#' @include Forecaster.R
#'
#' @title Level Forecaster
#'
#' @description Return flat serie of last observed level. Inherits \code{\link{ShapeForecaster}}
LevelForecaster = setRefClass(
	Class = "LevelForecaster",
	contains = "Forecaster",

	methods = list(
		initialize = function(...)
		{
			callSuper(...)
		},
		predict = function(today, memory, horizon, ...)
		{
			#return last day level
			first_day = max(1, today-memory)
			same_day = ifelse(hasArg("same_day"), list(...)$same_day, TRUE)
			index = today - ifelse(same_day,6,0)
			repeat
			{
				{
					last_serie = data$getSerie(index)[1:horizon]
					index = index - ifelse(same_day,7,1)
				};
				#TODO: next test is too strict
				if (!any(is.na(last_serie)))
					return (rep(mean(last_serie), horizon));
				if (index < first_day)
					return (NA)
			}
		}
	)
)