# import re
import ast
from typing import Dict, Any, Optional, List, Union

from contextlib import asynccontextmanager
import asyncio


class PromptContext:
    def __init__(self):
        self._context_prompts: Dict[str, Dict[str, "Prompt"]] = {}
        self._current_context: Optional[str] = None
        self._context_lock = asyncio.Lock()  # 添加异步锁

    @asynccontextmanager
    async def async_scope(self, context_id: str):
        """创建一个异步的临时提示模板作用域"""
        async with self._context_lock:
            if context_id not in self._context_prompts:
                self._context_prompts[context_id] = {}

            previous_context = self._current_context
            self._current_context = context_id
        try:
            yield self
        finally:
            async with self._context_lock:
                self._current_context = previous_context

    async def get_prompt_async(self, name: str) -> Optional["Prompt"]:
        """异步获取当前作用域中的提示模板"""
        async with self._context_lock:
            if self._current_context and name in self._context_prompts[self._current_context]:
                return self._context_prompts[self._current_context][name]
            return None

    async def register_async(self, prompt: "Prompt", context_id: Optional[str] = None) -> None:
        """异步注册提示模板到指定作用域"""
        async with self._context_lock:
            target_context = context_id or self._current_context
            if target_context:
                self._context_prompts.setdefault(target_context, {})[prompt.name] = prompt


class PromptManager:
    def __init__(self):
        self._prompts = {}
        self._counter = 0
        self._context = PromptContext()
        self._lock = asyncio.Lock()

    @asynccontextmanager
    async def async_message_scope(self, message_id: str):
        """为消息处理创建异步临时作用域"""
        async with self._context.async_scope(message_id):
            yield self

    async def get_prompt_async(self, name: str) -> "Prompt":
        # 首先尝试从当前上下文获取
        context_prompt = await self._context.get_prompt_async(name)
        if context_prompt is not None:
            return context_prompt
        # 如果上下文中不存在，则使用全局提示模板
        async with self._lock:
            if name not in self._prompts:
                raise KeyError(f"Prompt '{name}' not found")
            return self._prompts[name]

    def generate_name(self, template: str) -> str:
        """为未命名的prompt生成名称"""
        self._counter += 1
        return f"prompt_{self._counter}"

    def register(self, prompt: "Prompt") -> None:
        """注册一个prompt"""
        if not prompt.name:
            prompt.name = self.generate_name(prompt.template)
        self._prompts[prompt.name] = prompt

    def add_prompt(self, name: str, fstr: str) -> "Prompt":
        prompt = Prompt(fstr, name=name)
        self._prompts[prompt.name] = prompt
        return prompt

    async def format_prompt(self, name: str, **kwargs) -> str:
        prompt = await self.get_prompt_async(name)
        return prompt.format(**kwargs)


# 全局单例
global_prompt_manager = PromptManager()


class Prompt(str):
    def __new__(cls, fstr: str, name: Optional[str] = None, args: Union[List[Any], tuple[Any, ...]] = None, **kwargs):
        # 如果传入的是元组，转换为列表
        if isinstance(args, tuple):
            args = list(args)

        # 解析模板
        tree = ast.parse(f"f'''{fstr}'''", mode="eval")
        template_args = set()
        for node in ast.walk(tree):
            if isinstance(node, ast.FormattedValue):
                expr = ast.get_source_segment(fstr, node.value)
                if expr:
                    template_args.add(expr)

        # 如果提供了初始参数，立即格式化
        if kwargs or args:
            formatted = cls._format_template(fstr, args=args, kwargs=kwargs)
            obj = super().__new__(cls, formatted)
        else:
            obj = super().__new__(cls, "")

        obj.template = fstr
        obj.name = name
        obj.args = template_args
        obj._args = args or []
        obj._kwargs = kwargs

        # 修改自动注册逻辑
        if global_prompt_manager._context._current_context:
            # 如果存在当前上下文，则注册到上下文中
            # asyncio.create_task(global_prompt_manager._context.register_async(obj))
            pass
        else:
            # 否则注册到全局管理器
            global_prompt_manager.register(obj)
        return obj

    @classmethod
    async def create_async(
        cls, fstr: str, name: Optional[str] = None, args: Union[List[Any], tuple[Any, ...]] = None, **kwargs
    ):
        """异步创建Prompt实例"""
        prompt = cls(fstr, name, args, **kwargs)
        if global_prompt_manager._context._current_context:
            await global_prompt_manager._context.register_async(prompt)
        return prompt

    @classmethod
    def _format_template(cls, template: str, args: List[Any] = None, kwargs: Dict[str, Any] = None) -> str:
        fmt_str = f"f'''{template}'''"
        tree = ast.parse(fmt_str, mode="eval")
        template_args = []
        for node in ast.walk(tree):
            if isinstance(node, ast.FormattedValue):
                expr = ast.get_source_segment(fmt_str, node.value)
                if expr and expr not in template_args:
                    template_args.append(expr)
        formatted_args = {}
        formatted_kwargs = {}

        # 处理位置参数
        if args:
            for i in range(len(args)):
                arg = args[i]
                if isinstance(arg, Prompt):
                    formatted_args[template_args[i]] = arg.format(**kwargs)
                else:
                    formatted_args[template_args[i]] = arg

        # 处理关键字参数
        if kwargs:
            for key, value in kwargs.items():
                if isinstance(value, Prompt):
                    remaining_kwargs = {k: v for k, v in kwargs.items() if k != key}
                    formatted_kwargs[key] = value.format(**remaining_kwargs)
                else:
                    formatted_kwargs[key] = value

        try:
            # 先用位置参数格式化

            if args:
                template = template.format(**formatted_args)
            # 再用关键字参数格式化
            if kwargs:
                template = template.format(**formatted_kwargs)
            return template
        except (IndexError, KeyError) as e:
            raise ValueError(f"格式化模板失败: {template}, args={formatted_args}, kwargs={formatted_kwargs}") from e

    def format(self, *args, **kwargs) -> "Prompt":
        """支持位置参数和关键字参数的格式化，使用"""
        ret = type(self)(
            self.template, self.name, args=list(args) if args else self._args, **kwargs if kwargs else self._kwargs
        )
        # print(f"prompt build result: {ret}  name: {ret.name} ")
        return ret

    def __str__(self) -> str:
        if self._kwargs or self._args:
            return super().__str__()
        return self.template

    def __repr__(self) -> str:
        return f"Prompt(template='{self.template}', name='{self.name}')"