import os
from typing import List, Dict, Any
from datetime import datetime

import numpy as np
import pyarrow as pa
import pyarrow.parquet as pq

from config import EMB_DIR, MANIFEST_PATH

def _ensure_float32(vectors: List[List[float]]) -> List[List[float]]:
    return [np.asarray(v, dtype=np.float32).tolist() for v in vectors]

def write_parquet(
    rows: List[Dict[str, Any]],
    parquet_out_path: str
) -> None:
    """Write rows with schema to Parquet (ZSTD)."""
    table = pa.Table.from_pylist(rows)
    pq.write_table(table, parquet_out_path, compression="zstd" )
    print(f"[INFO] Parquet saved: {parquet_out_path}")

def append_manifest(entries: List[Dict[str, Any]]) -> None:
    os.makedirs(os.path.dirname(MANIFEST_PATH), exist_ok=True)
    with open(MANIFEST_PATH, "a", encoding="utf-8") as f:
        for e in entries:
            f.write(__to_jsonl_line(e) + "\n")
    print(f"[INFO] Manifest appended: {MANIFEST_PATH}")

def __to_jsonl_line(obj: Dict[str, Any]) -> str:
    # Basic compact JSON; avoid pretty for smaller size
    import json
    return json.dumps(obj, ensure_ascii=False, separators=(",", ":"))