#!/usr/bin/env python3
import argparse
from pathlib import Path
import json
from encryption_utils import derive_key, decrypt_text

def main():
    parser = argparse.ArgumentParser(description="Batch decrypt BCV3 JSONL")
    parser.add_argument("--input", required=True, help="Path to train.jsonl (or archived bcv3_encrypted.jsonl)")
    parser.add_argument("--key-file", required=True, help="Path to a text file containing passphrase")
    parser.add_argument("--output-dir", required=True, help="Directory to write per-sample JSON")
    parser.add_argument("--keep-encrypted", action="store_true", help="Keep encrypted fields in output")
    args = parser.parse_args()

    key_str = Path(args.key_file).read_text(encoding="utf-8").strip()
    key = derive_key(key_str)

    out_dir = Path(args.output_dir)
    out_dir.mkdir(parents=True, exist_ok=True)

    count = 0
    total = 0
    with Path(args.input).open("r", encoding="utf-8") as f:
        for line in f:
            if not line.strip():
                continue
            total += 1
            obj = json.loads(line)

            # Detect format: archived bcv3_encrypted.jsonl vs current train.jsonl
            if "encrypted_data" in obj:
                enc = obj.get("encrypted_data", {})
                question = decrypt_text(enc.get("question", {}), key)
                answer = decrypt_text(enc.get("answer", {}), key)
            elif "encrypted_question" in obj:
                enc_q = json.loads(obj.get("encrypted_question", "{}"))
                enc_a = json.loads(obj.get("encrypted_answer", "{}"))
                question = decrypt_text(enc_q, key)
                answer = decrypt_text(enc_a, key)
            else:
                print(f"Warning: Unrecognized format in record {total}, skipping...")
                continue

            out_obj = obj.copy()
            out_obj["question"] = question
            out_obj["answer"] = answer

            if not args.keep_encrypted:
                out_obj.pop("encrypted_data", None)
                out_obj.pop("encrypted_question", None)
                out_obj.pop("encrypted_answer", None)
                out_obj.pop("trajectory", None)

            out_path = out_dir / f"{obj.get('id')}.json"
            out_path.write_text(json.dumps(out_obj, ensure_ascii=False, indent=2), encoding="utf-8")
            count += 1

    print(f"Decrypted {count}/{total} samples and wrote to {out_dir}")

if __name__ == "__main__":
    main()