#!/usr/bin/env python3
import sys
from pathlib import Path
from mutagen.flac import FLAC


def seek_and_tag(root_dir, replace=False, dry_run=False):
    root = Path(root_dir).expanduser().resolve()

    if not root.is_dir():
        print(f"Error: not a directory: {root}")
        sys.exit(1)

    for file in root.rglob("*.flac"):
        folder = file.parent.name.strip()
        if not folder:
            print(f"{file}: no parent folder name found, skipping...")
            continue
        try:
            audio = FLAC(file)

            old_genres = list(audio.get("genre", []))

            if folder in old_genres:
                print(f"{file}: folder ({folder}) already in genres, skipping...")
                continue
            new_genres = [folder] if replace else [*old_genres, folder]

            print(f"{file}:")
            print(f"  Old: {old_genres}")
            print(f"  New: {new_genres}")
            if not dry_run:
                audio["genre"] = new_genres
                audio.save()

        except Exception as e:
            print(f"{file}: Failed: {e}")


if __name__ == "__main__":
    if len(sys.argv) < 2:
        print(
            f"Usage: python {sys.argv[0]} [--replace] [--dry-run] /path/to/music",
            file=sys.stderr,
        )
        print("", file=sys.stderr)
        print("\t--dry-run: don't modify files", file=sys.stderr)
        print("\t--replace: remove original genres", file=sys.stderr)
        sys.exit(1)

    replace = "--replace" in sys.argv
    dry_run = "--dry-run" in sys.argv
    root_dir = sys.argv[-1]

    seek_and_tag(root_dir, replace=replace, dry_run=dry_run)