set_attribute.py

#!/usr/bin/env python3

import argparse
import sys
from contextlib import suppress

from _utils import get_attribute, set_attribute

HELP = """
For a list of ultrastar text files, set an attribute like #VIDEO to the given
value. Prints the paths of all changed files. Only accepts UTF-8 encoded files.
"""


def main(argv):
    parser = argparse.ArgumentParser(description=HELP)
    parser.add_argument("attribute")
    parser.add_argument("value")
    parser.add_argument("files", nargs="+")
    parser.add_argument("--search", help="only replace, if the old value matches")
    parser.add_argument("--dry-run", action="store_true")
    args = parser.parse_args(argv)

    for path in args.files:
        with open(path) as f:
            text = f.read()
            try:
                value = get_attribute(text, args.attribute)
            except:
                value = None
            if args.search and value != args.search:
                continue
            if value == args.value:
                continue
            lines = set_attribute(text.splitlines(), args.attribute, args.value)

        if not args.dry_run:
            with open(path, "w") as f:
                f.writelines(lines)

        print(path)


if __name__ == "__main__":
    main(sys.argv[1:])