using MoonTools.FastCollections;
using System;
using System.Collections.Generic;

namespace Encompass
{
    internal class ComponentBitSet
    {
        Dictionary<int, BitSet512> entities = new Dictionary<int, BitSet512>();
        Dictionary<Type, int> TypeToIndex { get; }

        public ComponentBitSet(Dictionary<Type, int> typeToIndex)
        {
            TypeToIndex = typeToIndex;
        }

        public void Clear()
        {
            entities.Clear();
        }

        public void AddEntity(int entityID)
        {
            entities.Add(entityID, BitSet512.Zero);
        }

        public void Set<TComponent>(int entityID) where TComponent : struct, IComponent
        {
            if (!entities.ContainsKey(entityID)) { AddEntity(entityID); }
            entities[entityID] = entities[entityID].Set(TypeToIndex[typeof(TComponent)]);
        }

        public void RemoveComponent<TComponent>(int entityID) where TComponent : struct, IComponent
        {
            if (entities.ContainsKey(entityID))
            {
                entities[entityID] = entities[entityID].UnSet(TypeToIndex[typeof(TComponent)]);
            }
        }

        public void RemoveEntity(int entityID)
        {
            if (entities.ContainsKey(entityID))
            {
                entities.Remove(entityID);
            }
        }

        public BitSet512 EntityBitArray(int entityID)
        {
            return entities.ContainsKey(entityID) ? entities[entityID] : BitSet512.Zero;
        }
    }
}