gaming: Add melonDS

modules/programs/gaming/default.nix

@@ -7,16 +7,15 @@ in {
     enable = lib.mkEnableOption "Configure gaming options";
   };
   config = lib.mkIf cfg.enable {
-    nixpkgs.config.retroarch = {
-      enableDesmume = true;
-      enableMGBA = true;
-      enableDolphin = true;
-    };
-
     environment.systemPackages = with pkgs; [
       winePackages.stagingFull winetricks lutris-free-wrapped
 
-      retroarch
+      (pkgs.callPackage ./wrapper.nix {
+        inherit (pkgs) retroarch;
+        cores = with pkgs.libretro; [
+          mgba mupen64plus melonds desmume dolphin
+        ];
+      })
       
       steam-wrapped # Custom package
       

modules/programs/gaming/wrapper.nix

@@ -0,0 +1,37 @@
+{ stdenv, lib, makeWrapper, retroarch, cores ? [ ] }:
+
+stdenv.mkDerivation {
+  pname = "retroarch";
+  version = lib.getVersion retroarch;
+
+  nativeBuildInputs = [ makeWrapper ];
+
+  buildCommand = ''
+    mkdir -p $out/lib
+    for coreDir in $cores
+    do
+      ln -s $coreDir/* $out/lib/.
+    done
+
+    ln -s -t $out ${retroarch}/share
+
+    if [ -d ${retroarch}/Applications ]; then
+      ln -s -t $out ${retroarch}/Applications
+    fi
+
+    makeWrapper ${retroarch}/bin/retroarch $out/bin/retroarch \
+      --suffix-each LD_LIBRARY_PATH ':' "$cores" \
+      --add-flags "-L $out/lib/" \
+  '';
+
+  cores = map (x: x + x.libretroCore) cores;
+  preferLocalBuild = true;
+
+  meta = with retroarch.meta; {
+    inherit changelog description homepage license maintainers platforms;
+    longDescription =
+      "RetroArch is the reference frontend for the libretro API. The following cores are included: "
+      + lib.concatStringsSep ", " (map (x: "${x.name}") cores)
+      + ".";
+  };
+}