{ user ? throw "user argument is required" }: { config, pkgs, ... }:

let
  hmConfig = config.home-manager.users."${user.name}";
in
{
  home-manager.users."${user.name}" = {
    home = {
      packages = with pkgs; [ swww ];
      persistence."/cache${user.home}".directories = [ "${hmConfig.xdg.relativeCacheHome}/swww" ];
    };

    theme.extraConfig = let name = "theme-swww"; in
      "${pkgs.writeShellApplication {
      inherit name;
      runtimeInputs = with pkgs; [
        coreutils-full
        swww
      ];
      text = ''
        if ! pgrep -x "swww-daemon" > /dev/null; then
          swww-daemon &> /tmp/swww.log &
        fi

        while ! swww query &> /dev/null; do
          sleep 0.1
        done

        swww img "${hmConfig.theme.configDir}/wallpaper"
      '';
    }}/bin/${name}";
  };
}