first version of weather loader

apps/weather/src/utils.py

@@ -0,0 +1,40 @@
+import re
+
+
+def format_coord(latitude: float, longitude: float) -> str:
+    """Format latitude and longitude into a string with hemisphere indicators."""
+
+    def to_str(value: float, pos_letter: str, neg_letter: str) -> str:
+        """Convert a coordinate value to a string with hemisphere indicator."""
+        hemi = pos_letter if value >= 0 else neg_letter
+        abs_val = abs(value)
+        degrees = int(abs_val)
+        fraction = int(round((abs_val - degrees) * 100))  # .25 becomes 25
+        return f"{hemi}{degrees:02d}{fraction:02d}"
+
+    lat_str = to_str(latitude, "N", "S")
+    lon_str = to_str(longitude, "E", "W")
+    return f"{lat_str}{lon_str}"
+
+
+def parse_coord(coord: str) -> tuple[float, float]:
+    """
+    Parse a formatted coordinate string (e.g. 'N5225E0040' or 'S1350W12200')
+    back into (latitude, longitude) float values.
+    """
+    # Match hemisphere + degrees + fractional part
+    match = re.match(r"^([NS])(\d{2,3})(\d{2})([EW])(\d{2,3})(\d{2})$", coord)
+    if not match:
+        raise ValueError(f"Invalid coordinate format: {coord}")
+
+    lat_hemi, lat_deg, lat_frac, lon_hemi, lon_deg, lon_frac = match.groups()
+
+    lat = int(lat_deg) + int(lat_frac) / 100.0
+    lon = int(lon_deg) + int(lon_frac) / 100.0
+
+    if lat_hemi == "S":
+        lat = -lat
+    if lon_hemi == "W":
+        lon = -lon
+
+    return lat, lon