Major config overhaul: use custom modules, setup for multi-host config, and less boilerplate

modules/system/stylix/default.nix

@@ -0,0 +1,56 @@
+{ lib, config, pkgs, inputs, ... }:
+
+let
+  cfg = config.systemSettings.stylix;
+  theme = import (./. + "../../../themes"+("/"+config.systemSettings.stylix.theme));
+in
+{
+  options = {
+    systemSettings.stylix = {
+      enable = lib.mkEnableOption "Enable stylix theming";
+    };
+    systemSettings.stylix.theme = lib.mkOption {
+      default = "io";
+      type = lib.types.enum (builtins.attrNames (lib.filterAttrs (name: type: type == "directory") (builtins.readDir ../../themes)));
+      description = "Theme for stylix to use system wide. A list of themes can be found in the `themes` directory.";
+    };
+  };
+
+  imports = [ inputs.stylix.nixosModules.stylix ];
+
+  config = lib.mkIf cfg.enable {
+    stylix.enable = true;
+    stylix.autoEnable = false;
+    stylix.polarity = theme.polarity;
+    stylix.image = pkgs.fetchurl {
+     url = theme.backgroundUrl;
+     sha256 = theme.backgroundSha256;
+    };
+    stylix.base16Scheme = theme;
+    stylix.fonts = {
+      # TODO abstract fonts into an option
+      monospace = {
+        name = "FiraCode Nerd Font";
+        package = pkgs.nerd-fonts.fira-code;
+      };
+      serif = {
+        name = "FiraCode Nerd Font";
+        package = pkgs.nerd-fonts.fira-code;
+      };
+      sansSerif = {
+        name = "FiraCode Nerd Font";
+        package = pkgs.nerd-fonts.fira-code;
+      };
+      emoji = {
+        name = "Noto Color Emoji";
+        package = pkgs.noto-fonts-emoji-blob-bin;
+      };
+    };
+
+    stylix.targets.console.enable = true;
+
+    environment.sessionVariables = {
+      QT_QPA_PLATFORMTHEME = "qt5ct";
+    };
+  };
+}