/Source/facebook.Linq/Web/FacebookSession.cs

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Configuration;

using facebook.Linq;

using System.Diagnostics;

using facebook;

namespace facebook.Web

{



	public class FacebookContext

	{

		FacebookContext(HttpContext context)

		{

			Context = context;

		}



		HttpContext Context;

		public static FacebookContext Get(HttpContext context)

		{

			if (context == null)

				return null;

			var fc = context.Items["FacebookContext"] as FacebookContext;

			if (fc == null)

			{

				fc = new FacebookContext(context);

				context.Items["FacebookContext"] = fc;

			}

			return fc;

		}



		public static FacebookContext Current

		{

			get

			{

				return Get(HttpContext.Current);

			}

		}



		FacebookSession _Session;

		public FacebookSession Session

		{

			get

			{

				if (_Session == null)

				{

					var session = Context.Session;

					if (session == null)

						return null;

					_Session = session["FacebookSession"] as FacebookSession;

					if(_Session==null)

					{

						_Session = new FacebookSession();

						session["FacebookSession"] = _Session;

					}

				}

				return _Session;

			}

		}



		public bool TryAuthenticating(bool gotoLoginPageIfNeeded)

		{

			var x = Session.TryAuthenticating(Context.Request);

			if (!x)

				RedirectTopFrame(Facebook.FacebookLoginUrl);

			return x;

		}



		public bool TryAuthenticating()

		{

			return TryAuthenticating(false);

		}





		public static bool HasValidConfiguration

		{

			get

			{

				return Facebook.HasValidConfiguration;

			}

		}



		public static string FacebookLoginUrl

		{

			get

			{

				return Facebook.FacebookLoginUrl;

			}

		}



		internal void RedirectTopFrame(string url)

		{

			var response = Context.Response;

			response.ContentType = "text/html";

			response.Cache.SetNoStore();

			response.Cache.SetCacheability(HttpCacheability.NoCache);

			response.Cache.SetExpires(DateTime.Now.AddDays(-1));



			response.Write("<script type=\"text/javascript\">\n" +

									 "if (parent != self) \n" +

									 "top.location.href = \"" + url + "\";\n" +

									 "else self.location.href = \"" + url + "\";\n" +

									 "</script>");

			response.End();

		}

	}





	public class FacebookSession

	{

		protected internal FacebookSession()

		{

		}



		public static FacebookSession Current

		{

		  get

		  {

				return FacebookContext.Current.Session;

		  }

		}



		

		public string SessionKey { get; set; }



		public long UserID { get; set; }



		public string AuthenticationToken { get; set; }



		public bool IsAuthenticated

		{

			get

			{

				return SessionKey.IsNotNullOrEmpty() && UserID>0;// && AuthenticationToken.IsNotNullOrEmpty();

			}

		}

		

		public bool TryAuthenticating(string fb_sig_session_key, string fb_sig_user, string auth_token)

		{

			if (IsAuthenticated)

				return true;		

			SessionKey = fb_sig_session_key;

			if (fb_sig_user.IsNotNullOrEmpty())

				UserID = Int64.Parse(fb_sig_user);

			AuthenticationToken = auth_token;

			if (IsAuthenticated)

			{

				UpdateApi();

				return true;

			}

			else

				return false;

		}





		void UpdateApi()

		{

			if (_Api != null)

			{

				_Api.ApplicationKey = Facebook.APIKey;

				_Api.Secret = Facebook.Secret;

				_Api.AuthToken = AuthenticationToken;

				_Api.SessionKey = SessionKey;

				_Api.uid = UserID;

			}

		}

		public bool TryAuthenticating(HttpRequest request)

		{

			return TryAuthenticating(request["fb_sig_session_key"], request["fb_sig_user"], request["auth_token"]);

		}



		API _Api;

		public API Api

		{

			get

			{

				if (_Api == null)

				{

					_Api = new API();

					UpdateApi();

				}

				return _Api;

			}

			set

			{

				_Api = value;

			}

		}



		FacebookDataContext _Database;

		public FacebookDataContext Database 

		{

			get

			{

				if (_Database == null)

					_Database = new FacebookDataContext(Api);

				return _Database;

			}

		}

	}







}