Use pattern matching: train/flight/ferry

agenda/trip.py

@@ -225,33 +225,51 @@ def add_coordinates_for_unbooked_flights(
     )
 
 
-def collect_trip_coordinates(trip: Trip) -> list[StrDict]:
-    """Extract and de-duplicate airport and station coordinates from trip."""
-    stations = {}
+def get_locations(trip: Trip) -> dict[str, StrDict]:
+    """Collect locations of all travel locations in trip."""
+    locations: dict[str, StrDict] = {
+        "station": {},
+        "airport": {},
+        "ferry_terminal": {},
+    }
+
     station_list = []
-    airports = {}
-    ferry_terminals = {}
     for t in trip.travel:
-        if t["type"] == "train":
+        match t["type"]:
+            case "train":
                 station_list += [t["from_station"], t["to_station"]]
                 for leg in t["legs"]:
                     station_list.append(leg["from_station"])
                     station_list.append(leg["to_station"])
-        elif t["type"] == "flight":
+            case "flight":
                 for field in "from_airport", "to_airport":
                     if field in t:
-                    airports[t[field]["iata"]] = t[field]
-        else:
-            assert t["type"] == "ferry"
+                        locations["airport"][t[field]["iata"]] = t[field]
+            case "ferry":
                 for field in "from_terminal", "to_terminal":
                     terminal = t[field]
-                ferry_terminals[terminal["name"]] = terminal
+                    locations["ferry_terminal"][terminal["name"]] = terminal
 
     for s in station_list:
-        if s["uic"] in stations:
+        if s["uic"] in locations["station"]:
             continue
-        stations[s["uic"]] = s
+        locations["station"][s["uic"]] = s
 
+    return locations
+
+
+def coordinate_dict(item: StrDict, coord_type: str) -> StrDict:
+    """Build coodinate dict for item."""
+    return {
+        "name": item["name"],
+        "type": coord_type,
+        "latitude": item["latitude"],
+        "longitude": item["longitude"],
+    }
+
+
+def collect_trip_coordinates(trip: Trip) -> list[StrDict]:
+    """Extract and de-duplicate travel location coordinates from trip."""
     coords = []
 
     src = [
@@ -261,31 +279,14 @@ def collect_trip_coordinates(trip: Trip) -> list[StrDict]:
     ]
     for coord_type, item_list in src:
         coords += [
-            {
-                "name": item["name"],
-                "type": coord_type,
-                "latitude": item["latitude"],
-                "longitude": item["longitude"],
-            }
+            coordinate_dict(item, coord_type)
             for item in item_list
             if "latitude" in item and "longitude" in item
         ]
 
-    locations = [
-        ("station", stations),
-        ("airport", airports),
-        ("ferry_terminal", ferry_terminals),
-    ]
-    for coord_type, coord_dict in locations:
-        coords += [
-            {
-                "name": s["name"],
-                "type": coord_type,
-                "latitude": s["latitude"],
-                "longitude": s["longitude"],
-            }
-            for s in coord_dict.values()
-        ]
+    locations = get_locations(trip)
+    for coord_type, coord_dict in locations.items():
+        coords += [coordinate_dict(s, coord_type) for s in coord_dict.values()]
 
     return coords