Added Unit Tests for external ephemeris formats testing event detectors

src/test/java/org/orekit/files/general/OrekitEphemerisFileTest.java

 package org.orekit.files.general;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
 import java.nio.file.Files;
+import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -13,6 +16,8 @@ import org.junit.Test;
 import org.orekit.Utils;
 import org.orekit.bodies.CelestialBody;
 import org.orekit.bodies.CelestialBodyFactory;
+import org.orekit.bodies.GeodeticPoint;
+import org.orekit.bodies.OneAxisEllipsoid;
 import org.orekit.errors.OrekitException;
 import org.orekit.files.ccsds.OEMParser;
 import org.orekit.files.ccsds.OEMWriter;
@@ -20,11 +25,20 @@ import org.orekit.files.general.EphemerisFile.EphemerisSegment;
 import org.orekit.files.general.OrekitEphemerisFile.OrekitSatelliteEphemeris;
 import org.orekit.frames.Frame;
 import org.orekit.frames.FramesFactory;
+import org.orekit.frames.TopocentricFrame;
+import org.orekit.orbits.CartesianOrbit;
 import org.orekit.orbits.KeplerianOrbit;
 import org.orekit.orbits.PositionAngle;
+import org.orekit.propagation.Propagator;
 import org.orekit.propagation.SpacecraftState;
+import org.orekit.propagation.analytical.Ephemeris;
 import org.orekit.propagation.analytical.KeplerianPropagator;
+import org.orekit.propagation.events.ElevationDetector;
+import org.orekit.propagation.events.EventsLogger;
+import org.orekit.propagation.events.EventsLogger.LoggedEvent;
 import org.orekit.time.AbsoluteDate;
+import org.orekit.utils.Constants;
+import org.orekit.utils.IERSConventions;
 import org.orekit.utils.TimeStampedPVCoordinates;
 
 public class OrekitEphemerisFileTest {
@@ -70,7 +84,7 @@ public class OrekitEphemerisFileTest {
                 mu);
         KeplerianPropagator propagator = new KeplerianPropagator(initialOrbit);
 
-        final double propagationDurationSeconds = 3600.0;
+        final double propagationDurationSeconds = 86400.0;
         final double stepSizeSeconds = 60.0;
         List<SpacecraftState> states = new ArrayList<SpacecraftState>();
 
@@ -86,6 +100,8 @@ public class OrekitEphemerisFileTest {
         new OEMWriter().write(tempOemFile, ephemerisFile);
 
         EphemerisFile ephemerisFromFile = new OEMParser().parse(tempOemFile);
+        Files.delete(Paths.get(tempOemFile));
+        
         EphemerisSegment segment = ephemerisFromFile.getSatellites().get(satId).getSegments().get(0);
         assertEquals(states.get(0).getDate(), segment.getStart());
         assertEquals(states.get(states.size() - 1).getDate(), segment.getStop());
@@ -93,7 +109,7 @@ public class OrekitEphemerisFileTest {
         assertEquals(frame, segment.getFrame());
         assertEquals(body.getName().toUpperCase(), segment.getFrameCenterString());
         assertEquals(body.getGM(), segment.getMu(), muTolerance);
-        for(int i = 0 ; i < states.size() ; i++) {
+        for (int i = 0; i < states.size(); i++) {
             TimeStampedPVCoordinates expected = states.get(i).getPVCoordinates();
             TimeStampedPVCoordinates actual = segment.getCoordinates().get(i);
             assertEquals(expected.getDate(), actual.getDate());
@@ -101,6 +117,70 @@ public class OrekitEphemerisFileTest {
             assertEquals(0.0, Vector3D.distance(expected.getVelocity(), actual.getVelocity()), velocityTolerance);
         }
 
+        // test ingested ephemeris generates access intervals
+        final OneAxisEllipsoid parentShape = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS,
+                Constants.WGS84_EARTH_FLATTENING, FramesFactory.getITRF(IERSConventions.IERS_2010, true));
+        final double latitude = 0.0;
+        final double longitude = 0.0;
+        final double altitude = 0.0;
+        final GeodeticPoint point = new GeodeticPoint(latitude, longitude, altitude);
+        final TopocentricFrame topo = new TopocentricFrame(parentShape, point, "testPoint1");
+        final ElevationDetector elevationDetector = new ElevationDetector(topo);
+        final EphemerisSegmentPropagator ephemerisSegmentPropagator = new EphemerisSegmentPropagator(segment);
+        final EventsLogger lookupLogger = new EventsLogger();
+        ephemerisSegmentPropagator.addEventDetector(lookupLogger.monitorDetector(elevationDetector));
+
+        final EventsLogger referenceLogger = new EventsLogger();
+        propagator.clearEventsDetectors();
+        propagator.addEventDetector(referenceLogger.monitorDetector(elevationDetector));
+
+        propagator.propagate(segment.getStart(), segment.getStop());
+        ephemerisSegmentPropagator.propagate(segment.getStart(), segment.getStop());
+
+        assertTrue(referenceLogger.getLoggedEvents().size() > 0);
+        assertEquals(referenceLogger.getLoggedEvents().size(), lookupLogger.getLoggedEvents().size());
+        for (int i = 0; i < referenceLogger.getLoggedEvents().size(); i++) {
+            LoggedEvent reference = referenceLogger.getLoggedEvents().get(i);
+            LoggedEvent actual = referenceLogger.getLoggedEvents().get(i);
+            assertEquals(reference.getState().getDate(), actual.getState().getDate());
+        }
+
+        final double dateEpsilon = 1e-9;
+        final Propagator embeddedPropagator = segment.getPropagator();
+        final EventsLogger embeddedPropLogger = new EventsLogger();
+        embeddedPropagator.addEventDetector(embeddedPropLogger.monitorDetector(elevationDetector));
+        embeddedPropagator.propagate(segment.getStart(), segment.getStop());
+        assertEquals(referenceLogger.getLoggedEvents().size(), embeddedPropLogger.getLoggedEvents().size());
+        for (int i = 0; i < referenceLogger.getLoggedEvents().size(); i++) {
+            LoggedEvent reference = referenceLogger.getLoggedEvents().get(i);
+            LoggedEvent actual = embeddedPropLogger.getLoggedEvents().get(i);
+            assertEquals(0.0, Math.abs(reference.getState().getDate().durationFrom(actual.getState().getDate())),
+                    dateEpsilon);
+                 
+        }
+
+        final List<SpacecraftState> readInStates = new ArrayList<SpacecraftState>();
+        segment.getCoordinates().forEach(c -> {
+            try {
+                readInStates.add(new SpacecraftState(new CartesianOrbit(c, frame, mu)));
+            } catch (IllegalArgumentException | OrekitException e) {
+                e.printStackTrace();
+            }
+        });
+        
+        final int interpolationPoints = 5;
+        Ephemeris directEphemProp = new Ephemeris(readInStates, interpolationPoints);
+        final EventsLogger directEphemPropLogger = new EventsLogger();
+        directEphemProp.addEventDetector(directEphemPropLogger.monitorDetector(elevationDetector));
+        directEphemProp.propagate(segment.getStart(), segment.getStop());
+        assertEquals(referenceLogger.getLoggedEvents().size(), directEphemPropLogger.getLoggedEvents().size());
+        for (int i = 0; i < referenceLogger.getLoggedEvents().size(); i++) {
+            LoggedEvent reference = referenceLogger.getLoggedEvents().get(i);
+            LoggedEvent actual = directEphemPropLogger.getLoggedEvents().get(i);
+            assertEquals(0.0, Math.abs(reference.getState().getDate().durationFrom(actual.getState().getDate())),
+                    dateEpsilon);
+        }
+
     }
 
 }