feature/add to now support

src/Enums/RelativityDirection.cs

@@ -0,0 +1,8 @@
+namespace moment.net.Enums
+{
+    internal enum RelativityDirection
+    {
+        From,
+        To
+    }
+}

src/RelativeTime.cs

@@ -1,24 +1,28 @@
 using System;
+using moment.net.Enums;
 
 namespace moment.net
 {
     public static class RelativeTime
     {
-        private const int _daysInAWeek = 7;
-        private const double _daysInAYear = 365.2425; // see https://en.wikipedia.org/wiki/Gregorian_calendar
-        private const double _daysInAMonth = _daysInAYear / 12;
+        private const double DaysInAYear = 365.2425; // see https://en.wikipedia.org/wiki/Gregorian_calendar
+        private const double DaysInAMonth = DaysInAYear / 12;
 
         public static string FromNow(this DateTime This)
         {
-            if (This.Kind == DateTimeKind.Utc)
-            {
-                return TimeFromTimeSpan(DateTime.UtcNow - This);
-            }
+            return This.Kind == DateTimeKind.Utc
+                ? ParseFromPastTimeSpan(DateTime.UtcNow - This)
+                : ParseFromPastTimeSpan(DateTime.Now - This);
+        }
 
-            return TimeFromTimeSpan(DateTime.Now - This);
+        public static string ToNow(this DateTime This)
+        {
+            return This.Kind == DateTimeKind.Utc
+                ? ParseFromFutureTimeSpan(This - DateTime.UtcNow)
+                : ParseFromFutureTimeSpan(This - DateTime.Now);
         }
 
-        private static string TimeFromTimeSpan(TimeSpan timeSpan)
+        private static string ParseFromPastTimeSpan(TimeSpan timeSpan)
         {
             var totalTimeInSeconds = timeSpan.TotalSeconds;
 
@@ -70,7 +74,7 @@ private static string TimeFromTimeSpan(TimeSpan timeSpan)
 
             if (totalTimeInDays > 45 && totalTimeInDays <= 319)
             {
-                return $"{Math.Ceiling(totalTimeInDays / _daysInAMonth)} months ago";
+                return $"{Math.Ceiling(totalTimeInDays / DaysInAMonth)} months ago";
             }
 
             if (totalTimeInDays > 319 && totalTimeInDays <= 547)
@@ -80,10 +84,80 @@ private static string TimeFromTimeSpan(TimeSpan timeSpan)
 
             if (totalTimeInDays > 547)
             {
-                return $"{Math.Ceiling(totalTimeInDays / _daysInAYear)} years ago";
+                return $"{Math.Ceiling(totalTimeInDays / DaysInAYear)} years ago";
+            }
+
+            throw new ArgumentOutOfRangeException(nameof(timeSpan), timeSpan,
+                "The time span sent could not be parsed.");
+        }
+
+        private static string ParseFromFutureTimeSpan(TimeSpan timeSpan)
+        {
+            var totalTimeInSeconds = timeSpan.TotalSeconds;
+
+            if (totalTimeInSeconds <= 44.0)
+            {
+                return "in a few seconds";
+            }
+
+            if (totalTimeInSeconds > 44.0 && totalTimeInSeconds <= 89.0)
+            {
+                return "in a minute";
+            }
+
+            var totalTimeInMinutes = timeSpan.TotalMinutes;
+
+            if (totalTimeInSeconds > 89 && totalTimeInMinutes <= 44)
+            {
+                return $"in {Math.Ceiling(totalTimeInMinutes)} minutes";
+            }
+
+            if (totalTimeInMinutes > 44 && totalTimeInMinutes <= 89)
+            {
+                return "in an hour";
+            }
+
+            var totalTimeInHours = timeSpan.TotalHours;
+
+            if (totalTimeInMinutes > 89 && totalTimeInHours <= 21)
+            {
+                return $"in {Math.Ceiling(totalTimeInHours)} hours";
+            }
+
+            if (totalTimeInHours > 21 && totalTimeInHours <= 35)
+            {
+                return "in a day";
+            }
+
+            var totalTimeInDays = timeSpan.TotalDays;
+
+            if (totalTimeInHours > 35 && totalTimeInDays <= 25)
+            {
+                return $"in {Math.Ceiling(totalTimeInDays)} days";
+            }
+
+            if (totalTimeInDays > 25 && totalTimeInDays <= 45)
+            {
+                return "in a month";
+            }
+
+            if (totalTimeInDays > 45 && totalTimeInDays <= 319)
+            {
+                return $"in {Math.Ceiling(totalTimeInDays / DaysInAMonth)} months";
+            }
+
+            if (totalTimeInDays > 319 && totalTimeInDays <= 547)
+            {
+                return "in a year";
+            }
+
+            if (totalTimeInDays > 547)
+            {
+                return $"in {Math.Ceiling(totalTimeInDays / DaysInAYear)} years";
             }
-
-            throw new ArgumentOutOfRangeException(nameof(timeSpan), timeSpan, "The time span sent could not be parsed.");
+
+            throw new ArgumentOutOfRangeException(nameof(timeSpan), timeSpan,
+                "in The time span sent could not be parsed.");
         }
     }
 }

tests/RelativeTime.Tests.cs

@@ -1,9 +1,11 @@
 using System;
+using System.Diagnostics.CodeAnalysis;
 using NUnit.Framework;
 using Shouldly;
 
 namespace moment.net.Tests
 {
+    [ExcludeFromCodeCoverage]
     public class RelativeTimeTests
     {
         [Test]
@@ -96,5 +98,96 @@ public void MultipleYearsTest()
             var dateTime = DateTime.UtcNow.AddDays(-3650);
             dateTime.FromNow().ShouldBe("10 years ago");
         }
+
+        [Test]
+        public void AFewSecondsInTheFutureTest()
+        {
+            var aFewSecondsAgo = DateTime.UtcNow.AddSeconds(20);
+            aFewSecondsAgo.ToNow().ShouldBe("in a few seconds");
+        }
+
+        [Test]
+        public void MoreSecondsInTheFutureTest()
+        {
+            var largeSecondsAgo = DateTime.UtcNow.AddSeconds(50);
+            largeSecondsAgo.ToNow().ShouldBe("in a minute");
+        }
+
+        [Test]
+        public void AFewMinutesInTheFutureTest()
+        {
+            var afewMinutesAgo = DateTime.Now.AddMinutes(1);
+            afewMinutesAgo.ToNow().ShouldBe("in a minute");
+        }
+
+        [Test]
+        public void MoreMinutesInTheFutureTest()
+        {
+            var minutesAgo = DateTime.Now.AddMinutes(15);
+            minutesAgo.ToNow().ShouldBe("in 15 minutes");
+        }
+
+        [Test]
+        public void ToHourTest()
+        {
+            var dateTime = DateTime.UtcNow.AddMinutes(65);
+            dateTime.ToNow().ShouldBe("in an hour");
+        }
+
+        [Test]
+        public void ToMultipleHoursTest()
+        {
+            var dateTime = DateTime.UtcNow.AddHours(20);
+            dateTime.ToNow().ShouldBe("in 20 hours");
+        }
+
+        [Test]
+        public void ToDayTest()
+        {
+            var dateTime = DateTime.UtcNow.AddHours(25);
+            dateTime.ToNow().ShouldBe("in a day");
+        }
+
+        [Test]
+        public void ToMultipleDaysTest()
+        {
+            var dateTime = DateTime.UtcNow.AddDays(4);
+            dateTime.ToNow().ShouldBe("in 4 days");
+        }
+
+        [Test]
+        public void ToMonthTest()
+        {
+            var dateTime = DateTime.UtcNow.AddDays(27);
+            dateTime.ToNow().ShouldBe("in a month");
+        }
+
+        [Test]
+        public void ToMultipleMonthsTest()
+        {
+            var dateTime = DateTime.UtcNow.AddDays(60);
+            dateTime.ToNow().ShouldBe("in 2 months");
+        }
+
+        [Test]
+        public void ToYearTest()
+        {
+            var dateTime = DateTime.UtcNow.AddDays(360);
+            dateTime.ToNow().ShouldBe("in a year");
+        }
+
+        [Test]
+        public void ToTwoYearsTest()
+        {
+            var dateTime = DateTime.UtcNow.AddDays(570);
+            dateTime.ToNow().ShouldBe("in 2 years");
+        }
+
+        [Test]
+        public void ToMultipleYearsTest()
+        {
+            var dateTime = DateTime.UtcNow.AddDays(3650);
+            dateTime.ToNow().ShouldBe("in 10 years");
+        }
     }
 }