using MAX.Core.Infrastructure;
using System;
using System.Collections.Concurrent;

namespace MAX.Core.DependencyInjection;

public interface ILazyServiceProvider
{
	object LazyGetService(Type serviceType);
	T LazyGetService<T>();
}

public class LazyServiceProvider : SingleInstance<LazyServiceProvider>, ILazyServiceProvider
{
	protected ConcurrentDictionary<Type, Lazy<object>> CachedServices { get; }
	private LazyServiceProvider()
	{
		CachedServices = new ConcurrentDictionary<Type, Lazy<object>>();
	}
	public virtual T LazyGetService<T>()
	{
		return (T)LazyGetService(typeof(T));
	}

	public virtual object LazyGetService(Type serviceType)
	{
		return GetService(serviceType);
	}
	public virtual object GetService(Type serviceType)
	{
		return CachedServices.GetOrAdd(
			serviceType,
			_ => new Lazy<object>(() => IocManager.Resolve(serviceType))
		).Value;
	}
}