"""Ollama 客户端

通过 Ollama HTTP API 调用本地模型进行文本生成。
"""

import httpx
import structlog

from app.config import settings

logger = structlog.get_logger()


class OllamaClient:
    """Ollama HTTP API 客户端"""

    def __init__(
        self,
        base_url: str | None = None,
        model: str | None = None,
        timeout: float = 120.0,
    ) -> None:
        self.base_url = (base_url or settings.ollama_base_url).rstrip("/")
        self.model = model or settings.ollama_model
        self.timeout = timeout

    async def generate(self, prompt: str, json_mode: bool = False) -> str:
        """调用 Ollama 生成文本

        Args:
            prompt: 输入提示词
            json_mode: 为 True 时启用 Ollama 原生 JSON 约束输出（payload 加 format: json）

        Returns:
            生成的文本内容
        """
        url = f"{self.base_url}/api/generate"
        payload = {
            "model": self.model,
            "prompt": prompt,
            "stream": False,
        }
        if json_mode:
            payload["format"] = "json"

        async with httpx.AsyncClient(timeout=self.timeout) as client:
            resp = await client.post(url, json=payload)
            resp.raise_for_status()
            data = resp.json()

        result = data.get("response", "")
        logger.debug("Ollama 生成完成", model=self.model, output_length=len(result))
        return result

    async def is_available(self) -> bool:
        """检查 Ollama 服务是否可用"""
        try:
            async with httpx.AsyncClient(timeout=5.0) as client:
                resp = await client.get(f"{self.base_url}/api/tags")
                return resp.status_code == 200
        except httpx.HTTPError:
            return False