Move nvidia to a module

modules/system/nvidia.nix

@@ -0,0 +1,39 @@
+{ config, pkgs, lib, ... }:
+
+let
+  nvidia-offload = pkgs.writeShellScriptBin "nvidia-offload" ''
+    export __NV_PRIME_RENDER_OFFLOAD=1
+    export __NV_PRIME_RENDER_OFFLOAD_PROVIDER=NVIDIA-G0
+    export __GLX_VENDOR_LIBRARY_NAME=nvidia
+    export __VK_LAYER_NV_optimus=NVIDIA_only
+    exec "$@"
+  '';
+  cfg = config.samfelag.modules.system.nvidia;
+in
+{
+  options.samfelag.modules.system.nvidia = {
+    enable = lib.mkEnableOption "nvidia";
+
+    intelBusId = lib.mkOption { type = lib.types.str; };
+    nvidiaBusId = lib.mkOption { type = lib.types.str; };
+  };
+
+  config = lib.mkIf cfg.enable {
+    environment.systemPackages = [ nvidia-offload ];
+
+    services.xserver.videoDrivers = [ "nvidia" ];
+
+    hardware.opengl.enable = true;
+    hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.stable;
+
+    hardware.nvidia.prime = {
+      offload.enable = true;
+
+      # Bus ID of the Intel GPU. You can find it using lspci, either under 3D or VGA
+      intelBusId = cfg.intelBusId;
+
+      # Bus ID of the NVIDIA GPU. You can find it using lspci, either under 3D or VGA
+      nvidiaBusId = cfg.nvidiaBusId;
+    };
+  };
+}