#!/bin/sh
ANTIROLLBACK=/var/config/ar_clock
TIME_FILE=/tmp/time.synced

is_number() {
  [ "$1" -eq "$1" ] 2>/dev/null
}

case "$1" in
  start)
    echo "UTC" >/tmp/TZ

    # 4/18/2014 00:00:00 UTC
    timeset=1397779200

    if [ -f /etc/version ]; then
      # image creation date
      ts="$(date +%s -r /etc/version)"
      echo "Image creation time: $ts"
      if [ "$ts" -gt "$timeset" ]; then
        timeset="$ts"
      fi
    fi

    if [ -s $ANTIROLLBACK ]; then
      # last saved antirollback time
      ts="$(cat $ANTIROLLBACK)"
      # convert from floating point to integer
      ts="${ts%.*}"
      echo "Antirollback time: $ts"
      if is_number "$ts" && [ "$ts" -gt "$timeset" ]; then
        timeset="$ts"
      fi
    fi

    lasttime=$(toolbox dmesg | grep ' T: ' | (
        lasttime=0
        while IFS='[] ' read level uptime service version \
                             timestamp humandate humantime ntpsync junk; do
          if [ "$service" = "T:" ] && [ "$ntpsync" = "ntp=1" ]; then
            lasttime="$timestamp"
          fi
        done
        echo "$lasttime"
      )
    )

    if is_number "$lasttime" && [ "$lasttime" -gt 0 ]; then
      echo "Approximate time carried from last boot: $lasttime"
      if [ "$lasttime" -gt "$timeset" ]; then
        timeset="$lasttime"
      fi

      #TODO(irinams): create the TIME_FILE only when we have a way to approximate
      # how much time was spent during reboot to add it to to lasttime
      #echo >"TIME_FILE"
    fi

    echo "Setting time to $timeset"
    toolbox date +%s -s "$timeset"

    (
      wait-until-created /tmp/ntp.synced
      echo : >"$TIME_FILE"
    ) &

    if [ -f /proc/ar_clock ]; then
      babysit 60 antirollback -u bin -p $ANTIROLLBACK 2>&1 | logos rollback &
    fi
    ;;
  stop)
    pkillwait -x antirollback
    rm -f "$TIME_FILE"
    ;;
  restart|reload)
    $0 stop; $0 start
    ;;
  *)
    echo "Usage: $0 {start|stop|restart}"
    exit 1
esac