def geocode_location(query):
    url = "https://nominatim.openstreetmap.org/search"
    params = {
        "q": query,
        "format": "json",
        "limit": 1,
    }
    headers = {
        "User-Agent": "ChallengeApp/1.0 ([email protected])"
    }

    try:
        response = requests.get(url, params=params, headers=headers)
        response.raise_for_status()
        data = response.json()
        if data:
            return float(data[0]["lat"]), float(data[0]["lon"])
    except:
        return None, None

class ChallengeSerializer(serializers.ModelSerializer):
    is_active = serializers.SerializerMethodField()

    class Meta:
        model = Challenge
        fields = '__all__'
        read_only_fields = ['coach', 'created_at', 'is_active']

    def get_is_active(self, obj):
        return obj.is_active()

    def create(self, validated_data):
        ...
        location = validated_data.get('location')
        if (not validated_data.get('latitude') or not validated_data.get('longitude')) and location:
            lat, lon = geocode_location(location)
            validated_data['latitude'] = lat
            validated_data['longitude'] = lon
        return super().create(validated_data)

    def update(self, instance, validated_data):
        ...
        location = validated_data.get('location', instance.location)
        lat = validated_data.get('latitude', instance.latitude)
        lon = validated_data.get('longitude', instance.longitude)
        if (lat is None or lon is None) and location:
            lat, lon = geocode_location(location)
            validated_data['latitude'] = lat
            validated_data['longitude'] = lon
        return super().update(instance, validated_data)