Add event summaries to ISO 8601 -like filenames from an ICS calendar

timely_rename.py

#!/usr/bin/env python3

"""
timely_rename.py

Prepend ISO 8601 -like filenames
with event summaries from an ICS calendar

(c) 2021 introt
License: Apache 2.0
"""

import re
from os import rename
from ics import Calendar
# needs 0.8.0-dev or later: https://github.com/ics-py/ics-py
from datetime import datetime as dt

# eg. 2021-11-19-Note-08-15.xopp -> ['2021', '11', '19', '08', '15']
date_pat = re.compile(r'(\d{4})-(\d{2})-(\d{2}).*?(\d{2}).(\d{2})')

def get_timely_name(filename, calendar):
    try:
        g = date_pat.match(filename).groups()
        candidates = calendar.timeline.at(dt(int(g[0]), int(g[1]), int(g[2]), int(g[3]), int(g[4])))

        name = None
        for c in candidates:
            if not name:
                name = c.summary
            else:
                print("WARNING: multiple events: choosing", name, "over", c.summary)

        return "{}-{}".format(name, filename).replace(' ', '_').replace('/', '-')

    except Exception:
        # return unchanged filename
        return filename

def timely_rename(file, verbose=True, dry_run=True):
    new = get_timely_name(file, c)

    if verbose or dry_run:
        print('"{}" -> "{}"'.format(file, new))

    if not dry_run:
        rename(file, new)

if __name__ == '__main__':
    import argparse

    parser = argparse.ArgumentParser(description='Prepend ISO 8601 -like filenames with event summaries from an ICS calendar')

    parser.add_argument('files', metavar='FILE', type=str, nargs='+', help='file(s) to rename')
    parser.add_argument('--calendar', metavar='ICSFILE', type=str, nargs=1, help='ics filename/path')
    parser.add_argument('--dry_run', help='print new filenames without renaming', action='store_true')
    parser.add_argument('--verbose', help='print old and new filenames (implied by --dry-run)', action='store_true')

    args=parser.parse_args()

    c = Calendar(''.join(open(args.calendar[0], 'r').readlines()))
    for file in args.files:
        timely_rename(file, verbose=args.verbose, dry_run=args.dry_run)

This has been an exercise in dealing with both feature creep and perfectionism - there are so many things that could be done better or made configurable, but here's a MVP for y'all to play with.

Feel free to fork! Below are some features I'd add if I had the time:

• proper filename sanitation
• configurable filename format (so one can append the event summary instead of prepending or get rid of the original name altogether)
• configurable regex
• configurable offset (eg. for cameras with misset clocks)
• get date from file metadata instead of filename
• support multiple (online) calendars
• prioritization criteria for overlapping events