bash mv every n files into different subfolders with consecutive names - bash

Question

I am trying to move n files in a directory to subdirectories. To be clear, lets say I have a folder named 1999.
I have 364 files under /1999 which are datafiles for each day. I want to move these files into subfolders named as weeks (1-52). In this case, I want to move 1st-7th files to folder named "1" ,then 8th-14th to folder named "2" and move files 358th-364th to folder named "52". So I need a loop of 7s :). How can I do this in bash or ksh?

Answer 1

Here's a pseudocode:
Get timestamp of the beginning of the year 1999 as FIRST_TS
Get timestamp of the end of the year 1999 as LAST_TS
For each file in /1999 as FILE
Get timestamp of FILE as FILE_TS
SUBFOLDER = (Integer) 52 * ((FILE_TS - FIRST_TS) / (LAST_TS - FIRST_TS)) + 1
Create folder named as /1999/SUBFOLDER if it doesn't exist
Move FILE to folder SUBFOLDER
End
Tools you can use:
* find (find /1999 -type f -maxdepth 1 ...)
* date (date -r "$FILE" '+%s')
Update:
#!/bin/bash
shopt -s extglob
YEAR=1999
ROOT=/$YEAR
for FILE in "$ROOT"/"$YEAR"_???.dat; do
N=${FILE##*_*(0)}; N=${N%.dat}; N=$(( (N - 1) / 7 + 1 ))
DEST=$ROOT/$N
[[ -d $DEST ]] || mkdir -p "$DEST" || {
echo "Failed to create destination directory \"$DEST\"." >&2
exit 1
}
mv -v -- "$FILE" "$DEST" || {
echo "Failed to move \"$FILE\" to \"$DEST\"." >&2
exit 1
}
done

Answer 2

This works for me:
#!/bin/bash
COUNTER=0
while [ $COUNTER -lt 52 ]; do
mkdir $((COUNTER + 1)) # Leave this out if the directories already exist.
mv `seq $((COUNTER*7 + 1)) $((COUNTER*7 + 7)) | xargs print "1999_%03d.dat "` $((COUNTER + 1))
COUNTER=$((COUNTER + 1))
done
But unless you want to stay a "total newbie" for ever you should try coming up with it on your own! If you can completely get everything this snippet is doing you'll be well on the way to understanding shell scripting, so try and read this code, play with it, and see what you can learn from it.