Add geocoding functionality and enhance Adventure model with location fields

backend/server/adventures/geocoding.py

@@ -0,0 +1,71 @@
+import requests
+from worldtravel.models import Region, City, VisitedRegion, VisitedCity
+
+def extractIsoCode(user, data):
+        """
+        Extract the ISO code from the response data.
+        Returns a dictionary containing the region name, country name, and ISO code if found.
+        """
+        iso_code = None
+        town_city_or_county = None
+        display_name = None
+        country_code = None
+        city = None
+        visited_city = None
+        location_name = None
+
+        # town = None
+        # city = None
+        # county = None
+
+        if 'name' in data.keys():
+            location_name = data['name']
+        
+        if 'address' in data.keys():
+            keys = data['address'].keys()
+            for key in keys:
+                if key.find("ISO") != -1:
+                    iso_code = data['address'][key]
+            if 'town' in keys:
+                town_city_or_county = data['address']['town']
+            if 'county' in keys:
+                town_city_or_county = data['address']['county']
+            if 'city' in keys:
+                town_city_or_county = data['address']['city']
+        if not iso_code:
+            return {"error": "No region found"}
+        
+        region = Region.objects.filter(id=iso_code).first()
+        visited_region = VisitedRegion.objects.filter(region=region, user_id=user).first()
+        
+        region_visited = False
+        city_visited = False
+        country_code = iso_code[:2]
+        
+        if region:
+            if town_city_or_county:
+                display_name = f"{town_city_or_county}, {region.name}, {country_code}"
+                city = City.objects.filter(name__contains=town_city_or_county, region=region).first()
+                visited_city = VisitedCity.objects.filter(city=city, user_id=user).first()
+
+        if visited_region:
+            region_visited = True
+        if visited_city:
+            city_visited = True
+        if region:
+            return {"region_id": iso_code, "region": region.name, "country": region.country.name, "country_id": region.country.country_code, "region_visited": region_visited, "display_name": display_name, "city": city.name if city else None, "city_id": city.id if city else None, "city_visited": city_visited, 'location_name': location_name}
+        return {"error": "No region found"}
+
+def reverse_geocode(lat, lon, user):
+    """
+    Reverse geocode the given latitude and longitude using Nominatim API.
+    Returns a dictionary containing the region name, country name, and ISO code if found.
+    """
+    url = f"https://nominatim.openstreetmap.org/reverse?format=jsonv2&lat={lat}&lon={lon}"
+    headers = {'User-Agent': 'AdventureLog Server'}
+    response = requests.get(url, headers=headers)
+    try:
+        data = response.json()
+    except requests.exceptions.JSONDecodeError:
+        return {"error": "Invalid response from geocoding service"}
+    return extractIsoCode(user, data)