main.py

import requests
from dataclasses import dataclass
from typing import List, Optional, Union
import json

# The API endpoint for USACE NSI structures
url = "https://nsi.sec.usace.army.mil/nsiapi/structures?bbox=-81.58418,30.25165,-81.58161,30.26939,-81.55898,30.26939,-81.55281,30.24998,-81.58418,30.25165"

@dataclass
class Geometry:
    type: str
    coordinates: List[float]

@dataclass
class FeatureProperties:
    fd_id: int
    bid: str
    occtype: str
    st_damcat: str
    bldgtype: str
    found_type: str
    cbfips: int
    pop2amu65: int
    pop2amo65: int
    pop2pmu65: int
    pop2pmo65: int
    sqft: float
    num_story: int
    ftprntid: str
    ftprntsrc: Optional[str]
    students: int
    found_ht: float
    val_struct: float
    val_cont: float
    val_vehic: float
    source: str
    med_yr_blt: int
    firmzone: Optional[str]
    o65disable: float
    u65disable: float
    x: float
    y: float
    ground_elv: float
    ground_elv_m: float

@dataclass
class Feature:
    type: str
    geometry: Geometry
    properties: FeatureProperties

@dataclass
class FeatureCollection:
    type: str
    features: List[Feature]

def parse_geojson(data_dict):
    feature_list = []
    
    for feat in data_dict['features']:
        # Create Geometry object
        geom = Geometry(**feat['geometry'])
        
        # Create Properties object
        prop = FeatureProperties(**feat['properties'])
        
        # Create Feature object
        feature_list.append(Feature(type=feat['type'], geometry=geom, properties=prop))
        
    return FeatureCollection(type=data_dict['type'], features=feature_list)

def download_nsi_data(target_url, output_file):
    try:
        # Send a GET request to the URL
        response = requests.get(target_url)
        
        # Raise an exception for bad status codes (4xx or 5xx)
        response.raise_for_status()
        
        # Parse the response content as JSON
        data = response.json()
        print(f"Successfully downloaded data")
        # Save the JSON data to a file with pretty formatting
        collection = parse_geojson(data)

        # Calculate Stats
        total_val = sum(f.properties.val_struct for f in collection.features)
        total_sqft = sum(f.properties.sqft for f in collection.features)
        avg_sqft = total_sqft / len(collection.features)
        occ_types = [f.properties.occtype for f in collection.features]

        print(f"--- Analysis Summary ---")
        print(f"Features Processed: {len(collection.features)}")
        print(f"Total Structural Value: ${total_val:,.2f}")
        print(f"Average Square Footage: {avg_sqft:,.2f} sqft")
        print(f"Unique Occupancy Types: {set(occ_types)}")
            
        
        
    except requests.exceptions.RequestException as e:
        print(f"An error occurred: {e}")
    except json.JSONDecodeError:
        print("Failed to decode JSON. The response might not be in JSON format.")

if __name__ == "__main__":
    download_nsi_data(url, "nsi_structures.json")