import json
from pathlib import Path
from typing import Any

import requests


class LLMConfigManager:
    def __init__(self, config_path: str):
        self.config_path = Path(config_path)

    def load(self) -> dict:
        if not self.config_path.exists():
            return {}
        with self.config_path.open("r", encoding="utf-8-sig") as file:
            return json.load(file)


def _join_url(base_url: str, path: str) -> str:
    return f"{base_url.rstrip('/')}/{path.lstrip('/')}"


def _timeout(config: dict) -> int:
    section = config.get("request", {}) if isinstance(config, dict) else {}
    try:
        return int(section.get("timeout_seconds", 45))
    except Exception:
        return 45


def _extract_openai_text(payload: Any) -> str:
    if isinstance(payload, dict):
        choices = payload.get("choices")
        if isinstance(choices, list) and choices:
            msg = choices[0].get("message") if isinstance(choices[0], dict) else {}
            if isinstance(msg, dict) and msg.get("content"):
                return str(msg["content"])
        if payload.get("answer"):
            return str(payload["answer"])
        if payload.get("data"):
            return json.dumps(payload["data"], ensure_ascii=False)
    return json.dumps(payload, ensure_ascii=False) if isinstance(payload, (dict, list)) else str(payload)


def ask_fastgpt(config: dict, prompt: str, context: str = "", custom_uid: str = "") -> dict:
    section = config.get("fastgpt", {})
    base_url = section.get("base_url", "").strip()
    api_key = section.get("api_key", "").strip()
    chat_id = str(section.get("chat_id", "111"))
    model = section.get("model", "")
    timeout = _timeout(config)

    if not base_url or not api_key:
        return {"ok": False, "message": "FastGPT 未配置 base_url 或 api_key"}

    url = _join_url(base_url, "/v1/chat/completions")
    headers = {
        "Authorization": f"Bearer {api_key}",
        "Content-Type": "application/json",
    }

    content = prompt if not context else f"请基于以下本地知识库内容回答。\n\n知识库:\n{context}\n\n问题: {prompt}"
    messages = []
    system_prompt = section.get("system_prompt")
    if system_prompt:
        messages.append({"role": "system", "content": system_prompt})
    messages.append({"role": "user", "content": content})

    use_custom_uid = custom_uid or section.get("custom_uid", "")
    payload = {
        "chatId": chat_id,
        "stream": False,
        "detail": False,
        "messages": messages,
    }
    if model:
        payload["model"] = model
    if use_custom_uid:
        payload["customUid"] = use_custom_uid

    try:
        response = requests.post(url, headers=headers, json=payload, timeout=timeout, allow_redirects=True)
        if response.status_code >= 400:
            return {
                "ok": False,
                "message": f"FastGPT 调用失败: HTTP {response.status_code}",
                "detail": response.text,
            }

        data = response.json()
        return {
            "ok": True,
            "provider": "fastgpt",
            "raw": data,
            "answer": _extract_openai_text(data),
        }
    except Exception as exc:
        return {
            "ok": False,
            "message": "FastGPT 请求异常",
            "detail": str(exc),
        }


def ask_dify(config: dict, prompt: str, context: str = "", user: str = "anonymous") -> dict:
    section = config.get("dify", {})
    base_url = section.get("base_url", "").strip()
    api_key = section.get("api_key", "").strip()
    timeout = _timeout(config)

    if not base_url or not api_key:
        return {"ok": False, "message": "Dify 未配置 base_url 或 api_key"}

    url = _join_url(base_url, "/v1/chat-messages")
    headers = {
        "Authorization": f"Bearer {api_key}",
        "Content-Type": "application/json",
    }

    query = prompt if not context else f"知识库上下文:\n{context}\n\n用户问题:\n{prompt}"
    payload = {
        "inputs": {},
        "query": query,
        "response_mode": "blocking",
        "conversation_id": "",
        "user": user,
    }

    try:
        response = requests.post(url, headers=headers, json=payload, timeout=timeout, allow_redirects=True)
        if response.status_code >= 400:
            return {
                "ok": False,
                "message": f"Dify 调用失败: HTTP {response.status_code}",
                "detail": response.text,
            }

        data = response.json()
        answer = data.get("answer") or _extract_openai_text(data)
        return {
            "ok": True,
            "provider": "dify",
            "raw": data,
            "answer": answer,
        }
    except Exception as exc:
        return {
            "ok": False,
            "message": "Dify 请求异常",
            "detail": str(exc),
        }