FreeBusyStatus GetFreeBusyStatus(IDateTime dt) does not handle all day events.

[johnwhoffman]

I found this issue in our code and repro-ed in a unit test you can add to your FreeBusy unit test class.
GetFreeBusyStatus() should return Busy for all the asserts but always returns Free.
I believe the issue is GetFreeBusy relies on Period.Contains() to determine if there is an overlap.
foreach (var fbe in Entries.Where(fbe => fbe.Contains(dt) && status < fbe.Status))
I think there needs to be logic that handles all day events which always have T000000

BEGIN:VCALENDAR
PRODID:-//github.com/rianjs/ical.net//NONSGML ical.net 2.2//EN
VERSION:2.0
BEGIN:VEVENT
DTEND:20161228T000000
DTSTAMP:20161229T151857Z
DTSTART:20161228T000000
RRULE:FREQ=DAILY;BYDAY=MO,TU,WE,TH,FR
SEQUENCE:0
SUMMARY:00:15:00
UID:ca7053f9-7923-4701-8e02-8f677a6c5120
END:VEVENT
END:VCALENDAR

[TestMethod, TestCategory("FreeBusy")]
public void GetFreeBusyStatus2()
{
    var cal = new Calendar();

    var evt = cal.Create<Event>();
    evt.Summary = "Test event";
    evt.Start = new CalDateTime(2010, 10, 1, 0, 0, 0);
    var oneDayBefore = evt.Start.Subtract(new TimeSpan(1, 0, 0, 0));
    var oneDayAfter = evt.Start.Add(new TimeSpan(1, 0, 0, 0));
    evt.End = new CalDateTime(2010, 10, 1, 0, 0, 0);

    var freeBusy = cal.GetFreeBusy(oneDayBefore, oneDayAfter);

    var orderedEntries = freeBusy.Entries.OrderBy(p => p.StartTime).ToList();

    foreach (var entry in orderedEntries)
    {
        System.Diagnostics.Trace.WriteLine($"IFreeBusyEntry.Start: {entry.StartTime}, IFreeBusyEntry.End: {entry.EndTime}, IFreeBusyEntry.Status: {entry.Status}");
    }
    Assert.AreEqual(FreeBusyStatus.Free, freeBusy.GetFreeBusyStatus(new CalDateTime(2010, 10, 1, 7, 59, 59)));
    Assert.AreEqual(FreeBusyStatus.Busy, freeBusy.GetFreeBusyStatus(new CalDateTime(2010, 10, 1, 8, 0, 0)));
    Assert.AreEqual(FreeBusyStatus.Busy, freeBusy.GetFreeBusyStatus(new CalDateTime(2010, 10, 1, 8, 59, 59)));
    Assert.AreEqual(FreeBusyStatus.Free, freeBusy.GetFreeBusyStatus(new CalDateTime(2010, 10, 1, 9, 0, 0)));
}

[rianjs]

Does #161 have any relevance here?

[johnwhoffman]

Does not seem to be related but I am not up to speed on all your unit test patterns.
AFAICT the all day event concept does not seem to be tested in your test suites.
Please correct me if I have missed something.

[rianjs]

Oh, I was responding to

I believe the issue is GetFreeBusy relies on Period.Contains() to determine if there is an overlap.

Contains vs Overlaps is talked about in that thread. A closer reading suggests this is different.

[johnwhoffman]

Here is the fix I am adding to our copy of the code.
Let me know if you find issues with this.
Thanks for your efforts!

` public virtual FreeBusyStatus GetFreeBusyStatus(IDateTime dt)
{
var status = FreeBusyStatus.Free;
if (dt == null)
{
return status;
}

  foreach (FreeBusyEntry  fbe in Entries)
  {
    if (fbe.Contains(dt))
    {
      if (status < fbe.Status)
      {
        status = fbe.Status;
      }
    }
    else if (fbe.EndTime.CompareTo(fbe.StartTime) == 0 && dt.GreaterThan(fbe.StartTime))
    {
      // all day event
      status = fbe.Status;
    }
  }
  return status;
}`