#!/usr/local/cpython-3.9/bin/python3

"""
This is an attempt to fix the re problem seen in music-pipeline, as an SSCCE.

In this one, we only have one compiled regex at any given time.
It is still slow.
"""

import random
import re
import string


def one_alphanum_random_string():
    """Return one alphanumeric string of 20 characters."""
    alphabet = string.ascii_letters + string.digits
    return ''.join(random.choices(alphabet, k=20))


def one_regex():
    """Return one semi-random, not-compiled regex string."""
    return r'^\./{0}/{0}/{0}\.'.format(one_alphanum_random_string())


def one_filename():
    """Return one semi-random, filename."""
    return './{0}/{0}/{0}.mp3'.format(one_alphanum_random_string())


def main():
    """Start the ball rolling."""
    regex_strings = [one_regex() for repno in range(2_046)]
    filenames = [one_filename() for repno in range(14_000)]
    matches = 0
    for regex in regex_strings:
        # Note that we _loop_ for each regex, but we only _use_ the 0th.
        compiled = re.compile(regex_strings[0])
        for filename in filenames:
            if compiled.match(filename):
                matches += 1
        del compiled
    print(matches)


main()