Shell Program to manage scp xfers

scp_xfers

#!/bin/bash
#GLOBAL VARS
set -x
DATE=`date +%Y-%m-%d.%H:%M:%S`
RECIPIENTS="user@domain.com"
STAGING=/nas/tbdata/.encrypted_file
EXTRACT=/nas/tbdata2
ARCHIVE=/nas/tbdata/.encrypted_file/md5
MD5="user@obfuscated.domain.com:/erp.tar.gpg.md5"
DATA="user@obfuscated.domain.com:/erp.tar.gpg"
KEY=$HOME/.ssh/tb
#clean up the previous jobs files
clean_up() {

    rm $1/erp.tar
    rm -rf $2/erp
    rm $1/erp.tar.gpg
}

#pull down current md5 & statge, then assign GLOBAL VARS to compare
copy_md5() {
    scp -o ConnectTimeout=30 -P 2222 -i $KEY $1 $2
    NEW=$(cat $2/erp.tar.gpg.md5 | awk '{print $1}')
    OLD=$(cat $3/erp.tar.gpg.md5 | awk '{print $1}')
}

#scp erp data and do work to extract
copy_erp() {
    scp -P 2222 -i $KEY $3 $1
    gpg -o $1/erp.tar -d $1/erp.tar.gpg
    tar -xf $1/erp.tar -C $2
    mv $1/erp.tar.gpg.md5 $4
    cp $4/erp.tar.gpg.md5 $4/erp.tar.gpg.md5_$(date +%Y-%m-%d.%H:%M:%S)
    echo "Subject: file transfer was successful MD5=$NEW" 
    stat $2
    tree -s $2
}
#function is ran IF OLD == NEW
skip_job() {
    echo "Subject: Run skipped MD5's the same:"
    echo "Archived MD5: `echo $OLD`"
    echo "Downloaded MD5: `echo $NEW`"
    rm -vf $2/erp.tar.gpg.md5
    stat $EXTRACT
    tree -s $EXTRACT
}


######
copy_md5 $MD5 $STAGING $ARCHIVE
#if an OLD hash does not exist, then we copy ERP data
if [ -z $OLD ]
then
    clean_up $STAGING $EXTRACT
    copy_erp $STAGING $EXTRACT $DATA $ARCHIVE
#else OLD == NEW we skip_job()
else
    if [ $OLD = $NEW ]
    then
        skip_job $ARCHIVE $STAGING
    else
#condition is TRUE else OLD != NEW
        clean_up $STAGING $EXTRACT
        copy_erp $STAGING $EXTRACT $DATA $ARCHIVE
    fi
fi