Refactored instruction decoder into smaller, more maintainable components using handler pattern

X86Disassembler/X86/Handlers/InstructionHandler.cs

@@ -0,0 +1,48 @@
+namespace X86Disassembler.X86.Handlers;
+
+/// <summary>
+/// Base class for all instruction handlers
+/// </summary>
+public abstract class InstructionHandler
+{
+    // Buffer containing the code to decode
+    protected readonly byte[] CodeBuffer;
+    
+    // The instruction decoder that owns this handler
+    protected readonly InstructionDecoder Decoder;
+    
+    // Length of the buffer
+    protected readonly int Length;
+    
+    // ModRM decoder for handling addressing modes
+    protected readonly ModRMDecoder ModRMDecoder;
+    
+    /// <summary>
+    /// Initializes a new instance of the InstructionHandler class
+    /// </summary>
+    /// <param name="codeBuffer">The buffer containing the code to decode</param>
+    /// <param name="decoder">The instruction decoder that owns this handler</param>
+    /// <param name="length">The length of the buffer</param>
+    protected InstructionHandler(byte[] codeBuffer, InstructionDecoder decoder, int length)
+    {
+        CodeBuffer = codeBuffer;
+        Decoder = decoder;
+        Length = length;
+        ModRMDecoder = new ModRMDecoder(codeBuffer, decoder, length);
+    }
+    
+    /// <summary>
+    /// Checks if this handler can decode the given opcode
+    /// </summary>
+    /// <param name="opcode">The opcode to check</param>
+    /// <returns>True if this handler can decode the opcode</returns>
+    public abstract bool CanHandle(byte opcode);
+    
+    /// <summary>
+    /// Decodes an instruction
+    /// </summary>
+    /// <param name="opcode">The opcode of the instruction</param>
+    /// <param name="instruction">The instruction object to populate</param>
+    /// <returns>True if the instruction was successfully decoded</returns>
+    public abstract bool Decode(byte opcode, Instruction instruction);
+}