#!/usr/bin/env sh

# this script should not be run as root
# the polkit agent running on the desktop environment should prompt for root password

echo "---------------------------------------------------------------------------"
echo "[INFO]: Checking session"
test $(whoami) == "root" && echo "[ERROR]: Do not run this script as root." && exit 1
test -z $DISPLAY && echo "[ERROR]: DISPLAY variable is not set." && exit 1

# check session is either one of X11, Wayland or TTY
SESSION=$(loginctl show-session $(loginctl|grep $(whoami) | awk '{print $1}') -p Type | awk -F= '{print $2}' | grep "x11\|wayland\|tty")
test -z "$SESSION" && echo "[ERROR]: Failed to verify session for user, SESSION = $SESSION" && exit 1

XAUTHORITY=$(xauth info | awk -F"Authority file:" '{print $2}' | tr -d ' ')
test -z "$XAUTHORITY" && echo "[ERROR]: XAUTHORIY file is not set" && exit 1
test -s "$XAUTHORITY" || touch "$XAUTHORITY"

XAUTH_HONORED=$(xauth info | awk -F"Changes honored:" '{print $2}' | tr -d ' ')
test $XAUTH_HONORED = "yes" || echo "[ERROR]: Xauth changes honored = no, restart X server" || exit 1

# GTK_A11Y=none - fixes the dbus-launch errors with GTK4

echo "[INFO]: XAUTHORITY = $XAUTHORITY"
echo "[INFO]: DBUS_SESSION_BUS_ADDRESS = $DBUS_SESSION_BUS_ADDRESS"
echo "[INFO]: DESKTOP SESSION = $DESKTOP_SESSION"

function start_in_wayland() {
  echo "[INFO]: Starting in Wayland session"
  xauth gen $DISPLAY &> /dev/null

  case "$DESKTOP_SESSION" in
    plasma | gnome)
        pkexec env DISPLAY=$DISPLAY WAYLAND_DISPLAY="$XDG_RUNTIME_DIR/$WAYLAND_DISPLAY" XAUTHORITY=$XAUTHORITY DBUS_SESSION_BUS_ADDRESS=$DBUS_SESSION_BUS_ADDRESS GDK_BACKEND=x11 GTK_A11Y=none '/usr/share/archlinux-kernel-manager/archlinux-kernel-manager.py'
    ;;
    *)
      pkexec env DISPLAY=$DISPLAY WAYLAND_DISPLAY="$XDG_RUNTIME_DIR/$WAYLAND_DISPLAY" XAUTHORITY=$XAUTHORITY DBUS_SESSION_BUS_ADDRESS=$DBUS_SESSION_BUS_ADDRESS GTK_A11Y=none '/usr/share/archlinux-kernel-manager/archlinux-kernel-manager.py'
    ;;
  esac
}

function start_in_x11() {
  echo "[INFO]: Starting in X11 session"
  pkexec env DISPLAY=$DISPLAY XAUTHORITY=$XAUTHORITY DBUS_SESSION_BUS_ADDRESS=$DBUS_SESSION_BUS_ADDRESS GTK_A11Y=none '/usr/share/archlinux-kernel-manager/archlinux-kernel-manager.py'
}

function start_in_tty() {
  echo "[INFO]: Starting in TTY session"
  pkexec '/usr/share/archlinux-kernel-manager/archlinux-kernel-manager.py'
}

case "$SESSION" in
    "wayland")
      # Wayland session, generate Xauth session cookie for $DISPLAY
      echo "[INFO]: Display = $DISPLAY"
      echo "[INFO]: Session = $SESSION"
      start_in_wayland
    ;;
    "x11")
      # X11 session, don't do anything here
      echo "[INFO]: Display = $DISPLAY"
      echo "[INFO]: Session = $SESSION"

      # just show msg on whether the Xauth session cookie is setup
      start_in_x11
    ;;
    "tty")
      # TTY session, as user may not use a display manager
      echo "[INFO]: Display = $DISPLAY"
      echo "[INFO]: Session = $SESSION"

      start_in_tty
    ;;
    *)
      # anything here is an unknown session, fallback to XDG_SESSION_TYPE
      echo "[INFO]: Display = $DISPLAY"
      echo "[WARN]: Session could not be verified, using XDG_SESSION_TYPE"

      case "$XDG_SESSION_TYPE" in
        "wayland")
          start_in_wayland
        ;;
        "tty")
          start_in_tty
        ;;
        "x11")
          start_in_x11
        ;;
        *)
          echo "[ERROR]: $XDG_SESSION_TYPE is empty, cannot continue"
          exit 1
        ;;
      esac
    ;;
  esac
echo "---------------------------------------------------------------------------"