"""Provider 自动发现 + 注册表"""

from __future__ import annotations

import importlib
import pkgutil
from pathlib import Path
from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from app.providers.base import BaseProvider, Capability


class ProviderRegistry:
    """全局 Provider 注册表，启动时自动扫描 providers/ 目录"""

    _providers: dict[str, "BaseProvider"] = {}

    @classmethod
    def auto_discover(cls):
        """扫描当前包下所有模块，注册 BaseProvider 子类实例"""
        from app.providers.base import BaseProvider as _Base

        package_dir = Path(__file__).parent
        for info in pkgutil.iter_modules([str(package_dir)]):
            if info.name in ("base", "__init__"):
                continue
            mod = importlib.import_module(f"app.providers.{info.name}")
            for attr_name in dir(mod):
                attr = getattr(mod, attr_name)
                if (
                    isinstance(attr, type)
                    and issubclass(attr, _Base)
                    and attr is not _Base
                    and getattr(attr, "name", "")
                ):
                    instance = attr()
                    cls._providers[instance.name] = instance

    @classmethod
    def get(cls, name: str) -> "BaseProvider | None":
        return cls._providers.get(name)

    @classmethod
    def all(cls) -> dict[str, "BaseProvider"]:
        return dict(cls._providers)

    @classmethod
    def by_capability(cls, cap: "Capability") -> list["BaseProvider"]:
        return [p for p in cls._providers.values() if cap in p.capabilities]