R/Create.R

In vosonSML: Collecting Social Media Data and Generating Networks for Analysis

#' @title Create networks from social media data
#'
#' @description This function creates networks from social media data as produced from \code{\link{Collect}}.
#'   \code{Create} is the final step of the \code{\link{Authenticate}}, \code{\link{Collect}} and \code{Create}
#'   workflow.
#'
#'   There are four types of networks that can be created from collected data: \code{activity}, \code{actor},
#'   \code{twomode} or \code{semantic}.
#'
#'   For \code{activity} networks refer to \code{\link{Create.activity.twitter}}, \code{\link{Create.activity.youtube}}
#'   and \code{\link{Create.activity.reddit}} for parameters and usage.
#'
#'   For \code{actor} networks refer to \code{\link{Create.actor.twitter}}, \code{\link{Create.actor.youtube}} and
#'   \code{\link{Create.actor.reddit}}.
#'
#'   For \code{twomode} and \code{semantic} networks refer to \code{\link{Create.twomode.twitter}} and
#'   \code{\link{Create.semantic.twitter}} functions for parameters and usage respectively.
#'
#' @param datasource Collected social media data of class \code{"datasource"} and \code{socialmedia}.
#' @param type Character string. Type of network to be created, can be \code{"activity"}, \code{"actor"},
#'   \code{"twomode"} or \code{"semantic"}.
#' @param ... Optional parameters to pass to functions providied by supporting R packages that are used for social media
#'   network creation.
#'
#' @export
Create <- function(datasource, type, ...) {
  # searches the class list of datasource for matching method
  UseMethod("Create", type)
}

#' @export
Create.default <- function(datasource, type, ...) {
  # check datasource
  if (is.list(datasource) && ("tweets" %in% names(datasource))) {
    if (check_df_n(datasource$tweets) < 1) {
      stop("Datasource passed to Create is invalid or empty.", call. = FALSE)
    }
  } else {
    if (check_df_n(datasource) < 1) {
      stop("Datasource passed to Create is invalid or empty.", call. = FALSE)
    }
  }

  # check if network type is a character string
  if (!is.character(type)) {
    stop("Create network type should be a character string.", call. = FALSE)
  }

  # check if function exists for network type
  # todo: perhaps search create methods so this can be extensible
  func_name <- paste0("Create", ".", type)
  if (!exists(func_name, where = asNamespace("vosonSML"), mode = "function")) {
    stop("Unknown network type passed to create.", call. = FALSE)
  }

  # add social media type to value class list
  class(type) <- append(class(type), type)

  # call create again
  Create(datasource, type, ...)
}

#' @title Create activity networks from social media data
#'
#' @noRd
#' @method Create activity
#' @export
Create.activity <- function(datasource, type, ...) {
  msg <- f_verbose(check_dots("verbose", ...))

  UseMethod("Create.activity", datasource)
}

#' @noRd
#' @export
Create.activity.default <- function(datasource, type, ...) {
  stop("Unknown datasource passed to create activity network.", call. = FALSE)
}

#' @title Create actor network from social media data
#'
#' @noRd
#' @method Create actor
#' @export
Create.actor <- function(datasource, type, ...) {
  msg <- f_verbose(check_dots("verbose", ...))

  UseMethod("Create.actor", datasource)
}

#' @noRd
#' @export
Create.actor.default <- function(datasource, type, ...) {
  stop("Unknown datasource passed to create.", call. = FALSE)
}

#' @title Creates a semantic network from social media data
#'
#' @noRd
#' @method Create semantic
#' @export
Create.semantic <- function(datasource, type, ...) {
  msg <- f_verbose(check_dots("verbose", ...))

  UseMethod("Create.semantic", datasource)
}

#' @noRd
#' @export
Create.semantic.default <- function(datasource, type, ...) {
  stop("Unknown datasource passed to create semantic network.", call. = FALSE)
}

#' @title Create 2-mode networks from social media data
#'
#' @noRd
#' @method Create twomode
#' @export
Create.twomode <- function(datasource, type, ...) {
  UseMethod("Create.twomode", datasource)
}

#' @noRd
#' @export
Create.twomode.default <- function(datasource, type, ...) {
  stop("Unknown datasource passed to create twomode network.", call. = FALSE)
}