Nezhna spam

src/Nullinside.Api.TwitchBot.Tests/ChatRules/NezhnaTests.cs

@@ -0,0 +1,27 @@
+using Moq;
+
+using Nullinside.Api.Common.Twitch;
+using Nullinside.Api.TwitchBot.ChatRules;
+
+namespace Nullinside.Api.TwitchBot.Tests.ChatRules;
+
+/// <summary>
+///   Tests the <see cref="StreamViewers" /> class.
+/// </summary>
+public class NezhnaTests : AChatRuleUnitTestBase<Nezhna> {
+  /// <summary>
+  ///   Tests the strings typed in chats.
+  /// </summary>
+  /// <param name="badString">The string that should fail.</param>
+  [Test]
+  [TestCase("Visit nezhna dot com com to boost your viewers and climb the Twitch rankings. Join thousands of successful streamers now!  @7xgkq3EK")]
+  public async Task TestKnownStrings(string badString) {
+    var rule = new Nezhna();
+    var botProxy = new Mock<ITwitchApiProxy>();
+    var chat = new TwitchChatMessage(true, badString, "123", "456");
+
+    // Process the message and assert that we fail the message.
+    bool result = await rule.Handle("123", botProxy.Object, chat, _db);
+    Assert.That(result, Is.False);
+  }
+}

src/Nullinside.Api.TwitchBot/ChatRules/Nezhna.cs

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+using Nullinside.Api.Common.Twitch;
+using Nullinside.Api.Model;
+using Nullinside.Api.Model.Ddl;
+
+using TwitchLib.Client.Models;
+
+namespace Nullinside.Api.TwitchBot.ChatRules;
+
+/// <summary>
+///   Handles the "nezhna dot com" bots.
+/// </summary>
+public class Nezhna : AChatRule {
+  private const string SPAM = "Visit nezhna dot com com to boost your viewers and climb the Twitch rankings. Join thousands of successful streamers now!";
+
+  /// <inheritdoc />
+  public override bool ShouldRun(TwitchUserConfig config) {
+    return config is { Enabled: true, BanKnownBots: true };
+  }
+
+  /// <inheritdoc />
+  public override async Task<bool> Handle(string channelId, ITwitchApiProxy botProxy, TwitchChatMessage message,
+    INullinsideContext db, CancellationToken stoppingToken = new()) {
+    if (!message.IsFirstMessage) {
+      return true;
+    }
+
+    // The number of spaces per message may chance, so normalize that and lowercase it for comparison.
+    string normalized = string.Join(' ', message.Message.Split(" ").Where(s => !string.IsNullOrWhiteSpace(s)))
+      .ToLowerInvariant();
+
+    if (normalized.StartsWith(SPAM, StringComparison.InvariantCultureIgnoreCase)) {
+      await BanAndLog(channelId, botProxy, new[] { (message.UserId, message.Username) },
+        "[Bot] Spam (Nezhna)", db, stoppingToken);
+      return false;
+    }
+
+    return true;
+  }
+}