namespace Acme Application Authorization using System using System Sec

namespace Acme.Application.Authorization
{
	using System;
	using System.Security.Claims;

	/// <summary>
	/// Represents an action that can be performed on a resource.
	/// </summary>
	public interface IResourceAction
	{
		/// <summary>
		/// Creates a claim corresponding to this action.
		/// </summary>
		/// <returns>
		/// A claim that the principal is allowed to perform the action
		/// defined by this object.
		/// </returns>
		Claim ToClaim();

		/// <summary>
		/// Gets the action name.
		/// </summary>
		string Action { get; }

		/// <summary>
		/// Gets the resource name.
		/// </summary>
		string Resource { get; }
	}

	/// <summary>
	/// Represents an action that can be performed on a resource.
	/// </summary>
	/// <remarks>
	/// The declaring class of a concrete descendant of this class
	/// specifies the resource.
	/// </remarks>
	/// <typeparam name="TAction">
	/// A class representing a concrete action.
	/// </typeparam>
	public abstract class ResourceAction<TAction> : IResourceAction
		where TAction : IResourceAction, new()
	{
		/// <summary>
		/// A claim corresponding to this action.
		/// </summary>
		public static Claim Claim = new TAction().ToClaim();

		/// <summary>
		/// Gets the action name.
		/// </summary>
		public string Action
		{
			get
			{
				return GetType().Name.ToLowerInvariant();
			}
		}

		/// <summary>
		/// Gets the resource name.
		/// </summary>
		public string Resource
		{
			get
			{
				Type resourceType = GetType().DeclaringType;
				if (resourceType == null)
				{
					throw new InvalidOperationException(
						"The resource type could not be determined from the action type.");
				}

				return ResourceAuthorization.Resource.Prefix + resourceType.Name.ToLowerInvariant();
			}
		}

		/// <summary>
		/// Creates a claim corresponding to this action.
		/// </summary>
		/// <returns>
		/// A claim that the principal is allowed to perform the action defined by this object.
		/// </returns>
		public Claim ToClaim()
		{
			return new Claim(Resource, Action);
		}
	}

	/// <summary>
	/// Defines available resources and their corresponding actions.
	/// </summary>
	/// <remarks>
	/// <example>
	/// Adding claims
	///	<code>
	///	identity.AddClaim(Resource.Missiles.Launch.Claim);
	///	</code>
	/// </example>
	/// <example>
	/// Requiring permissions declaratively
	///	<code>
	///	[ResourceAuthorize(typeof(Resource.Missiles.Launch))]
	///	public void ControllerAction() {}
	///	</code>
	/// </example>
	/// </remarks>
	public static class Resource
	{
		/// <summary>
		/// The standard prefix of resource names.
		/// </summary>
		public const string Prefix = "acme:resouce:";

		/// <summary>
		/// Nuclear missiles.
		/// </summary>
		public static class Missiles
		{
			/// <summary>
			/// The user may launch missiles.
			/// </summary>
			public sealed class Launch : ResourceAction<Launch>
			{
			}
		}
	}

	/*
	public class ResourceAuthorizeAttribute : AuthorizeAttribute
	{
		private readonly string _action;
		private readonly string _resource;

		/// <summary>
		/// Initializes a new instance of <see cref="ResourceAuthorizeAttribute"/>
		/// with the specified resource and acrion.
		/// </summary>
		/// <param name="resourceActionType">
		/// The type describing the resource-action pair.
		/// Must be of the form <c>Resource.YourResource.YourAction</c>.
		/// See the nested classes of the <see cref="Resource"/> class.
		/// </param>
		public ResourceAuthorizeAttribute(Type resourceActionType)
		{
			var ra = (IResourceAction)Activator.CreateInstance(resourceActionType);
			_action = ra.Action;
			_resource = ra.Resource;
		}

		...
	}
	*/
}