discover-overlay: refactor

Apply suggestions from code review

Co-authored-by: éclairevoyant <848000+eclairevoyant@users.noreply.github.com>

pkgs/by-name/di/discover-overlay/package.nix

@@ -1,4 +1,4 @@
-{ lib, python3, fetchFromGitHub, gtk3, gobject-introspection, wrapGAppsHook }:
+{ lib, python3, fetchFromGitHub, gtk3, gobject-introspection, gtk-layer-shell, wrapGAppsHook }:
 python3.pkgs.buildPythonApplication rec {
   pname = "discover-overlay";
   version = "0.7.0";
@@ -11,7 +11,10 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-//QW6N87Uhm2aH0RSuykHG3+EfzYSHOcSNLSn1y0rFw=";
   };
 
-  buildInputs = [ gtk3 ];
+  buildInputs = [
+    gtk3
+    gtk-layer-shell
+  ];
 
   nativeBuildInputs = with python3.pkgs; [
     gobject-introspection
@@ -29,16 +32,20 @@ python3.pkgs.buildPythonApplication rec {
     pyxdg
     requests
     pillow
+    setuptools
     xlib
   ];
-
+  postPatch = ''
+    substituteInPlace discover_overlay/image_getter.py \
+      --replace-fail /usr $out
+  '';
   doCheck = false;
 
   meta = {
     description = "Yet another discord overlay for linux";
     homepage = "https://github.com/trigg/Discover";
     license = lib.licenses.gpl3Only;
     maintainers = with lib.maintainers; [ dragonginger ];
-    mainProgram = "discover";
+    mainProgram = "discover-overlay";
   };
 }