From 62ab1605722df915a6b69b9c197712a80b7b72dd Mon Sep 17 00:00:00 2001
From: Argo Zhang <argo@live.ca>
Date: Thu, 20 Nov 2025 17:30:57 +0800
Subject: [PATCH] =?UTF-8?q?refactor:=20=E7=B2=BE=E7=AE=80=E4=BB=A3?=
 =?UTF-8?q?=E7=A0=81?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../Abstractions/AbstractCacheStrategy.cs     | 16 +++----------
 .../Internal/CacheStrategyFactory.cs          | 23 +++++--------------
 .../Internal/ContentCacheStrategy.cs          |  6 -----
 .../Internal/FileCacheStrategy.cs             | 11 +--------
 .../Internal/VectorIndexCacheStrategy.cs      |  6 -----
 5 files changed, 10 insertions(+), 52 deletions(-)

diff --git a/binding/csharp/IP2Region.Net/Internal/Abstractions/AbstractCacheStrategy.cs b/binding/csharp/IP2Region.Net/Internal/Abstractions/AbstractCacheStrategy.cs
index 13d19e5..8d5f06c 100644
--- a/binding/csharp/IP2Region.Net/Internal/Abstractions/AbstractCacheStrategy.cs
+++ b/binding/csharp/IP2Region.Net/Internal/Abstractions/AbstractCacheStrategy.cs
@@ -26,16 +26,6 @@ internal abstract class AbstractCacheStrategy
             useAsync: true);
     }
 
-    protected int GetVectorIndexStartPos(uint ip)
-    {
-        var il0 = ip >> 24 & 0xFF;
-        var il1 = ip >> 16 & 0xFF;
-        var idx = il0 * VectorIndexCols * VectorIndexSize + il1 * VectorIndexSize;
-        return (int)idx;
-    }
-
-    internal abstract ReadOnlyMemory<byte> GetVectorIndex(uint ip);
-
     internal virtual ReadOnlyMemory<byte> GetData(int offset, int length)
     {
         byte[] buffer = ArrayPool<byte>.Shared.Rent(length);
@@ -45,14 +35,14 @@ internal abstract class AbstractCacheStrategy
             XdbFileStream.Seek(offset, SeekOrigin.Begin);
 
             int bytesRead;
-            do
+            while (totalBytesRead < length)
             {
                 int bytesToRead = Math.Min(BufferSize, length - totalBytesRead);
                 bytesRead = XdbFileStream.Read(buffer, totalBytesRead, bytesToRead);
                 totalBytesRead += bytesRead;
-            
+
                 IoCount++;
-            } while (bytesRead > 0 && totalBytesRead < length);
+            }
         }
         finally
         {
diff --git a/binding/csharp/IP2Region.Net/Internal/CacheStrategyFactory.cs b/binding/csharp/IP2Region.Net/Internal/CacheStrategyFactory.cs
index 14e8eb0..4d9b3d5 100644
--- a/binding/csharp/IP2Region.Net/Internal/CacheStrategyFactory.cs
+++ b/binding/csharp/IP2Region.Net/Internal/CacheStrategyFactory.cs
@@ -9,23 +9,12 @@ using IP2Region.Net.XDB;
 
 namespace IP2Region.Net.Internal;
 
-internal class CacheStrategyFactory
+internal class CacheStrategyFactory(string xdbPath)
 {
-    private readonly string _xdbPath;
-
-    public CacheStrategyFactory(string xdbPath)
+    public AbstractCacheStrategy CreateCacheStrategy(CachePolicy cachePolicy) => cachePolicy switch
     {
-        _xdbPath = xdbPath;
-    }
-
-    public AbstractCacheStrategy CreateCacheStrategy(CachePolicy cachePolicy)
-    {
-        return cachePolicy switch
-        {
-            CachePolicy.Content => new ContentCacheStrategy(_xdbPath),
-            CachePolicy.VectorIndex => new VectorIndexCacheStrategy(_xdbPath),
-            CachePolicy.File => new FileCacheStrategy(_xdbPath),
-            _ => throw new ArgumentException(nameof(cachePolicy))
-        };
-    }
+        CachePolicy.Content => new ContentCacheStrategy(xdbPath),
+        CachePolicy.VectorIndex => new VectorIndexCacheStrategy(xdbPath),
+        _ => new FileCacheStrategy(xdbPath),
+    };
 }
\ No newline at end of file
diff --git a/binding/csharp/IP2Region.Net/Internal/ContentCacheStrategy.cs b/binding/csharp/IP2Region.Net/Internal/ContentCacheStrategy.cs
index e3094e1..614495a 100644
--- a/binding/csharp/IP2Region.Net/Internal/ContentCacheStrategy.cs
+++ b/binding/csharp/IP2Region.Net/Internal/ContentCacheStrategy.cs
@@ -19,12 +19,6 @@ internal class ContentCacheStrategy : AbstractCacheStrategy
         XdbFileStream.Dispose();
     }
 
-    internal override ReadOnlyMemory<byte> GetVectorIndex(uint ip)
-    {
-        int idx = GetVectorIndexStartPos(ip);
-        return _cacheData.Slice(HeaderInfoLength + idx, VectorIndexSize);
-    }
-
     internal override ReadOnlyMemory<byte> GetData(int offset, int length)
     {
         return _cacheData.Slice(offset, length);
diff --git a/binding/csharp/IP2Region.Net/Internal/FileCacheStrategy.cs b/binding/csharp/IP2Region.Net/Internal/FileCacheStrategy.cs
index 31f90f3..0f98cfe 100644
--- a/binding/csharp/IP2Region.Net/Internal/FileCacheStrategy.cs
+++ b/binding/csharp/IP2Region.Net/Internal/FileCacheStrategy.cs
@@ -8,15 +8,6 @@ using IP2Region.Net.Internal.Abstractions;
 
 namespace IP2Region.Net.Internal;
 
-internal class FileCacheStrategy : AbstractCacheStrategy
+internal class FileCacheStrategy(string xdbPath) : AbstractCacheStrategy(xdbPath)
 {
-    public FileCacheStrategy(string xdbPath) : base(xdbPath)
-    {
-    }
-
-    internal override ReadOnlyMemory<byte> GetVectorIndex(uint ip)
-    {
-        var idx = GetVectorIndexStartPos(ip);
-        return GetData(HeaderInfoLength + idx, VectorIndexSize);
-    }
 }
\ No newline at end of file
diff --git a/binding/csharp/IP2Region.Net/Internal/VectorIndexCacheStrategy.cs b/binding/csharp/IP2Region.Net/Internal/VectorIndexCacheStrategy.cs
index f1d8ae6..e9f5fac 100644
--- a/binding/csharp/IP2Region.Net/Internal/VectorIndexCacheStrategy.cs
+++ b/binding/csharp/IP2Region.Net/Internal/VectorIndexCacheStrategy.cs
@@ -17,10 +17,4 @@ internal class VectorIndexCacheStrategy : AbstractCacheStrategy
         var vectorLength = VectorIndexRows * VectorIndexCols * VectorIndexSize;
         _vectorIndex = base.GetData(HeaderInfoLength, vectorLength);
     }
-
-    internal override ReadOnlyMemory<byte> GetVectorIndex(uint ip)
-    {
-        var idx = GetVectorIndexStartPos(ip);
-        return _vectorIndex.Slice(idx, VectorIndexSize);
-    }
 }
\ No newline at end of file