Time estimation work

Core/DAL/DataService.cs

@@ -80,6 +80,16 @@ namespace LeafWeb.Core.DAL
 					select s).Max(s => s.DateTime));
 		}
 
+		public IEnumerable<LeafInput> GetLeafInputRecentlyCompleted(int count)
+		{
+			return
+				_db.LeafInputs
+					.Where(li => li.CurrentStatus == LeafInputStatusType.Complete)
+					.Take(count)
+					.ToList()
+					.Where(li => li.OutputErrorMessage == null);
+		}
+
 		public LeafInput GetLeafInput(int id)
 		{
 			return _db.LeafInputs.FirstOrDefault(li => li.Id == id);

Core/Utility/TimeInProgressEstimater.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using LeafWeb.Core.Entities;
 using MathNet.Numerics;
 
@@ -23,7 +24,15 @@ namespace LeafWeb.Core.Utility
 			_yData = yData.ToArray();
 		}
 
-		private Func<double, double> FitFunc => Fit.PolynomialFunc(_xData, _yData, 3);
+		private static Func<double, double> Positivize => i => i <= 0 ? 1 : i;
+
+		private IEnumerable<double> Div => _xData.Zip(_yData, (x, y) => y/x);
+
+		private Func<double, double> AverageFitFunc => i => Div.Average()*i;
+
+		private Func<double, double> LineFitFunc => Fit.LineFunc(_xData, _yData);
+
+		private Func<double, double> FitFunc => i => (Positivize(LineFitFunc(i)) + AverageFitFunc(i))/2;
 
 		public TimeSpan EstimateTimeInProgress(ILeafInput leafInput)
 		{
@@ -32,7 +41,10 @@ namespace LeafWeb.Core.Utility
 
 		public TimeSpan EstimateTimeInProgress(int inputFileCount)
 		{
-			return ConvertToTimeSpan(FitFunc(inputFileCount));
+			var estimate = FitFunc(inputFileCount);
+			if (estimate <= 0)
+				estimate = 1;
+			return ConvertToTimeSpan(estimate);
 		}
 
 		private static double ConvertFromTimeSpan(TimeSpan timeSpan)
@@ -42,16 +54,19 @@ namespace LeafWeb.Core.Utility
 
 		private static TimeSpan ConvertToTimeSpan(double estimate)
 		{
-			int int32;
+			return TimeSpan.FromSeconds(ConvertToInt32Guarded(estimate));
+		}
+
+		private static Func<double, int> ConvertToInt32Guarded => d =>
+		{
 			try
 			{
-				int32 = Convert.ToInt32(estimate);
+				return Convert.ToInt32(d);
 			}
 			catch (OverflowException)
 			{
-				int32 = int.MaxValue;
+				return int.MaxValue;
 			}
-			return TimeSpan.FromSeconds(int32);
-		}
+		};
 	}
 }