From 8d8bb8bf6dee732f03f12ba0c6c4fd2d77669510 Mon Sep 17 00:00:00 2001
From: Alex Mickelson <alexmickelson96@gmail.com>
Date: Wed, 4 Jan 2023 22:08:53 -0700
Subject: [PATCH] can calculate months

---
 Management.Test/Features/SemesterPlannerTests.cs | 14 ++++++++++++++
 Management/Features/Calendar/SemesterPlanner.cs  |  6 ++++--
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/Management.Test/Features/SemesterPlannerTests.cs b/Management.Test/Features/SemesterPlannerTests.cs
index cdd80ba..50fe494 100644
--- a/Management.Test/Features/SemesterPlannerTests.cs
+++ b/Management.Test/Features/SemesterPlannerTests.cs
@@ -31,6 +31,20 @@ public class SemesterPlannerTests
 
     var semester = new SemesterPlanner(canvasTerm);
 
+    semester.Months.Count().Should().Be(2);
+  }
+  [Test]
+  public void TestNewPlannerHandlesTermsThatWrapYears()
+  {
+    var canvasTerm = new EnrollmentTermModel(
+      Id: 1,
+      Name: "one",
+      StartAt: new DateTime(2022, 12, 1),
+      EndAt: new DateTime(2023, 1, 1)
+    );
+
+    var semester = new SemesterPlanner(canvasTerm);
+
     semester.Months.Count().Should().Be(2);
   }
 }
\ No newline at end of file
diff --git a/Management/Features/Calendar/SemesterPlanner.cs b/Management/Features/Calendar/SemesterPlanner.cs
index 7368612..af801a4 100644
--- a/Management/Features/Calendar/SemesterPlanner.cs
+++ b/Management/Features/Calendar/SemesterPlanner.cs
@@ -5,9 +5,11 @@ public class SemesterPlanner
   public IEnumerable<CalendarMonth> Months { get; }
   public SemesterPlanner(EnrollmentTermModel canvasTerm)
   {
-    var monthsInTerm = canvasTerm.EndAt?.Month - canvasTerm.StartAt?.Month
+    var monthsInTerm = 
+      1 + ((canvasTerm.EndAt?.Year - canvasTerm.StartAt?.Year) * 12) 
+        + canvasTerm.EndAt?.Month - canvasTerm.StartAt?.Month
       ?? throw new Exception($"Canvas Term must have a start and end date. Term: {canvasTerm.Id}, start: {canvasTerm.StartAt}, end: {canvasTerm.EndAt}");
 
-    Months = Enumerable.Range(1, monthsInTerm).Select(_ => new CalendarMonth());
+    Months = Enumerable.Range(0, monthsInTerm).Select(_ => new CalendarMonth());
   }
 }
\ No newline at end of file