Script problem due to recursive directories Help please

Hello everyone , I am looking for a better solution then the one I have created for the my Task

The task is:
Create an automated script that will check for Uploads in a specified Directory and move them to another specified Directory if the files are completely uploaded.

Files are FTP'd to the Specified directory
Multiple FTPS could be running so knowing if a particular FTP is complete is difficult for me to check by Process ID

I created the script listed below , but can see that issues can arise with Uploads of Trees
for instance
If the Upload directory has the following:

I am not sure , but if the last changed date of the stat command on a directory is older then the Age I am looking for
then shouldn;t that mean
that any file and sub directories below that Directory will be completely uploaded and also older then the Age I am looking for ?
...... I hope that made sense....
I do not think that is the case though....

I am hoping there is a better way to deal with this issue.

Thanks for being there.

#!/bin/bash
#
#
# This script will be used to monitor uploads to a specified directory
# and move them to another directory for downloading.
#
# Things to consider:
#       1. Was the uploaded files uploaded in a sub directory.
#       2. Are the files being uploaded complete.
#       3. Move the files to the specified directory
#          with the proper permissions.
#
#
#-------------------------------------------------------------------------------#
#
# Functions
#
#-------------------------------------------------------------------------------#
calc_time() {
        AGE_LAST_CHANGED=`expr ${CURRTIME} - ${FILE_LAST_CHANGED}`
        if [ ${AGE_LAST_CHANGED} -lt ${ACCEPTED_AGE} ];
        then
                OK_TO_MOVE=N
        else
                OK_TO_MOVE=Y
        fi
}
check_date() {
        FILE_LAST_CHANGED=`stat -t ${NEWFILE} |awk '{print $13}'`
}
#-------------------------------------------------------------------------------#
#
# Vairables will go here
#
#-------------------------------------------------------------------------------#
UPUSER=up_user
DOWNUSER=down_user
#
UPPATH=/home/Private/Uploads
DOWNPATH=/home/Private/Downloads

CURRTIME=`date +%s`
ACCEPTED_AGE=300        # 5 minutes of no activity according to date modified


for f in $( ls ${UPPATH} ); do

if [ -d ${UPPATH}/${f} ];
then
#--- Directory with Subfiles In it ---#
        DIR=${UPPATH}/${f}
        echo "${DIR} is a Directory"
        DIRDATE=`date +%Y_%m_%d_%H%M%S`
        NEWDIR=${DOWNPATH}/${f}_${DIRDATE}
        NEWFILE=${DIR}
        check_date
        calc_time
                # It appears that the directory has not been changed in the allowed timeframe (ACCEPTED_AGE)
                # it is ok to create a new directory in the DOWNPATH now.
                # set permissions of new directory to the download user
        mkdir ${NEWDIR}

        # This causes a problem by leaving the original Directory present in th UPLOADS directory.

        for f2 in $(ls  ${UPPATH}/$f ); do
                NEWFILE=${DIR}/${f2} # Set becuase of check_date function
                check_date
                calc_time
                if [ ${OK_TO_MOVE} = "Y" ];
                then
                        mv ${NEWFILE} ${NEWDIR}
                        echo "mv ${NEWFILE} ${NEWDIR} "
                else
                        echo "File date is too new to move better wait"
                fi

        chown -R ${DOWNUSER}:${DOWNUSER} ${NEWDIR}
        done

else
#--- File is in Main Upload directory ---#
        if [ -f ${UPPATH}/$f ]; then
                NEWFILE=${UPPATH}/${f}
                echo "${NEWFILE} is a file"
                check_date
                calc_time

                if [ ${OK_TO_MOVE} = "Y" ];
                then
                        mv ${NEWFILE} ${DOWNPATH}
                        echo "mv ${NEWFILE} ${DOWNPATH} "
                        chown ${DOWNUSER}:${DOWNUSER} ${DOWNPATH}/*
                else
                        echo "File date is too new to move better wait"
                        echo "next pass of cronjob should move this file"
                fi
        fi
fi

done

Hello... I would tackle this problem in PERL, but for now I wanted to address options for knowing if the file upload is complete... The usual way to do this is to have the person or software that does the uploading to RENAME (ftp REN command) to another directory in the same file system. Because a RENAME (like a mv move in the shell) only changes pointers, the process is instantaneous and so if the file appears in the moved-to directory, you know it must be complete....

so for example...

../uploaddir/commitdir

You UPLOAD files to the uploaddir and when the upload is finished issue a command like ftp> REN uploadedfile commitdir/uploadedfile

Your process polls commitdir, not the uploaddir. If a file appears in commitdir, you know it must be fully uploaded and closed.

Hello quine, thanks for the response,
The problem I have is that I want to have a cron job run this script
and the directory that the files are moved to are not visible nor accessible by the uploader. Once the files are uploaded and moved, the uploader no longer has access to them. (well accept for the small timeframe between cron jobs approx. 1-5 minutes max)

A perl solution would be acceptable to me, accept I have coded only one module in perl in my life , You probably heard of it..... "Hello World"

Shell scripting I can muddle through as you can see by the script I have written so far.

So any example even in perl would benefit my issue.
thanks again