public async Task <ActionResult> ReorderTodos([FromRoute] int id, [FromRoute] int newOrder)
{
var request = new ReorderTodoCommand(User.Identity?.Name, id, newOrder);
var response = await _mediator.Send(request);
return(response.Match <ActionResult>(
ok => Ok(),
notFound => NotFound()
));
}
public async Task <OneOf <Ok, NotFound> > Handle(ReorderTodoCommand request, CancellationToken cancellationToken)
{
var userTodo = await _todosRepository
.GetAsync(todo => todo.Id == request.Id && todo.UserLogin == request.UserLogin);
if (userTodo == null)
{
return(new NotFound());
}
var todos = await _todosRepository.Query()
.Where(todo => todo.UserLogin == request.UserLogin)
.OrderBy(todo => todo.Order)
.ToListAsync(cancellationToken);
if (!todos.Any())
{
return(new NotFound());
}
var prevOrder = request.NewOrder > 0 ?
todos[request.NewOrder - 1].Order : 0;
var nextOrder = request.NewOrder < todos.Count ?
todos[request.NewOrder].Order : (todos.Count + 1) * 1024;
var deltaOrder = nextOrder - prevOrder;
userTodo.Order = prevOrder + deltaOrder / 2;
if (deltaOrder <= 2)
{
for (var i = 0; i < todos.Count; i++)
{
todos[i].Order = (i + 1) * 1024;
}
}
await _todosRepository.SaveChangesAsync();
return(new Ok());
}
