Crazy dirty script to prepend all filenames in a directory with ISO8601-formatted dates

rename-8601.sh

for f in *; 
do 
    filename=$(basename "$f")
    filenamespacereplace=${filename// /-}

    filecreationdate=$(GetFileInfo -d "$f")
    truncateddate=${filecreationdate::10}
    dateslashreplace=${truncateddate////-}
    truncatedyear=${dateslashreplace:6:9}
    truncatedday=${dateslashreplace:3:2}
    truncatedmonth=${dateslashreplace::2}

    # build the correct date format
    correcteddate=$truncatedyear
    correcteddate+="-"
    correcteddate+=$truncatedmonth
    correcteddate+="-"
    correcteddate+=$truncatedday

    echo File name: $filename;
    echo Creation date: $correcteddate

    newfilename=$correcteddate
    newfilename+="-"
    newfilename+=$filenamespacereplace
    echo New name: $newfilename

    mv ./$filename $newfilename
    echo Successfully converted
done;