feat: add keyboard navigation with Cursor and Input classes

src/IO/Input.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from .App import App
+
+
+class Input:
+    def __init__(self, app: App) -> None:
+        self._app = app
+
+    def handle(self, key: str) -> bool:
+        if 'q' == key:
+            return False
+        elif key in ('j', 'KEY_DOWN'):
+            self.app.cursor.down(len(self.app.items))
+        elif key in ('k', 'KEY_UP'):
+            self.app.cursor.up()
+        return True
+
+    @property
+    def app(self) -> App:
+        return self._app
+
+        

src/IO/UI.py

@@ -15,7 +15,7 @@ class UI:
 
     def _get_attr(self, item: any, i: int) -> str:
         attr = curses.color_pair(item.color_pair)
-        if i == self.app.cursor:
+        if i == self.app.cursor.pos:
             attr |= curses.A_REVERSE
         return attr
 
@@ -38,7 +38,7 @@ class UI:
         if type(item) is Symlink:
             attr_arrow = curses.color_pair(0)
             attr_target = curses.color_pair(Symlink.target_color(item.point_to))
-            if i == self.app.cursor:
+            if i == self.app.cursor.pos:
                 attr_arrow |= curses.A_REVERSE
                 attr_target |= curses.A_REVERSE
             stdscr.addstr(i, name_len, self.ARROW, attr_arrow)

src/core/App.py

@@ -1,6 +1,8 @@
-from .items.Folder import Folder
+from ..items.Folder import Folder
 from pathlib import Path
-from .IO.UI import UI
+from ..IO.UI import UI
+from ..IO.Input import Input
+from .Cursor import Cursor
 import curses
 
 
@@ -16,7 +18,8 @@ class App():
         self._current = Folder(path)
         self._items = self.current.children()
         self._UI = UI(self)
-        self._cursor = 2
+        self._input = Input(self)
+        self._cursor = Cursor()
 
     def _run(self, stdscr: curses.window) -> None:
         curses.curs_set(0)
@@ -37,7 +40,7 @@ class App():
             stdscr.refresh()
             key = stdscr.getkey()
             self._items = self.current.children()
-            if 'q' == key:
+            if False == self.input.handle(key):
                 break
 
     def run(self) -> None:
@@ -60,5 +63,9 @@ class App():
         return self._UI
 
     @property
-    def cursor(self) -> int:
+    def input(self) -> Input:
+        return self._input
+
+    @property
+    def cursor(self) -> Cursor:
         return self._cursor

src/core/Cursor.py

@@ -0,0 +1,14 @@
+
+class Cursor:
+    def __init__(self) -> None:
+        self._pos = 0
+
+    def up(self) -> None:
+        self._pos -= 1 if self.pos >= 1 else 0
+
+    def down(self, max: int) -> None:
+        self._pos = min(self.pos + 1, max - 1)
+
+    @property
+    def pos(self) -> int:
+        return self._pos

src/main.py

@@ -1,4 +1,4 @@
-from .App import App
+from .core.App import App
 from pathlib import Path
 import sys