Fixes a bug in EventStatistics

This patch ensures that the audio recording duration used by event statistics is always rounded down to the nearest second. There is a subtle conflict in logic later on in the event downloading  code that requires audio segments be rounded to the nearest second. If the recording duration is greater than 0.5, and the event ends at the end of the recording, then the requested media is rounded up to the next second, past the end of the recording. This patch prevents that error.

src/Acoustics.Shared/Extensions/DoubleExtensions.cs

@@ -48,5 +48,7 @@ public static double RoundToSignficantDigits(this double d, int digits)
             decimal scale = (decimal)Math.Pow(10, Math.Floor(Math.Log10((double)Math.Abs(dec))) + 1);
             return (double)(scale * Math.Round(dec / scale, digits, MidpointRounding.AwayFromZero));
         }
+
+        public static double Floor(this double d) => Math.Floor(d);
     }
 }

src/AnalysisPrograms/AcousticWorkbench.Orchestration/EventMetadataResolver.cs

@@ -188,7 +188,9 @@ private async Task<IEnumerable<RemoteSegmentWithData>> DownloadRemoteMetadata(
                 $"Metadata for audio recording media {audioRecordingId} retrieved, generating segments for associated events");
 
             // now generate the segments
-            var limit = audioRecording.DurationSeconds.AsRangeFromZero();
+            // we need to floor the duration to ensure later rounding does round past the limit of the recording
+            Log.Verbose($"Audio recording duration {audioRecording.DurationSeconds} will be floored");
+            var limit = audioRecording.DurationSeconds.Floor().AsRangeFromZero();
             var results = new List<RemoteSegmentWithData>(20);
             foreach (var importedEvent in events)
             {

src/AnalysisPrograms/EventStatistics/ImportedEvent.cs

@@ -10,6 +10,7 @@ namespace AnalysisPrograms.EventStatistics
     using System.Reflection;
     using System.Text;
     using System.Threading.Tasks;
+    using Acoustics.Shared;
     using AcousticWorkbench;
     using CsvHelper.Configuration;
     using log4net;
@@ -44,6 +45,15 @@ public bool IsValid()
                    && this.HighFrequencyHertz.HasValue);
         }
 
+        /// <summary>
+        /// Returns a JSON encoded string that describes this object.
+        /// </summary>
+        /// <returns>The string that describes this object.</returns>
+        public override string ToString()
+        {
+            return Json.SerialiseToString(this);
+        }
+
         public sealed class ImportedEventNameClassMap : CsvClassMap<ImportedEvent>
         {
             private static readonly PropertyInfo[] Properties = typeof(ImportedEvent).GetProperties();