i liked syncing more before i cared about order

Management/Features/Configuration/CoursePlannerExtensions.cs

@@ -0,0 +1,83 @@
+using CanvasModel.Assignments;
+using CanvasModel.Modules;
+using LocalModels;
+
+namespace Management.Planner;
+
+public static class CoursePlannerExtensions
+{
+  public static LocalCourse GeneralCourseCleanup(this LocalCourse incomingCourse)
+  {
+    var modulesWithUniqueAssignments = incomingCourse.Modules.Select(
+      module =>
+        module with
+        {
+          Assignments = module.Assignments.OrderBy(a => a.due_at).DistinctBy(a => a.id)
+        }
+    );
+
+    return incomingCourse with
+    {
+      Modules = modulesWithUniqueAssignments
+    };
+  }
+
+  public static LocalCourse deleteCanvasIdsThatNoLongerExist(
+    this LocalCourse localCourse,
+    IEnumerable<CanvasModule> canvasModules,
+    IEnumerable<CanvasAssignment> canvasAssignments
+  )
+  {
+    Console.WriteLine("checking canvas ids still exist");
+
+    var correctedModules = localCourse.Modules
+      .Select((m) => m.validateCanvasIds(canvasModules, canvasAssignments))
+      .ToArray();
+
+    return localCourse with
+    {
+      Modules = correctedModules
+    };
+  }
+
+  private static LocalModule validateCanvasIds(
+    this LocalModule module,
+    IEnumerable<CanvasModule> canvasModules,
+    IEnumerable<CanvasAssignment> canvasAssignments
+  )
+  {
+    var moduleIdInCanvas = canvasModules.FirstOrDefault(m => m.Id == module.CanvasId) != null;
+    var moduleWithAssignments = module with
+    {
+      Assignments = module.Assignments
+        .Select((a) => a.validateAssignmentForCanvasId(canvasAssignments))
+        .ToArray()
+    };
+
+    if (!moduleIdInCanvas)
+    {
+      Console.WriteLine(
+        $"no id in canvas for module, removing old canvas id: {moduleWithAssignments.Name}"
+      );
+      return moduleWithAssignments with { CanvasId = null };
+    }
+    return moduleWithAssignments;
+  }
+
+  private static LocalAssignment validateAssignmentForCanvasId(
+    this LocalAssignment assignment,
+    IEnumerable<CanvasAssignment> canvasAssignments
+  )
+  {
+    var assignmentIdInCanvas =
+      canvasAssignments.FirstOrDefault(ca => ca.Id == assignment.canvasId) != null;
+    if (!assignmentIdInCanvas)
+    {
+      Console.WriteLine(
+        $"no id in canvas for assignment, removing old canvas id: {assignment.name}"
+      );
+      return assignment with { canvasId = null };
+    }
+    return assignment;
+  }
+}