#!/usr/bin/env python3
"""Apply instruction strings into ArenaVlaSafety HDF5 files.

Input is a JSONL file whose each line contains at least:
  - path: path to HDF5 relative to --base-dir (or an absolute path)
  - instruction or instructions: text string, or a list of strings

For every HDF5, this script writes the instruction into all groups under
`data/<timestamp>/instruction`. If the dataset is missing, it will be created
as UTF-8 variable-length string. If it already exists (scalar or array), it is
overwritten with the provided text.

Example:
  python scripts/apply_instructions.py \
    --instructions /path/to/instructions.jsonl \
    --base-dir /mnt/nvme1/WS/czx/data/trainv0
"""

from __future__ import annotations

import argparse
import json
from pathlib import Path
from typing import Any, Optional

import h5py
import numpy as np


def _resolve_h5(base_dir: Path, file_path: str) -> Path:
    p = Path(file_path)
    if not p.is_absolute():
        p = base_dir / p
    return p.expanduser().resolve()


def _pick_instruction(obj: Any) -> Optional[str]:
    # Accept either `instruction` (str) or `instructions` (list[str]/str)
    if obj is None:
        return None
    if isinstance(obj, str):
        return obj.strip() or None
    if isinstance(obj, (list, tuple)):
        for item in obj:
            if isinstance(item, str) and item.strip():
                return item.strip()
        return None
    return None


def _write_instruction(h5_path: Path, text: str) -> None:
    text = str(text)
    with h5py.File(h5_path, "a") as f:
        data_group = f.get("data")
        if data_group is None:
            raise ValueError(f"{h5_path} missing 'data' group")
        # Use variable-length UTF-8 strings
        str_dtype = h5py.string_dtype(encoding="utf-8")
        for ts_key in list(data_group.keys()):
            grp = data_group[ts_key]
            ds = grp.get("instruction")
            if ds is None:
                ds = grp.create_dataset("instruction", shape=(), dtype=str_dtype)
                ds[...] = text
                continue
            # Scalar dataset
            if ds.shape == ():
                try:
                    ds[...] = text
                except TypeError:
                    # Recreate dataset with string dtype
                    del grp["instruction"]
                    ds = grp.create_dataset("instruction", shape=(), dtype=str_dtype)
                    ds[...] = text
            else:
                fill = np.empty(ds.shape, dtype=ds.dtype)
                try:
                    fill[...] = text
                except TypeError:
                    fill = np.empty(ds.shape, dtype=str)
                    fill[...] = text
                ds[...] = fill


def main() -> None:
    ap = argparse.ArgumentParser(description="Inject instruction text into HDF5 episodes")
    ap.add_argument("--instructions", required=True, help="Path to JSONL file")
    ap.add_argument("--base-dir", required=True, help="Base dir to resolve relative HDF5 paths")
    args = ap.parse_args()

    base_dir = Path(args.base_dir).expanduser().resolve()
    jsonl = Path(args.instructions).expanduser().resolve()
    if not jsonl.exists():
        raise FileNotFoundError(jsonl)

    updated = 0
    skipped = 0
    missing = 0
    with jsonl.open("r", encoding="utf-8") as fh:
        for line in fh:
            line = line.strip()
            if not line:
                continue
            try:
                rec = json.loads(line)
            except json.JSONDecodeError:
                print(f"[WARN] skip invalid JSON: {line[:80]}...")
                skipped += 1
                continue
            # Flexible field names for path
            path_field = rec.get("path") or rec.get("relpath") or rec.get("file") or rec.get("h5_path")
            if not path_field:
                print("[WARN] skip record without path")
                skipped += 1
                continue
            instr = (
                _pick_instruction(rec.get("instruction"))
                or _pick_instruction(rec.get("instructions"))
            )
            if not instr:
                print(f"[WARN] no instruction for {path_field}; skip")
                skipped += 1
                continue
            h5_path = _resolve_h5(base_dir, str(path_field))
            if not h5_path.exists():
                print(f"[WARN] missing file: {h5_path}")
                missing += 1
                continue
            try:
                _write_instruction(h5_path, instr)
                updated += 1
            except Exception as e:
                print(f"[ERROR] write failed for {h5_path}: {e}")
                skipped += 1
    print(f"Done. Updated={updated}, Missing={missing}, Skipped={skipped}")


if __name__ == "__main__":
    main()