Shell Programming and Scripting

#!/bin/bash
HOST='ftp.npq.net'
USER='xyz'
PASSWD='abc'
UNZIP='unzip $FILE'
LIST='ls -al'
#File_List='`ls -al`'
export Env="?TBD?";

## Set the following variable.
##
set_Env ()
{
 ## Fetching the Env from where the Build deliverable requiered (last option).
prompt_Env;
}

prompt_Env ()
{
echo -e "\nSelect the Enviornment Name\n";
sleep 1;
select Env in dv pf qa ig pp pn exit;
 do
  if [[ -n ${Env} ]]; then
    echo -e "\n\n - You selected: \"${Env}\"\n"
    break;
  else
    echo -e "\n\n - Invalid selection \"${REPLY}\"...Please try again.\n";
  fi
done
 if [[ ${Env} == "exit" ]]; then
  summary=$(
  echo -e "\n#################### FTP process - Aborted ####################\n";
  echo -e "Warning: User gracefully selected \"${Env}\" option to abort the script operation. Exiting with exit_code=151.";);
  echo "${summary}";
  exit 0;
  fi
}
#prompt_env;
#echo -e "Enter the Name of the file:";
#read FILE;
#DIRECTORY=TRAM/"${Env}"
#if [[ -z ${1} ]]; then
#prompt_env;
#fi

#set "${@}";
for ((i=1;$#>=$i;i++))
do
  argn="\${"$i"}";
  argn="$(eval echo $argn)";
  case "${argn%%=*}=" in
  "Env=")
   Env="${argn#*=}";
   Env="${Env:=?TBD?}";
  ;;
 esac
done

## Check arguments and set them if reqd.
## -------------------------------------

for arg in "Env=${Env}";
do
  ## Get Var=Val pair
  var="${arg%=*}";
  val="${arg#*=}";

  ## Check if mandatory params are not valid, set them if reqd.
  if [[ "${val}" == "?TBD?" ]]; then
     set_${var};
  fi
done

DIRECTORY=TRAM/"${Env}"

echo -n "ENTER the name of the file:";
read FILE
ftp -n $HOST << EOT
ascii
user $USER $PASSWD
cd $DIRECTORY
$LIST
get $FILE
bye
EOT
unzip $FILE
rm $FILE