Add new reference system

src/Discord.Net.Net45/Discord.Net.csproj

@@ -223,6 +223,9 @@
     <Compile Include="..\Discord.Net\Helpers\Mention.cs">
       <Link>Helpers\Mention.cs</Link>
     </Compile>
+    <Compile Include="..\Discord.Net\Helpers\Reference.cs">
+      <Link>Helpers\Reference.cs</Link>
+    </Compile>
     <Compile Include="..\Discord.Net\Helpers\TaskHelper.cs">
       <Link>Helpers\TaskHelper.cs</Link>
     </Compile>

src/Discord.Net/Helpers/Reference.cs

@@ -0,0 +1,68 @@
+using System;
+
+namespace Discord
+{
+    internal class Reference<T>
+		where T : CachedObject
+    {
+		private Action<T> _onCache, _onUncache;
+		private Func<string, T> _getItem;
+        private string _id;
+		public string Id
+		{
+			get { return _id; }
+			set
+			{
+				_id = value;
+				_value = null;
+			}
+		}
+
+		private T _value;
+		public T Value
+		{
+			get
+			{
+				var v = _value; //A little trickery to make this threadsafe
+				if (v != null && !_value.IsCached)
+				{
+					v = null;
+					_value = null;
+				}
+				if (v == null && _id != null)
+				{
+					v = _getItem(_id);
+					if (v != null)
+						_onCache(v);
+					_value = v;
+				}
+				return v;
+			}
+		}
+
+		public T Load()
+		{
+			return Value; //Used for precaching
+		}
+
+		public void Unload()
+		{
+			if (_onUncache != null)
+			{
+				var v = _value;
+				if (v != null && _onUncache != null)
+					_onUncache(v);
+			}
+		}
+
+		public Reference(Func<string, T> onUpdate, Action<T> onCache = null, Action<T> onUncache = null)
+			: this(null, onUpdate, onCache, onUncache) { }
+		public Reference(string id, Func<string, T> getItem, Action<T> onCache = null, Action<T> onUncache = null)
+		{
+			_id = id;
+			_getItem = getItem;
+			_onCache = onCache;
+			_onUncache = onUncache;
+		}
+	}
+}

src/Discord.Net/Models/CachedObject.cs

@@ -5,6 +5,8 @@
 		protected readonly DiscordClient _client;
 		private bool _isCached;
 
+		internal bool IsCached => _isCached;
+
 		internal CachedObject(DiscordClient client, string id)
 		{
 			_client = client;
@@ -18,18 +20,18 @@
 
 		internal void Cache()
 		{
-			OnCached();
+			LoadReferences();
 			_isCached = true;
 		}
 		internal void Uncache()
 		{
 			if (_isCached)
 			{
-				OnUncached();
+				UnloadReferences();
 				_isCached = false;
 			}
 		}
-		internal abstract void OnCached();
-		internal abstract void OnUncached();
+		internal abstract void LoadReferences();
+		internal abstract void UnloadReferences();
 	}
 }

src/Discord.Net/Models/Channel.cs

@@ -33,19 +33,19 @@ namespace Discord
 		/// <summary> Returns the position of this channel in the channel list for this server. </summary>
 		public int Position { get; private set; }
 		/// <summary> Returns false is this is a public chat and true if this is a private chat with another user (see Recipient). </summary>
-		public bool IsPrivate => _recipientId != null;
+		public bool IsPrivate => _recipient.Id != null;
 		/// <summary> Returns the type of this channel (see ChannelTypes). </summary>
 		public string Type { get; private set; }
 
 		/// <summary> Returns the server containing this channel. </summary>
 		[JsonIgnore]
-		public Server Server { get; private set; }
-		private readonly string _serverId;
+		public Server Server => _server.Value;
+		private readonly Reference<Server> _server;
 
 		/// For private chats, returns the target user, otherwise null.
 		[JsonIgnore]
-		public User Recipient { get; private set; }
-		private readonly string _recipientId;
+		public User Recipient => _recipient.Value;
+        private readonly Reference<User> _recipient;
 		
 		/// <summary> Returns a collection of all users with read access to this channel. </summary>
 		[JsonIgnore]
@@ -74,39 +74,35 @@ namespace Discord
 		internal Channel(DiscordClient client, string id, string serverId, string recipientId)
 			: base(client, id)
 		{
-			_serverId = serverId;
-			_recipientId = recipientId;
+			_server = new Reference<Server>(serverId, 
+				x => _client.Servers[x], 
+				x => x.AddChannel(this), 
+				x => x.RemoveChannel(this));
+			_recipient = new Reference<User>(recipientId, 
+				x => _client.Users[x, _server.Id], 
+				x =>
+				{
+					Name = "@" + x.Name;
+					x.GlobalUser.PrivateChannel = this;
+				},
+				x => x.GlobalUser.PrivateChannel = null);
 			_permissionOverwrites = _initialPermissionsOverwrites;
 			_areMembersStale = true;
 
 			//Local Cache
 			_messages = new ConcurrentDictionary<string, Message>();
 		}
-		internal override void OnCached()
+		internal override void LoadReferences()
 		{
 			if (IsPrivate)
-			{
-				var recipient = _client.Users[_recipientId, null];
-				Name = "@" + recipient.Name;
-				recipient.GlobalUser.PrivateChannel = this;
-				Recipient = recipient;
-			}
+				_recipient.Load();
 			else
-			{
-				var server = _client.Servers[_serverId];
-				server.AddChannel(this);
-				Server = server;
-            }
+				_server.Load();
 		}
-		internal override void OnUncached()
+		internal override void UnloadReferences()
 		{
-			var server = Server;
-			if (server != null)
-				server.RemoveChannel(this);
-			
-			var recipient = Recipient;
-			if (recipient != null)
-				recipient.GlobalUser.PrivateChannel = null;
+			_server.Unload();
+			_recipient.Unload();
 			
 			var globalMessages = _client.Messages;
 			var messages = _messages;
@@ -167,7 +163,10 @@ namespace Discord
 		}
 		private void UpdateMembersCache()
 		{
-			_members = Server.Members.Where(x => x.GetPermissions(this)?.ReadMessages ?? false).ToDictionary(x => x.Id, x => x);
+			if (_server.Id != null)
+				_members = Server.Members.Where(x => x.GetPermissions(this)?.ReadMessages ?? false).ToDictionary(x => x.Id, x => x);
+			else
+				_members = new Dictionary<string, User>();
 			_areMembersStale = false;
 		}
 

src/Discord.Net/Models/GlobalUser.cs

@@ -43,8 +43,8 @@ namespace Discord
 		{
 			_users = new ConcurrentDictionary<string, User>();
 		}
-		internal override void OnCached() { }
-		internal override void OnUncached()
+		internal override void LoadReferences() { }
+		internal override void UnloadReferences()
 		{
 			//Don't need to clean _users - they're considered owned by server
 		}

src/Discord.Net/Models/Invite.cs

@@ -21,58 +21,37 @@ namespace Discord
 
 		/// <summary> Returns a URL for this invite using XkcdCode if available or Id if not. </summary>
 		public string Url => API.Endpoints.InviteUrl(XkcdCode ?? Id);
-		
+
 		/// <summary> Returns the user that created this invite. </summary>
 		[JsonIgnore]
-		public User Inviter { get; private set; }
-		[JsonProperty("InviterId")]
-		private readonly string _inviterId;
+		public User Inviter => _inviter.Value;
+        private readonly Reference<User> _inviter;
 
 		/// <summary> Returns the server this invite is to. </summary>
 		[JsonIgnore]
-		public Server Server { get; private set; }
-		[JsonProperty("ServerId")]
-		private readonly string _serverId;
+		public Server Server => _server.Value;
+		private readonly Reference<Server> _server;
 
 		/// <summary> Returns the channel this invite is to. </summary>
 		[JsonIgnore]
-		public Channel Channel { get; private set; }
-		[JsonProperty("ChannelId")]
-		private readonly string _channelId;
+		public Channel Channel => _channel.Value;
+		private readonly Reference<Channel> _channel;
 
 		internal Invite(DiscordClient client, string code, string xkcdPass, string serverId, string inviterId, string channelId)
 			: base(client, code)
 		{
 			XkcdCode = xkcdPass;
-			_serverId = serverId;
-			_inviterId = inviterId;
-			_channelId = channelId;
+			_server = new Reference<Server>(serverId, x => _client.Servers[x] ?? new Server(client, x));
+			_inviter = new Reference<User>(serverId, x => _client.Users[x, _server.Id] ?? new User(client, x, _server.Id));
+			_channel = new Reference<Channel>(serverId, x => _client.Channels[x] ?? new Channel(client, x, _server.Id, null));
 		}
-
-		internal override void OnCached()
+		internal override void LoadReferences()
 		{
-			var server = _client.Servers[_serverId];
-			if (server == null)
-				server = new Server(_client, _serverId);
-			Server = server;
-
-			if (_inviterId != null)
-			{
-				var inviter = _client.Users[_inviterId, _serverId];
-				if (inviter == null)
-					inviter = new User(_client, _inviterId, _serverId);
-				Inviter = inviter;
-			}
-
-			if (_channelId != null)
-			{
-				var channel = _client.Channels[_channelId];
-				if (channel == null)
-					channel = new Channel(_client, _channelId, _serverId, null);
-				Channel = channel;
-			}
+			_server.Load();
+			_inviter.Load();
+			_channel.Load();
 		}
-		internal override void OnUncached() { }
+		internal override void UnloadReferences() { }
 
 		public override string ToString() => XkcdCode ?? Id;
 		

src/Discord.Net/Models/Message.cs

@@ -129,48 +129,36 @@ namespace Discord
 		
 		/// <summary> Returns the server containing the channel this message was sent to. </summary>
 		[JsonIgnore]
-		public Server Server => Channel.Server;
+		public Server Server => _channel.Value.Server;
 		/// <summary> Returns the channel this message was sent to. </summary>
 		[JsonIgnore]
-		public Channel Channel { get; private set; }
-		private readonly string _channelId;
+		public Channel Channel => _channel.Value;
+		private readonly Reference<Channel> _channel;
 
 		/// <summary> Returns true if the current user created this message. </summary>
-		public bool IsAuthor => _client.CurrentUserId == _userId;
+		public bool IsAuthor => _client.CurrentUserId == _user.Id;
 		/// <summary> Returns the author of this message. </summary>
 		[JsonIgnore]
-		public User User { get; private set; }
-		private readonly string _userId;
+		public User User => _user.Value;
+		private readonly Reference<User> _user;
 
 		internal Message(DiscordClient client, string id, string channelId, string userId)
 			: base(client, id)
 		{
-			_channelId = channelId;
-			_userId = userId;
+			_channel = new Reference<Channel>(channelId, x => _client.Channels[x], x => x.AddMessage(this), x => x.RemoveMessage(this));
+			_user = new Reference<User>(userId, x => _client.Users[x]);
 			Attachments = _initialAttachments;
 			Embeds = _initialEmbeds;
 		}
-		internal override void OnCached()
+		internal override void LoadReferences()
 		{
-			//References
-			var channel = _client.Channels[_channelId];
-			channel.AddMessage(this);
-			Channel = channel;
-
-			var user = _client.Users[_userId, channel.Server?.Id];
-			//user.AddMessage(this);
-			User = user;
+			_channel.Load();
+			_user.Load();
 		}
-		internal override void OnUncached()
+		internal override void UnloadReferences()
 		{
-			//References
-			var channel = Channel;
-			if (channel != null)
-				channel.RemoveMessage(this);
-
-			/*var user = User;
-			if (user != null)
-				user.RemoveMessage(this);*/
+			_channel.Unload();
+			_user.Unload();
 		}
 
 		internal void Update(MessageInfo model)

src/Discord.Net/Models/Role.cs

@@ -6,9 +6,7 @@ using System.Linq;
 namespace Discord
 {
 	public sealed class Role : CachedObject
-	{
-		private readonly string _serverId;
-		
+	{		
 		/// <summary> Returns the name of this role. </summary>
 		public string Name { get; private set; }
 		/// <summary> If true, this role is displayed isolated from other users. </summary>
@@ -22,40 +20,35 @@ namespace Discord
 
 		/// <summary> Returns the the permissions contained by this role. </summary>
 		public ServerPermissions Permissions { get; }
-		
+
 		/// <summary> Returns the server this role is a member of. </summary>
 		[JsonIgnore]
-		public Server Server { get; private set; }
+		public Server Server => _server.Value;
+		private readonly Reference<Server> _server;
 
 		/// <summary> Returns true if this is the role representing all users in a server. </summary>
-		public bool IsEveryone => _serverId == null || Id == _serverId;
+		public bool IsEveryone => _server.Id == null || Id == _server.Id;
 		/// <summary> Returns a list of all members in this role. </summary>
 		[JsonIgnore]
-		public IEnumerable<User> Members => IsEveryone ? Server.Members : Server.Members.Where(x => x.HasRole(this));
+		public IEnumerable<User> Members => _server.Id != null ? (IsEveryone ? Server.Members : Server.Members.Where(x => x.HasRole(this))) : new User[0];
 		//TODO: Add local members cache
 
 		internal Role(DiscordClient client, string id, string serverId)
 			: base(client, id)
 		{
-			_serverId = serverId;
+			_server = new Reference<Server>(serverId, x => _client.Servers[x], x => x.AddRole(this), x => x.RemoveRole(this));
 			Permissions = new ServerPermissions(0);
 			Permissions.Lock();
 			Color = new Color(0);
 			Color.Lock();
 		}
-		internal override void OnCached()
+		internal override void LoadReferences()
 		{
-			//References
-			var server = _client.Servers[_serverId];
-			server.AddRole(this);
-			Server = server;
+			_server.Load();
 		}
-		internal override void OnUncached()
+		internal override void UnloadReferences()
 		{
-			//References
-			var server = Server;
-			if (server != null)
-				server.RemoveRole(this);
+			_server.Unload();
         }
 
 		internal void Update(RoleInfo model)

src/Discord.Net/Models/Server.cs

@@ -84,8 +84,8 @@ namespace Discord
 			_bans = new ConcurrentDictionary<string, bool>();
 			_invites = new ConcurrentDictionary<string, Invite>();
 		}
-		internal override void OnCached() { }
-		internal override void OnUncached()
+		internal override void LoadReferences() { }
+		internal override void UnloadReferences()
 		{
 			//Global Cache
 			var globalChannels = _client.Channels;
@@ -210,21 +210,31 @@ namespace Discord
 
 		internal void AddMember(User member)
 		{
-			_members.TryAdd(member.Id, member);
-			foreach (var channel in Channels)
+			if (_members.TryAdd(member.Id, member))
 			{
-				member.AddChannel(channel);
-				channel.InvalidatePermissionsCache(member);
+				if (member.Id == _ownerId)
+					Owner = member;
+
+				foreach (var channel in Channels)
+				{
+					member.AddChannel(channel);
+					channel.InvalidatePermissionsCache(member);
+				}
 			}
         }
 		internal void RemoveMember(User member)
 		{
-			foreach (var channel in Channels)
+			if (_members.TryRemove(member.Id, out member))
 			{
-				member.RemoveChannel(channel);
-				channel.InvalidatePermissionsCache(member);
+				if (member.Id == _ownerId)
+					Owner = null;
+
+				foreach (var channel in Channels)
+				{
+					member.RemoveChannel(channel);
+					channel.InvalidatePermissionsCache(member);
+				}
 			}
-			_members.TryRemove(member.Id, out member);
 		}
 		internal void HasMember(User user) => _members.ContainsKey(user.Id);
 

src/Discord.Net/Models/User.cs

@@ -16,7 +16,7 @@ namespace Discord
 		private ServerPermissions _serverPermissions;
 
 		/// <summary> Returns a unique identifier combining this user's id with its server's. </summary>
-		internal string UniqueId => GetId(Id, _serverId);
+		internal string UniqueId => GetId(Id, _server.Id);
 		/// <summary> Returns the name of this user on this server. </summary>
 		public string Name { get; private set; }
 		/// <summary> Returns a by-name unique identifier separating this user from others with the same name. </summary>
@@ -49,11 +49,12 @@ namespace Discord
 		private DateTime _lastOnline;
 
 		[JsonIgnore]
-		internal GlobalUser GlobalUser { get; private set; }
+		internal GlobalUser GlobalUser => _globalUser.Value;
+		private readonly Reference<GlobalUser> _globalUser;
 
 		[JsonIgnore]
-		public Server Server { get; private set; }
-		private string _serverId;
+		public Server Server => _server.Value;
+        private readonly Reference<Server> _server;
 
 		[JsonIgnore]
 		public Channel VoiceChannel { get; private set; }
@@ -64,7 +65,7 @@ namespace Discord
 
 		/// <summary> Returns a collection of all messages this user has sent on this server that are still in cache. </summary>
 		[JsonIgnore]
-		public IEnumerable<Message> Messages => _client.Messages.Where(x => x.User.Id == Id && x.Server.Id == _serverId);
+		public IEnumerable<Message> Messages => _client.Messages.Where(x => x.User.Id == Id && x.Server.Id == _server.Id);
 
 		/// <summary> Returns a collection of all channels this user is a member of. </summary>
 		[JsonIgnore]
@@ -73,44 +74,41 @@ namespace Discord
 		internal User(DiscordClient client, string id, string serverId)
 			: base(client, id)
 		{
-			_serverId = serverId;
+			_globalUser = new Reference<GlobalUser>(id, 
+				x => _client.GlobalUsers.GetOrAdd(x), 
+				x => x.AddUser(this), 
+				x => x.RemoveUser(this));
+			_server = new Reference<Server>(serverId, 
+				x => _client.Servers[x], 
+				x =>
+				{
+					x.AddMember(this);
+					if (x.Id == _client.CurrentUserId)
+						x.CurrentMember = this;
+                }, 
+				x =>
+				{
+					x.RemoveMember(this);
+					if (x.Id == _client.CurrentUserId)
+						x.CurrentMember = null;
+				});
 			Status = UserStatus.Offline;
-			//_roles = new Dictionary<string, Role>();
 			_channels = new ConcurrentDictionary<string, Channel>();
 			_permissions = new ConcurrentDictionary<string, ChannelPermissions>();
 			_serverPermissions = new ServerPermissions();
-        }
-		internal override void OnCached()
-		{
-			if (_serverId != null)
-			{
-				var server = _client.Servers[_serverId];
-				server.AddMember(this);
-				if (Id == _client.CurrentUserId)
-					server.CurrentMember = this;
-				Server = server;
-			}
-			else
+
+			if (serverId == null)
 				UpdateRoles(null);
-
-			var user = _client.GlobalUsers.GetOrAdd(Id);
-			user.AddUser(this);
-			GlobalUser = user;
 		}
-		internal override void OnUncached()
+		internal override void LoadReferences()
 		{
-			//References
-			var server = Server;
-			if (server != null)
-			{
-				server.RemoveMember(this);
-				if (Id == _client.CurrentUserId)
-					server.CurrentMember = null;
-			}
-
-			var globalUser = GlobalUser;
-			if (globalUser != null)
-				globalUser.RemoveUser(this);
+			_globalUser.Load();
+			_server.Load();
+		}
+		internal override void UnloadReferences()
+		{
+			_globalUser.Unload();
+			_server.Unload();
 		}
 
 		public override string ToString() => Id;
@@ -128,6 +126,7 @@ namespace Discord
 		{
 			if (model.User != null)
 				Update(model.User);
+
 			if (model.JoinedAt.HasValue)
 				JoinedAt = model.JoinedAt.Value;
 			if (model.Roles != null)
@@ -138,6 +137,7 @@ namespace Discord
 		internal void Update(ExtendedMemberInfo model)
 		{
 			Update(model as API.MemberInfo);
+
 			if (model.IsServerDeafened != null)
 				IsServerDeafened = model.IsServerDeafened.Value;
 			if (model.IsServerMuted != null)
@@ -156,9 +156,8 @@ namespace Discord
 				if (Status == UserStatus.Offline)
 					_lastOnline = DateTime.UtcNow;
 			}
-
-			//Allows null
-			GameId = model.GameId;
+			
+			GameId = model.GameId; //Allows null
 		}
 		internal void Update(VoiceMemberInfo model)
 		{
@@ -188,7 +187,7 @@ namespace Discord
 			else
 				newRoles = new Dictionary<string, Role>();
 			Role everyone;
-			if (_serverId != null)
+			if (_server.Id != null)
 				everyone = Server.EveryoneRole;
 			else
 				everyone = _client.Roles.VirtualEveryone;