Crowding data confidence determination (#673)

* Add locations feed engine

* Add unit test for 'deletion' logic

* Add a few more tests

* remmove io puts

* fix typedef

* Begin reading in multi_carriage_details field

* Calculate crowding data confidence level

* Branch arrival and approaching audio logic based on crowding data confidence level

* Add a todo for where to incorporate read loop selection logic

* Clean up calculation logic

* adjust mapping logic to match actual schema

* Address PR comments

* Use fully qualified name for CarriageDetails type

lib/content/audio/predictions.ex

@@ -46,26 +46,51 @@ defmodule Content.Audio.Predictions do
         ]
 
       predictions.minutes == :arriving ->
-        [
-          %TrainIsArriving{
-            destination: predictions.destination,
-            trip_id: predictions.trip_id,
-            platform: predictions.platform,
-            route_id: predictions.route_id
-          }
-        ]
+        if predictions.crowding_data_confidence == :high do
+          # TODO: Pass along crowding data classification once available
+          [
+            %TrainIsArriving{
+              destination: predictions.destination,
+              trip_id: predictions.trip_id,
+              platform: predictions.platform,
+              route_id: predictions.route_id
+            }
+          ]
+        else
+          [
+            %TrainIsArriving{
+              destination: predictions.destination,
+              trip_id: predictions.trip_id,
+              platform: predictions.platform,
+              route_id: predictions.route_id
+            }
+          ]
+        end
 
       predictions.minutes == :approaching and (line == :top or multi_source?) and
           predictions.route_id in @heavy_rail_routes ->
-        [
-          %Approaching{
-            destination: predictions.destination,
-            trip_id: predictions.trip_id,
-            platform: predictions.platform,
-            route_id: predictions.route_id,
-            new_cars?: predictions.new_cars?
-          }
-        ]
+        if predictions.crowding_data_confidence == :high do
+          # TODO: Pass along crowding data classification once available
+          [
+            %Approaching{
+              destination: predictions.destination,
+              trip_id: predictions.trip_id,
+              platform: predictions.platform,
+              route_id: predictions.route_id,
+              new_cars?: predictions.new_cars?
+            }
+          ]
+        else
+          [
+            %Approaching{
+              destination: predictions.destination,
+              trip_id: predictions.trip_id,
+              platform: predictions.platform,
+              route_id: predictions.route_id,
+              new_cars?: predictions.new_cars?
+            }
+          ]
+        end
 
       predictions.minutes == :approaching ->
         [

lib/content/message/predictions.ex

@@ -31,7 +31,8 @@ defmodule Content.Message.Predictions do
     platform: nil,
     new_cars?: false,
     terminal?: false,
-    certainty: nil
+    certainty: nil,
+    crowding_data_confidence: nil
   ]
 
   @type t :: %__MODULE__{
@@ -47,7 +48,8 @@ defmodule Content.Message.Predictions do
           zone: String.t() | nil,
           platform: Content.platform() | nil,
           terminal?: boolean(),
-          certainty: non_neg_integer() | nil
+          certainty: non_neg_integer() | nil,
+          crowding_data_confidence: :high | :low | nil
         }
 
   @spec non_terminal(
@@ -77,6 +79,14 @@ defmodule Content.Message.Predictions do
         true -> predicted_time |> Kernel./(60) |> round()
       end
 
+    crowding_data_confidence =
+      calculate_crowding_data_confidence(
+        prediction,
+        Engine.Locations.for_vehicle(prediction.vehicle_id)
+      )
+
+    # TODO: Calculate crowding data classification and pass that along as well
+
     case Content.Utilities.destination_for_prediction(
            prediction.route_id,
            prediction.direction_id,
@@ -95,7 +105,8 @@ defmodule Content.Message.Predictions do
           station_code: station_code,
           zone: zone,
           platform: platform,
-          certainty: certainty
+          certainty: certainty,
+          crowding_data_confidence: crowding_data_confidence
         }
 
       {:error, _} ->
@@ -143,6 +154,17 @@ defmodule Content.Message.Predictions do
     end
   end
 
+  defp calculate_crowding_data_confidence(_prediction, nil), do: nil
+
+  defp calculate_crowding_data_confidence(prediction, location)
+       when prediction.route_id in ["Orange"] and location.stop_id == prediction.stop_id do
+    if location.status in [:incoming_at, :in_transit_to],
+      do: :high,
+      else: :low
+  end
+
+  defp calculate_crowding_data_confidence(_prediction, _location), do: nil
+
   defimpl Content.Message do
     require Logger
 

lib/engine/locations.ex

@@ -135,16 +135,42 @@ defmodule Engine.Locations do
   defp location_from_update(location) do
     %Locations.Location{
       vehicle_id: get_in(location, ["vehicle", "vehicle", "id"]),
-      status: status_to_atom(location["vehicle"]["current_status"]),
+      status: vehicle_status_to_atom(location["vehicle"]["current_status"]),
       stop_id: location["vehicle"]["stop_id"],
       timestamp: location["vehicle"]["timestamp"],
       route_id: location["vehicle"]["trip"]["route_id"],
       trip_id: location["vehicle"]["trip"]["trip_id"],
-      consist: location["vehicle"]["vehicle"]["consist"]
+      consist: location["vehicle"]["vehicle"]["consist"],
+      multi_carriage_details:
+        location["vehicle"]["multi_carriage_details"] &&
+          Enum.map(
+            location["vehicle"]["multi_carriage_details"],
+            &parse_carriage_details/1
+          )
     }
   end
 
-  defp status_to_atom(status) do
+  defp parse_carriage_details(multi_carriage_details) do
+    %Locations.CarriageDetails{
+      label: multi_carriage_details["label"],
+      occupancy_status: occupancy_status_to_atom(multi_carriage_details["occupancy_status"]),
+      occupancy_percentage: multi_carriage_details["occupancy_percentage"],
+      carriage_sequence: multi_carriage_details["carriage_sequence"]
+    }
+  end
+
+  defp occupancy_status_to_atom(status) do
+    case status do
+      "MANY_SEATS_AVAILABLE" -> :many_seats_available
+      "FEW_SEATS_AVAILABLE" -> :few_seats_available
+      "STANDING_ROOM_ONLY" -> :standing_room_only
+      "CRUSHED_STANDING_ROOM_ONLY" -> :crushed_standing_room_only
+      "FULL" -> :full
+      _ -> :unknown
+    end
+  end
+
+  defp vehicle_status_to_atom(status) do
     case status do
       "INCOMING_AT" -> :incoming_at
       "STOPPED_AT" -> :stopped_at

lib/locations/carriage_details.ex

@@ -0,0 +1,18 @@
+defmodule Locations.CarriageDetails do
+  defstruct label: nil,
+            occupancy_status: nil,
+            occupancy_percentage: nil,
+            carriage_sequence: nil
+
+  @type t :: %__MODULE__{
+          label: String.t(),
+          occupancy_status:
+            :many_seats_available
+            | :few_seats_available
+            | :standing_room_only
+            | :crushed_standing_room_only
+            | :full,
+          occupancy_percentage: non_neg_integer(),
+          carriage_sequence: non_neg_integer()
+        }
+end

lib/locations/location.ex

@@ -5,7 +5,8 @@ defmodule Locations.Location do
             timestamp: nil,
             route_id: nil,
             trip_id: nil,
-            consist: []
+            consist: [],
+            multi_carriage_details: []
 
   @type t :: %__MODULE__{
           vehicle_id: String.t() | nil,
@@ -14,6 +15,7 @@ defmodule Locations.Location do
           timestamp: DateTime.t() | nil,
           route_id: String.t() | nil,
           trip_id: String.t() | nil,
-          consist: list()
+          consist: list(),
+          multi_carriage_details: list(Locations.CarriageDetails.t())
         }
 end

lib/signs/utilities/audio.ex

@@ -146,6 +146,7 @@ defmodule Signs.Utilities.Audio do
         {[], sign.announced_approachings, sign.announced_arrivals},
         fn audio, {new_audios, new_approaching_trips, new_arriving_trips} ->
           case audio do
+            # TODO: Add a check for whether high-confidence crowding info is present and whether it has already been announced with an approaching message
             %Audio.TrainIsArriving{trip_id: trip_id} when not is_nil(trip_id) ->
               if audio.trip_id in sign.announced_arrivals do
                 {new_audios, new_approaching_trips, new_arriving_trips}
@@ -154,6 +155,7 @@ defmodule Signs.Utilities.Audio do
                  [audio.trip_id | new_arriving_trips]}
               end
 
+            # TODO: Start tracking trip_ids where we announce high-confidence crowding info with Approaching
             %Audio.Approaching{trip_id: trip_id} when not is_nil(trip_id) ->
               if audio.trip_id in sign.announced_approachings do
                 {new_audios, new_approaching_trips, new_arriving_trips}