#!/usr/bin/env sh
set -o errexit

: "${XDG_CONFIG_HOME:="$HOME/.config"}"

config_file="$XDG_CONFIG_HOME/fhnw-sync/config"
config_read=false

set_defaults() {
  ad_mount_dir="/mnt/fhnw-share"
  ad_dest_dir="$HOME/documents/fhnw/ad"
  ad_excluded_files=".DS_Store|Thumbs.db"
  ad_sources=""
  teams_dest_dir="$HOME/documents/fhnw/teams"
  teams_sources=""
  pass_path="accounts/fhnw/students.fhnw.ch"
}

read_config() {
  if [ -f "$config_file" ]; then
    # shellcheck disable=1090
    . "$config_file"
  fi
}

display_help() {
  set_defaults
  echo "Usage: $0 [option...] " >&2
  echo
  echo "   -c,   config file [default: $config_file]"
  echo "   -m,   mount directory for the ad [default: $ad_mount_dir]"
  echo "   -d,   root destination directory [default: $ad_dest_dir]"
  echo "   -e,   list of excluded files in ad sync (pipe separated) [default: $ad_excluded_files]"
  echo "   -s,   list of ad directories, relative to the mount directory that will be synced (pipe separated)"
  echo "   -r,   root destination directory for teams sync [default: $teams_dest_dir]"
  echo "   -t,   list of configured rclone teams sources (pipe separated)"
  echo "   -p,   path for pass to get user and password information [default: $pass_path]"
  echo "   -h,   display this help and exit"
  echo
  echo "If a config file exists, it is sourced by this script. The following keys are recognized:"
  echo "- ad_mount_dir -> m"
  echo "- ad_dest_dir -> d"
  echo "- ad_excluded_files -> e"
  echo "- ad_sources -> s"
  echo "- teams_dest_dir -> r"
  echo "- teams_sources -> t"
  echo "- pass_path -> p"
  echo
  echo "Values from a config file get overwriten by cli args."
  echo
}

parse_args() {
  while getopts ":hc:m:d:e:s:r:t:p:" opt; do
    case $opt in
    h)
      display_help
      exit 0
      ;;
    c)
      if [ $config_read = false ]; then
        config_file=$OPTARG
        read_config
        config_read=true
        parse_args "$@"
      fi
      ;;
    m)
      ad_mount_dir=$OPTARG
      ;;
    d)
      ad_dest_dir=$OPTARG
      ;;
    e)
      ad_excluded_files=$OPTARG
      ;;
    s)
      ad_sources=$OPTARG
      ;;
    r)
      teams_dest_dir=$OPTARG
      ;;
    t)
      teams_sources=$OPTARG
      ;;
    p)
      pass_path=$OPTARG
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      display_help
      exit 1
      ;;
    :)
      echo "Option -$OPTARG requires an argument." >&2
      display_help
      exit 1
      ;;
    esac
  done
}

cleanup() {
  if mountpoint -q "$ad_mount_dir"; then
    echo "unmounting ad share..."
    sudo umount --quiet "$ad_mount_dir" || true
  fi

  if [ -f "$vpn_pid_file" ]; then
    echo "stopping vpn..."
    vpn_pid="$(sudo cat "$vpn_pid_file")"
    sudo kill "$vpn_pid"
    while ps -p "$vpn_pid" >/dev/null; do
      sleep 1
    done
  fi
}
trap cleanup 0 HUP INT QUIT ABRT TERM

start_vpn() {
  echo "starting vpn..."
  vpn_pid_file="$(sudo mktemp)"
  fhnw-vpn -m "bg" -t "$vpn_pid_file" -p "$pass_path"
}

set_defaults
read_config
parse_args "$@"
start_vpn
fhnw-ad-mount -m "$ad_mount_dir" -p "$pass_path"
fhnw-ad-sync -m "$ad_mount_dir" -d "$ad_dest_dir" -e "$ad_excluded_files" -s "$ad_sources"
fhnw-teams-sync -d "$teams_dest_dir" -s "$teams_sources"