From 051b92a716807cafc96f9b2df07ed160fe5318a7 Mon Sep 17 00:00:00 2001
From: Alex Root Junior <jroot.junior@gmail.com>
Date: Thu, 28 Jun 2018 18:51:00 +0300
Subject: [PATCH] More usable state groups. All child groups know about name of
 parent group.

---
 aiogram/dispatcher/filters/builtin.py |  7 ++-
 aiogram/dispatcher/filters/state.py   | 82 +++++++++++++++++++++++----
 2 files changed, 75 insertions(+), 14 deletions(-)

diff --git a/aiogram/dispatcher/filters/builtin.py b/aiogram/dispatcher/filters/builtin.py
index 7fd3866f..d9588481 100644
--- a/aiogram/dispatcher/filters/builtin.py
+++ b/aiogram/dispatcher/filters/builtin.py
@@ -1,3 +1,4 @@
+import inspect
 import re
 from _contextvars import ContextVar
 
@@ -116,7 +117,7 @@ class StateFilter(BaseFilter):
     ctx_state = ContextVar('user_state')
 
     def __init__(self, dispatcher, state):
-        from aiogram.dispatcher.filters.state import State
+        from aiogram.dispatcher.filters.state import State, StatesGroup
 
         super().__init__(dispatcher)
         states = []
@@ -125,8 +126,8 @@ class StateFilter(BaseFilter):
         for item in state:
             if isinstance(item, State):
                 states.append(item.state)
-            elif hasattr(item, 'state_names'):  # issubclass() cannot be used in this place
-                states.extend(item.state_names)
+            elif inspect.isclass(item) and issubclass(item, StatesGroup):
+                states.extend(item.all_state_names)
             else:
                 states.append(item)
         self.states = states
diff --git a/aiogram/dispatcher/filters/state.py b/aiogram/dispatcher/filters/state.py
index 36b567b4..a8b76736 100644
--- a/aiogram/dispatcher/filters/state.py
+++ b/aiogram/dispatcher/filters/state.py
@@ -1,16 +1,38 @@
+import inspect
+from typing import Optional
+
 from ..dispatcher import Dispatcher
 
 
 class State:
-    def __init__(self, state=None):
-        self.state = state
+    """
+    State object
+    """
+
+    def __init__(self, state: Optional[str] = None, group_name: Optional[str] = None):
+        self._state = state
+        self._group_name = group_name
+        self._group = None
+
+    @property
+    def state(self):
+        if self._group_name is None and self._group:
+            group = self._group.__full_group_name__
+        elif self._group_name:
+            group = self._group_name
+        else:
+            group = '*'
+        return f"{group}:{self._state}"
+
+    def set_parent(self, group):
+        if not issubclass(group, StatesGroup):
+            raise ValueError('Group must be subclass of StatesGroup')
+        self._group = group
 
     def __set_name__(self, owner, name):
-        if self.state is None:
-            group_name = getattr(owner, '__group_name__')
-            if group_name is None:
-                group_name = owner.__name__
-            self.state = f"{group_name}:{name}"
+        if self._state is None:
+            self._state = name
+        self.set_parent(owner)
 
     def __str__(self):
         return f"<State '{self.state}>'"
@@ -27,26 +49,64 @@ class MetaStatesGroup(type):
         cls = super(MetaStatesGroup, mcs).__new__(mcs, name, bases, namespace)
 
         states = []
-        for name, prop in ((name, prop) for name, prop in namespace.items() if isinstance(prop, State)):
-            states.append(prop)
+        childs = []
 
+        cls._group_name = name
+
+        for name, prop in namespace.items():
+
+            if isinstance(prop, State):
+                states.append(prop)
+            elif inspect.isclass(prop) and issubclass(prop, StatesGroup):
+                childs.append(prop)
+                prop._parent = cls
+            # continue
+
+        cls._parent = None
+        cls._childs = tuple(childs)
         cls._states = tuple(states)
         cls._state_names = tuple(state.state for state in states)
 
         return cls
 
+    @property
+    def __group_name__(cls):
+        return cls._group_name
+
+    @property
+    def __full_group_name__(cls):
+        if cls._parent:
+            return cls._parent.__full_group_name__ + '.' + cls._group_name
+        return cls._group_name
+
     @property
     def states(cls) -> tuple:
         return cls._states
 
+    @property
+    def childs(cls):
+        return cls._childs
+
+    @property
+    def all_states(cls):
+        result = cls.states
+        for group in cls.childs:
+            result += group.all_states
+        return result
+
+    @property
+    def all_state_names(cls):
+        return tuple(state.state for state in cls.all_states)
+
+    def __str__(self):
+        return f"<StatesGroup '{self.__full_group_name__}'>"
+
     @property
     def state_names(cls) -> tuple:
         return cls._state_names
 
 
 class StatesGroup(metaclass=MetaStatesGroup):
-    __group_name__ = None
-
     @classmethod
     async def next(cls) -> str:
         state = Dispatcher.current().current_state()