/// <summary>
/// Master constructor for the "top level" of our application
/// TODO: create a factory method if initialization becomes complicated. Not needed now
/// </summary>
public FlightProcessor()
{
airports = AirportCollection.LoadFromFile(AirportsFilePath);
ProcessingType = "file";
EventsQueue = new ConcurrentQueue <AdsbEvent>();
FlightsQueue = new ConcurrentQueue <Flight>();
MainEventProcessor = new EventProcessor(FlightsQueue, airports);
}
/// <summary>
/// Master constructor is used for unit tests. Clean it up later
/// </summary>
public FlightProcessor(string airportFile, string eventFile, string debugAirplane)
{
airports = AirportCollection.LoadFromFile(airportFile);
ProcessingType = "file";
EventsQueue = new ConcurrentQueue <AdsbEvent>();
FlightsQueue = new ConcurrentQueue <Flight>();
MainEventProcessor = new EventProcessor(FlightsQueue, airports);
AdsbEventsFilePath = eventFile;
DEBUG_FLIGHT = debugAirplane;
}
private static void Execute()
{
// Load the input data
AirportCollection airports = AirportCollection.LoadFromFile(AirportsFilePath);
AdsbEventCollection events = AdsbEventCollection.LoadFromFile(AdsbEventsFilePath);
// Create collection of identifiable flights
FlightCollection flights = CalculateFlights(airports, events);
// Write the output data
flights.WriteToFile(OutputFilePath);
}
private static void Execute()
{
// Load the airports
AirportCollection airports = AirportCollection.LoadFromFile(AirportsFilePath);
}
private static void Execute()
{
// Load the airports
AirportCollection airports = AirportCollection.LoadFromFile(AirportsFilePath);
var fileLines = System.IO.File.ReadAllLines(AdsbEventsFilePath);
Dictionary <string, List <AdsbEvent> > airplanes = new Dictionary <string, List <AdsbEvent> >();
foreach (var line in fileLines)
{
string airplaneId = Events.AdsbEvent.FromJson(line).Identifier;
if (airplanes.ContainsKey(airplaneId))
{
airplanes[airplaneId].Add(Events.AdsbEvent.FromJson(line));
}
else
{
List <AdsbEvent> tmpEventList = new List <AdsbEvent>()
{
Events.AdsbEvent.FromJson(line)
};
airplanes.Add(Events.AdsbEvent.FromJson(line).Identifier, tmpEventList);
}
}
System.IO.StreamWriter outFile = new System.IO.StreamWriter(OutputFilePath);
foreach (var key in airplanes.Keys)
{
// debug output
// System.Console.WriteLine(key);
// setting defaults
DateTime prevTime = DateTime.Parse("1/01/2020 12:00:00 AM");
GeoCoordinate prevAirportLocation = null;
Airport prevAirport = null;
Flight flight = new Flight();
flight.AircraftIdentifier = key;
foreach (var adsbEventEntry in airplanes[key])
{
// create a geolocation based on airplane adsb event coords
string latLong = adsbEventEntry.Latitude.ToString() + "," + adsbEventEntry.Longitude.ToString();
GeoCoordinate airplaneLocation = GeoCoordinate.FromLatitudeAndLongitudeString(latLong);
// get closest airport based on current airplane location
Airport tempAirport = airports.GetClosestAirport(airplaneLocation);
// create airport geolocation
string airportLatLong = tempAirport.Latitude.ToString() + "," + tempAirport.Longitude.ToString();
GeoCoordinate airportLocation = GeoCoordinate.FromLatitudeAndLongitudeString(airportLatLong);
// In order for an event to be a landing/takeoff:
// 1. geolocation within 5 miles of an airport (Flight safety, no unregistered aircraft within 5 miles of an airport)
// 2. altitude diff within 500 feet (safety altitude)
// 3. take off and landing speed < 200 mph
// In order for an airport to have a takeoff for this airplane:
// 1. The timestamp reads must have a difference > 30 mins
// Airplane heading and speed is not always present in adsbevent data, which means we can't rely on it to determine landing vs takeoff
double tempDist = airplaneLocation.GetDistanceTo(airportLocation);
if (tempDist < 5)
{
if (adsbEventEntry.Altitude != null && (adsbEventEntry.Altitude - tempAirport.Elevation <= 500) && adsbEventEntry.Speed != null && adsbEventEntry.Speed <= 200)
{
//did some reasearch, it looks like it takes the crew around 30-60 mins to get the plane checked again for next flight
if (adsbEventEntry.Timestamp - prevTime > TimeSpan.Parse("00:30:00"))
{
// logic for arrivals and departures
if (prevAirportLocation != null && prevAirportLocation != airportLocation)
{
//only departure is added w/ previous timestamp
flight.DepartureTime = prevTime;
flight.DepartureAirport = prevAirport.Identifier;
}
else if (prevAirportLocation == airportLocation)
{
//arrival is added w/ previous timestamp
flight.ArrivalTime = prevTime;
flight.ArrivalAirport = prevAirport.Identifier;
}
}
prevAirportLocation = airportLocation;
prevTime = adsbEventEntry.Timestamp;
prevAirport = tempAirport;
}
}
//record flights if arrival time is populated
if (flight.ArrivalAirport != null)
{
outFile.WriteLine(flight.ToString());
flight = new Flight();
flight.AircraftIdentifier = key;
}
}
}
outFile.Close();
}
private static void Execute()
{
// Process data files
var airports = AirportCollection.LoadFromFile(AirportsFilePath);
var adsbEvents = LoadFromFile(AdsbEventsFilePath);
Console.WriteLine($"Loaded {airports.Count} airports and {adsbEvents.Count} events");
// Sort events by aircraft
var allAircraft = new Dictionary <string, Aircraft>();
adsbEvents.ForEach((adsbEvent) =>
{
if (allAircraft.TryGetValue(adsbEvent.Identifier, out Aircraft aircraft))
{
aircraft.AdsbEvents.Add(adsbEvent);
}
else
{
allAircraft.Add(adsbEvent.Identifier,
new Aircraft(adsbEvent.Identifier, new List <AdsbEvent>()
{
adsbEvent
}));
}
});
Console.WriteLine($"Identified {allAircraft.Count} aircraft");
// Find potential flights
var flights = new List <Flight>();
allAircraft.Select(kv => kv.Value).ToList().ForEach((aircraft) =>
{
var flight = new Flight()
{
AircraftIdentifier = aircraft.AircraftIdentifier
};
// Filter out events without coordinates
var aircraftEvents = aircraft.AdsbEvents
.Where(adsbEvent => adsbEvent.Latitude != null && adsbEvent.Longitude != null)
.OrderBy(adsbEvent => adsbEvent.Timestamp);
// Implement a sliding window by analyzing the altitude data
// This could also be implemented by analyzing the speed data, but the altitude data is
// more consistent
var events = aircraftEvents.Where(adsbEvent => adsbEvent.Altitude != null);
var step = 10;
var sampleSize = 25;
var previousTrend = Trend.Unknown;
// Check the start events for departure
var startSample = events.Take(sampleSize);
if (startSample.First().Altitude < startSample.Last().Altitude)
{
flight.DepartureTime = events.First().Timestamp;
flight.DepartureAirport = airports.GetClosestAirport(events.First().GeoCoordinate).Identifier;
}
// Check the middle events for additional flights
for (var i = 0; i < events.Count() - sampleSize; i += step)
{
var sample = events.Skip(i).Take(sampleSize);
var currentTrend = GuessTrend(sample.Select(adsbEvent => adsbEvent.Altitude.Value));
// If the aircraft's altitude trend changes from decreasing to increasing below the altitude threshold,
// assume that it's started a new flight
if (previousTrend == Trend.Decrease &&
currentTrend == Trend.Increase &&
sample.First().Altitude < MAX_ALTITUDE)
{
var airport = airports.GetClosestAirport(sample.First().GeoCoordinate);
// If there isn't an airport nearby, the airplane may have made an unexpected descent and ascent
if (airport == null)
{
continue;
}
// Check if the aircraft is flying over the airport
if (Math.Abs(airport.Elevation - sample.First().Altitude.Value) >= GROUND_TOLERANCE)
{
continue;
}
flight.ArrivalTime = sample.First().Timestamp;
flight.ArrivalAirport = airport.Identifier;
flights.Add(flight);
flight = new Flight
{
AircraftIdentifier = aircraft.AircraftIdentifier,
DepartureTime = sample.Last().Timestamp,
DepartureAirport = airports.GetClosestAirport(sample.Last().GeoCoordinate).Identifier
};
}
previousTrend = currentTrend;
}
// Check the end events for arrival
var endSample = events.TakeLast(sampleSize);
if (endSample.First().Altitude > endSample.Last().Altitude)
{
flight.ArrivalTime = events.Last().Timestamp;
flight.ArrivalAirport = airports.GetClosestAirport(events.Last().GeoCoordinate).Identifier;
}
if (flight.DepartureAirport != null || flight.ArrivalAirport != null)
{
flights.Add(flight);
}
});
Console.WriteLine($"Identified {flights.Count} potential flights");
WriteResults(flights);
}