fix incorrect type for direction id, write pseudocode for direction id

algo-for-fetching-departures-for-stop.md

@@ -0,0 +1,33 @@
+- for stop id, fetch all the stops
+
+```rs
+fn get_departures(stop_id: String, chateau: String) -> DepartureBoard {}
+```
+
+```rs
+struct DepartureBoard {
+    updated_time_ms: u64,
+    departures: Vec<DeparturesPerRoute>>
+}
+
+struct DeparturesPerRoute {
+    route_id: String,
+    chateau: String,
+    //headsign -> Sorted Vec of Departures
+    directions: BTreeMap<String, Vec<DepartureArrivalEvent>>
+}
+
+struct DepartureArrivalEvent {
+    stop_id: String,
+    stop_location: geo::Point,
+    stop_code: String,
+    scheduled_departure_time_s: Option<u64>,
+    //optional if the service is the last stop
+    scheduled_arrival_time_s: Option<u64>,
+    actual_departure_time_s: Option<u64>,
+    actual_arrival_time_s: Option<u64>,
+    has_realtime: bool,
+    trip: gtfs_rt::TripDescriptor,
+    is_frequency: bool,
+}
+```

src/models.rs

@@ -44,7 +44,7 @@ pub struct CompressedTrip {
     attempt_id: String,
     service_id: String,
     trip_short_name: Option<String>,
-    direction_id: Option<i16>,
+    direction_id: Option<bool>,
     block_id: String,
     wheelchair_accessible: i16,
     bikes_allowed: i16,