"""LLM 客户端基类

定义统一的 LLM 接口
"""

from __future__ import annotations

from abc import ABC, abstractmethod
from dataclasses import dataclass, field
from enum import Enum
from typing import Any, AsyncIterator


class Provider(str, Enum):
    """LLM 提供商"""

    ANTHROPIC = "anthropic"  # Claude
    OPENAI = "openai"  # GPT
    DEEPSEEK = "deepseek"  # DeepSeek
    ZHIPU = "zhipu"  # 智谱 GLM
    MINIMAX = "minimax"  # MiniMax
    MOONSHOT = "moonshot"  # Kimi
    GEMINI = "gemini"  # Google Gemini

    @property
    def is_overseas(self) -> bool:
        """是否为境外服务（需要代理）"""
        return self in {Provider.ANTHROPIC, Provider.OPENAI, Provider.GEMINI}

    @property
    def display_name(self) -> str:
        """显示名称"""
        names = {
            Provider.ANTHROPIC: "Claude (Anthropic)",
            Provider.OPENAI: "GPT (OpenAI)",
            Provider.DEEPSEEK: "DeepSeek",
            Provider.ZHIPU: "GLM (智谱)",
            Provider.MINIMAX: "MiniMax",
            Provider.MOONSHOT: "Kimi (Moonshot)",
            Provider.GEMINI: "Gemini (Google)",
        }
        return names.get(self, self.value)


@dataclass
class Message:
    """消息"""

    role: str  # "user", "assistant", "system"
    content: str
    name: str | None = None
    tool_calls: list[ToolCall] | None = None
    tool_call_id: str | None = None  # 用于 tool 结果消息


@dataclass
class ToolCall:
    """工具调用"""

    id: str
    name: str
    arguments: dict[str, Any] = field(default_factory=dict)


@dataclass
class ToolDefinition:
    """工具定义"""

    name: str
    description: str
    parameters: dict[str, Any] = field(default_factory=dict)


@dataclass
class LLMResponse:
    """LLM 响应"""

    content: str
    model: str
    provider: Provider
    tool_calls: list[ToolCall] | None = None
    finish_reason: str = "stop"
    usage: dict[str, int] = field(default_factory=dict)
    raw_response: Any = None


@dataclass
class StreamChunk:
    """流式响应块"""

    content: str
    is_final: bool = False
    tool_calls: list[ToolCall] | None = None
    usage: dict[str, int] | None = None


class BaseLLMClient(ABC):
    """LLM 客户端基类"""

    provider: Provider
    default_model: str

    def __init__(
        self,
        api_key: str,
        base_url: str | None = None,
        proxy: str | None = None,
        timeout: float = 60.0,
        max_retries: int = 3,
    ) -> None:
        """初始化客户端

        Args:
            api_key: API 密钥
            base_url: 自定义 API 地址
            proxy: 代理地址（境外服务使用）
            timeout: 请求超时（秒）
            max_retries: 最大重试次数
        """
        self.api_key = api_key
        self.base_url = base_url
        self.proxy = proxy
        self.timeout = timeout
        self.max_retries = max_retries

    @abstractmethod
    async def chat(
        self,
        messages: list[Message],
        model: str | None = None,
        system: str | None = None,
        max_tokens: int = 4096,
        temperature: float = 0.7,
        tools: list[ToolDefinition] | None = None,
        **kwargs: Any,
    ) -> LLMResponse:
        """发送聊天请求

        Args:
            messages: 消息列表
            model: 模型名称
            system: 系统提示词
            max_tokens: 最大输出 token
            temperature: 温度参数
            tools: 工具定义列表
            **kwargs: 其他参数

        Returns:
            LLM 响应
        """
        pass

    @abstractmethod
    async def chat_stream(
        self,
        messages: list[Message],
        model: str | None = None,
        system: str | None = None,
        max_tokens: int = 4096,
        temperature: float = 0.7,
        tools: list[ToolDefinition] | None = None,
        **kwargs: Any,
    ) -> AsyncIterator[StreamChunk]:
        """流式聊天

        Args:
            messages: 消息列表
            model: 模型名称
            system: 系统提示词
            max_tokens: 最大输出 token
            temperature: 温度参数
            tools: 工具定义列表
            **kwargs: 其他参数

        Yields:
            流式响应块
        """
        pass

    def _convert_messages(self, messages: list[Message]) -> list[dict[str, Any]]:
        """转换消息格式为 API 格式（子类可覆盖）"""
        result = []
        for msg in messages:
            item: dict[str, Any] = {
                "role": msg.role,
                "content": msg.content,
            }
            if msg.name:
                item["name"] = msg.name
            if msg.tool_call_id:
                item["tool_call_id"] = msg.tool_call_id
            result.append(item)
        return result

    def _convert_tools(self, tools: list[ToolDefinition]) -> list[dict[str, Any]]:
        """转换工具定义格式（子类可覆盖）"""
        return [
            {
                "type": "function",
                "function": {
                    "name": tool.name,
                    "description": tool.description,
                    "parameters": tool.parameters,
                },
            }
            for tool in tools
        ]

    async def close(self) -> None:
        """关闭客户端"""
        pass

    def get_available_models(self) -> list[str]:
        """获取可用模型列表"""
        return [self.default_model]