Added FilterList

Several upcoming features will be making use of the same whitelist
and blacklist filtering concept that RegexResponder currently uses.

ConfigItem/EntityList.cs

@@ -7,8 +7,6 @@ using System.Linq;
 
 namespace Noikoio.RegexBot.ConfigItem
 {
-    enum FilterType { None, Whitelist, Blacklist }
-
     /// <summary>
     /// Represents a structure in bot configuration that contains a list of
     /// channels, roles, and users.
@@ -70,7 +68,7 @@ namespace Noikoio.RegexBot.ConfigItem
         /// </summary>
         /// <param name="msg">An incoming message.</param>
         /// <returns>
-        /// True if the <see cref="SocketMessage"/> occurred within a channel specified in this list,
+        /// True if '<paramref name="msg"/>' occurred within a channel specified in this list,
         /// or if the message author belongs to one or more roles in this list, or if the user itself
         /// is defined within this list.
         /// </returns>
@@ -125,28 +123,5 @@ namespace Noikoio.RegexBot.ConfigItem
             // No match.
             return false;
         }
-
-        /// <summary>
-        /// Helper method for reading whitelist and blacklist filtering lists.
-        /// </summary>
-        /// <param name="section">
-        /// A JSON object which presumably contains an array named "whitelist" or "blacklist".
-        /// </param>
-        public static (FilterType, EntityList) GetFilterList(JObject section)
-        {
-            var mode = FilterType.None;
-            EntityList list;
-            if (section["whitelist"] != null) mode = FilterType.Whitelist;
-            if (section["blacklist"] != null)
-            {
-                if (mode == FilterType.Whitelist)
-                    throw new RuleImportException("Cannot have whitelist AND blacklist defined.");
-                mode = FilterType.Blacklist;
-            }
-            if (mode == FilterType.None) list = new EntityList(); // might even be fine to keep it null?
-            else list = new EntityList(section[mode == FilterType.Whitelist ? "whitelist" : "blacklist"]);
-
-            return (mode, list);
-        }
     }
 }

ConfigItem/FilterList.cs

@@ -0,0 +1,91 @@
+using Discord.WebSocket;
+using Newtonsoft.Json.Linq;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Noikoio.RegexBot.ConfigItem
+{
+    enum FilterType { None, Whitelist, Blacklist }
+
+    /// <summary>
+    /// Represents whitelist/blacklist configuration, including exemptions.
+    /// </summary>
+    struct FilterList
+    {
+        FilterType _type;
+        EntityList _filterList;
+        EntityList _exemptions;
+
+        public FilterType FilterMode => _type;
+        public EntityList FilterEntities => _filterList;
+        public EntityList FilterExemptions => _exemptions;
+
+        /// <summary>
+        /// Gets the 
+        /// </summary>
+        /// <param name="conf">
+        /// A JSON object which presumably contains an array named "whitelist" or "blacklist",
+        /// and optionally one named "exempt".
+        /// </param>
+        /// <exception cref="RuleImportException">
+        /// Thrown if both "whitelist" and "blacklist" definitions were found, if
+        /// "exempt" was found without a corresponding "whitelist" or "blacklist",
+        /// or if there was an issue parsing an EntityList within these definitions.
+        /// </exception>
+        public FilterList(JObject conf)
+        {
+            _type = FilterType.None;
+
+            if (conf["whitelist"] != null) _type = FilterType.Whitelist;
+            if (conf["blacklist"] != null)
+            {
+                if (_type != FilterType.None)
+                    throw new RuleImportException("Cannot have both 'whitelist' and 'blacklist' values defined.");
+                _type = FilterType.Blacklist;
+            }
+            if (_type == FilterType.None)
+            {
+                _filterList = null;
+                _exemptions = null;
+                if (conf["exempt"] != null)
+                    throw new RuleImportException("Cannot have 'exempt' defined if no corresponding " +
+                        "'whitelist' or 'blacklist' has been defined in the same section.");
+            }
+            else
+            {
+                _filterList = new EntityList(conf[_type == FilterType.Whitelist ? "whitelist" : "blacklist"]);
+                _exemptions = new EntityList(conf["exempt"]); // EntityList constructor checks for null value
+            }
+        }
+
+        /// <summary>
+        /// Determines if the parameters of '<paramref name="msg"/>' are a match with filtering
+        /// rules defined in this instance.
+        /// </summary>
+        /// <param name="msg">An incoming message.</param>
+        /// <returns>
+        /// True if the user or channel specified by '<paramref name="msg"/>' is filtered by
+        /// the configuration defined in this instance.
+        /// </returns>
+        public bool IsFiltered(SocketMessage msg)
+        {
+            if (FilterMode == FilterType.None) return false;
+
+            bool inFilter = FilterEntities.ExistsInList(msg);
+
+            if (FilterMode == FilterType.Whitelist)
+            {
+                if (!inFilter) return true;
+                return FilterExemptions.ExistsInList(msg);
+            }
+            else if (FilterMode == FilterType.Blacklist)
+            {
+                if (!inFilter) return false;
+                return !FilterExemptions.ExistsInList(msg);
+            }
+
+            throw new Exception("this shouldn't happen");
+        }
+    }
+}

Feature/RegexResponder/EventProcessor.cs

@@ -128,7 +128,7 @@ namespace Noikoio.RegexBot.Feature.RegexResponder
             // Moderator bypass check
             if (rule.AllowModBypass == true && srv.Moderators.ExistsInList(msg)) return;
             // Individual rule filtering check
-            if (IsFiltered(rule, msg)) return;
+            if (rule.Filter.IsFiltered(msg)) return;
 
             // And finally, pattern matching checks
             bool success = false;
@@ -221,26 +221,6 @@ namespace Noikoio.RegexBot.Feature.RegexResponder
             return result.ToString();
         }
 
-        private bool IsFiltered(RuleConfig r, SocketMessage m)
-        {
-            if (r.FilterMode == FilterType.None) return false;
-
-            bool inFilter = r.FilterList.ExistsInList(m);
-            
-            if (r.FilterMode == FilterType.Whitelist)
-            {
-                if (!inFilter) return true;
-                return r.FilterExemptions.ExistsInList(m);
-            }
-            else if (r.FilterMode == FilterType.Blacklist)
-            {
-                if (!inFilter) return false;
-                return !r.FilterExemptions.ExistsInList(m);
-            }
-
-            return false; // this shouldn't happen™
-        }
-
         private string[] SplitParams(string cmd, int? limit = null)
         {
             if (limit.HasValue)

Feature/RegexResponder/RuleConfig.cs

@@ -15,9 +15,7 @@ namespace Noikoio.RegexBot.Feature.RegexResponder
         private string _displayName;
         private IEnumerable<Regex> _regex;
         private IEnumerable<string> _responses;
-        private FilterType _filtermode;
+        private FilterList _filter;
-        private EntityList _filterlist;
-        private EntityList _filterexempt;
         private int? _minLength;
         private int? _maxLength;
         private bool _modBypass;
@@ -26,9 +24,7 @@ namespace Noikoio.RegexBot.Feature.RegexResponder
         public string DisplayName => _displayName;
         public IEnumerable<Regex> Regex => _regex;
         public IEnumerable<string> Responses => _responses;
-        public FilterType FilterMode => _filtermode;
+        public FilterList Filter => _filter;
-        public EntityList FilterList => _filterlist;
-        public EntityList FilterExemptions => _filterexempt;
         public int? MinLength => _minLength;
         public int? MaxLength => _maxLength;
         public bool AllowModBypass => _modBypass;
@@ -131,9 +127,7 @@ namespace Noikoio.RegexBot.Feature.RegexResponder
             _responses = responses.ToArray();
 
             // (white|black)list filtering
-            (_filtermode, _filterlist) = EntityList.GetFilterList(ruleconf);
+            _filter = new FilterList(ruleconf);
-            // filtering exemptions
-            _filterexempt = new EntityList(ruleconf["exempt"]);
 
             // moderator bypass toggle - true by default, must be explicitly set to false
             bool? modoverride = ruleconf["AllowModBypass"]?.Value<bool>();