canvasManagement/Management.Web/Shared/Semester/Day.razor

@inject AssignmentDragContainer dragContainer
@inject CoursePlanner configurationManagement

@inject CoursePlanner planner

@code 
{
  [Parameter, EditorRequired]
  public DateTime? date { get; set; } =
  default!; 
  
  private bool isWeekDay {
    get => date?.DayOfWeek != null;
  }
  private bool dragging {get; set;} = false;
  private string calculatedClass
  {
    get
    {
      var baseClasses = "col border rounded rounded-3 p-2 pb-4 m-1 "; 
      if(dragging)
        return baseClasses + " bg-secondary text-light ";

      if (isWeekDay)
      {
        DayOfWeek? weekDay = date?.DayOfWeek;
        DayOfWeek notNullDay = weekDay ?? default;
        var dayInSemester = 
          planner.LocalCourse.DaysOfWeek.Contains(notNullDay) 
          && date < planner.LocalCourse.EndDate 
          && date > planner.LocalCourse.StartDate;

        var totalClasses = dayInSemester ? $"bg-light {baseClasses}" : baseClasses;

        return totalClasses;
      }
      else
      {
        return baseClasses;
      }
    }
  }
  void OnDragStart()
  {
      Console.WriteLine("on drag start");
  }

  async Task OnDrop()
  {
    Console.WriteLine("on drop");
    dragging = false;
    if(dragContainer.AssignmentBeingDragged == null){
      System.Console.WriteLine("no assignment in drop event");
      return;
    }

    Console.WriteLine(JsonSerializer.Serialize(dragContainer.AssignmentBeingDragged));
    dragContainer.AssignmentBeingDragged = null;
  }

  async Task OnDragEnter() {
    dragging = true;
  }
  async Task OnDragLeave() {
    dragging = false;
  }
} 

<div 
  class="@calculatedClass"
  @ondrop="@(() => OnDrop())"
  @ondragenter="OnDragEnter"
  @ondragleave="OnDragLeave"
  ondragover="event.preventDefault();"
  ondragstart="event.dataTransfer.setData('', event.target.id);"
>
  @(isWeekDay ? date?.Day : "")
</div>