#!/bin/sh

# FriendlyFileSize.sh
# 2003-10-21
# Chieh Cheng
# http://www.CynosureX.com/

# Output the file size in friendly format

# GNU General Public License (GPL), Version 2, June 1991

calculate ()
{
  size=$1

  KiB=1024
  MiB=`CalcExp.sh 1024 2`
  GiB=`CalcExp.sh 1024 3`
  TiB=`CalcExp.sh 1024 4`
  PiB=`CalcExp.sh 1024 5`
  EiB=`CalcExp.sh 1024 6`

# Can't support these two numbers yet
#  ZiB=`CalcExp.sh 1024 7`
#  YiB=`CalcExp.sh 1024 8`

  if [ $size -ge ${KiB} ]
  then
    if [ $size -ge ${MiB} ]
    then
      if [ $size -ge ${GiB} ]
      then
        if [ $size -ge ${TiB} ]
        then
          if [ $size -ge ${PiB} ]
          then
            if [ $size -ge ${EiB} ]
            then
              size=`expr $size / ${EiB}`
              echo "$size" EiB
            else
              size=`expr $size / ${PiB}`
              echo "$size" PiB
            fi
          else
            size=`expr $size / ${TiB}`
            echo "$size" TiB
          fi
        else
          size=`expr $size / ${GiB}`
          echo "$size" GiB
        fi
      else
        size=`expr $size / ${MiB}`
        echo "$size" MiB
      fi
    else
      size=`expr $size / ${KiB}`
      echo "$size" KiB
    fi
  else
    echo "$size" B
  fi
}

usage ()
{
  scriptname=`echo $0 | sed s/\\\\/.*\\\\///g`
  echo "  Usage:   $scriptname [bytes]"
}

if [ $# -gt 1 ]
then
  usage
else
  if [ $# -eq 0 ]
  then
    read size
    if [ "${size}" = "" ]
    then
      usage
    else
      calculate $size
    fi
  else
    size=$1
    calculate $size
  fi
fi