"""
OpenAI API 客户端封装（同步/异步）

提供与 :mod:`llm.deepseek_client` 同形态的接口，便于在需要时切换 LLM 路由。
"""

from __future__ import annotations

import json
import logging
import os
from dataclasses import dataclass
from typing import Any, Dict, Iterator, List, Optional

from openai import AsyncOpenAI, OpenAI  # type: ignore[import-not-found]
from openai.types.chat import (  # type: ignore[import-not-found]
    ChatCompletion,
    ChatCompletionMessage,
)

logger = logging.getLogger(__name__)


@dataclass
class OpenAIConfig:
    """OpenAI API 配置（支持 OpenAI 兼容网关）。"""

    api_key: str
    base_url: str = "https://api.openai.com/v1"
    model_name: str = "gpt-4o-mini"
    temperature: float = 0.3
    max_tokens: int = 4096
    top_p: float = 0.9
    frequency_penalty: float = 0.0
    presence_penalty: float = 0.0
    timeout: float = 60.0
    extra_headers: Optional[Dict[str, str]] = None


class OpenAIClient:
    """
    OpenAI API 客户端（同步）。

    说明：本项目其他模块仅要求具备 ``chat`` / ``chat_with_json`` 方法；
    这里额外提供若干便捷方法，与 DeepSeekClient 对齐，便于复用同一套 prompt。
    """

    def __init__(self, config: OpenAIConfig):
        self.config = config
        self.client = OpenAI(
            api_key=config.api_key,
            base_url=config.base_url,
            timeout=config.timeout,
        )
        logger.info(
            "[OK] OpenAIClient初始化: model=%s, base_url=%s",
            config.model_name,
            config.base_url,
        )

    def chat(self, messages: List[Dict[str, str]], **kwargs) -> ChatCompletionMessage:
        max_tokens = kwargs.get("max_tokens", self.config.max_tokens)
        max_completion_tokens = kwargs.get("max_completion_tokens", None)

        params: Dict[str, Any] = {
            "model": self.config.model_name,
            "messages": messages,
            "temperature": kwargs.get("temperature", self.config.temperature),
            "top_p": kwargs.get("top_p", self.config.top_p),
            "frequency_penalty": kwargs.get(
                "frequency_penalty", self.config.frequency_penalty
            ),
            "presence_penalty": kwargs.get(
                "presence_penalty", self.config.presence_penalty
            ),
            "timeout": kwargs.get("timeout", self.config.timeout),
        }

        # 兼容不同模型/网关：
        # - 传统 Chat Completions 使用 max_tokens
        # - 部分新模型（如 gpt-5.*）要求 max_completion_tokens
        if max_completion_tokens is not None:
            params["max_completion_tokens"] = max_completion_tokens
        else:
            params["max_tokens"] = max_tokens

        if self.config.extra_headers:
            params["extra_headers"] = self.config.extra_headers

        try:
            response: ChatCompletion = self.client.chat.completions.create(**params)
            message = response.choices[0].message
            usage = response.usage
            if usage is not None:
                logger.debug(
                    "OpenAI调用完成: prompt_tokens=%s, completion_tokens=%s, total_tokens=%s",
                    usage.prompt_tokens,
                    usage.completion_tokens,
                    usage.total_tokens,
                )
            return message
        except Exception as e:
            # 自动兼容：若网关提示 max_tokens 不支持，则改用 max_completion_tokens 重试一次
            msg = str(e)
            if (
                "Unsupported parameter" in msg
                and "max_tokens" in msg
                and "max_completion_tokens" in msg
                and "max_completion_tokens" not in params
            ):
                params.pop("max_tokens", None)
                params["max_completion_tokens"] = max_tokens
                try:
                    response = self.client.chat.completions.create(**params)
                    return response.choices[0].message
                except Exception:
                    pass

            logger.error("OpenAI API调用失败: %s", e)
            raise

    def chat_stream(
        self,
        messages: List[Dict[str, str]],
        **kwargs: Any,
    ) -> Iterator[str]:
        """流式聊天：按 completion 增量产出文本片段（与 chat 同参，固定 stream=True）。"""
        max_tokens = kwargs.get("max_tokens", self.config.max_tokens)
        max_completion_tokens = kwargs.get("max_completion_tokens", None)

        params: Dict[str, Any] = {
            "model": self.config.model_name,
            "messages": messages,
            "temperature": kwargs.get("temperature", self.config.temperature),
            "top_p": kwargs.get("top_p", self.config.top_p),
            "frequency_penalty": kwargs.get(
                "frequency_penalty", self.config.frequency_penalty
            ),
            "presence_penalty": kwargs.get(
                "presence_penalty", self.config.presence_penalty
            ),
            "stream": True,
            "timeout": kwargs.get("timeout", self.config.timeout),
        }
        if max_completion_tokens is not None:
            params["max_completion_tokens"] = max_completion_tokens
        else:
            params["max_tokens"] = max_tokens

        if self.config.extra_headers:
            params["extra_headers"] = self.config.extra_headers

        try:
            stream = self.client.chat.completions.create(**params)
            for chunk in stream:
                if not chunk.choices:
                    continue
                delta = chunk.choices[0].delta
                if delta and getattr(delta, "content", None):
                    yield delta.content
        except Exception as e:
            msg = str(e)
            if (
                "Unsupported parameter" in msg
                and "max_tokens" in msg
                and "max_completion_tokens" in msg
                and "max_completion_tokens" not in params
            ):
                params.pop("max_tokens", None)
                params["max_completion_tokens"] = max_tokens
                try:
                    stream = self.client.chat.completions.create(**params)
                    for chunk in stream:
                        if not chunk.choices:
                            continue
                        delta = chunk.choices[0].delta
                        if delta and getattr(delta, "content", None):
                            yield delta.content
                    return
                except Exception:
                    pass
            logger.error("OpenAI API流式调用失败: %s", e)
            raise

    def chat_with_json(
        self, messages: List[Dict[str, str]], **kwargs
    ) -> Dict[str, Any]:
        message = self.chat(messages, **kwargs)
        content = (message.content or "").strip()

        try:
            if "```json" in content:
                start = content.find("```json") + 7
                end = content.find("```", start)
                content = content[start:end].strip()
            elif "```" in content:
                start = content.find("```") + 3
                end = content.find("```", start)
                content = content[start:end].strip()
            return json.loads(content)
        except json.JSONDecodeError as e:
            logger.warning("JSON解析失败，返回原始内容: %s", e)
            return {"_json_decode_failed": True, "raw_content": content}

    # ===== 便捷方法（与 DeepSeekClient 对齐）=====
    def generate_sql(
        self, prompt: str, schema: str, dialect: str = "tsql", **kwargs
    ) -> str:
        from config.prompts import SQL_GENERATOR_SYSTEM, SQL_GENERATOR_USER

        messages = [
            {"role": "system", "content": SQL_GENERATOR_SYSTEM},
            {
                "role": "user",
                "content": SQL_GENERATOR_USER.format(
                    schema=schema, question=prompt, dialect=dialect
                ),
            },
        ]

        kwargs.setdefault("temperature", 0.0)
        kwargs.setdefault("top_p", 1.0)
        response = self.chat(messages, **kwargs)
        content = (response.content or "").strip()

        if "```sql" in content:
            start = content.find("```sql") + 6
            end = content.find("```", start)
            content = content[start:end].strip()
        elif "```" in content:
            start = content.find("```") + 3
            end = content.find("```", start)
            content = content[start:end].strip()

        return content

    def validate_sql(self, sql: str, schema: str, **kwargs) -> Dict[str, Any]:
        from config.prompts import VALIDATOR_SYSTEM, VALIDATOR_USER

        messages = [
            {"role": "system", "content": VALIDATOR_SYSTEM},
            {"role": "user", "content": VALIDATOR_USER.format(sql=sql, schema=schema)},
        ]

        kwargs.setdefault("temperature", 0.0)
        kwargs.setdefault("top_p", 1.0)
        return self.chat_with_json(messages, **kwargs)

    def select_tables(
        self, question: str, table_list: str, **kwargs
    ) -> Dict[str, Any]:
        from config.prompts import SCHEMA_LINKER_SYSTEM, SCHEMA_LINKER_USER

        messages = [
            {"role": "system", "content": SCHEMA_LINKER_SYSTEM},
            {
                "role": "user",
                "content": SCHEMA_LINKER_USER.format(
                    question=question, table_list=table_list
                ),
            },
        ]

        kwargs.setdefault("temperature", 0.0)
        kwargs.setdefault("top_p", 1.0)
        return self.chat_with_json(messages, **kwargs)

    def normalize_nl_question_for_text2sql(self, question: str) -> str:
        from config.prompts import (
            CANONICALIZE_NL_FOR_TEXT2SQL_SYSTEM,
            CANONICALIZE_NL_FOR_TEXT2SQL_USER,
        )

        q = (question or "").strip()
        if not q:
            return ""
        messages = [
            {"role": "system", "content": CANONICALIZE_NL_FOR_TEXT2SQL_SYSTEM},
            {"role": "user", "content": CANONICALIZE_NL_FOR_TEXT2SQL_USER.format(question=q)},
        ]
        msg = self.chat(messages, temperature=0.0, top_p=1.0, max_completion_tokens=512)
        text = (msg.content or "").strip()
        line = text.splitlines()[0].strip() if text else ""
        return line.strip("「」\"'“”")

    def translate_nl_question_to_zh(self, question: str) -> str:
        return self.normalize_nl_question_for_text2sql(question)

    def empty_result_user_feedback(
        self,
        question: str,
        sql: str,
        schema: str,
        *,
        max_schema_chars: int = 8000,
        **kwargs: Any,
    ) -> str:
        from config.prompts import EMPTY_RESULT_FEEDBACK_SYSTEM, EMPTY_RESULT_FEEDBACK_USER

        schema_snip = (schema or "")[:max_schema_chars]
        messages = [
            {"role": "system", "content": EMPTY_RESULT_FEEDBACK_SYSTEM},
            {
                "role": "user",
                "content": EMPTY_RESULT_FEEDBACK_USER.format(
                    question=question or "(无)",
                    sql=sql,
                    schema=schema_snip,
                ),
            },
        ]
        msg = self.chat(messages, temperature=0.4, max_completion_tokens=512, **kwargs)
        return ((msg.content or "").strip())

    def sql_probe_success_delivery_message(
        self,
        question: str,
        sql: str,
        *,
        max_sql_chars: int = 4000,
        **kwargs: Any,
    ) -> str:
        from config.prompts import (
            SQL_PROBE_SUCCESS_DELIVERY_SYSTEM,
            SQL_PROBE_SUCCESS_DELIVERY_USER,
        )

        q = (question or "").strip() or "(无)"
        s = (sql or "").strip()
        if len(s) > max_sql_chars:
            s = s[: max_sql_chars - 20].rstrip() + "\n-- …(已截断)"

        messages = [
            {"role": "system", "content": SQL_PROBE_SUCCESS_DELIVERY_SYSTEM},
            {
                "role": "user",
                "content": SQL_PROBE_SUCCESS_DELIVERY_USER.format(question=q, sql=s),
            },
        ]
        kwargs.setdefault("temperature", 0.2)
        kwargs.setdefault("top_p", 1.0)
        kwargs.setdefault("max_completion_tokens", 320)
        msg = self.chat(messages, **kwargs)
        return (msg.content or "").strip()


class AsyncOpenAIClient:
    """OpenAI API 客户端（异步）。"""

    def __init__(self, config: OpenAIConfig):
        self.config = config
        self.client = AsyncOpenAI(
            api_key=config.api_key,
            base_url=config.base_url,
            timeout=config.timeout,
        )

    async def chat(self, messages: List[Dict[str, str]], **kwargs) -> ChatCompletionMessage:
        params: Dict[str, Any] = {
            "model": self.config.model_name,
            "messages": messages,
            "temperature": kwargs.get("temperature", self.config.temperature),
            "max_tokens": kwargs.get("max_tokens", self.config.max_tokens),
            "top_p": kwargs.get("top_p", self.config.top_p),
        }
        response = await self.client.chat.completions.create(**params)
        return response.choices[0].message


def create_openai_client(
    api_key: Optional[str] = None,
    **kwargs: Any,
) -> OpenAIClient:
    """
    便捷工厂：创建 OpenAIClient。

    读取环境变量：
    - OPENAI_API_KEY（必填）
    - OPENAI_BASE_URL（可选）
    - OPENAI_MODEL / OPENAI_CHAT_MODEL（可选）
    """
    if api_key is None:
        api_key = (os.getenv("OPENAI_API_KEY") or "").strip()
        if not api_key:
            raise ValueError("未提供 api_key 且环境变量 OPENAI_API_KEY 未设置。")

    base_url = (kwargs.pop("base_url", None) or os.getenv("OPENAI_BASE_URL") or "").strip()
    model_name = (
        kwargs.pop("model_name", None)
        or os.getenv("OPENAI_MODEL")
        or os.getenv("OPENAI_CHAT_MODEL")
        or ""
    ).strip()

    cfg_kwargs: Dict[str, Any] = dict(kwargs)
    if base_url:
        cfg_kwargs["base_url"] = base_url
    if model_name:
        cfg_kwargs["model_name"] = model_name

    config = OpenAIConfig(api_key=api_key, **cfg_kwargs)
    return OpenAIClient(config)