using System;
using System.Collections.Generic;
using UnityEngine;

namespace BitStrap
{
	[Serializable]
	public class Modifiable<T> : IModifiable
	{
		[SerializeField]
		private T originalValue;

		[SerializeField]
		private T modifiedValue;

		private Dictionary<object, T> modifiers = new Dictionary<object, T>();

		private Func<T, T, T> aggregateFunction;

		public T OriginalValue
		{
			get
			{
				return originalValue;
			}
			set
			{
				originalValue = value;
				UpdateModifiedValues();
			}
		}

		public T ModifiedValue
		{
			get
			{
				return modifiedValue;
			}
		}

		public Modifiable(T value, Func<T, T, T> aggregateFunction)
		{
			originalValue = value;
			this.aggregateFunction = aggregateFunction;
			modifiedValue = value;
		}

		public static implicit operator T(Modifiable<T> modifiable)
		{
			return modifiable.modifiedValue;
		}

		public void SetModifier(object context, T modifier)
		{
			modifiers[context] = modifier;
			UpdateModifiedValues();
		}

		public void RemoveModifier(object context)
		{
			modifiers.Remove(context);
			UpdateModifiedValues();
		}

		public void ClearModifiers()
		{
			modifiers.Clear();
			modifiedValue = originalValue;
		}

		public override string ToString()
		{
			return modifiedValue.ToString();
		}

		public void UpdateModifiedValues()
		{
			modifiedValue = originalValue;
			T arg = originalValue;
			DictionaryExtensions.GCFreeEnumerator<object, T> enumerator = modifiers.Each().GetEnumerator();
			while (enumerator.MoveNext())
			{
				T value = enumerator.Current.Value;
				modifiedValue = aggregateFunction(arg, value);
				arg = value;
			}
		}
	}
}