{
  pkgs,
  lib,
  config,
  username,
  ...
}:

let
  cfg = config.theming.md3-evo;
  homeCfg = config.home-manager.users.${username};
in
{
  options.theming.md3-evo = {
    enable = lib.mkEnableOption "the MD3-EVO theme";
    flavour = lib.mkOption {
      type = lib.types.enum [
        "content"
        "expressive"
        "fidelity"
        "fruit-salad"
        "monochrome"
        "neutral"
        "rainbow"
        "tonal-spot"
      ];
      default = "content";
      description = "The flavour of the theme";
    };
    contrast = lib.mkOption {
      type = lib.types.numbers.between (-1) 1;
      default = 0;
      description = "Use a modified contrast";
    };
    transparency = lib.mkOption {
      type = lib.types.numbers.between 0 1;
      default = 0.8;
      description = "The transparency of apps";
    };
    radius = lib.mkOption {
      type = lib.types.ints.positive;
      default = 24;
      description = "The radius of the corners";
    };
    padding = lib.mkOption {
      type = lib.types.ints.positive;
      default = 12;
      description = "The padding of the windows";
    };
    blur = lib.mkOption {
      type = lib.types.ints.positive;
      default = 16;
      description = "The blur amount of windows";
    };
  };

  config = lib.mkIf cfg.enable {
    environment = {
      systemPackages = [
        pkgs.adw-gtk3
        pkgs.matugen
        (pkgs.writeShellApplication {
          name = "theme";
          runtimeInputs = [
            pkgs.matugen
            pkgs.swww
            pkgs.gnome.zenity
          ];
          text = ''
            WALLPAPER=${homeCfg.xdg.configHome}/matugen/wallpaper

            SCHEME=$(dconf read /org/gnome/desktop/interface/color-scheme)
            if [ "$SCHEME" = "'prefer-light'" ]; then
              MODE="light"
            else
              MODE="dark"
            fi

            if [ $# -eq 0 ]; then
              echo -e "\033[1mUsage:\033[0m mode|light|dark|toggle|wallpaper"
              exit 1
            elif [ "$1" = "mode" ]; then
              echo -e "$MODE"
              exit 0
            elif [ "$1" = "wallpaper" ]; then
              if [ $# -eq 1 ]; then
                PICKED=$(zenity --file-selection --file-filter='Images | *.png *.jpg *.jpeg *.svg *.bmp *.gif')
                cp "$PICKED" "$WALLPAPER"
              else
                cp "$2" "$WALLPAPER"
              fi
            elif [ "$1" = "toggle" ]; then
              if [ "$MODE" = "light" ]; then
                MODE="dark"
              else
                MODE="light"
              fi
            elif [ "$1" = "light" ] || [ "$1" = "dark" ]; then
              MODE="$1"
            elif [ "$1" = "init" ]; then
              echo -e "\033[1mSetting up matugen\033[0m"
            else
              echo -e "\033[31mInvalid argument\033[0m"
              exit 1
            fi

            if [ ! -f $WALLPAPER ]; then
              echo -e "\033[31,1mNo wallpaper set\033[0m"
              exit 1
            fi

            if [ "$MODE" = "light" ]; then
              GTK_THEME="adw-gtk3"
            else
              GTK_THEME="adw-gtk3-dark"
            fi

            matugen image "$WALLPAPER" --type scheme-${cfg.flavour} --contrast ${builtins.toString cfg.contrast} --mode "$MODE"
            sed -i "s/set background=dark/set background=$MODE/g" ${homeCfg.xdg.configHome}/nvim/colors/md3-evo.vim

            dconf write /org/gnome/desktop/interface/gtk-theme "'$GTK_THEME'"
            dconf write /org/gnome/desktop/interface/color-scheme "'prefer-$MODE'"

            if command -v hyprctl &> /dev/null; then
              hyprctl reload
            fi

            for i in $(pgrep -u "$USER" -x nvim); do
              kill -USR1 "$i"
            done
          '';
        })
      ];
    };

    home-manager.users.${username} = {
      programs.kitty = {
        extraConfig = ''
          include ${homeCfg.xdg.configHome}/kitty/theme.conf
        '';
      };

      programs.nixvim = {
        opts.termguicolors = true;
        colorscheme = "md3-evo";
        autoCmd = [
          {
            event = [ "Signal" ];
            pattern = [ "SIGUSR1" ];
            command = "colorscheme md3-evo";
          }
        ];
      };

      gtk = {
        gtk3.extraCss = "@import './theme.css';";
        gtk4.extraCss = "@import './theme.css';";
      };

      wayland.windowManager.hyprland = {
        settings.exec-once = [
          "${pkgs.swww}/bin/swww-daemon"
          "theme init"
        ];
        extraConfig = ''
          source=./theme.conf
        '';
      };

      xdg.configFile."matugen/config.toml" = {
        onChange = ''
          theme init
        '';
        source = (pkgs.formats.toml { }).generate "matugen" {
          config = {
            reload_apps = true;
            reload_apps_list = {
              kitty = homeCfg.programs.kitty.enable;
              waybar = false;
              dunst = homeCfg.services.dunst.enable;
            };

            set_wallpaper = true;
            wallpaper_tool = "Swww";

            custom_colors = {
              red = "#ff0000";
              green = "#00ff00";
              yellow = "#ffff00";
              orange = "#ff8000";
              blue = "#0000ff";
              magenta = "#ff00ff";
              cyan = "#00ffff";

              warn = {
                color = "#ffff00";
                blend = false;
              };
              ok = {
                color = "#00ff00";
                blend = false;
              };
            };

            custom_keywords = {
              padding = builtins.toString cfg.padding;
              double_padding = builtins.toString (cfg.padding * 2);
              radius = builtins.toString cfg.radius;
              transparency = builtins.toString cfg.transparency;
              blur = builtins.toString cfg.blur;
              flavour = cfg.flavour;
              contrast = builtins.toString cfg.contrast;
              transparency_hex =
                let
                  zeroPad = hex: if builtins.stringLength hex == 1 then "0${hex}" else hex;
                in
                zeroPad (lib.trivial.toHexString (builtins.floor (cfg.transparency * 255)));
            };
          };

          templates = {
            kitty = {
              input_path = ./kitty.conf;
              output_path = "${homeCfg.xdg.configHome}/kitty/theme.conf";
            };
            nvim = {
              input_path = ./nvim.vim;
              output_path = "${homeCfg.xdg.configHome}/nvim/colors/md3-evo.vim";
            };
            hyprland = {
              input_path = ./hyprland.conf;
              output_path = "${homeCfg.xdg.configHome}/hypr/theme.conf";
            };
            anyrun = {
              input_path = ./anyrun.css;
              output_path = "${homeCfg.xdg.configHome}/anyrun/theme.css";
            };
            gtk3 = {
              input_path = ./gtk.css;
              output_path = "${homeCfg.xdg.configHome}/gtk-3.0/theme.css";
            };
            gtk4 = {
              input_path = ./gtk.css;
              output_path = "${homeCfg.xdg.configHome}/gtk-4.0/theme.css";
            };
            vesktop = {
              input_path = ./discord.css;
              output_path = "${homeCfg.xdg.configHome}/vesktop/themes/matugen.theme.css";
            };
          };
        };
      };
    };
  };
}