feat: add nix integration

flake.nix

@@ -0,0 +1,46 @@
+{
+  description = "OpenVPN 3 Indicator for the Systray";
+
+  inputs.nixpkgs.url = "nixpkgs/nixos-unstable";
+
+  outputs = { self, nixpkgs, nur }:
+    let
+      supportedSystems = [ "x86_64-linux" "aarch64-linux" ];
+      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
+    in
+    {
+
+      # Provide some binary packages for selected system types.
+      packages = forAllSystems
+        (system:
+          let
+            pkgs = import nixpkgs {
+              inherit system;
+            };
+          in
+          {
+            openvpn3-applet = pkgs.stdenv.mkDerivation
+              {
+                name = "openvpn3-applet";
+                src = ./.;
+                nativeBuildInputs = [
+                  pkgs.yad
+                ];
+                installPhase = ''
+                  install -d $out
+                  install -d $out/bin
+                  install -d $out/share/applications
+
+                  cp -R src/ $out
+                  ln -s $out/src/openvpn3applet.sh $out/bin/openvpn3applet
+
+                  NESTO_BIN_PATH=$out/bin/openvpn3applet
+                  sed "s#@execPath@#$NESTO_BIN_PATH#" xdg-config/autostart/openvpn3-applet.desktop.in > $out/share/applications/openvpn3-applet.desktop
+                '';
+              };
+          }
+        );
+
+      defaultPackage = forAllSystems (system: self.packages.${system}.openvpn3-applet);
+    };
+}

xdg-config/autostart/openvpn3-applet.desktop.in

@@ -0,0 +1,7 @@
+[Desktop Entry]
+Exec=sh -c '@execPath@'
+Icon=
+Name=openvpn3-applet
+Path=
+Terminal=False
+Type=Application