WIP implementing TZX support

Core/Io/TzxParser.cs

@@ -0,0 +1,56 @@
+using Core.Io;
+using System;
+using System.Collections.Generic;
+using System.IO;
+
+namespace Core.Io
+{
+    public class TzxParser
+    {
+        public static List<TzxBlock> Parse(byte[] fileBytes)
+        {
+            List<TzxBlock> blocks = new List<TzxBlock>();
+
+            using (MemoryStream ms = new MemoryStream(fileBytes))
+            using (BinaryReader br = new BinaryReader(ms))
+            {
+                // 1. Verify the 10-Byte Header
+                // Signature is "ZXTape!" followed by EOF (0x1A)
+                byte[] signature = br.ReadBytes(8);
+                string sigString = System.Text.Encoding.ASCII.GetString(signature);
+
+                if (sigString != "ZXTape!\x1A")
+                    throw new Exception("Invalid TZX Signature! Is this a real TZX file?");
+
+                byte majorVersion = br.ReadByte();
+                byte minorVersion = br.ReadByte();
+
+                // 2. Read the blocks until we hit the end of the file
+                while (ms.Position < ms.Length)
+                {
+                    byte blockId = br.ReadByte();
+
+                    switch (blockId)
+                    {
+                        case 0x10: // Standard Speed Data
+                            var stdBlock = new StandardSpeedBlock
+                            {
+                                PauseAfterMs = br.ReadUInt16(),
+                                DataLength = br.ReadUInt16()
+                            };
+                            stdBlock.Data = br.ReadBytes(stdBlock.DataLength);
+                            blocks.Add(stdBlock);
+                            break;
+
+                        // TODO: Add cases for 0x11 (Turbo), 0x12 (Tone), 0x13 (Pulses), etc.
+
+                        default:
+                            throw new NotImplementedException($"TZX Block ID 0x{blockId:X2} is not supported yet!");
+                    }
+                }
+            }
+
+            return blocks;
+        }
+    }
+}