post_install() {
  # Add vboxusers group, GID 108 is reserved (http://wiki.archlinux.org/index.php/UID_and_GID_list),
  getent group vboxusers &> /dev/null || groupadd -f -g 108 vboxusers

  # Load new udev rule for module vboxdrv
  udevadm control --reload-rules

  # Update mime database
  [[ -x =update-mime-database ]] && update-mime-database /usr/share/mime &>/dev/null

  # Update desktop database
  [[ -x =update-desktop-database ]] && update-desktop-database -q &>/dev/null

  # Build new module
  /usr/bin/vboxsetup setup
  
  # Show warnings
  /bin/cat <<EOF

==> Remember to add allowed users to the vboxusers group:
==> # gpasswd -a USERNAME vboxusers
==>
==> To load virtualbox modules automatically you can add vboxdrv to a file /etc/modules-load.d/vbox.conf
==> To start virtualbox web service automatically you need to enable and start the service through systemctl
==>
==> To fix missing usb devices, you can call 'vboxsetup fixusb' or reboot your computer
EOF
}

pre_upgrade() {
  pre_remove 

  # Remove any stuff remaining from the module compilation
  rm -Rf "/opt/VirtualBox"
}

post_upgrade() {
  post_install
}

pre_remove() {
  # Stop running services
  _service="vboxweb.service"
  systemctl is-active ${_service} &>/dev/null
  if [[ $? -eq 0 ]] ; then
	systemctl stop ${_service}
  fi
  systemctl is-enabled ${_service} &>/dev/null
  if [[ $? -eq 0 ]] ; then
	systemctl disable ${_service}
  fi
  
  # Remove modules
  if [ $(vercmp $2 4.2.0-4) -lt 0 ]; then
    /usr/bin/vboxsetup remove
  elif [[ -f /etc/rc.d/vboxdrv && -f /usr/sbin/rc.d ]]; then
    rc.d unload vboxdrv
    rc.d remove vboxdrv
  else
    echo -e "\n==> Modules could not be deleted. Please check manually.\n"
  fi
}

post_remove() {
  # Remove any stuff remaining from the module compilation
  rm -Rf "/opt/VirtualBox"
  
  # Remove any run files
  rm -Rf "/var/run/VirtualBox"

  # Update mime database
  [[ -x =update-mime-database ]] && update-mime-database /usr/share/mime &>/dev/null

  # Update desktop database
  [[ -x =update-desktop-database ]] && update-desktop-database -q &>/dev/null

  # remove vboxusers group
  groupdel vboxusers &>/dev/null || true
}