#!/bin/bash

PROGNAME=$(basename $0)

OUTFILE="/tmp/ftplist.$RANDOM.txt"
CMDFILE="/tmp/ftpcmd.$RANDOM.txt"
ndays=14

print_usage() {
    echo ""
    echo "$PROGNAME - Delete files older than N days from an FTP server"
    echo ""
    echo "Usage: $PROGNAME -s -u -p -f (-d)"
    echo ""
    echo "  -s  FTP Server name"
    echo "  -u  User Name"
    echo "  -p  Password"
    echo "  -f  Folder"
    echo "  -d  Number of Days (Default: $ndays)"
    echo "  -h  Show this page"
    echo ""
    echo "Usage: $PROGNAME -h"
    echo ""
    exit
}

# Parse parameters
options=':hs:u:p:f:d:'
while getopts $options flag
do
    case $flag in
        s)
            FTPSITE=$OPTARG
            ;;
        u)
            FTPUSER=$OPTARG
            ;;
        p)
            FTPPASS=$OPTARG
            ;;
        f)
            FTPDIR=$OPTARG
            ;;
        d)
            ndays=$OPTARG
            ;;
        h)
            print_usage
            ;;
        ?)
            echo "Invalid option: -$OPTARG" >&2
            exit 1
            ;;
        :)
            echo "Option -$OPTARG requires an argument." >&2
            exit 1
            ;;
    esac
done

shift $(($OPTIND - 1))

if [[ -z "$FTPSITE" || -z "$FTPUSER" || -z "$FTPPASS" || -z "$FTPDIR" ]];
then
    echo "ERROR: Missing parameters"
    print_usage
fi


# work out our cutoff date
TDATE=`date --date="$ndays days ago" +%Y%m%d`

echo FTP Site: $FTPSITE
echo FTP User: $FTPUSER
echo FTP Password: $FTPPASS
echo FTP Folder: $FTPDIR
echo Removing files older than $TDATE

# get directory listing from remote source
ftp -i -n $FTPSITE <<EOMYF > /dev/null
user $FTPUSER $FTPPASS
binary
cd $FTPDIR
ls -l $OUTFILE
quit
EOMYF

if [ -f "$OUTFILE" ]
then

    # Load the listing file into an array
    lista=($(<$OUTFILE))

    # Create the FTP command file to delete the files
    echo "user $FTPUSER $FTPPASS" > $CMDFILE
    echo "binary" >> $CMDFILE
    echo "cd $FTPDIR"  >> $CMDFILE

    COUNT=0

    # loop over our files
    for ((FNO=0; FNO<${#lista[@]}; FNO+=9));do
        # month (element 5), day (element 6) and filename (element 8)
        FMM=${lista[`expr $FNO+5`]}
        FDD=${lista[`expr $FNO+6`]}
        FYY=${lista[`expr $FNO+7`]}

        if [[ $FYY == *:* ]]
        then
            FDATE=`date -d "$FMM $FDD" +'%Y%m%d'`
        else
            FDATE=`date -d "$FMM $FDD $FYY" +'%Y%m%d'`
        fi

        # echo $FDATE
        # check the date stamp
        if [[ $FDATE -lt $TDATE ]];
        then
            echo "Deleting ${lista[`expr $FNO+8`]}"
            echo "delete ${lista[`expr $FNO+8`]}" >> $CMDFILE
            COUNT=$[$COUNT + 1]
        fi
    done
    echo "quit" >> $CMDFILE


    if [[ $COUNT -gt 0 ]];
    then
        cat $CMDFILE | tr -d "r" > $CMDFILE
        ftp -i -n $FTPSITE < $CMDFILE > /dev/null
    else
        echo "Nothing to delete"
    fi

    rm -f $OUTFILE $CMDFILE
fi

Removing files older than 20161026
Deleting 01.10.2016
Deleting 02.10.2016
Deleting 03.10.2016
Deleting 04.10.2016
Deleting 05.10.2016
Deleting 06.10.2016
Deleting 07.10.2016
Deleting 08.10.2016
Deleting 09.10.2016
Deleting 10.10.2016
Deleting 11.10.2016
Deleting 12.10.2016
Deleting 13.10.2016
Deleting 14.10.2016
Deleting 15.10.2016
Deleting 16.10.2016
Deleting 17.10.2016
Deleting 18.10.2016
Deleting 19.10.2016
Deleting 20.10.2016
Deleting 21.10.2016
Deleting 22.10.2016
Deleting 23.10.2016
Deleting 24.10.2016
Deleting 25.10.2016
Deleting 26.10.2016