Exclude known bots from earning coins while in chat

src/DevChatter.Bot.Core/ChatUserCollection.cs

@@ -5,37 +5,55 @@
 using DevChatter.Bot.Core.Data.Model;
 using DevChatter.Bot.Core.Data.Specifications;
 using DevChatter.Bot.Core.Extensions;
+using DevChatter.Bot.Core.Systems.Chat;
 
 namespace DevChatter.Bot.Core
 {
     public class ChatUserCollection : IChatUserCollection
     {
         private readonly IRepository _repository;
+        private readonly IKnownBotService _knownBotService;
         private readonly object _userCreationLock = new object();
 
         private readonly object _activeChatUsersLock = new object();
         private readonly List<string> _activeChatUsers = new List<string>();
 
-        public ChatUserCollection(IRepository repository)
+        public ChatUserCollection(IRepository repository, IKnownBotService knownBotService)
         {
             _repository = repository;
+            _knownBotService = knownBotService;
         }
 
-        public bool NeedToWatchUser(string displayName)
+        public bool NeedToWatchUser(string displayName, ChatUser chatUser)
         {
+            ChatUser chatUserFromDb = GetOrCreateChatUser(displayName, chatUser);
+
+            if (chatUserFromDb.IsKnownBot == null)
+            {
+                lock (_activeChatUsersLock)
+                {
+                    bool isKnownBot = _knownBotService.IsKnownBot(chatUserFromDb.DisplayName).GetAwaiter().GetResult();
+                    chatUserFromDb.IsKnownBot = isKnownBot;
+                    _repository.Update(chatUserFromDb);
+                }
+            }
+
+            if (chatUserFromDb.IsKnownBot.Value)
+                return false;
+
             // Don't lock in here
             // ReSharper disable once InconsistentlySynchronizedField
             return _activeChatUsers.All(activeDisplayName => activeDisplayName != displayName);
         }
 
 
-        public void WatchUser(string displayName)
+        public void WatchUser(string displayName, ChatUser chatUser)
         {
-            if (NeedToWatchUser(displayName))
+            if (NeedToWatchUser(displayName, chatUser))
             {
                 lock (_activeChatUsersLock)
                 {
-                    if (NeedToWatchUser(displayName))
+                    if (NeedToWatchUser(displayName, chatUser))
                     {
                         _activeChatUsers.Add(displayName);
                     }
@@ -74,7 +92,7 @@ public void StopWatching(string displayName)
         public bool UserHasAtLeast(string username, int tokensToRemove)
         {
             ChatUser chatUser = GetOrCreateChatUser(username);
-            WatchUser(chatUser.DisplayName);
+            WatchUser(chatUser.DisplayName, chatUser);
 
             return chatUser.Tokens >= tokensToRemove;
         }

src/DevChatter.Bot.Core/Data/Model/ChatUser.cs

@@ -8,6 +8,7 @@ public class ChatUser : DataEntity
         public string DisplayName { get; set; }
         public UserRole? Role { get; set; }
         public int Tokens { get; set; }
+        public bool? IsKnownBot { get; set; }
 
         public bool CanRunCommand(IBotCommand botCommand)
         {

src/DevChatter.Bot.Core/Events/CurrencyGenerator.cs

@@ -37,14 +37,13 @@ private void ChatClientOnOnUserNoticed(object sender, UserStatusEventArgs eventA
 
         private void WatchUserIfNeeded(string displayName, ChatUser chatUser)
         {
-            if (_chatUserCollection.NeedToWatchUser(displayName))
+            if (_chatUserCollection.NeedToWatchUser(displayName, chatUser))
             {
                 ChatUser userFromDb = _chatUserCollection.GetOrCreateChatUser(displayName, chatUser);
-                _chatUserCollection.WatchUser(userFromDb.DisplayName);
+                _chatUserCollection.WatchUser(userFromDb.DisplayName, userFromDb);
             }
         }
 
-
         private void ChatClientOnUserLeft(object sender, UserStatusEventArgs eventArgs)
         {
             _chatUserCollection.GetOrCreateChatUser(eventArgs.DisplayName, eventArgs.ToChatUser());

src/DevChatter.Bot.Core/IChatUserCollection.cs

@@ -7,12 +7,12 @@ namespace DevChatter.Bot.Core
     public interface IChatUserCollection
     {
         ChatUser GetOrCreateChatUser(string displayName, ChatUser chatUser = null);
-        bool NeedToWatchUser(string displayName);
+        bool NeedToWatchUser(string displayName, ChatUser chatUser);
         void StopWatching(string displayName);
         bool TryGiveCoins(string coinGiver, string coinReceiver, int coinsToGive);
         void UpdateEachChatter(Action<ChatUser> updateToApply);
         void UpdateSpecificChatters(Action<ChatUser> updateToApply, ISpecification<ChatUser> filter);
         bool UserHasAtLeast(string username, int tokensToRemove);
-        void WatchUser(string displayName);
+        void WatchUser(string displayName, ChatUser chatUser);
     }
 }

src/DevChatter.Bot.Core/Systems/Chat/IKnownBotService.cs

@@ -0,0 +1,9 @@
+using System.Threading.Tasks;
+
+namespace DevChatter.Bot.Core.Systems.Chat
+{
+    public interface IKnownBotService
+    {
+        Task<bool> IsKnownBot(string username);
+    }
+}

src/DevChatter.Bot.Infra.Ef/Migrations/20180513054353_Add-IsKnownBotColumn.cs

@@ -0,0 +1,22 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace DevChatter.Bot.Infra.Ef.Migrations
+{
+    public partial class AddIsKnownBotColumn : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<bool>(
+                name: "IsKnownBot",
+                table: "ChatUsers",
+                nullable: true);
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "IsKnownBot",
+                table: "ChatUsers");
+        }
+    }
+}

src/DevChatter.Bot.Infra.Ef/Migrations/AppDataContextModelSnapshot.cs

@@ -46,6 +46,8 @@ protected override void BuildModel(ModelBuilder modelBuilder)
 
                     b.Property<string>("DisplayName");
 
+                    b.Property<bool?>("IsKnownBot");
+
                     b.Property<int?>("Role");
 
                     b.Property<int>("Tokens");

src/DevChatter.Bot.Infra.Twitch/DevChatterBotTwitchModule.cs

@@ -23,6 +23,8 @@ protected override void Load(ContainerBuilder builder)
             builder.RegisterType<TwitchChatClient>().AsImplementedInterfaces().SingleInstance();
 
             builder.RegisterType<TwitchStreamingInfoService>().AsImplementedInterfaces().SingleInstance();
+
+            builder.RegisterType<TwitchKnownBotService>().AsImplementedInterfaces().SingleInstance();
         }
     }
 }

src/DevChatter.Bot.Infra.Twitch/TwitchKnownBotService.cs

@@ -0,0 +1,37 @@
+using System.Net;
+using System.Net.Http;
+using System.Threading.Tasks;
+using DevChatter.Bot.Core.Systems.Chat;
+
+namespace DevChatter.Bot.Infra.Twitch
+{
+    public class TwitchKnownBotService : IKnownBotService
+    {
+        private const string API_ENDPOINT = "https://api.twitchbots.info/v1/";
+
+        private readonly HttpClient _client;
+
+        public TwitchKnownBotService()
+        {
+            _client = new HttpClient();
+        }
+
+        public async Task<bool> IsKnownBot(string username)
+        {
+            HttpResponseMessage response = await _client.GetAsync($"{API_ENDPOINT}bot/{username}").ConfigureAwait(false);
+
+            switch (response.StatusCode)
+            {
+                case HttpStatusCode.NotFound:
+                    return false;
+
+                case HttpStatusCode.OK:
+                    return true;
+
+                default:
+                    throw new HttpRequestException(
+                        $"Unable to fetch known bot. Service returned {(int) response.StatusCode} {response.StatusCode}");
+            }
+        }
+    }
+}

src/UnitTests/Core/Automation/CurrencyUpdateTests/IsTimeToRunShould.cs

@@ -42,7 +42,9 @@ public void ReturnFalse_AfterInvokingAction()
             const int intervalInMinutes = 1;
             var repository = new Mock<IRepository>();
             repository.Setup(x => x.List(It.IsAny<ISpecification<ChatUser>>())).Returns(new List<ChatUser>());
-            var currencyGenerator = new CurrencyGenerator(new List<IChatClient>(), new ChatUserCollection(repository.Object));
+            var knownBotService = new Mock<IKnownBotService>();
+            var currencyGenerator = new CurrencyGenerator(new List<IChatClient>(),
+                new ChatUserCollection(repository.Object, knownBotService.Object));
             var fakeClock = new FakeClock();
             var currencyUpdate = new CurrencyUpdate(intervalInMinutes, currencyGenerator, fakeClock);