internal class ComponentRequirements
    {
        public ComponentRequirements()
        {
            requiredTypes = new List<Type>();
        }

        private List<Type> requiredTypes;

        public bool IsEmpty { get { return !requiredTypes.Any(); } }

        public bool ComponentIsRequired<TComponent>() where TComponent : IComponent
        {
            return requiredTypes.Contains(typeof(TComponent));
        }

        public void AddRequiredType<TComponent>() where TComponent : IComponent
        {
            requiredTypes.Add(typeof(TComponent));
        }

        public bool ValidateEntity(Type[] entityComponents)
        {
            for (int i = 0; i < requiredTypes.Count; i++)
            {
                if (!entityComponents.Contains(requiredTypes[i]))
                {
                    return false;
                }
            }

            return true;
        }
    }