1 files changed, 54 insertions, 4 deletions
diff --git a/tools/cru-py/cru/service/_base.py b/tools/cru-py/cru/service/_base.py
index 707fb66..7bb09ad 100644
--- a/tools/cru-py/cru/service/_base.py
+++ b/tools/cru-py/cru/service/_base.py
@@ -1,23 +1,73 @@
+from __future__ import annotations
+
 from argparse import ArgumentParser, Namespace
-from typing import Protocol
+from abc import ABC, abstractmethod
+from collections.abc import Iterable
+
+from cru import CruIterator, CruInternalError
 from cru.app import ApplicationPath, CruApplication
 
 
-class AppFunction(Protocol):
+class AppFeatureProvider(ABC):
+    def __init__(self, name: str, /, app: AppBase | None = None):
+        super().__init__()
+        self._name = name
+        self._app = app if app else AppBase.get_instance()
+        self._app_paths: list[ApplicationPath] = []
+        self.app.add_app_feature(self)
+
+    @property
+    def app(self) -> AppBase:
+        return self._app
+
+    @property
+    def name(self) -> str:
+        return self._name
+
     @property
-    def name(self) -> str: ...
+    def app_paths(self) -> list[ApplicationPath]:
+        return self._app_paths
+
+    def add_app_path(self, subpath: str, is_dir: bool) -> ApplicationPath:
+        p = ApplicationPath(self.app.app_dir, subpath, is_dir)
+        self._app_paths.append(p)
+        return p
 
+    @abstractmethod
     def add_arg_parser(self, arg_parser: ArgumentParser) -> None: ...
 
+    @abstractmethod
     def run_command(self, args: Namespace) -> None: ...
 
 
 class AppBase(CruApplication):
+    _instance: AppBase | None = None
+
+    @staticmethod
+    def get_instance() -> AppBase:
+        if AppBase._instance is None:
+            raise CruInternalError("App instance not initialized")
+        return AppBase._instance
+
     def __init__(self, name: str, app_dir: str):
         super().__init__(name)
+        AppBase._instance = self
         self._app_dir = app_dir
-        self._template_dir = ApplicationPath(app_dir, "templates", True)
+        self._app_features: list[AppFeatureProvider] = []
 
     @property
     def app_dir(self) -> str:
         return self._app_dir
+
+    @property
+    def app_features(self) -> list[AppFeatureProvider]:
+        return self._app_features
+
+    @property
+    def app_paths(self) -> Iterable[ApplicationPath]:
+        return (
+            CruIterator(self._app_features).transform(lambda x: x.app_paths).flatten(1)
+        )
+
+    def add_app_feature(self, feature: AppFeatureProvider) -> None:
+        self._app_features.append(feature)