import argparse
import logging
import os
import shutil
import subprocess
import tempfile
from pathlib import Path


def find_editor() -> str:
    editor = os.getenv("EDITOR")
    if editor:
        return editor

    for candidate in ["micro", "nano"]:
        if shutil.which(candidate):
            return candidate

    return "nano"


def edit_text(text: str) -> str | None:
    with tempfile.NamedTemporaryFile(suffix=".tmp", delete=False) as tf:
        temp_file_path = Path(tf.name)
        temp_file_path.write_text(text)

        old_modtime = temp_file_path.stat().st_mtime
        subprocess.call([*find_editor().split(), str(temp_file_path)])
        new_modtime = temp_file_path.stat().st_mtime
        if new_modtime == old_modtime:
            logging.warning("editor exited without saving")
            return None

        return temp_file_path.read_text()


def move_to_trash(file_path: Path):
    if not file_path.is_file():
        raise FileNotFoundError

    subprocess.run(
        [
            "osascript",
            "-e",
            f'tell app "Finder" to move POSIX file "{file_path}" to trash',
        ],
        check=True,
    )


def rename_files(files: list[Path], cwd: Path | None = None):
    if not cwd:
        cwd = files[0].parent

    originals = [f"{f.relative_to(cwd)}" for f in files]
    edited_raw = edit_text("\n".join(originals))
    if not edited_raw:
        return
    edited = edited_raw.splitlines(keepends=False)

    deletables = []
    moveables = []
    for source, target in zip(originals, edited):
        if target.startswith("#") or target == "":
            deletables.append(Path(source))
            continue
        if source != target:
            moveables.append((cwd / source, cwd / target))

    for source, target in moveables:
        logging.info(f"moving {source} -> {target}")
        source.rename(target)

    for f in deletables:
        try:
            logging.info(f"trashing {f}")
            move_to_trash(f)
        except:
            logging.error(f"failed to trash {f}")


def parse_args():
    arger = argparse.ArgumentParser()
    arger.add_argument("filenames", type=Path, nargs="+", help="File paths")
    arger.add_argument("--cwd", type=Path, help="Current working directory")
    return arger.parse_args()


def main():
    args = parse_args()
    rename_files(args.filenames, cwd=args.cwd)


if __name__ == "__main__":
    logging.basicConfig(level=logging.INFO)
    main()