#!/usr/bin/env python3
"""Prepare vocab and normalization stats for HAI 21.03."""

import json
from pathlib import Path
from typing import Optional

from data_utils import compute_cont_stats, build_disc_stats, load_split
from platform_utils import safe_path, ensure_dir

BASE_DIR = Path(__file__).resolve().parent
REPO_DIR = BASE_DIR.parent.parent
DATA_GLOB = REPO_DIR / "dataset" / "hai" / "hai-21.03" / "train*.csv.gz"
SPLIT_PATH = BASE_DIR / "feature_split.json"
OUT_STATS = BASE_DIR / "results" / "cont_stats.json"
OUT_VOCAB = BASE_DIR / "results" / "disc_vocab.json"


def main(max_rows: Optional[int] = None):
    split = load_split(safe_path(SPLIT_PATH))
    time_col = split.get("time_column", "time")
    cont_cols = [c for c in split["continuous"] if c != time_col]
    disc_cols = [c for c in split["discrete"] if not c.startswith("attack") and c != time_col]

    data_paths = sorted(Path(REPO_DIR / "dataset" / "hai" / "hai-21.03").glob("train*.csv.gz"))
    if not data_paths:
        raise SystemExit("no train files found under %s" % str(DATA_GLOB))
    data_paths = [safe_path(p) for p in data_paths]

    mean, std, vmin, vmax, int_like, max_decimals = compute_cont_stats(data_paths, cont_cols, max_rows=max_rows)
    vocab, top_token = build_disc_stats(data_paths, disc_cols, max_rows=max_rows)

    ensure_dir(OUT_STATS.parent)
    with open(safe_path(OUT_STATS), "w", encoding="utf-8") as f:
        json.dump(
            {
                "mean": mean,
                "std": std,
                "min": vmin,
                "max": vmax,
                "int_like": int_like,
                "max_decimals": max_decimals,
                "max_rows": max_rows,
            },
            f,
            indent=2,
        )

    with open(safe_path(OUT_VOCAB), "w", encoding="utf-8") as f:
        json.dump({"vocab": vocab, "top_token": top_token, "max_rows": max_rows}, f, indent=2)


if __name__ == "__main__":
    # Default: sample 50000 rows for speed. Set to None for full scan.
    main(max_rows=50000)