from __future__ import annotations

import argparse
import re
import urllib.request
import zipfile
from pathlib import Path

from tqdm import tqdm

from common import ROOT


URFD_URL = "https://fenix.ur.edu.pl/~mkepski/ds/uf.html"
BASE_URL = "https://fenix.ur.edu.pl/~mkepski/ds/data/"


def download(url: str, dst: Path) -> None:
    dst.parent.mkdir(parents=True, exist_ok=True)
    part = dst.with_suffix(dst.suffix + ".part")
    if part.exists():
        part.unlink()
    with urllib.request.urlopen(url) as response, open(part, "wb") as f:
        total = int(response.headers.get("Content-Length") or 0)
        with tqdm(total=total, unit="B", unit_scale=True, desc=dst.name) as bar:
            while True:
                chunk = response.read(1024 * 1024)
                if not chunk:
                    break
                f.write(chunk)
                bar.update(len(chunk))
    part.replace(dst)


def main() -> None:
    ap = argparse.ArgumentParser()
    ap.add_argument("--camera", choices=["cam0", "cam1"], default="cam0")
    ap.add_argument("--keep-zips", action="store_true")
    args = ap.parse_args()
    html = urllib.request.urlopen(URFD_URL).read().decode("utf-8", errors="ignore")
    pattern = rf"(fall-\d+-{args.camera}-rgb\.zip|adl-\d+-{args.camera}-rgb\.zip)"
    names = sorted(set(re.findall(pattern, html)))
    if args.camera == "cam1":
        names = [n for n in names if n.startswith("fall-")]
    if not names:
        raise SystemExit("No URFD RGB zip links found")
    for name in names:
        label_dir = "fall" if name.startswith("fall-") else "nonfall"
        seq = name.removesuffix(".zip")
        zip_path = ROOT / "data/raw/URFD_zips" / name
        out_dir = ROOT / "data/raw/URFD" / label_dir / seq
        if not out_dir.exists():
            if zip_path.exists() and not zipfile.is_zipfile(zip_path):
                zip_path.unlink()
            if not zip_path.exists():
                download(BASE_URL + name, zip_path)
            out_dir.mkdir(parents=True, exist_ok=True)
            with zipfile.ZipFile(zip_path) as zf:
                zf.extractall(out_dir)
        if zip_path.exists() and not args.keep_zips:
            zip_path.unlink()
    print(f"Prepared URFD RGB image sequences under {ROOT / 'data/raw/URFD'}")


if __name__ == "__main__":
    main()