#!/bin/bash -eu

if [ "$(whoami)" != "root" ]
then
  echo "STOP: Run sudo -i."
  exit 1
fi

function check_variable () {
  local var_name="$1"
  if [ -z "${!var_name+x}" ]
  then
    echo "STOP: Define the variable $var_name like this: export $var_name=value"
    exit 1
  fi
}

check_variable "archiveserver"
check_variable "sharename"
check_variable "shareuser"
check_variable "sharepassword"

serverunreachable=false
ping -c 1 -w 1 "$archiveserver" 1>/dev/null 2>&1 || serverunreachable=true

if [ "$serverunreachable" = true ]
then
  echo "STOP: The archive server $archiveserver is unreachable. Try specifying its IP address instead."
  exit 1
fi

archiveserverip="$(getent hosts $archiveserver | cut -d' ' -f1)"

size="$(($(df --output=avail / | tail -1) - 1000000))"
if [ "$size" -lt 0 ]
then
  echo "STOP: The MicroSD card is too small."
  exit 1
fi

cp /boot/cmdline.txt ~
cat ~/cmdline.txt | sed 's/[[:space:]]\+modules-load=[^ [:space:]]\+//' | sed 's/rootwait/rootwait modules-load=dwc2/' > /boot/cmdline.txt
rm ~/cmdline.txt

fallocate -l "$size"K /piusb.bin
mkdosfs /piusb.bin -F 32 -I
mkdir /mnt/usb_share
mkdir /mnt/cam_archive

echo "" >> /etc/fstab
echo "/piusb.bin /mnt/usb_share vfat noauto,users,umask=000 0 0" >> /etc/fstab
echo "//$archiveserverip/$sharename /mnt/cam_archive cifs vers=3,credentials=/root/.teslaCamArchiveCredentials,iocharset=utf8,file_mode=0777,dir_mode=0777 0" >> /etc/fstab

echo "username=$shareuser" > /root/.teslaCamArchiveCredentials
echo "password=$sharepassword" >> /root/.teslaCamArchiveCredentials

mkdir /root/bin

pushd /root/bin
wget https://raw.githubusercontent.com/cimryan/teslausb/master/windows_archive/archive-teslacam-clips
chmod +x archive-teslacam-clips
wget https://raw.githubusercontent.com/cimryan/teslausb/master/windows_archive/archiveloop
chmod +x archiveloop
popd

echo "#!/bin/bash -eu" > ~/rc.local
tail -n +2 /etc/rc.local | sed '$d' >> ~/rc.local
cat << 'EOF' >> ~/rc.local
LOGFILE=/tmp/rc.local.log

function log () {
  echo "$( date )" >> "$LOGFILE"
  echo "$1" >> "$LOGFILE"
}

log "Running fsck..."
/sbin/fsck /mnt/usb_share -- -a >> "$LOGFILE" 2>&1 || echo ""
log "Running modprobe..."
/sbin/modprobe g_mass_storage >> "$LOGFILE" 2>&1
log "Launching archival script..."
/root/bin/archiveloop &
log "All done"
exit 0
EOF

cat ~/rc.local > /etc/rc.local
rm ~/rc.local

pushd /etc/modprobe.d
wget https://raw.githubusercontent.com/cimryan/teslausb/master/g_mass_storage.conf
popd