#nullable enable
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using Microsoft.Extensions.DependencyInjection;
 
namespace Microsoft.Maui.Hosting.Internal
{
	sealed class MauiHandlersFactory : MauiFactory, IMauiHandlersFactory
	{
		readonly ConcurrentDictionary<Type, Type> _serviceCache = new ConcurrentDictionary<Type, Type>();
 
		readonly RegisteredHandlerServiceTypeSet _registeredHandlerServiceTypeSet;
 
		public MauiHandlersFactory(IMauiHandlersCollection collection)
			: base(collection)
		{
			_registeredHandlerServiceTypeSet = RegisteredHandlerServiceTypeSet.GetInstance(collection);
		}
 
		public IElementHandler? GetHandler(Type type)
			=> GetService(GetVirtualViewHandlerServiceType(type)) as IElementHandler;
 
		public IElementHandler? GetHandler<T>() where T : IElement
			=> GetHandler(typeof(T));
 
		[return: DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
		public Type? GetHandlerType(Type iview)
		{
			InternalCollection.TryGetService(GetVirtualViewHandlerServiceType(iview), out ServiceDescriptor? serviceDescriptor);
 
			return serviceDescriptor?.ImplementationType;
		}
 
		public IMauiHandlersCollection GetCollection() => (IMauiHandlersCollection)InternalCollection;
 
		private Type GetVirtualViewHandlerServiceType(Type type)
			=> _serviceCache.GetOrAdd(type, _registeredHandlerServiceTypeSet.ResolveVirtualViewToRegisteredHandlerServiceType);
	}
}