using Microsoft.Extensions.DependencyInjection;

namespace Connected.ServiceModel
{
	internal sealed class Context : IContext, IDisposable
	{
		private CancellationTokenSource _cancellationTokenSource;

		public Context()
		{
			_cancellationTokenSource = new();
		}

		public CancellationToken CancellationToken => _cancellationTokenSource.Token;
		internal IServiceScope? Scope { get; set; }
		private bool IsDisposed { get; set; }

		public T? GetService<T>()
		{
			if (Scope is null)
				return default;

			try
			{
				return Scope.ServiceProvider.GetService<T>();
			}
			catch (ObjectDisposedException)
			{
				return default;
			}
		}

		public object? GetService(Type serviceType)
		{
			if (Scope is null)
				return default;

			return Scope.ServiceProvider.GetService(serviceType);
		}
		private void Dispose(bool disposing)
		{
			if (IsDisposed)
				return;

			if (disposing)
			{
				if (!_cancellationTokenSource.IsCancellationRequested)
					_cancellationTokenSource.Cancel(false);

				Scope?.Dispose();

				_cancellationTokenSource.Dispose();
			}

			IsDisposed = true;
		}

		public void Dispose()
		{
			Dispose(true);
			GC.SuppressFinalize(this);
		}
	}
}