Behavioural Design Pattern: State Pattern

app/io.py

@@ -2,36 +2,103 @@
 import json
 import pathlib
 from typing import Dict, List, Union
+from abc import ABC, abstractmethod
 
 import aiofiles
 
-HERE = pathlib.Path(__file__)
-DATA = HERE.joinpath("..", "data").resolve()
-
-
-def save(
-    name: str,
-    content: Union[str, Dict, List],
-    write_mode: str = "w",
-    indent: int = 2,
-    **json_dumps_kwargs,
-) -> pathlib.Path:
-    """Save content to a file. If content is a dictionary, use json.dumps()."""
-    path = DATA / name
-    if isinstance(content, (dict, list)):
-        content = json.dumps(content, indent=indent, **json_dumps_kwargs)
-    with open(DATA / name, mode=write_mode) as f_out:
-        f_out.write(content)
-    return path
-
-
-def load(name: str, **json_kwargs) -> Union[str, Dict, List]:
-    """Loads content from a file. If file ends with '.json', call json.load() and return a Dictionary."""
-    path = DATA / name
-    with open(path) as f_in:
-        if path.suffix == ".json":
-            return json.load(f_in, **json_kwargs)
-        return f_in.read()
+from __future__ import annotations
+
+
+
+class Context:
+
+    _state = None
+
+
+    def __init__(self, state):
+        self.transition_to(state)
+
+    def transition_to(self, state: State):
+
+        self._state = state
+        self._state.context = self
+
+
+
+    def request_save(self):
+        self._state.handle_save()
+
+    def request_load(self):
+        self._state.handle_load()
+
+
+class State(ABC):
+    HERE = pathlib.Path(__file__)
+    DATA = HERE.joinpath("..", "data").resolve()
+    @property
+    def context(self):
+        return self._context
+
+    @context.setter
+    def context(self, context: Context):
+        self._context = context
+
+    @abstractmethod
+    def handle_save(self) -> None:
+        pass
+
+    @abstractmethod
+    def handle_load(self) -> None:
+        pass
+
+
+class SaveState(State):
+    def handle_save(self, name: str,
+                    content: Union[str, Dict, List],
+                    write_mode: str = "w",
+                    indent: int = 2,
+                    **json_dumps_kwargs,):
+        """Save content to a file. If content is a dictionary, use json.dumps()."""
+        path = self.DATA / name
+        if isinstance(content, (dict, list)):
+            content = json.dumps(content, indent=indent, **json_dumps_kwargs)
+        with open(self.DATA / name, mode=write_mode) as f_out:
+            f_out.write(content)
+        return path
+
+class LoadState(State):
+    def handle_load(name: str, **json_kwargs):
+        path = DATA / name
+        with open(path) as f_in:
+            if path.suffix == ".json":
+                return json.load(f_in, **json_kwargs)
+            return f_in.read()
+
+
+
+# def save(
+#     name: str,
+#     content: Union[str, Dict, List],
+#     write_mode: str = "w",
+#     indent: int = 2,
+#     **json_dumps_kwargs,
+# ) -> pathlib.Path:
+#     """Save content to a file. If content is a dictionary, use json.dumps()."""
+#     path = DATA / name
+#     if isinstance(content, (dict, list)):
+#         content = json.dumps(content, indent=indent, **json_dumps_kwargs)
+#     with open(DATA / name, mode=write_mode) as f_out:
+#         f_out.write(content)
+#     return path
+
+
+# def load(name: str, **json_kwargs) -> Union[str, Dict, List]:
+#     """Loads content from a file. If file ends with '.json', call json.load() and return a Dictionary."""
+#     path = DATA / name
+#     with open(path) as f_in:
+#         if path.suffix == ".json":
+#             return json.load(f_in, **json_kwargs)
+#         return f_in.read()
 
 
 class AIO: