octoprint_install_routine(){
  #experimental new dependency check
    octoprint_dependencies
  #execute operations
  install_octoprint
  add_groups
  configure_autostart
  add_reboot_permission
  load_server
}

octoprint_dependencies(){
  octo_dep=(
    python-pip
    python-dev
    python-setuptools
    python-virtualenv
    git
    libyaml-dev
    build-essential
    wget
  )
  status_msg "Checking for dependencies ..."
  for octo_dep_pgk in "${octo_dep[@]}"
  do
    if [[ $(dpkg-query -f'${Status}' --show $octo_dep_pgk 2>/dev/null) = *\ installed ]]; then
      install+=($octo_dep_pgk)
    fi
  done
  if ! [ ${#install[@]} -eq 0 ]; then
    status_msg "Installing dependencies ..."
    sudo apt-get install ${install[@]} -y && ok_msg "Dependencies installed!"
  else
    ok_msg "All dependencies already met!"
  fi
}

install_octoprint(){
  if [ ! -d $OCTOPRINT_DIR ];then
    status_msg "Create Octoprint directory ..."
    mkdir -p $OCTOPRINT_DIR && ok_msg "Directory created!"
  fi
  cd $OCTOPRINT_DIR
  #create the virtualenv
  status_msg "Set up virtualenv ..."
  virtualenv venv
  source venv/bin/activate
  #install octoprint with pip
  status_msg "Download and install octoprint ..."
  pip install pip --upgrade
  pip install --no-cache-dir octoprint
  ok_msg "Download complete!"
  #leave virtualenv
  deactivate
}

add_groups(){
  USER=$(whoami)
  if [[ ! $(groups | grep tty) ]]; then
    status_msg "Adding the current user to group 'tty' ..."
    sudo usermod -a -G tty $USER && ok_msg "Done!"
  fi
  if [[ ! $(groups | grep tty) ]]; then
    status_msg "Adding the current user to group 'dialout' ..."
    sudo usermod -a -G dialout $USER && ok_msg "Done!"
  fi
}

configure_autostart(){
  USER=$(whoami)
  cd $OCTOPRINT_DIR
  status_msg "Downloading files ..."
  wget https://github.com/foosel/OctoPrint/raw/master/scripts/octoprint.init
  wget https://github.com/foosel/OctoPrint/raw/master/scripts/octoprint.default
  ok_msg "Files downloaded successfully!"
  #make necessary changes in default file
  status_msg "Configure octoprint service ..."
  DEFAULT_FILE=$OCTOPRINT_DIR/octoprint.default
  sed -i "s/pi/$USER/g" $DEFAULT_FILE
  sed -i "s/#BASEDIR=/BASEDIR=/" $DEFAULT_FILE
  sed -i "s/#CONFIGFILE=/CONFIGFILE=/" $DEFAULT_FILE
  sed -i "s/#DAEMON=/DAEMON=/" $DEFAULT_FILE
  #move files to correct location
  sudo mv octoprint.init $OCTOPRINT_SERVICE1
  sudo mv octoprint.default $OCTOPRINT_SERVICE2
  #make file in init.d executable
  sudo chmod +x $OCTOPRINT_SERVICE1
  status_msg "Reload systemd configuration files"
  sudo update-rc.d octoprint defaults
  sudo systemctl daemon-reload
  ok_msg "Configuration complete!"
  ok_msg "Octoprint installed!"
}

add_reboot_permission(){
  USER=$(whoami)
  #create a backup when file already exists
  if [ -f /etc/sudoers.d/octoprint-shutdown ]; then
    sudo mv /etc/sudoers.d/octoprint-shutdown /etc/sudoers.d/octoprint-shutdown.old
  fi
  #create new permission file
  status_msg "Add reboot permission to user '$USER' ..."
  cd $OCTOPRINT_DIR
  echo "$USER ALL=NOPASSWD: /sbin/shutdown" > octoprint-shutdown
  sudo chown 0 octoprint-shutdown
  sudo mv octoprint-shutdown /etc/sudoers.d/octoprint-shutdown
  ok_msg "Permission set!"
  sleep 2
}

load_server(){
  start_octoprint
  #create an octoprint.log symlink in home-dir just for convenience
  if [ ! -e ${HOME}/octoprint.log ]; then
      status_msg "Creating octoprint.log symlink ..."
      ln -s ${HOME}/.octoprint/logs/octoprint.log ${HOME}/octoprint.log && ok_msg "Symlink created!"
  fi
  ok_msg "Octoprint is now running on:"
  ok_msg "$(hostname -I | cut -d " " -f1):5000 or"
  ok_msg "http://localhost:5000"; echo
}