feature: add get zoom/focus, discrete set zoom/focus commands, and get/set autofocus (#89)

* zoom and focus commands

* get and set autofocus

* fix SetAutoFocus api call

* update readme

Author: stevebriskin

README.md

@@ -109,8 +109,8 @@ GET:
 - [X] User -> Manage User
 - [X] Device -> HDD/SD Card
 - [x] PTZ -> Presets, Calibration Status
-- [ ] Zoom
-- [ ] Focus
+- [x] Zoom
+- [x] Focus
 - [ ] Image (Brightness, Contrast, Saturation, Hue, Sharp, Mirror, Rotate)
 - [ ] Advanced Image (Anti-flicker, Exposure, White Balance, DayNight, Backlight, LED light, 3D-NR)
 - [X] Image Data -> "Snap" Frame from Video Stream
@@ -152,6 +152,7 @@ do not work and is not supported here.
 - RLC-410-5MP
 - RLC-510A
 - RLC-520
+- RLC-823A
 - C1-Pro
 - D400
 - E1 Zoom

reolinkapi/mixins/zoom.py

@@ -16,6 +16,31 @@ def _stop_zooming_or_focusing(self) -> Dict:
         data = [{"cmd": "PtzCtrl", "action": 0, "param": {"channel": 0, "op": "Stop"}}]
         return self._execute_command('PtzCtrl', data)
 
+    def get_zoom_focus(self) -> Dict:
+        """This command returns the current zoom and focus values."""
+        data = [{"cmd": "GetZoomFocus", "action": 0, "param": {"channel": 0}}]
+        return self._execute_command('GetZoomFocus', data)
+
+    def start_zoom_pos(self, position: float) -> Dict:
+        """This command sets the zoom position."""
+        data = [{"cmd": "StartZoomFocus", "action": 0, "param": {"ZoomFocus": {"channel": 0, "op": "ZoomPos", "pos": position}}}]
+        return self._execute_command('StartZoomFocus', data)
+
+    def start_focus_pos(self, position: float) -> Dict:
+        """This command sets the focus position."""
+        data = [{"cmd": "StartZoomFocus", "action": 0, "param": {"ZoomFocus": {"channel": 0, "op": "FocusPos", "pos": position}}}]
+        return self._execute_command('StartZoomFocus', data)
+
+    def get_auto_focus(self) -> Dict:
+        """This command returns the current auto focus status."""
+        data = [{"cmd": "GetAutoFocus", "action": 0, "param": {"channel": 0}}]
+        return self._execute_command('GetAutoFocus', data)
+    
+    def set_auto_focus(self, disable: bool) -> Dict:
+        """This command sets the auto focus status."""
+        data = [{"cmd": "SetAutoFocus", "action": 0, "param": {"AutoFocus": {"channel": 0, "disable": 1 if disable else 0}}}]
+        return self._execute_command('SetAutoFocus', data)
+
     def start_zooming_in(self, speed: float = 60) -> Dict:
         """
         The camera zooms in until self.stop_zooming() is called.