From 4143190a8a5fbaab05d779e211bcf917af18bace Mon Sep 17 00:00:00 2001
From: Edward Betts <edward@4angle.com>
Date: Thu, 30 Oct 2025 17:30:27 +0000
Subject: [PATCH] Accommodation must be within 5km of conference

---
 validate_yaml.py | 45 +++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 41 insertions(+), 4 deletions(-)

diff --git a/validate_yaml.py b/validate_yaml.py
index 6cf4028..f49bf49 100755
--- a/validate_yaml.py
+++ b/validate_yaml.py
@@ -4,9 +4,11 @@
 import os
 import sys
 import typing
-from datetime import date, timedelta, datetime
+from datetime import date, datetime, timedelta
+from typing import Tuple, TypeVar
 
 import yaml
+from geopy.distance import distance
 from rich.pretty import pprint
 
 import agenda
@@ -32,6 +34,29 @@ def check_currency(item: agenda.types.StrDict) -> None:
     sys.exit(-1)
 
 
+def get_coords(item):
+    if "latitude" in item and "longitude" in item:
+        return (item["latitude"], item["longitude"])
+    else:
+        return None
+
+
+T = TypeVar("T")
+
+
+def remove_nones(items: list[T | None]) -> list[T]:
+    """Return a new list with None values removed."""
+    return [item for item in items if item is not None]
+
+
+LatLon = Tuple[float, float]
+
+
+def distance_km(a: LatLon, b: LatLon) -> float:
+    """Return the great-circle distance between two (lat, lon) points in km."""
+    return distance(a, b).km
+
+
 def check_trips() -> None:
     """Check trips and ensure they are in chronological order."""
     filepath = os.path.join(data_dir, "trips.yaml")
@@ -42,12 +67,14 @@ def check_trips() -> None:
     for trip_data in trips_data:
         current_trip = normalize_datetime(trip_data["trip"])
         if prev_trip and current_trip < prev_trip:
-            print(f"Out of order trip found:")
+            print("Out of order trip found:")
             print(
-                f"  Previous: {prev_trip_data.get('trip')} - {prev_trip_data.get('name', 'No name')}"
+                f"  Previous: {prev_trip_data.get('trip')} - "
+                + f"{prev_trip_data.get('name', 'No name')}"
             )
             print(
-                f"  Current:  {trip_data.get('trip')} - {trip_data.get('name', 'No name')}"
+                f"  Current:  {trip_data.get('trip')} - "
+                + f"{trip_data.get('name', 'No name')}"
             )
             assert False, "Trips are not in chronological order by trip date."
         prev_trip = current_trip
@@ -56,6 +83,16 @@ def check_trips() -> None:
     trip_list = agenda.trip.build_trip_list(data_dir)
     print(len(trip_list), "trips")
 
+    for trip in trip_list:
+        if not trip.accommodation or not trip.conferences:
+            continue
+        accommodation_coords = remove_nones([get_coords(a) for a in trip.accommodation])
+        conference_coords = remove_nones([get_coords(c) for c in trip.conferences])
+        if len(accommodation_coords) != 1 or len(conference_coords) != 1:
+            continue
+        dist = distance_km(conference_coords[0], accommodation_coords[0])
+        assert dist < 5.0
+
     coords, routes = agenda.trip.get_coordinates_and_routes(trip_list, data_dir)
     print(len(coords), "coords")
     print(len(routes), "routes")