#!/bin/bash

function helpexit() {
    echo "Start a Docker session with LXDE and VNC server."
    echo "NOTE: Docker image is stopped and destroyed when ssh shell exits!"
    echo "  --vnc            Start VNC viewer"
    echo "  --geometry WxY   VNC Default screen size"
    echo "  --new-passwd     Generate new random VNC password file"
    echo "  --persistent     Do not remove container at exit"
    echo "  --help   This help"
    exit
}
function pwgen() {
  dd if=/dev/random of=vnc_passwd bs=1 count=8
}
function rsagen() {
  rm -f .id_rsa .id_rsa.pub
  ssh-keygen -t rsa -b 1024 -N "" -f .id_rsa
}
RMIMAGE="--rm"
for (( i=1; i<=$#; i++ )); do
  j=$(( $i + 1 ))
  [[ "${!i}" = "--help" ]] && helpexit                                            
  [[ "${!i}" = "-h" ]] && helpexit                                            
  [[ "${!i}" = "--vnc" ]] && { VNC=1; continue; }
  [[ "${!i}" = "--new-passwd" ]] && { pwgen; continue; }
  [[ "${!i}" = "--persistent" ]] && { RMIMAGE=""; continue; }
  [[ "${!i}" = "--geometry" ]] && { 
      VNCSIZE="-geometry ${!j}"; 
      [[ "$VNCSIZE" = *x* ]] || {
        echo "VNC geometry must be of format WxH, e.g. 1024x768"
        exit 1
      }
      continue; 
  }
done
set -e
[[ -f .id_rsa.pub ]] || rsagen
[[ -f .id_rsa ]] || rsagen


cd $( dirname $( readlink -f $0 ) )

export USER=$( id -u -n )
export USERID=$( id -u )
export USERGID=$( id -u )
cat userinit.sh.template | \
  sed 's,--USER--,'$USER',g' | \
  sed 's,--USERID--,'$USERID',g' | \
  sed 's,--USERGID--,'$USERGID',g' | \
  sed 's,--PUBKEY--,'"$( cat .id_rsa.pub )"',' > userinit.sh

chmod 755 userinit.sh

image=$( basename $( dirname $( readlink -f $0 ) ) )
echo $image

docker build -t $image . 
nname=$image$$

docker run $RMIMAGE -v /mnt:/mnt -v /media:/media -v $HOME/:/host_home  \
    --privileged \
    -h $nname --name $nname $image \
    bash /bootstuff.sh $USER &
    
echo $nname    
while :; do
  sleep 3
  IP=$( docker inspect --format '{{ .NetworkSettings.IPAddress }}' $nname )
  [[ -z "$IP" ]] || break
done
echo $IP
while :; do
  sleep 3
  ssh-keyscan $IP && break
done

ssh -i .id_rsa -XY -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no $USER@$IP #&& break
echo "Shutting down $nname"
sleep 1
docker stop $nname >/dev/null &