Refactor string interning to use enum and attribute

Replaces boolean UseStringInterning with StringInterningMode enum for more granular control (None, Attribute, All). Introduces AcStringInternAttribute for per-property interning configuration. Updates all usages and documentation to reflect the new approach, ensuring explicit and flexible string interning behavior in serialization. Default mode is now All to preserve legacy behavior.

AyCode.Benchmark/SerializationBenchmarks.cs

@@ -535,7 +535,7 @@ public abstract class AcBinaryOptionsBenchmarkBase
         BinaryBenchmarkMode.FastMode => new AcBinarySerializerOptions
         {
             UseMetadata = false,
-            UseStringInterning = false,
+            UseStringInterning = StringInterningMode.None,
             ReferenceHandling = ReferenceHandlingMode.None,
         },
         _ => new AcBinarySerializerOptions()

AyCode.Core.Serializers.Console/Program.cs

@@ -121,7 +121,7 @@ public static class Program
             sharedUser: sharedUser);
         
         var options = AcBinarySerializerOptions.WithoutReferenceHandling;
-        options.UseStringInterning = false;
+        options.UseStringInterning = StringInterningMode.None;
         
         // Warmup (fills caches)
         System.Console.WriteLine("Warming up (10 iterations)...");
@@ -419,7 +419,7 @@ public static class Program
             new AcBinaryBenchmark(testData.Order, AcBinarySerializerOptions.Default, SerializerAcBinaryDefault),
             new AcBinaryBenchmark(testData.Order, AcBinarySerializerOptions.WithoutReferenceHandling, SerializerAcBinaryNoRef),
             new AcBinaryBenchmark(testData.Order, AcBinarySerializerOptions.FastMode, SerializerAcBinaryFastMode),
-            new AcBinaryBenchmark(testData.Order, new AcBinarySerializerOptions { UseStringInterning = false }, SerializerAcBinaryNoIntern),
+            new AcBinaryBenchmark(testData.Order, new AcBinarySerializerOptions { UseStringInterning = StringInterningMode.None }, SerializerAcBinaryNoIntern),
             
             // AcJson
             new AcJsonBenchmark(testData.Order, AcJsonSerializerOptions.Default, SerializerAcJsonDefault),

AyCode.Core.Tests/Serialization/AcBinarySerializerBenchmarkTests.cs

@@ -62,7 +62,7 @@ public class AcBinarySerializerBenchmarkTests
         var order = TestDataFactory.CreateBenchmarkOrder(itemCount: 5, palletsPerItem: 3, measurementsPerPallet: 2, pointsPerMeasurement: 5);
 
         var binaryWithInterning = AcBinarySerializer.Serialize(order, AcBinarySerializerOptions.Default);
-        var binaryWithoutInterning = AcBinarySerializer.Serialize(order, new AcBinarySerializerOptions { UseStringInterning = false });
+        var binaryWithoutInterning = AcBinarySerializer.Serialize(order, new AcBinarySerializerOptions { UseStringInterning = StringInterningMode.None });
 
         // Note: String interning may not always result in smaller size due to header overhead
         // The primary benefit is for larger datasets with many repeated strings

AyCode.Core.Tests/Serialization/AcBinarySerializerStringInterningTests.cs

@@ -24,7 +24,7 @@ public class AcBinarySerializerStringInterningTests
 
         var binaryWithInterning = AcBinarySerializer.Serialize(obj, AcBinarySerializerOptions.Default);
         var binaryWithoutInterning = AcBinarySerializer.Serialize(obj,
-            new AcBinarySerializerOptions { UseStringInterning = false });
+            new AcBinarySerializerOptions { UseStringInterning = StringInterningMode.None });
 
         Assert.IsTrue(binaryWithInterning.Length < binaryWithoutInterning.Length,
             $"With interning: {binaryWithInterning.Length}, Without: {binaryWithoutInterning.Length}");

AyCode.Core.Tests/Serialization/QuickBenchmark.cs

@@ -197,7 +197,7 @@ public class QuickBenchmark
         var withInterningMs = sw.Elapsed.TotalMilliseconds;
 
         // Without interning
-        var noInternOptions = new AcBinarySerializerOptions { UseStringInterning = false };
+        var noInternOptions = new AcBinarySerializerOptions { UseStringInterning = StringInterningMode.None };
         sw.Restart();
         byte[] withoutInterning = null!;
         for (int i = 0; i < iterations; i++)
@@ -427,7 +427,7 @@ public class QuickBenchmark
             sharedMetadata: sharedMeta);
 
         var singleOptions = AcBinarySerializerOptions.FastMode;
-        singleOptions.UseStringInterning = false;
+        singleOptions.UseStringInterning = StringInterningMode.None;
 
         Console.WriteLine("=== MINIMAL WARMUP TEST ===");
         Console.WriteLine();
@@ -507,9 +507,9 @@ public class QuickBenchmark
 
         // Options
         var withRefOptions = AcBinarySerializerOptions.Default;
-        //withRefOptions.UseStringInterning = false;
+        //withRefOptions.UseStringInterning = StringInterningMode.None;
         var noRefOptions = AcBinarySerializerOptions.WithoutReferenceHandling;
-        noRefOptions.UseStringInterning = false;
+        noRefOptions.UseStringInterning = StringInterningMode.None;
 
         // Pre-serialize
         var acBinaryWithRef = AcBinarySerializer.Serialize(testOrder, withRefOptions);

AyCode.Core/Serializers/Binaries/AcBinarySerializer.BinarySerializationContext.cs

@@ -92,7 +92,7 @@ public static partial class AcBinarySerializer
 #endif
 
         // These properties delegate to Options for convenience
-        public bool UseStringInterning => Options.UseStringInterning;
+        public bool UseStringInterning => Options.UseStringInterning != StringInterningMode.None;
         public bool UseMetadata => Options.UseMetadata;
         public byte MinStringInternLength => Options.MinStringInternLength;
         public byte MaxStringInternLength => Options.MaxStringInternLength;

AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs

@@ -60,9 +60,9 @@ public static partial class AcBinarySerializer
         options ??= AcBinarySerializerOptions.Default;
         
         // For analysis, use the provided reference handling mode
-        var analysisOptions = new AcBinarySerializerOptions 
+        var analysisOptions = new AcBinarySerializerOptions
-        { 
+        {
-            UseStringInterning = true,
+            UseStringInterning = StringInterningMode.All,
             MinStringInternLength = options.MinStringInternLength,
             MaxStringInternLength = options.MaxStringInternLength,
             ReferenceHandling = options.ReferenceHandling

AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs

@@ -33,7 +33,7 @@ public sealed class AcBinarySerializerOptions : AcSerializerOptions
     /// </summary>
     public static AcBinarySerializerOptions FastMode => new()
     {
-        UseStringInterning = false,
+        UseStringInterning = StringInterningMode.None,
         ReferenceHandling = ReferenceHandlingMode.None
     };
 
@@ -44,7 +44,7 @@ public sealed class AcBinarySerializerOptions : AcSerializerOptions
     public static AcBinarySerializerOptions ShallowCopy => new()
     {
         MaxDepth = 0,
-        UseStringInterning = false,
+        UseStringInterning = StringInterningMode.None,
         ReferenceHandling = ReferenceHandlingMode.None
     };
 
@@ -89,12 +89,13 @@ public sealed class AcBinarySerializerOptions : AcSerializerOptions
     public bool UseMetadata { get; init; } = false;
 
     /// <summary>
-    /// Whether to intern repeated strings.
+    /// Controls how string interning is applied during serialization.
-    /// When enabled, duplicate strings are stored once and referenced by index.
+    /// None: No interning, all strings written inline.
-    /// Reduces size and memory for objects with many repeated string values.
+    /// Attribute: Only properties with [AcStringIntern(true)] are interned.
-    /// Default: true
+    /// All: All strings within length limits are interned (legacy behavior).
+    /// Default: All
     /// </summary>
-    public bool UseStringInterning { get; set; } = true;
+    public StringInterningMode UseStringInterning { get; set; } = StringInterningMode.All;
 
     /// <summary>
     /// Minimum string length to consider for interning.

AyCode.Core/Serializers/Binaries/AcStringInternAttribute.cs

@@ -0,0 +1,25 @@
+namespace AyCode.Core.Serializers.Binaries;
+
+/// <summary>
+/// Controls string interning for a specific property during binary serialization.
+/// When StringInterningMode is Attribute: only properties with [AcStringIntern(true)] are interned.
+/// When StringInterningMode is All: properties with [AcStringIntern(false)] opt-out from interning.
+/// Attribute is inherited from base class properties if not explicitly specified.
+/// </summary>
+[AttributeUsage(AttributeTargets.Property, Inherited = true, AllowMultiple = false)]
+public sealed class AcStringInternAttribute : Attribute
+{
+    /// <summary>
+    /// Whether string interning is enabled for this property.
+    /// </summary>
+    public bool Enabled { get; }
+
+    /// <summary>
+    /// Creates a new AcStringInternAttribute.
+    /// </summary>
+    /// <param name="enabled">True to enable interning, false to disable.</param>
+    public AcStringInternAttribute(bool enabled)
+    {
+        Enabled = enabled;
+    }
+}

AyCode.Core/Serializers/Binaries/StringInterningMode.cs

@@ -0,0 +1,24 @@
+namespace AyCode.Core.Serializers.Binaries;
+
+/// <summary>
+/// Controls string interning behavior during binary serialization.
+/// </summary>
+public enum StringInterningMode
+{
+    /// <summary>
+    /// No string interning. All strings are written inline.
+    /// </summary>
+    None = 0,
+
+    /// <summary>
+    /// Only intern strings on properties marked with [AcStringIntern(true)].
+    /// Properties without attribute or with [AcStringIntern(false)] are written inline.
+    /// </summary>
+    Attribute = 1,
+
+    /// <summary>
+    /// Intern all strings that meet the length criteria (MinStringInternLength to MaxStringInternLength).
+    /// [AcStringIntern(false)] can opt-out specific properties.
+    /// </summary>
+    All = 2
+}