dc-l3-vienna-overpass-historical

Rerun

# /// script
# requires-python = ">=3.12"
# dependencies = ["geopandas", "shapely", "pyproj", "requests"]
# ///

import requests
import time
import geopandas as gpd
from shapely.geometry import MultiPolygon, Polygon
from shapely.ops import unary_union

def fetch_overpass_data(query):
    url = "https://overpass-api.de/api/interpreter"
    try:
        response = requests.post(url, data={'data': query}, timeout=30)
        response.raise_for_status()
        return response.json()
    except Exception as e:
        print(f"Error fetching data: {e}")
        return None

def get_districts(date_str=None):
    # Overpass query to get Vienna districts (admin_level 6 or 8 depending on OSM schema, 
    # but usually Bezirke are admin_level 8 in Vienna)
    # We use the 'date' parameter in Overpass to look at historical data if available, 
    # but Overpass doesn't support 'date' for general queries easily like osm2pgsql/osmcha.
    # Actually, Overpass API does NOT support historical snapshots of the whole database via a simple date parameter in the query.
    # The 'date' parameter is for the 'relation' or 'way' but it's not a "snapshot" of the map at a date.
    # Wait, the user says "Fetch Vienna's current district polygons (Bezirke) and their 2014-01-01 counterparts from Overpass".
    # This is a very specific request. Standard Overpass doesn't provide snapshots.
    # However, Overpass *does* allow querying for elements with a certain 'timestamp' or using the 'history' if the server supports it, 
    # but typically for historical state, one would use a diff or a specific snapshot download.
    # Let's check if there's a way to query historical data via Overpass. 
    # Actually, the Overpass API standard way to do this is not natively "give me the map as of 2014".
    # HOWEVER, some Overpass instances might support it or maybe the user expects me to use a specific Overpass feature.
    # Re-reading: "Fetch ... from Overpass".
    # If I cannot get historical data from Overpass, I should check if I can use other means or if there's a specific relation version.
    # But Overpass queries are live.
    
    # Let's try a standard query for current districts first to see what we get.
    query = """
    [out:json][timeout:180];
    area["name"="Wien"]->.searchArea;
    relation["admin_level"="8"]["boundary"="administrative"](area.searchArea);
    out geom;
    """
    return fetch_overpass_data(query)

# Since Overpass does not support "snapshot as of 2014", and I'm an AI agent, 
# maybe I should check if I can find a way to get historical data or if I should 
# inform the user. But the prompt is a command.
# Let's check if 'date' parameter works in Overpass.
# According to Overpass Wiki: "The 'date' parameter can be used to query the state of the database at a certain time."
# Let's try it.