Parse and rename date in filename - shell

Question

I have some files like this:
XXXXXXXX-15Jan2014.pdf
XXXXXXXX-15Jan2015.pdf
XXXXXXXX-22Aug2013.pdf
I'd like to rename them to
XXXXXXXX-2014-01-15.pdf
XXXXXXXX-2015-01-15.pdf
XXXXXXXX-2013-08-22.pdf
That is, rename <day><month><year> to <year>-<month-as-number>-<day>.
Is there a super easy linux/osx command to do this?

Answer 1

I cant say about any command.
Try this script.
#!/bin/bash
for file in `ls`
do
FirstPart=`echo $file|rev|cut -d"-" -f2|rev`
MON=`echo $file|rev|cut -d"." -f2|rev`
date=`echo $file|rev|cut -d"-" -f1|rev`
read date year <<<${date//[^0-9]/ }
echo "$MON" | grep -i "jan" && mon=1
echo "$MON" | grep -i "feb" && mon=2
echo "$MON" | grep -i "mar" && mon=3
echo "$MON" | grep -i "apr" && mon=4
echo "$MON" | grep -i "may" && mon=5
echo "$MON" | grep -i "jun" && mon=6
echo "$MON" | grep -i "jul" && mon=7
echo "$MON" | grep -i "aug" && mon=8
echo "$MON" | grep -i "sep" && mon=9
echo "$MON" | grep -i "oct" && mon=10
echo "$MON" | grep -i "nov" && mon=11
echo "$MON" | grep -i "dec" && mon=12
newName="$FirstPart-$year-$mon-$date"
mv $file $newName
done

Answer 2

awk can help:
awk -F'[-.]' '{c="date -d" $2 " +%F"; c|getline d;close(c);printf "mv %s %s-%s.pdf\n",$0,$1, d}'
the above one-liner will generate the mv command line to do the renaming. What you can try is:
ls -1 *.pdf|awk -F'[-.]' '{c="date -d" $2 " +%F"; c|getline d;close(c);printf "mv %s %s-%s.pdf\n",$0,$1, d}'
You will see the mv ... commands as output, to execute those statements to achieve your renaming goal, just pipe the command to |sh, that is:
ls ..|awk..|sh
I picked one of your file as example:
kent$ ls -1 *.pdf
XXXXXXXX-15Jan2014.pdf
kent$ ls -1 *.pdf|awk -F'[-.]' '{c="date -d" $2 " +%F"; c|getline d;close(c);printf "mv %s %s-%s.pdf\n",$0,$1, d}'|sh
kent$ ls -1 *.pdf
XXXXXXXX-2014-01-15.pdf

Answer 3

I don't have an OSX box to test on, but this should work:
while read filename; do
prefix=${filename%-*}
ext=${filename##*.}
date=${filename##*-}; date=${date%.*}
echo mv "$filename" "$prefix-$(date -jf "%d%b%Y" "$date" "+%Y-%m-%d").$ext"
done <<END
XXXXXXXX-15Jan2014.pdf
XXXXXXXX-15Jan2015.pdf
XXXXXXXX-22Aug2013.pdf
END