nichts/modules/style/gtk.mod.nix

{
  config,
  lib,
  pkgs,
  ...
}:
let
  inherit (builtins) toString isBool;
  inherit (lib.generators) toINI;
  inherit (lib.modules) mkIf;
  inherit (lib.options) mkOption mkEnableOption;
  inherit (lib.strings) escape;
  inherit (lib.trivial) boolToString;
  inherit (lib.types) str package;

  cfg = config.modules.theming.gtk;

  toGtk3Ini = toINI {
    mkKeyValue =
      key: value:
      let
        value' = if isBool value then boolToString value else toString value;
      in
      "${escape [ "=" ] key}=${value'}";
  };

  gtkIni = {
    gtk-application-prefer-dark-theme = 1;
    gtk-font-name = "Lexend 11";
    gtk-icon-theme-name = "Papirus";
    gtk-xft-antialias = 1;
    gtk-xft-hinting = 1;
    gtk-xft-hintstyle = "hintslight";
    gtk-xft-rgba = "rgb";
    gtk-cursor-theme-name = "BreezeX-RosePine-Linux";
    gtk-theme-name = "Gruvbox-Dark";
  };
in
{
  options.modules.theming.gtk = {
    enable = mkEnableOption "Wether to enable GTK theming";
    theme = {
      name = mkOption {
        description = "The GTK theme name";
        default = "Gruvbox-Dark";
        type = str;
      };
      package = mkOption {
        description = "The GTK theme package";
        default = pkgs.gruvbox-gtk-theme;
        type = package;
      };
    };
    iconTheme = {
      description = "The GTK icon theme";
      name = mkOption {
        description = "The GTK icon theme name";
        default = "Papirus";
        type = str;
      };
      package = mkOption {
        description = "The GTK icon theme package";
        default = pkgs.papirus-icon-theme;
        type = package;
      };
    };
  };
  config =
    let
      cursorSize = 32;
    in
    mkIf cfg.enable {
      programs.dconf.enable = true;
      environment = {
        systemPackages = builtins.attrValues {
          inherit (pkgs)
            rose-pine-cursor
            gruvbox-gtk-theme
            papirus-icon-theme
            colloid-icon-theme
            ;
        };
        variables = {
          GTK_THEME = cfg.theme.name;
          XCURSOR_THEME = "BreezeX-RosePine-Linux";
          XCURSOR_SIZE = cursorSize;
        };
        etc =
          let
            css = import ./gtk-colors.nix { inherit (config.modules.style.colorScheme) colors; };
          in
          {
            "xdg/gtk-4.0/settings.ini".text = toGtk3Ini {
              Settings = gtkIni;
            };
            "xdg/gtk-3.0/settings.ini".text = toGtk3Ini {
              Settings = gtkIni;
            };
            "xdg/gtk-4.0/gtk.css".text = css;
            "xdg/gtk-3.0/gtk.css".text = css;

            "xdg/gtk-2.0/gtkrc".text = ''
              gtk-cursor-theme-name = BreezeX-RosePine-Linux
              gtk-cursor-theme-size = ${toString cursorSize}
              gtk-theme-name = ${cfg.theme.name}
              gtk-icon-theme-name = ${cfg.iconTheme.name}
              gtk-font-name = Lexend 11
            '';

            "xdg/Xresources".text = ''
              Xcursor.size: ${toString cursorSize}
              Xcursor.theme: BreezeX-RosePine-Linux
            '';
          };
      };
    };
}