import argparse
import re
import typing

import symuid


def _walk_track_attrs(path, path_ignore_regex) -> typing.Iterator[dict]:
    for track in symuid.Track.walk(path, path_ignore_regex):
        yield {
            "path": track.path,
            "comment": track.comment,
            "play_count": track.get_play_count_sum(),
        }


def _init_argparser():
    argparser = argparse.ArgumentParser(description="filter & sort tracks")
    argparser.add_argument("path")
    argparser.add_argument(
        "--path-ignore-regex",
        default=symuid.Track.PATH_DEFAULT_IGNORE_REGEX,
        dest="path_ignore_regex",
        nargs=1,
        type=re.compile,
        metavar="pattern",
        help="(default: %(default)s)",
    )
    argparser.add_argument(
        "--filter",
        metavar="expression",
        dest="filter_expression",
        help="(example: {!r} or {!r})".format(
            "play_count > 16 and path.endswith('.mp3')",
            "comment is None or len(comment) < 16",
        ),
    )
    argparser.add_argument(
        "--sort",
        metavar="expression",
        dest="sort_expression",
        help="(example: {!r} or {!r})".format(
            "play_count * -1", "(play_count, len(path))",
        ),
    )
    argparser.add_argument(
        "--limit", type=int, help="(default: none)",
    )
    argparser.add_argument(
        "--prefix",
        type=str,
        default="",
        help="add prefix to each resulting path (default: %(default)r)",
    )
    return argparser


def _main():
    args = _init_argparser().parse_args()
    # use generators until sort is required
    track_attrs = _walk_track_attrs(
        path=args.path, path_ignore_regex=args.path_ignore_regex
    )
    # pylint: disable=eval-used
    if args.filter_expression:
        track_attrs = filter(lambda a: eval(args.filter_expression, a), track_attrs)
    if args.sort_expression:
        track_attrs = sorted(track_attrs, key=lambda a: eval(args.sort_expression, a))
    for track_index, attr in enumerate(track_attrs):
        if args.limit and track_index == args.limit:
            break
        print(args.prefix + attr["path"])