R/create_schedule.R

In derek-damron/budgetr: Easy budgeting in R

#' Creates a budget schedule
#'
#' \code{create_schedule} returns a budget schedule.
#'
#' @param ... A series of budget items separated by commas or a single list of budget items.
#' @return The output of \code{create_schedule} is a budget item.
#' @export
#' @examples
#' # Create a paycheck item
#' paycheck <- create_item( name = "Paycheck"
#'                        , amount = 1000
#'                        , day = "2016-01-01"
#'                        , recurring = "monthly"
#'                        )
#' # Create a rent item
#' rent <- create_item( name = "Rent"
#'                    , amount = -500
#'                    , day = "2016-01-05"
#'                    , recurring = "monthly"
#'                    )
#'
#' # Create a schedule
#' my_schedule <- create_schedule(paycheck, rent)
#' # Inspect
#' my_schedule
#'
#' # Using all items in the current environment
#' my_schedule <- create_schedule(get_items())
#' # Inspect
#' my_schedule

create_schedule <- function(...) {
    # Check that something was provided
    if (missing(...)) {
        stop("Please provide at least one budget item", call.=FALSE)
    }

    # Convert ... to a list of items
    items <- list(...)

    # Remove the double list structure if ... was a list rather than separate items
    if (!is.item(items[[1]])) {
        items <- items[[1]]
    }

    # Check that all args are items
    items_check <- sapply(items, is.item)
    if (any(!items_check)) {
        stop("At least one of the objects provided isn't a budget item", call.=FALSE)
    }

    # Create schedule
    schedule <- items

    # Objectify!
    class(schedule) <- c("schedule", "list")
    schedule
}