bash script to extract emails from txt files

gistfile1.txt

DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
TXT_FILES_DIR=$DIR/txt

#check if directory is not empty
if [ "$(ls -A $TXT_FILES_DIR)" ]; then

    #concatenate all text files in 1 log txt file
    cat $DIR/txt/*.txt > $DIR/txt_done/log.txt_"$(date +%Y%m%d-%H%M%S)".txt
    #extract emails from log.emails txt file
    egrep -o "\b[a-zA-Z0-9.-]+@[a-zA-Z0-9.-]+\.[a-zA-Z0-9.-]+\b"  $DIR/txt_done/log.txt_"$(date +%Y%m%d-%H%M%S)".txt  > $DIR/txt_done/log.emails.txt_"$(date +%Y%m%d-%H%M%S)".txt; 
    #delete all txt files in directory 
    rm -Rf $DIR/txt/*.txt
    #delete log file generated to find emails
    rm $DIR/txt_done/log.txt_"$(date +%Y%m%d-%H%M%S)".txt
else
    echo "empty directory"
fi