Implement menu file parsing

source/app.d

@@ -1,4 +1,6 @@
 import std.stdio;
+import std.range;
+import std.algorithm;
 
 import cm3d2;
 
@@ -18,7 +20,9 @@ void main(string[] args)
 			help(args[0]);
 			break;
 		case "menu-to-sdl":
-        	throw new Exception("Not implemented yet");
+			ubyte[] data = stdin.byChunk(4096).joiner.array;
+			writeln(Menu.fromMenu(data).toSDL());
+			break;
 		case "sdl-to-menu":
         	throw new Exception("Not implemented yet");
 		default:

source/cm3d2/menu.d

@@ -1,15 +1,96 @@
 module cm3d2.menu;
 
+import std.bitmanip;
+import std.conv;
+import std.math;
+
 class Menu
 {
+    uint fileVersion;
+    string path;
+
+    string name;
+    string category;
+    string description;
+
+    string[][] lines;
+
     public static Menu fromSDL(string sdl)
     {
         throw new Exception("Not implemented yet");
     }
 
-    public static Menu fromMenu(string menu)
+    public static Menu fromMenu(ubyte[] data)
     {
-        throw new Exception("Not implemented yet");
+        auto menu = new Menu();
+
+		ubyte readByte()
+		{
+			auto value = data[0];
+			data = data[1 .. $];
+			return value;
+		}
+
+		string readString()
+		{
+            auto length = 0;
+            ubyte[] chars;
+
+            while (true)
+            {
+                auto lengthByte = readByte();
+
+                if (length != 0 && lengthByte < 128)
+                {
+                    break;
+                }
+
+                length = length << 8 | lengthByte;
+
+                if (lengthByte < 128)
+                {
+                    break;
+                }
+            }
+
+			auto value = cast(string) data[0 .. length];
+			data = data[length .. $];
+
+			return value;
+		}
+
+        uint readInt()
+        {
+            auto value = littleEndianToNative!uint(data[0 .. 4]);
+            data = data[4 .. $];
+            return value;
+        }
+
+        assert(readString() == "CM3D2_MENU", "Not a valid .menu file");
+
+		menu.fileVersion = readInt();
+        menu.path = readString();
+        menu.name = readString();
+        menu.category = readString();
+        menu.description = readString();
+
+        assert(readInt() == data.length, "Unexpected data at end of file");
+
+        while(data.length > 0)
+        {
+            string[] line;
+
+            foreach (_; 0 .. readByte())
+            {
+                line ~= readString();
+            }
+
+            menu.lines ~= line;
+        }
+
+        std.stdio.writeln(menu.lines);
+
+        return menu;
     }
 
     public string toMenu()