lib/openai_client.py

import os
import json
from typing import List, Dict
from openai import OpenAI

_EMBED_MODEL = os.getenv("EMBED_MODEL", "text-embedding-3-large")
_CHAT_MODEL = os.getenv("CHAT_MODEL", "gpt-4o-mini")

def get_client() -> OpenAI:
    # OPENAI_API_KEY は Spaces の Secrets に設定してください
    if not os.getenv("OPENAI_API_KEY"):
        raise RuntimeError("OPENAI_API_KEY が未設定です（Settings → Secrets に追加してください）。")
    return OpenAI()

def embed_texts(texts: List[str], batch_size: int = 128) -> List[List[float]]:
    client = get_client()
    out: List[List[float]] = []
    for i in range(0, len(texts), batch_size):
        batch = texts[i:i+batch_size]
        resp = client.embeddings.create(model=_EMBED_MODEL, input=batch)
        out.extend([d.embedding for d in resp.data])
    return out

def summarize_cluster(samples: List[str], output_lang: str = "ja") -> Dict:
    """
    samples を読んで、構造化要約(JSON) + 感情比率を返す。
    output_lang: 'ja'|'en'|'auto'
    """
    client = get_client()
    if output_lang == "ja":
        lang_inst = "回答は必ず日本語で。"
    elif output_lang == "en":
        lang_inst = "Respond in English."
    else:
        lang_inst = "Respond in the most appropriate language for the comments."

    prompt = f"""
You are an insightful product analyst. Read user comments and output a concise JSON with:
- title: short cluster title
- overview: 2-3 sentences
- actions: 2-5 actionable suggestions (array of strings)
- sentiment: proportions of positive/neutral/negative (each 0-1 float; sum≈1)

{lang_inst}

Comments:
{chr(10).join(f"- {s}" for s in samples[:30])}

Return ONLY strict JSON with keys: title, overview, actions, sentiment.
    """.strip()

    try:
        resp = client.chat.completions.create(
            model=_CHAT_MODEL,
            messages=[{"role": "user", "content": prompt}],
            temperature=0.2,
            response_format={"type": "json_object"},
        )
        return json.loads(resp.choices[0].message.content)
    except Exception:
        # フォールバック
        return {
            "title": "クラスタ",
            "overview": "要約に失敗しました。",
            "actions": [],
            "sentiment": {"positive": 0.33, "neutral": 0.34, "negative": 0.33},
        }