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

let
  dbus-sway-environment = pkgs.writeTextFile {
    name = "dbus-sway-environment";
    destination = "/bin/dbus-sway-environment";
    executable = true;

    text = ''
      dbus-update-activation-environment --systemd WAYLAND_DISPLAY XDG_CURRENT_DESKTOP=sway
      systemctl --user import-environment DISPLAY
      export STEAM_RUNTIME=0
    '';
  };

  battery-alert-swaynag = pkgs.writeShellScriptBin "battery-alert-swaynag" ''
    #!/usr/bin/env bash
    set -euo pipefail

    # Detect a battery
    cap_file=""
    status_file=""
    for d in /sys/class/power_supply/BAT*; do
      if [[ -f "$d/capacity" ]]; then
        cap_file="$d/capacity"
        status_file="$d/status"
        break
      fi
    done

    if [[ -z "$cap_file" ]]; then
      exit 0
    fi

    capacity=$(cat "$cap_file")
    status=$(cat "$status_file" 2>/dev/null || echo "Unknown")

    stamp="/run/user/$(id -u)/.battery_swaynag_stamp"
    pidfile="/run/user/$(id -u)/.battery_swaynag_pid"

    if [[ "$capacity" -lt 20 && "$status" != "Charging" && "$status" != "Full" ]]; then
      now=$(date +%s)
      last=0
      if [[ -f "$stamp" ]]; then
        last=$(cat "$stamp" 2>/dev/null || echo 0)
      fi
      # Avoid spamming: at most once every 5 minutes
      if (( now - last >= 300 )); then
        # Kill previous battery swaynag if still running
        if [[ -f "$pidfile" ]]; then
          old_pid=$(cat "$pidfile" 2>/dev/null || echo "")
          if [[ -n "$old_pid" ]] && kill -0 "$old_pid" 2>/dev/null; then
            kill "$old_pid" 2>/dev/null || true
          fi
        fi
        echo "$now" > "$stamp"
        swaynag -t warning -m "Battery low: ''${capacity}% - plug in the charger." -b "Dismiss" "true" &
        echo $! > "$pidfile"
        disown || true
      fi
    else
      # Charging or battery OK - close any existing warning bar
      if [[ -f "$pidfile" ]]; then
        old_pid=$(cat "$pidfile" 2>/dev/null || echo "")
        if [[ -n "$old_pid" ]] && kill -0 "$old_pid" 2>/dev/null; then
          kill "$old_pid" 2>/dev/null || true
        fi
        rm -f "$pidfile" "$stamp"
      fi
    fi
  '';


  sway-conf = builtins.readFile ./sway.conf + ''
    exec swaybg -m center -c 252525 -i ~/.wallpaper.png
  '';
in {
  environment.systemPackages = with pkgs; [
    dbus-sway-environment
    rofi-rbw-wayland
    swaybg
    sway-launcher-desktop
    swayidle
    swaylock
    waybar
    wayland
    wofi
    battery-alert-swaynag
  ];

  programs.sway = {
    enable = true;
    wrapperFeatures.gtk = true;
    extraOptions = [ ];
    extraSessionCommands = ''
      export WLR_NO_HARDWARE_CURSORS=1
      export WLR_RENDERER=vulkan
    '';
  };

  environment.etc = {
    "sway/config".text = sway-conf;
    "wofi/style.css".text = builtins.readFile ./wofi.css;
    "xdg/waybar/config".text = builtins.readFile ./waybar.conf;
    "xdg/waybar/style.css".text = builtins.readFile ./waybar.css;
    "xdg/foot/foot.ini".text = builtins.readFile ./foot.ini;

    # dark mode
    "xdg/gtk-2.0/gtkrc".text = "gtk-error-bell=0";
    "xdg/gtk-3.0/settings.ini".text = ''
      [Settings]
      gtk-error-bell=false
      gtk-application-prefer-dark-theme=1
    '';
    "xdg/gtk-4.0/settings.ini".text = ''
      [Settings]
      gtk-error-bell=false
      gtk-application-prefer-dark-theme=1
    '';
  };
}