import httpx
from openai import AsyncOpenAI

from services.runtime_settings import get_ai_settings

# 按 (base_url, api_key) 缓存客户端：聊天/视觉/语音可能指向不同网关与密钥，
# 各自一个 pair，最多累积 3 个，有界。配置变更（settings PUT 会 invalidate
# runtime_settings 缓存）后，新的 pair 会自然生成新客户端；旧的留存无副作用。
_client_cache: dict[tuple[str, str], AsyncOpenAI] = {}
_http_client_cache: dict[tuple[str, str], httpx.AsyncClient] = {}


def _get_client(base_url: str, api_key: str) -> AsyncOpenAI:
    cache_key = (base_url or "", api_key or "")
    if cache_key not in _client_cache:
        http_client = httpx.AsyncClient(timeout=httpx.Timeout(600.0, connect=30.0))
        _http_client_cache[cache_key] = http_client
        _client_cache[cache_key] = AsyncOpenAI(
            api_key=api_key or "missing",
            base_url=base_url or None,
            http_client=http_client,
        )
    return _client_cache[cache_key]


async def get_openai_client() -> tuple[AsyncOpenAI, dict]:
    """聊天调用方（话题/报告/总结/对话）复用：用全局 ai_base_url / ai_api_key。"""
    settings = await get_ai_settings()
    client = _get_client(
        settings.get("ai_base_url") or "",
        settings.get("ai_api_key") or "",
    )
    return client, settings


async def get_client_for(purpose: str) -> tuple[AsyncOpenAI, dict]:
    """按用途取客户端：purpose 为 'voice' / 'vision'。

    优先用 {purpose}_base_url / {purpose}_api_key，为空则回退到全局
    ai_base_url / ai_api_key（单网关场景无需重复配置）。
    """
    settings = await get_ai_settings()
    base_url = settings.get(f"{purpose}_base_url") or settings.get("ai_base_url") or ""
    api_key = settings.get(f"{purpose}_api_key") or settings.get("ai_api_key") or ""
    client = _get_client(base_url, api_key)
    return client, settings