <see cref="Target"/> RELATIVE from the current position (<paramref name="delta"/>). 
   /// </summary>
   public T Get(long delta) => Target.Get(Cursor + delta);

   /// <summary>
   ///     Gets the value of <see cref="Target"/> at the current <see cref="Cursor"/> location. 
   /// </summary>
   public T Get() => Get(Cursor);

   public override string ToString()
   {
      return $"&{Cursor:X4}={Current}";
   }
}