#!/bin/bash
#
# Copyright (c) 2002 by James A. McQuillan (McQuillan Systems, LLC)
#
# This software is licensed under the Gnu General Public License.
# The full text of which can be found at http://www.LTSP.org/license.txt
#

SLEEP=300

# Load LTSP configuration
. /usr/lib/ltsp/ltsp_config

#
# Figure out the SCREEN_NUM. Sure, we could do it with
# awk or some other fancy calculation, but you need to
# remember that we are running in an NFS-root filesystem,
# and we really want to avoid loading binaries like awk
# or perl across the net.
#
if [ -n "$1" ]; then
    SCREEN_NUM="$1"
    TTY_NUM=${SCREEN_NUM#0}
    TTY=/dev/tty$TTY_NUM
    exec <$TTY >$TTY 2>&1
else
    TTY=`tty`
    case ${TTY} in
      /dev/vc/1  | /dev/tty1  )  SCREEN_NUM="01";;
      /dev/vc/2  | /dev/tty2  )  SCREEN_NUM="02";;
      /dev/vc/3  | /dev/tty3  )  SCREEN_NUM="03";;
      /dev/vc/4  | /dev/tty4  )  SCREEN_NUM="04";;
      /dev/vc/5  | /dev/tty5  )  SCREEN_NUM="05";;
      /dev/vc/6  | /dev/tty6  )  SCREEN_NUM="06";;
      /dev/vc/7  | /dev/tty7  )  SCREEN_NUM="07";;
      /dev/vc/8  | /dev/tty8  )  SCREEN_NUM="08";;
      /dev/vc/9  | /dev/tty9  )  SCREEN_NUM="09";;
      /dev/vc/10 | /dev/tty10 )  SCREEN_NUM="10";;
      /dev/vc/11 | /dev/tty11 )  SCREEN_NUM="11";;
      /dev/vc/12 | /dev/tty12 )  SCREEN_NUM="12";;
    esac
fi

export SCREEN_NUM

SCREEN_VAR=SCREEN_${SCREEN_NUM}
eval SCREEN_CMD=\$$SCREEN_VAR

SCREEN_SCRIPT=`echo $SCREEN_CMD | cut -f1 -d" "`
SCREEN_ARGS=`echo $SCREEN_CMD | cut -f2- -d" " -s`

#
# Check for a missing SCREEN_01 entry in lts.conf.
# If it is missing, but they have a RUNLEVEL entry, then
# this is likely a lts.conf file from LTSP-3.0 or older.
# So, lets warn them about it, but then try to do the right thing.
#
if [ "${SCREEN_NUM}" -eq 1 ]; then
  if [ "${SCREEN_SCRIPT}" = "none" ]; then
    case "${RUNLEVEL}" in
      3)      SCREEN_SCRIPT="shell"
              SHOW_WARNING="Y"
              ;;
      none|5) SCREEN_SCRIPT="startx"
              SHOW_WARNING="Y"
              ;;
      *)      SCREEN_SCRIPT="none"
              SHOW_WARNING="Y"
              ;;
    esac
    if [ "${SHOW_WARNING}" = "Y" ]; then
      echo; echo
      echo "Warning: SCREEN_01 not set in lts.conf"
      echo "         Please have the administrator fix this!"
      echo; echo
      echo "defaulting to: ${SCREEN_SCRIPT}"
      echo
      sleep 5s
    fi
  fi
fi

if [ "${SCREEN_SCRIPT}" = "none" ]; then
    sleep ${SLEEP}
else
    if [ -x /usr/lib/ltsp/screen.d/${SCREEN_SCRIPT} ]; then
        #
        # Go ahead and run the screen script
        #
        exec /usr/lib/ltsp/screen.d/${SCREEN_SCRIPT} ${SCREEN_ARGS}
    else
        logger -t LTSP "Screen:${TTY} - SCREEN_SCRIPT: ${SCREEN_SCRIPT} not found!"
        echo "Screen:${TTY} - SCREEN_SCRIPT: ${SCREEN_SCRIPT} not found!"
        sleep ${SLEEP}
    fi
fi