Renaming files with a specific scheme - bash

Question

I have a FTP folder receiving files from a remote camera. The camera stores the video file name always as ./rec_YYYY-MM-DD_HH-MM.mkv. The video files are stored all in the same folder, the root folder from the FTP server.
I need to move these files to another folder, with this new scheme:
Remove rec_ from the file name.
Change date format to DD-MM-YY.
Remove date from the file name and make it a folder instead, where that same file and all the others in the same date will be stored in.
Final file path would be: ./DD-MM-YYYY/HH-MM.mkv.
The process would continue to all the files, putting them in the folder corresponding to the day it was created.
Summing up: ./rec_YYYY-MM-DD_HH-MM.mkv >> ./DD-MM-YYYY/HH-MM.mkv. The same should apply to all files that are in the same folder.
As I can't make it happen directly from the camera, this needs to be done with Bash on the server that is receiving the files.
So far, what I got is script, which would get the file's creation date and use it to make a folder, and then get creation time to move the file with the new name, based on it's creation time.:
for f in *.mp4
do
mkdir "$f" "$(date -r "$f" +"%d-%m-%Y")"
mv -n "$f" "$(date -r "$f" +"%d-%m-%Y/%H-%M-%S").mp4"
done
I'm getting this output (with testfile 1.mp4):
It creates the folder based on the file's creation date;
it renames the file to it's creation time;
Then, it returns mkdir: cannot create directory ‘1.mp4’: File exists
If two or more files, only one gets renamed and moved as described. The others stay the same and terminal returns:
mkdir: cannot create directory ‘1.mp4’: File exists
mkdir: cannot create directory ‘2.mp4’: File exists
mkdir: cannot create directory ‘12-12-2018’: File exists
Could someone help me out? Better suggestions? Thanks!

Answer 1

Honestly I would just use Perl or Python for this. Here's how to embed either in a shell script.
Here's a perl script that doesn't use any libraries, even ones that ship with Perl (so it'll work without extra packages on distributions like CentOS that don't ship with the entire Perl library). The perl script launches one new process per file in order to perform the copy.
perl -e '
while (<"*.m{p4,kv}">) {
my $path = $_;
my ($prefix, $year, $month, $day, $hour, $minute, $ext) =
split /[.-_]/, $path;
my $sec = q[00];
die "unexpected prefix ($prefix) in $path"
unless $prefix eq q[rec];
die "unexpected extension ($ext) in $path"
unless $ext eq q[mp4] or $ext eq q[mkv];
my $dir = "$day-$month-$year";
my $name = "$hour-$min-$sec" . q[.] . $ext;
my $destpath = $dir . q[/] . $name;
die "$dir . $name is unexpectedly a directory" if (-d $dir);
system("cp", "--", $path, $destpath);
}
'
Here's a Python example, it's compatible with either Python 2 or Python 3 but does use the standard library. The Python script does not spawn any additional processes.
python3 -c '
import os.path as path
import re
from glob import iglob
from itertools import chain
from os import mkdir
from shutil import copyfile
for p in chain(iglob("*.mp4"), iglob("*.mkv")):
fields = re.split("[-]|[._]", p)
prefix = fields[0]
year = fields[1]
month = fields[2]
day = fields[3]
hour = fields[4]
minute = fields[5]
ext = fields[6]
sec = "00"
assert prefix == "rec"
assert ext in ["mp4", "mkv"]
directory = "".join([day, "-", month, "-", year])
name = "".join([hour, "-", minute, "-", sec, ".", ext])
destpath = "".join([directory, "/", name])
assert not path.isdir(destpath)
try:
mkdir(directory)
except FileExistsError:
pass
copyfile(src=p, dst=destpath)
'
Finally, here's a bash solution. It splits paths using -, ., and _ and then extracts various subfields by indexing into $# inside a function. The indexing trick is portable, although regex substitution on variables is a bash extension.
#!/bin/bash
# $1 $2 $3 $4 $5 $6 $7 $8
# path rec YY MM DD HH MM ext
process_file() {
mkdir "$5-$4-$3" &> /dev/null
cp -- "$1" "$5-$4-$3"/"$6-$7-00.$8"
}
for path in *.m{p4,kv}; do
[ -e "$path" ] || continue
# NOTE: two slashes are needed in the substitution to replace everything
# read -a ARRAYVAR <<< ... reads the words of a string into an array
IFS=' ' read -a f <<< "${path//[-_.]/ }"
process_file "$path" "${f[#]}"
done

Answer 2

If you cd /to/some/directory/containing_your_files then you could use the following script
#!/usr/bin/env bash
for f in rec_????-??-??_??-??.m{p4,kv} ; do
dir=${f:4:10} # skip 4 chars ('rec_') take 10 chars ('YYYY_MM_DD')
fnm=${f:15} # skip 15 chars, take the remainder
test -d "$dir" || mkdir "$dir"
mv "$f" "$dir"/"$fnm"
done
note ① that I have not exchanged the years and the days, if you absolutely need to do the swap you can extract the year like this, year=${dir::4} etc and ② that this method of parameter substitution is a Bash-ism, e.g., it doesn't work in dash.

Answer 3

your problem is: mkdir creates folder but you are giving filename for folder creation.
if you want to use fileName for folder creation then use it without extension.
the thing is you are trying to create folder with the already existing fileName