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

# docs: https://nixos.wiki/wiki/Sway
let
  cfg = config.sane.gui.sway;
in
{
  options = with lib; {
    sane.gui.sway.enable = mkOption {
      default = false;
      type = types.bool;
    };
    sane.gui.sway.useGreeter = mkOption {
      description = ''
        launch sway via a greeter (like greetd's gtkgreet).
        sway is usable without a greeter, but skipping the greeter means no PAM session.
      '';
      default = true;
      type = types.bool;
    };
  };

  config = lib.mkMerge [
    {
      sane.programs.swayApps = {
        package = null;
        suggestedPrograms = [
          "guiApps"
          "splatmoji"  # used by us, but 'enabling' it gets us persistence & cfg
          "swaylock"
          "swayidle"
          "wl-clipboard"
          "blueberry"  # GUI bluetooth manager
          "mako"  # notification daemon
          # # "pavucontrol"
          # "gnome.gnome-bluetooth"  # XXX(2023/05/14): broken
          # "gnome.gnome-control-center"  # XXX(2023/06/28): depends on webkitgtk4_1
          "sway-contrib.grimshot"
          "wdisplays"  # like xrandr
        ];

        secrets.".config/sane-sway/snippets.txt" = ../../../../secrets/common/snippets.txt.bin;
      };
    }

    (lib.mkIf cfg.enable {
      sane.programs.fontconfig.enableFor.system = true;
      sane.programs.swayApps.enableFor.user.colin = true;

      sane.gui.gtk.enable = lib.mkDefault true;
      # sane.gui.gtk.gtk-theme = lib.mkDefault "Fluent-Light-compact";
      sane.gui.gtk.gtk-theme = lib.mkDefault "Tokyonight-Light-B";

      # swap in these lines to use SDDM instead of `services.greetd`.
      # services.xserver.displayManager.sddm.enable = true;
      # services.xserver.enable = true;
      sane.gui.greetd.enable = true;
      sane.gui.greetd.sway.enable = true;  # have greetd launch a sway compositor in which we host a greeter
      sane.gui.greetd.sway.gtkgreet = lib.mkIf cfg.useGreeter {
        enable = true;
        session.name = "sway-on-gtkgreet";
        session.command = "${pkgs.sway}/bin/sway --debug";
      };

      # unlike other DEs, sway configures no audio stack
      # administer with pw-cli, pw-mon, pw-top commands
      services.pipewire = {
        enable = true;
        alsa.enable = true;
        alsa.support32Bit = true;  # ??
        pulse.enable = true;
      };

      networking.useDHCP = false;
      networking.networkmanager.enable = true;
      networking.wireless.enable = lib.mkForce false;

      hardware.bluetooth.enable = true;
      services.blueman.enable = true;
      # gsd provides Rfkill, which is required for the bluetooth pane in gnome-control-center to work
      # services.gnome.gnome-settings-daemon.enable = true;
      # start the components of gsd we need at login
      # systemd.user.targets."org.gnome.SettingsDaemon.Rfkill".wantedBy = [ "graphical-session.target" ];
      # go ahead and `systemctl --user cat gnome-session-initialized.target`. i dare you.
      # the only way i can figure out how to get Rfkill to actually load is to just disable all the shit it depends on.
      # it doesn't actually seem to need ANY of them in the first place T_T
      # systemd.user.targets."gnome-session-initialized".enable = false;
      # bluez can't connect to audio devices unless pipewire is running.
      # a system service can't depend on a user service, so just launch it at graphical-session
      systemd.user.services."pipewire".wantedBy = [ "graphical-session.target" ];

      programs.sway = {
        # provides xdg-desktop-portal-wlr, which exposes on dbus:
        # - org.freedesktop.impl.portal.ScreenCast
        # - org.freedesktop.impl.portal.Screenshot
        enable = true;
        extraPackages = [];  # nixos adds swaylock, swayidle, foot, dmenu by default
        # "wrapGAppsHook wrapper to execute sway with required environment variables for GTK applications."
        wrapperFeatures.gtk = true;
      };
      # provide portals for:
      # - org.freedesktop.impl.portal.Access
      # - org.freedesktop.impl.portal.Account
      # - org.freedesktop.impl.portal.DynamicLauncher
      # - org.freedesktop.impl.portal.Email
      # - org.freedesktop.impl.portal.FileChooser
      # - org.freedesktop.impl.portal.Inhibit
      # - org.freedesktop.impl.portal.Notification
      # - org.freedesktop.impl.portal.Print
      # and conditionally (i.e. unless buildPortalsInGnome = false) for:
      # - org.freedesktop.impl.portal.AppChooser (@appchooser_iface@)
      # - org.freedesktop.impl.portal.Background (@background_iface@)
      # - org.freedesktop.impl.portal.Lockdown (@lockdown_iface@)
      # - org.freedesktop.impl.portal.RemoteDesktop (@remotedesktop_iface@)
      # - org.freedesktop.impl.portal.ScreenCast (@screencast_iface@)
      # - org.freedesktop.impl.portal.Screenshot (@screenshot_iface@)
      # - org.freedesktop.impl.portal.Settings (@settings_iface@)
      # - org.freedesktop.impl.portal.Wallpaper (@wallpaper_iface@)
      xdg.portal.extraPortals = [
        (pkgs.xdg-desktop-portal-gtk.override {
          buildPortalsInGnome = false;
        })
      ];

      sane.user.fs.".config/sway/config".symlink.text =
        import ./sway-config.nix { inherit pkgs; };

      sane.user.fs.".config/waybar/config".symlink.target =
        let
          waybar-config = import ./waybar-config.nix { inherit pkgs; };
        in
          (pkgs.formats.json {}).generate "waybar-config.json" waybar-config;

      sane.user.fs.".config/waybar/style.css".symlink.text =
        builtins.readFile ./waybar-style.css;
    })
  ];
}