better structure

backend/src/utils/bbox.py

@@ -0,0 +1,27 @@
+"""Various helper functions"""
+import math as m
+
+def create_bbox(coords: tuple[float, float], radius: int):
+    """
+    Create a bounding box around the given coordinates.
+
+    Args:
+        coords (tuple[float, float]): The latitude and longitude of the center of the bounding box.
+        radius (int): The half-side length of the bounding box in meters.
+
+    Returns:
+        tuple[float, float, float, float]: The minimum latitude, minimum longitude, maximum latitude, and maximum longitude
+                                            defining the bounding box.
+    """
+    # Earth's radius in meters
+    R = 6378137
+    lat, lon = coords
+    d_lat = radius / R
+    d_lon = radius / (R * m.cos(m.pi * lat / 180))
+
+    lat_min = lat - d_lat * 180 / m.pi
+    lat_max = lat + d_lat * 180 / m.pi
+    lon_min = lon - d_lon * 180 / m.pi
+    lon_max = lon + d_lon * 180 / m.pi
+
+    return (lat_min, lon_min, lat_max, lon_max)