using System.Collections.Concurrent;

namespace Connected.Middleware;

internal class ComponentMiddlewareService : IComponentMiddlewareService
{
	public ComponentMiddlewareService()
	{
		Middleware = new();
	}

	private ConcurrentDictionary<string, List<Type>> Middleware { get; }

	public void Add<TMiddleware, TComponent>()
	{
		var componentName = typeof(TComponent).FullName;

		if (string.IsNullOrEmpty(componentName))
			throw new ArgumentException(null, nameof(TMiddleware));

		if (Middleware.TryGetValue(componentName, out List<Type>? items))
		{
			//TODO: sort by priority so multiple inheritance would work 
			items.Add(typeof(TMiddleware));
		}
		else
			Middleware.TryAdd(componentName, new List<Type> { typeof(TMiddleware) });
	}

	public Type? Select<TComponent>()
	{
		var typeName = typeof(TComponent).FullName;

		if (string.IsNullOrEmpty(typeName))
			throw new ArgumentException(null, nameof(TComponent));

		if (Middleware.TryGetValue(typeName, out List<Type>? items) && items is not null && items.Any())
			return items[0];

		return null;
	}
}