From ed5e8d243f8ca55a30331bf613e75e5cd31d8919 Mon Sep 17 00:00:00 2001
From: Kamron Batman <3953314+kamronbatman@users.noreply.github.com>
Date: Sun, 19 Jul 2026 21:42:59 -0700
Subject: [PATCH] =?UTF-8?q?fix(advanced-search):=20D=20=E2=80=94=20correct?=
 =?UTF-8?q?=20@/|=20operator=20precedence=20(OR=20binds=20looser=20than=20?=
 =?UTF-8?q?AND)?=
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Extracts a pure, testable AdvancedSearchUtilities.EvaluateBoolean that
splits on the outermost '|' (OR) before '@' (AND), so `a@b|c` now
evaluates as `(a&&b)||c` instead of the previous `a&&(b||c)`.
AdvancedSearchThreadWorker.EvaluateRecursive delegates to it, supplying
the entity-aware leaf evaluator.
---
 .../AdvancedSearchUtilitiesTests.cs           | 15 ++++++++++++++
 .../AdvancedSearchThreadWorker.cs             | 20 ++-----------------
 .../AdvancedSearchUtilities.cs                | 18 +++++++++++++++++
 3 files changed, 35 insertions(+), 18 deletions(-)

diff --git a/Projects/UOContent.Tests/Tests/Engines/AdvancedSearch/AdvancedSearchUtilitiesTests.cs b/Projects/UOContent.Tests/Tests/Engines/AdvancedSearch/AdvancedSearchUtilitiesTests.cs
index 986e0d724..412e5c1e0 100644
--- a/Projects/UOContent.Tests/Tests/Engines/AdvancedSearch/AdvancedSearchUtilitiesTests.cs
+++ b/Projects/UOContent.Tests/Tests/Engines/AdvancedSearch/AdvancedSearchUtilitiesTests.cs
@@ -39,4 +39,19 @@ public class AdvancedSearchUtilitiesTests
     {
         Assert.True(AdvancedSearchUtilities.CompareValues(typeof(Layer), (byte)Layer.OneHanded, "onehanded", "="));
     }
+
+    [Theory]
+    // leaf value is "T"/"F"; evalLeaf returns leaf=="T"
+    [InlineData("T", true)]
+    [InlineData("F", false)]
+    [InlineData("F@F|T", true)]   // (F&&F)||T = T   (buggy code gave F&&(F||T)=F)
+    [InlineData("T|F@F", true)]   // T||(F&&F) = T   (buggy code gave (T||F)&&F=F)
+    [InlineData("T@F", false)]
+    [InlineData("T@T", true)]
+    [InlineData("F|F", false)]
+    public void EvaluateBoolean_Precedence(string expr, bool expected)
+    {
+        var result = AdvancedSearchUtilities.EvaluateBoolean(expr, leaf => leaf == "T");
+        Assert.Equal(expected, result);
+    }
 }
diff --git a/Projects/UOContent/Engines/Advanced Search/AdvancedSearchThreadWorker.cs b/Projects/UOContent/Engines/Advanced Search/AdvancedSearchThreadWorker.cs
index 57ec309f1..660df1058 100644
--- a/Projects/UOContent/Engines/Advanced Search/AdvancedSearchThreadWorker.cs	
+++ b/Projects/UOContent/Engines/Advanced Search/AdvancedSearchThreadWorker.cs	
@@ -317,24 +317,8 @@ public class AdvancedSearchThreadWorker
         }
     }
 
-    private static bool EvaluateRecursive(IEntity entity, ReadOnlySpan<char> span)
-    {
-        var atIndex = span.IndexOf('@');
-        var orIndex = span.IndexOf('|');
-
-        if (atIndex == -1 && orIndex == -1)
-        {
-            return EvaluateSingleExpression(entity, span);
-        }
-
-        var result = atIndex != -1;
-        var splitIndex = result ? atIndex : orIndex;
-
-        var left = EvaluateRecursive(entity, span.Slice(0, splitIndex));
-        var right = EvaluateRecursive(entity, span.Slice(splitIndex + 1));
-
-        return result ? left && right : left || right;
-    }
+    private static bool EvaluateRecursive(IEntity entity, ReadOnlySpan<char> span) =>
+        AdvancedSearchUtilities.EvaluateBoolean(span, leaf => EvaluateSingleExpression(entity, leaf));
 
     private static bool EvaluateSingleExpression(IEntity entity, ReadOnlySpan<char> expression)
     {
diff --git a/Projects/UOContent/Engines/Advanced Search/AdvancedSearchUtilities.cs b/Projects/UOContent/Engines/Advanced Search/AdvancedSearchUtilities.cs
index 9532fe20a..16355a249 100644
--- a/Projects/UOContent/Engines/Advanced Search/AdvancedSearchUtilities.cs	
+++ b/Projects/UOContent/Engines/Advanced Search/AdvancedSearchUtilities.cs	
@@ -360,6 +360,24 @@ public static class AdvancedSearchUtilities
         return false;
     }
 
+    // OR ('|') binds looser than AND ('@'); split on the outermost OR first, then AND.
+    internal static bool EvaluateBoolean(ReadOnlySpan<char> expr, Func<string, bool> evalLeaf)
+    {
+        var orIndex = expr.IndexOf('|');
+        if (orIndex != -1)
+        {
+            return EvaluateBoolean(expr[..orIndex], evalLeaf) || EvaluateBoolean(expr[(orIndex + 1)..], evalLeaf);
+        }
+
+        var andIndex = expr.IndexOf('@');
+        if (andIndex != -1)
+        {
+            return EvaluateBoolean(expr[..andIndex], evalLeaf) && EvaluateBoolean(expr[(andIndex + 1)..], evalLeaf);
+        }
+
+        return evalLeaf(expr.Trim().ToString());
+    }
+
     private static int GetEnumSize(Type enumType) =>
         Type.GetTypeCode(Enum.GetUnderlyingType(enumType)) switch
         {