theming.nix

theming.nix

{ config, pkgs, lib, ... }:
with lib;
let
  fontModule = types.submodule {
    options = {
      package = mkOption {
        type = types.nullOr types.package;
        default = null;
        example = literalExample "pkgs.noto-fonts";
        description = "Font package to use. Leave unset if the font is already provided by system.";
      };
      family = mkOption {
        type = types.str;
        example = "Fira Code";
        description = "Font family.";
      };
      weight = mkOption {
        type = types.str;
        default = "Regular";
        example = "Bold";
      };
      size = mkOption {
        type = types.str;
        default = "10";
        example = "10";
        description = "Font weight to use.";
      };
      name = mkOption {
        type = types.str;
        description = "Full Pango font name. Read-only.";
        readOnly = true;
      };
    };
  };
  themeModule = types.submodule {
    options = {
      package = mkOption {
        type = types.nullOr types.package;
        default = pkgs.gnome3.gnome_themes_standard;
        example = literalExample "pkgs.gnome3.gnome_themes_standard";
        description = ''
          Package providing the theme. This package will be installed
          to your profile. If <literal>null</literal> then the theme
          is assumed to already be available in your profile.
        '';
      };

      name = mkOption {
        type = types.str;
        default = "Adwaita";
        example = "Adwaita";
        description = "The name of the theme within the package.";
      };
    };
  };
  optionalPackage = opt: optional (opt != null && opt.package != null) opt.package;
in {
  options = {
    theming = mkOption {
      description = "Centralized theming configuration.";
      type = types.submodule {
        options = {
          enable = mkEnableOption "Enable centralized theming config that universally works on all environments.";
          
          fonts = mkOption {
            description = "Font configuration.";
            type = types.submodule {
              options = {
                monospace = fontModule;
                sans = fontModule;
                otherPackages = mkOption {
                  type = types.listOf types.package;
                  default = [];
                  example = "with pkgs; [ font-awesome_5 ]";
                  description = "Additional font packages, if something in your configuration requires them.";
                };
              };
            };
          };
          icons = mkOption { description = "Icon theme configuration."; type = themeModule; };
          theme = mkOption { description = "Toolkit theme configuration."; type = themeModule; };
        };
      };
    };
  };
  config = (mkIf config.theming.enable {
    home.packages = map optionalPackage [theming.fonts.monospace theming.fonts.sans theming.fonts.otherPackages theming.icons theming.theme];
    theming.fonts = {
      monospace.name = with theming.fonts.monospace; mkDefault "${family} ${weight} ${size}";
      sans.name = with theming.fonts.sans; mkDefault "${family} ${weight} ${size}";
    };
    gtk = {
      font = {
        name = config.theming.fonts.sans.name;
      };
      theme = {
        name = config.theming.theme.name;
      };
      iconTheme = {
        name = config.theming.icons.name;
      };
    };
    qt.platformTheme = "gtk";
  });
}