Merge pull request #369 from Unity-Developer-Community/hariedo-patch-1

Preliminary support for fuzz strings and groundwork for fuzz tables, starting with a test in the Miku topic detector for Reenaki.

Author: hariedo

DiscordBot/Data/FuzzTable.cs

@@ -0,0 +1,63 @@
+// FuzzTable.cs
+//
+using System;
+using System.Text.RegularExpressions;
+
+namespace DiscordBot.Data;
+
+public class FuzzTable
+{
+    private static Random random = new();
+    private static Regex parenContents = null;
+    private static TimeSpan timeout = new(10*10000/*x10nanoseconds*/);
+
+    //TODO: an instance keeps an array of alternates and an MRU list
+
+    // Evaluate a single fuzz string.
+    //   "(He|She|They) (picked|selected) a (green|red|blue) (ball|block)."
+    //   "She picked a red ball."
+    // Replace any parenthetical phrase with one of its choices at random.
+    // Allows for nesting of choices.  There's currently no way to escape
+    // parentheses or vertical bars so strings must not include strays.
+    // Returns one permutation from all choice alternatives given.
+    // Does not remember what choices were given.
+    //
+    public static string Evaluate(string fuzz)
+    {
+        if (string.IsNullOrEmpty(fuzz))
+            return "";
+		if (parenContents == null)
+			parenContents =
+				new(@"\( ( [^(]*? ) \)",
+					RegexOptions.IgnorePatternWhitespace |
+					RegexOptions.Compiled,
+					timeout);
+		string before = null;
+		while (fuzz != before)
+		{
+			before = fuzz;
+            try
+            {
+    			fuzz = parenContents.Replace(fuzz,
+    				(m) => PickAlternate(m.Groups[1].ToString()));
+            }
+            catch (RegexMatchTimeoutException)
+            {
+                break;
+            }
+		}
+		return fuzz;
+    }
+
+    private static string PickAlternate(string fuzz)
+    {
+        if (string.IsNullOrEmpty(fuzz))
+            return "";
+        string[] alternates = fuzz.Split('|');
+        if (alternates == null || alternates.Length == 0)
+            return "";
+        int pick = random.Next(0, alternates.Length);
+        return alternates[pick];
+    }
+
+}

DiscordBot/Services/UserService.cs

@@ -7,6 +7,7 @@
 using DiscordBot.Domain;
 using DiscordBot.Settings;
 using DiscordBot.Skin;
+using DiscordBot.Data;
 using ImageMagick;
 using Newtonsoft.Json;
 
@@ -115,11 +116,14 @@ Init thanks
         Init Miku
         Gag feature has no external settings, hardcoded userid refers to Reenaki/Kiki.
         */
-        _mikuMentioned = DateTime.Now;
         _mikuCooldownTime = new TimeSpan(0, 39, 0); // 39min
         //_mikuCooldownTime = new TimeSpan(0, 0, 39); // test 39sec
+        _mikuMentioned = DateTime.Now - _mikuCooldownTime;
         _mikuRegex = @"(?i)\b(miku|hatsune|初音ミク|初音|ミク)\b";
-        _mikuReply = ":three: :nine: Oi, mite, mite, <@358915848515354626> -chan!";
+        _mikuReply =
+            "(:three: :nine:|:microphone:|:notes:|:musical_note:|:musical_keyboard:|:mirror_ball:) " +
+            "(Oi, mite, mite,|Heya,|Hey, look,|Did someone mention Miku?) " +
+            "<@358915848515354626> (-chan|)!";
         //_mikuReply = "Oi, mite, mite, <@427306565184389132> ! :three: :nine:"; // test
 
         /*
@@ -541,7 +545,8 @@ public async Task MikuCheck(SocketMessage messageParam)
             return;
 
         _mikuMentioned = now;
-        await messageParam.Channel.SendMessageAsync(_mikuReply);
+        var reply = FuzzTable.Evaluate(_mikuReply);
+        await messageParam.Channel.SendMessageAsync(reply);
     }
 
     public async Task CodeCheck(SocketMessage messageParam)