Feature: CustomStatusGame Activity (#1406)

* Implement CustomStatusGame activity

Adds the CustomStatusGame class, which is the activity corresponding to the custom status feature.

* Remove unused import from Game.cs

src/Discord.Net.Core/Entities/Activities/ActivityType.cs

@@ -20,6 +20,10 @@ namespace Discord
         /// <summary>
         ///     The user is watching some form of media.
         /// </summary>
-        Watching = 3
+        Watching = 3,
+        /// <summary>
+        ///     The user has set a custom status.
+        /// </summary>
+        CustomStatus = 4,
     }
 }

src/Discord.Net.Core/Entities/Activities/CustomStatusGame.cs

@@ -0,0 +1,40 @@
+using System;
+using System.Diagnostics;
+
+namespace Discord
+{
+    /// <summary>
+    ///     A user's activity for their custom status.
+    /// </summary>
+    [DebuggerDisplay(@"{DebuggerDisplay,nq}")]
+    public class CustomStatusGame : Game
+    {
+        internal CustomStatusGame() { }
+
+        /// <summary>
+        ///     Gets the emote, if it is set.
+        /// </summary>
+        /// <returns>
+        ///     An <see cref="IEmote"/> containing the <see cref="Emoji"/> or <see cref="GuildEmote"/> set by the user.
+        /// </returns>
+        public IEmote Emote { get; internal set; }
+
+        /// <summary>
+        ///     Gets the timestamp of when this status was created.
+        /// </summary>
+        /// <returns>
+        ///     A <see cref="DateTimeOffset"/> containing the time when this status was created.
+        /// </returns>
+        public DateTimeOffset CreatedAt { get; internal set; }
+
+        /// <summary>
+        ///     Gets the state of the status.
+        /// </summary>
+        public string State { get; internal set; }
+
+        public override string ToString()
+            => $"{Emote} {State}";
+
+        private string DebuggerDisplay => $"{Name}";
+    }
+}

src/Discord.Net.Rest/API/Common/Game.cs

@@ -35,6 +35,12 @@ namespace Discord.API
         public Optional<string> SessionId { get; set; }
         [JsonProperty("Flags")]
         public Optional<ActivityProperties> Flags { get; set; }
+        [JsonProperty("id")]
+        public Optional<string> Id { get; set; }
+        [JsonProperty("emoji")]
+        public Optional<Emoji> Emoji { get; set; }
+        [JsonProperty("created_at")]
+        public Optional<long> CreatedAt { get; set; }
 
         [OnError]
         internal void OnError(StreamingContext context, ErrorContext errorContext)

src/Discord.Net.Rest/Extensions/EntityExtensions.cs

@@ -5,6 +5,13 @@ namespace Discord.Rest
 {
     internal static class EntityExtensions
     {
+        public static IEmote ToIEmote(this API.Emoji model)
+        {
+            if (model.Id.HasValue)
+                return model.ToEntity();
+            return new Emoji(model.Name);
+        }
+
         public static GuildEmote ToEntity(this API.Emoji model)
             => new GuildEmote(model.Id.Value,
                 model.Name,

src/Discord.Net.WebSocket/Extensions/EntityExtensions.cs

@@ -1,3 +1,5 @@
+using Discord.Rest;
+using System;
 using System.Collections.Immutable;
 using System.Linq;
 
@@ -7,6 +9,19 @@ namespace Discord.WebSocket
     {
         public static IActivity ToEntity(this API.Game model)
         {
+            // Custom Status Game
+            if (model.Id.IsSpecified)
+            {
+                return new CustomStatusGame()
+                {
+                    Type = ActivityType.CustomStatus,
+                    Name = model.Name,
+                    State = model.State.IsSpecified ? model.State.Value : null,
+                    Emote = model.Emoji.IsSpecified ? model.Emoji.Value.ToIEmote() : null,
+                    CreatedAt = DateTimeOffset.FromUnixTimeMilliseconds(model.CreatedAt.Value),
+                };
+            }
+
             // Spotify Game
             if (model.SyncId.IsSpecified)
             {