Make FilterRunner more accurate

SabreTools.Filter/FilterRunner.cs

@@ -45,14 +45,13 @@ namespace SabreTools.Filter
             {
                 Header => MetadataFile.HeaderKey,
                 Machine => MetadataFile.MachineKey,
-                DatItem => dictionaryBase.ReadString(DatItem.TypeKey),
+                DatItem => TypeHelper.GetXmlRootAttributeElementName(dictionaryBase.GetType()),
                 _ => null,
             };
 
             // Loop through and run each filter in order
             foreach (var filter in this.Filters)
             {
-                // TODO: Make this step more accurate
                 // If the filter isn't for this object type, skip
                 if (filter.Key[0] != itemName)
                     continue;

SabreTools.Filter/TypeHelper.cs

@@ -40,7 +40,18 @@ namespace SabreTools.Filter
             return AppDomain.CurrentDomain.GetAssemblies()
                 .SelectMany(a => a.GetTypes())
                 .Where(t => t.IsAssignableFrom(typeof(DatItem)) && t.IsClass)
-                .FirstOrDefault(t => t.GetCustomAttribute<XmlRootAttribute>()?.ElementName == itemType);
+                .FirstOrDefault(t => GetXmlRootAttributeElementName(t) == itemType);
+        }
+
+        /// <summary>
+        /// Attempt to get the XmlRootAttribute.ElementName value from a type
+        /// </summary>
+        public static string? GetXmlRootAttributeElementName(Type? type)
+        {
+            if (type == null)
+                return null;
+
+            return type.GetCustomAttribute<XmlRootAttribute>()?.ElementName;
         }
     }
 }

SabreTools.Models/Internal/ItemType.cs

@@ -3,7 +3,6 @@ namespace SabreTools.Models.Internal
     /// <summary>
     /// Determine what type of file an item is
     /// </summary>
-    /// <remarks>TODO: Create attribute for internal names</remarks>
     public enum ItemType
     {
         /// <summary>