"""OpenAI embedding helper for associative memory tier.

Single public function: ``embed_text(text) -> list[float] | None``.
Returns None on any failure — callers must implement a keyword fallback.
Never raises; all exceptions are logged as warnings.
"""

from __future__ import annotations

import logging

from openai import AsyncOpenAI

logger = logging.getLogger(__name__)

_MAX_INPUT_CHARS = 8000
_EMBEDDING_MODEL = "text-embedding-3-small"


async def embed_text(text: str) -> list[float] | None:
    """Call OpenAI text-embedding-3-small. Return None on failure (caller falls back to keyword)."""
    try:
        client = AsyncOpenAI()
        truncated = text[:_MAX_INPUT_CHARS]
        response = await client.embeddings.create(
            input=truncated,
            model=_EMBEDDING_MODEL,
        )
        result: list[float] = response.data[0].embedding
        logger.debug("embeddings: embed_text dims=%d", len(result))
        return result
    except Exception as exc:
        logger.warning("embeddings: embed_text failed: %s", exc)
        return None