# llm_adapters.py
# -*- coding: utf-8 -*-
import logging
from typing import Optional
from langchain_openai import ChatOpenAI

def ensure_openai_base_url_has_v1(url: str) -> str:
    import re
    url = url.strip()
    if not url:
        return url
    if not re.search(r'/v\d+$', url):
        if '/v1' not in url:
            url = url.rstrip('/') + '/v1'
    return url

class BaseLLMAdapter:
    """
    统一的 LLM 接口基类，为不同后端（OpenAI、Ollama、ML Studio 等）提供一致的方法签名。
    """
    def invoke(self, prompt: str) -> str:
        raise NotImplementedError("Subclasses must implement .invoke(prompt) method.")

class DeepSeekAdapter(BaseLLMAdapter):
    """
    适配官方/OpenAI兼容接口（使用 langchain.ChatOpenAI）
    """
    def __init__(self, api_key: str, base_url: str, model_name: str, max_tokens: int, temperature: float = 0.7, timeout: Optional[int] = 600):
        self.base_url = ensure_openai_base_url_has_v1(base_url)
        self.api_key = api_key
        self.model_name = model_name
        self.max_tokens = max_tokens
        self.temperature = temperature
        self.timeout = timeout

        self._client = ChatOpenAI(
            model=self.model_name,
            api_key=self.api_key,
            base_url=self.base_url,
            max_tokens=self.max_tokens,
            temperature=self.temperature,
            timeout=self.timeout
        )

    def invoke(self, prompt: str) -> str:
        response = self._client.invoke(prompt)
        if not response:
            logging.warning("No response from DeepSeekAdapter.")
            return ""
        return response.content

class OpenAIAdapter(BaseLLMAdapter):
    """
    适配官方/OpenAI兼容接口（使用 langchain.ChatOpenAI）
    """
    def __init__(self, api_key: str, base_url: str, model_name: str, max_tokens: int, temperature: float = 0.7, timeout: Optional[int] = 600):
        self.base_url = ensure_openai_base_url_has_v1(base_url)
        self.api_key = api_key
        self.model_name = model_name
        self.max_tokens = max_tokens
        self.temperature = temperature
        self.timeout = timeout

        self._client = ChatOpenAI(
            model=self.model_name,
            api_key=self.api_key,
            base_url=self.base_url,
            max_tokens=self.max_tokens,
            temperature=self.temperature,
            timeout=self.timeout
        )

    def invoke(self, prompt: str) -> str:
        response = self._client.invoke(prompt)
        if not response:
            logging.warning("No response from OpenAIAdapter.")
            return ""
        return response.content

class OllamaAdapter(BaseLLMAdapter):
    """
    Ollama 同样有一个 OpenAI-like /v1/chat 接口，可直接使用 ChatOpenAI。
    但是通常 Ollama 默认本地服务在 http://localhost:11434，如果符合OpenAI风格即可直接传参。
    """
    def __init__(self, api_key: str, base_url: str, model_name: str, max_tokens: int, temperature: float = 0.7, timeout: Optional[int] = 600):
        self.base_url = ensure_openai_base_url_has_v1(base_url)
        self.api_key = api_key
        self.model_name = model_name
        self.max_tokens = max_tokens
        self.temperature = temperature
        self.timeout = timeout

        self._client = ChatOpenAI(
            model=self.model_name,
            api_key=self.api_key,
            base_url=self.base_url,
            max_tokens=self.max_tokens,
            temperature=self.temperature,
            timeout=self.timeout
        )

    def invoke(self, prompt: str) -> str:
        response = self._client.invoke(prompt)
        if not response:
            logging.warning("No response from OllamaAdapter.")
            return ""
        return response.content

class MLStudioAdapter(BaseLLMAdapter):
    def __init__(self, api_key: str, base_url: str, model_name: str, max_tokens: int, temperature: float = 0.7, timeout: Optional[int] = 600):
        self.base_url = ensure_openai_base_url_has_v1(base_url)
        self.api_key = api_key
        self.model_name = model_name
        self.max_tokens = max_tokens
        self.temperature = temperature
        self.timeout = timeout

        self._client = ChatOpenAI(
            model=self.model_name,
            api_key=self.api_key,
            base_url=self.base_url,
            max_tokens=self.max_tokens,
            temperature=self.temperature,
            timeout=self.timeout
        )

    def invoke(self, prompt: str) -> str:
        response = self._client.invoke(prompt)
        if not response:
            logging.warning("No response from MLStudioAdapter.")
            return ""
        return response.content

def create_llm_adapter(
    interface_format: str,
    base_url: str,
    model_name: str,
    api_key: str,
    temperature: float,
    max_tokens: int,
    timeout: int
) -> BaseLLMAdapter:
    """
    工厂函数：根据 interface_format 返回不同的适配器实例。
    """
    if interface_format.lower() == "deepseek":
        return DeepSeekAdapter(api_key, base_url, model_name, max_tokens, temperature, timeout)
    elif interface_format.lower() == "openai":
        return OpenAIAdapter(api_key, base_url, model_name, max_tokens, temperature, timeout)
    elif interface_format.lower() == "ollama":
        return OllamaAdapter(api_key, base_url, model_name, max_tokens, temperature, timeout)
    elif interface_format.lower() == "ml studio":
        return MLStudioAdapter(api_key, base_url, model_name, max_tokens, temperature, timeout)
    else:
        raise ValueError(f"Unknown interface_format: {interface_format}")