games: Conditionally add emulators

This uses a crude arbitrary number to only install them onto machines
that can actually run them.

machines/nunotaba/configuration.nix

@@ -8,7 +8,10 @@
   ];
 
   sbruder = {
-    games.enable = true;
+    games = {
+      enable = true;
+      performanceIndex = 2;
+    };
     gui.enable = true;
     media-proxy.enable = true;
     mullvad.enable = true;

machines/sayuri/configuration.nix

@@ -8,7 +8,10 @@
   ];
 
   sbruder = {
-    games.enable = true;
+    games = {
+      enable = true;
+      performanceIndex = 8;
+    };
     gui.enable = true;
     media-proxy.enable = true;
     mullvad.enable = true;

modules/default.nix

@@ -12,7 +12,22 @@
       default = true;
     };
     gui.enable = lib.mkEnableOption "gui";
-    games.enable = lib.mkEnableOption "games";
+    games = {
+      enable = lib.mkEnableOption "games";
+      performanceIndex = lib.mkOption {
+        type = lib.types.int;
+        description = ''
+          Arbitrary number specifying how powerful the machine is. To be
+          replaced by taking into account single- and multi-core CPU and GPU
+          metrics separately should this system not map to my machines in
+          practice.
+
+           * 2: ~ 2014 ultrabook
+           * 8: ~ 2016 quad-core workstation with mid-range GPU
+        '';
+        default = 1;
+      };
+    };
   };
 
   # All modules are imported but non-essential modules are activated by

modules/unfree.nix

@@ -25,6 +25,8 @@ in
         "corefonts"
         "vista-fonts"
         "wallpaper-unfree" # defined in users/simon/modules/sway.nix
+        "yuzu-ea"
+        "yuzu-mainline" # derivation of icons is not allowed
       ] ++ lib.optionals cfg.allowSoftware [
         "cups-kyocera-ecosys-m552x-p502x" # exception: the file header says MIT license, but explicitly forbids modifications WTF?
         "drone-runner-exec" # exception: same as drone.io

users/simon/modules/games.nix

@@ -1,5 +1,13 @@
 { lib, nixosConfig, pkgs, ... }:
-lib.mkIf nixosConfig.sbruder.games.enable {
-  home.packages = [ ]
-    ++ lib.optional nixosConfig.sbruder.unfree.allowSoftware pkgs.unstable.osu-lazer-sandbox;
+let
+  cfg = nixosConfig.sbruder.games;
+  inherit (nixosConfig.sbruder) unfree;
+in
+lib.mkIf cfg.enable {
+  home.packages = with pkgs; [ ]
+    ++ lib.optionals (cfg.performanceIndex >= 4) [
+    desmume
+    dolphinEmuMaster
+  ] ++ lib.optional (unfree.allowAssets && cfg.performanceIndex >= 8) unstable.yuzu-ea
+    ++ lib.optional unfree.allowSoftware unstable.osu-lazer-sandbox;
 }