1 files changed, 164 insertions, 0 deletions
diff --git a/src/hrc/rule/__init__.py b/src/hrc/rule/__init__.py
new file mode 100644
index 0000000..282e3e2
--- /dev/null
+++ b/src/hrc/rule/__init__.py
@@ -0,0 +1,164 @@
+import functools  # noqa: F401
+from typing import Generic, Any, Type
+
+from abc import ABC
+
+from hrc.rule import BaseRule  # noqa: F401
+from hrc.typing import RuleT  # noqa: F401
+
+import inspect
+from abc import abstractmethod  # noqa: F401
+from enum import Enum
+from typing import (
+    TYPE_CHECKING,
+    ClassVar,
+    NoReturn,
+    Optional,
+    Tuple,
+    cast,
+    final,
+)
+from typing_extensions import Annotated, get_args, get_origin
+
+from hrc.config import ConfigModel
+
+from hrc.dependencies import Depends
+from hrc.event import Event
+from hrc.exceptions import SkipException, StopException
+from hrc.typing import ConfigT, EventT, StateT
+from hrc.utils import is_config_class
+
+if TYPE_CHECKING:
+    from hrc.core import Core
+
+
+class RuleLoadType(Enum):
+    """Rules loaded types."""
+
+    DIR = "dir"
+    NAME = "name"
+    FILE = "file"
+    CLASS = "class"
+
+
+class Rule(ABC, Generic[EventT, StateT, ConfigT]):
+    priority: ClassVar[int] = 0
+    block: ClassVar[bool] = False
+
+    # Cannot use ClassVar because PEP 526 does not allow it
+    Config: Type[ConfigT]
+
+    __rule_load_type__: ClassVar[RuleLoadType]
+    __rule_file_path__: ClassVar[Optional[str]]
+
+    if TYPE_CHECKING:
+        event: EventT
+    else:
+        event = Depends(Event)  # noqa: F821
+
+    def __init_state__(self) -> Optional[StateT]:
+        """Initialize rule state."""
+
+    def __init_subclass__(
+        cls,
+        config: Optional[Type[ConfigT]] = None,
+        init_state: Optional[StateT] = None,
+        **_kwargs: Any,
+    ) -> None:
+        super().__init_subclass__()
+
+        orig_bases: Tuple[type, ...] = getattr(cls, "__orig_bases__", ())
+        for orig_base in orig_bases:
+            origin_class = get_origin(orig_base)
+            if inspect.isclass(origin_class) and issubclass(origin_class, Rule):
+                try:
+                    _event_t, state_t, config_t = cast(
+                        Tuple[EventT, StateT, ConfigT], get_args(orig_base)
+                    )
+                except ValueError:  # pragma: no cover
+                    continue
+                if (
+                    config is None
+                    and inspect.isclass(config_t)
+                    and issubclass(config_t, ConfigModel)
+                ):
+                    config = config_t  # pyright: ignore
+                if (
+                    init_state is None
+                    and get_origin(state_t) is Annotated
+                    and hasattr(state_t, "__metadata__")
+                ):
+                    init_state = state_t.__metadata__[0]  # pyright: ignore
+
+        if not hasattr(cls, "Config") and config is not None:
+            cls.Config = config
+        if cls.__init_state__ is Rule.__init_state__ and init_state is not None:
+            cls.__init_state__ = lambda _: init_state  # type: ignore
+
+    @final
+    @property
+    def name(self) -> str:
+        """rule class name."""
+        return self.__class__.__name__
+
+    @final
+    @property
+    def core(self) -> "Core":
+        """core object."""
+        return self.event.core  # pylint: disable=no-member
+
+    @final
+    @property
+    def config(self) -> ConfigT:
+        """rule configuration."""
+        default: Any = None
+        config_class = getattr(self, "Config", None)
+        if is_config_class(config_class):
+            return getattr(
+                self.core.config.rule,
+                config_class.__config_name__,
+                default,
+            )
+        return default
+
+    @final
+    def stop(self) -> NoReturn:
+        """Stop propagation of current events."""
+        raise StopException
+
+    @final
+    def skip(self) -> NoReturn:
+        """Skips itself and continues propagation of the current event."""
+        raise SkipException
+
+    @property
+    def state(self) -> StateT:
+        """rule status."""
+        return self.core.rule_state[self.name]
+
+    @state.setter
+    @final
+    def state(self, value: StateT) -> None:
+        self.core.rule_state[self.name] = value
+
+    async def enable(self): ...
+
+    async def disable(self): ...
+
+    @staticmethod
+    def aliases(names, ignore_case=False):
+        def decorator(func):
+            func._aliases = names
+            func._ignore_case = ignore_case
+            return func
+
+        return decorator
+
+    @final
+    async def safe_run(self) -> None:
+        try:
+            await self.enable()
+        except Exception as e:
+            self.bot.error_or_exception(
+                f"Enable rule  {self.__class__.__name__} failed:", e
+            )