#' Data
#'
#' Data encapsulation
#'
#' @field data List of
#' \itemize{
#'   \item time: vector of times
#'   \item serie: centered series
#'   \item level: corresponding levels
#'   \item exo: exogenous variables
#'   \item exo_hat: predicted exogenous variables
#' }
#'
#' @docType class
#' @importFrom R6 R6Class
#'
#' @export
Data = R6Class("Data",
	private = list(
		.data = "list"
	),
	public = list(
		initialize = function(...)
			initialize(self, private, ...)
		,
		getSize = function()
			getSize(private)
		,
		getStdHorizon = function()
			getStdHorizon(private)
		,
		append = function(new_time, new_centered_serie, new_level, new_exo, new_exo_hat)
			append(private, new_time, new_centered_serie, new_level, new_exo, new_exo_hat)
		,
		getTime = function(index)
			getTime(self, private, index)
		,
		getCenteredSerie = function(index)
			getCenteredSerie(self, private, index)
		,
		getLevel = function(index)
			getLevel(self, private, index)
		,
		getSerie = function(index)
			getSerie(self, private, index)
		,
		getExo = function(index)
			getExo(self, private, index)
		,
		getExoHat = function(index)
			getExoHat(self, private, index)
	)
)

##TODO: @param... @inheritParams...

#' Initialize empty Data object
initialize = function(o, private, ...)
{
	private$.data <<- if (hasArg("data")) list(...)$data else list()
	invisible(o)
}

#' Number of series in the dataset
getSize = function(private)
	length(private$.data)

#' 'Standard' horizon, from t+1 to midnight
getStdHorizon = function(private)
	24 - as.POSIXlt( private$.data[[1]]$time[1] )$hour + 1

#' Acquire a new vector of lists (time, centered_serie, level, exo, exo_hat)
append = function(private, new_time, new_centered_serie, new_level, new_exo_hat, new_exo)
{
	private$.data[[length(private$.data)+1]] <<- list("time"=new_time,
		"centered_serie"=new_centered_serie,"level"=new_level,"exo"=new_exo,"exo_hat"=new_exo_hat)
}

#' Time values at specified index
getTime = function(o, private, index)
{
	index = dateIndexToInteger(index, o)
	private$.data[[index]]$time
}

#' Centered serie values at specified index
getCenteredSerie = function(o, private, index)
{
	index = dateIndexToInteger(index, o)
	private$.data[[index]]$serie
}

#' Level of the serie at specified index
getCenteredSerie = function(o, private, index)
{
	index = dateIndexToInteger(index, o)
	private$.data[[index]]$level
}

#' Serie values (centered+level) at specified index
getCenteredSerie = function(o, private, index)
{
	index = dateIndexToInteger(index, o)
	private$.data[[index]]$serie + data[[index]]$level
}

#' Exogenous measures at specified index
getCenteredSerie = function(o, private, index)
{
	index = dateIndexToInteger(index, o)
	private$.data[[index]]$exo
}

#' Exogeous predictions at specified index
getCenteredSerie = function(o, private, index)
{
	index = dateIndexToInteger(index, o)
	private$.data[[index]]$exo_hat
}