Add type checking for img detection messages

ml/messages/__init__.py

@@ -1 +1,6 @@
-from .img_detections import ImgDetectionsWithKeypoints
+from .img_detections import ImgDetectionWithKeypoints, ImgDetectionsWithKeypoints
+
+__all__ = [
+    "ImgDetectionWithKeypoints",
+    "ImgDetectionsWithKeypoints",
+]

ml/messages/img_detections.py

@@ -1,12 +1,49 @@
 import depthai as dai
-from typing import List
+from typing import List, Tuple, Union
+
 
 class ImgDetectionWithKeypoints(dai.ImgDetection):
     def __init__(self):
-        dai.ImgDetection.__init__(self)
-        self.keypoints = [] # TODO: how to enforce type checking for keypoints? e.g. this currently accept strings
+        dai.ImgDetection.__init__(self)  # TODO: change to super().__init__()?
+        self._keypoints: List[Tuple[float, float]] = []
+
+    @property
+    def keypoints(self) -> List[Tuple[float, float]]:
+        return self._keypoints
+
+    @keypoints.setter
+    def keypoints(self, value: List[Tuple[Union[int, float], Union[int, float]]]):
+        if not isinstance(value, list):
+            raise TypeError("Keypoints must be a list")
+        for item in value:
+            if (
+                not isinstance(item, tuple)
+                or len(item) != 2
+                or not all(isinstance(i, (int, float)) for i in item)
+            ):
+                raise TypeError(
+                    "Each keypoint must be a tuple of two floats or integers"
+                )
+        self._keypoints = [(float(x), float(y)) for x, y in value]
+
 
 class ImgDetectionsWithKeypoints(dai.Buffer):
+
     def __init__(self):
-        dai.Buffer.__init__(self)
-        self.detections: List[ImgDetectionWithKeypoints] = [] # TODO: how to enforce type checking for ImgDetectionWithKeypoints? e.g. this currently accept ImgDetection
+        dai.Buffer.__init__(self)  # TODO: change to super().__init__()?
+        self._detections: List[ImgDetectionWithKeypoints] = []
+
+    @property
+    def detections(self) -> List[ImgDetectionWithKeypoints]:
+        return self._detections
+
+    @detections.setter
+    def detections(self, value: List[ImgDetectionWithKeypoints]):
+        if not isinstance(value, list):
+            raise TypeError("Detections must be a list")
+        for item in value:
+            if not isinstance(item, ImgDetectionWithKeypoints):
+                raise TypeError(
+                    "Each detection must be an instance of ImgDetectionWithKeypoints"
+                )
+        self._detections = value