R/app.R

In lbraun/spud: Classes and Methods for Spatial Usage Data

#' App
#'
#' This class represents a spatial app and its associated usage data.
#'
#' @section Usage:
#' \preformatted{
#' app = App$new("My app", x)
#'
#' print(app)
#'
#' app$users()
#' app$user_count()
#' app$get_user(user_id)
#' app$actions_map(flavor = "leaflet")
#' app$first_actions_map()
#' }
#'
#' @section Arguments:
#' \describe{
#'   \item{name}{Character scalar, the name of the app.}
#'   \item{usage_data}{An sf object, representing the usage data for the app.}
#' }
#'
#' @section Details:
#' \code{$new()} sets up the class with two properties: name and usage_data
#'
#' \code{$print()} prints out some basic identifying information about the app.
#'
#' \code{$users()} returns a vector containing the unique ids of the app's users.
#'
#' \code{$user_count()} returns a count of the app's users.
#'
#' \code{$get_user(user_id)} returns an object of class User. This object represents the user that
#'    matches the given id.
#'
#' \code{$actions_map(flavor = "leaflet")} draws a map showing the spatial distribution of the app's
#'    usage, color coded by action. Choose either the "leaflet" or "mapview" version of the map
#'    using the flavor parameter.
#'
#' \code{$first_actions_map()} draws a map showing locations where users tried the app for the first
#'    time.
#'
#' @importFrom R6 R6Class
#' @name App
#' @examples
#' x = read.spud("dummy_data.csv")
#' app = App$new("My app", x)
#' app$actions_map(flavor = "mapview")
NULL

#' @export
App = R6::R6Class("App",
  public = list(
    name = "character",
    usage_data = "sf",

    initialize = function(name = NA, usage_data = NA) {
      self$name = name
      self$usage_data = usage_data
    },

    print = function(...) {
      cat("<App> ", self$name, ", an app with ", self$user_count(), " users\n", sep = "")
      invisible(self)
    },

    users = function() {
      unique(self$usage_data$user)
    },

    user_count = function() {
      length(self$users())
    },

    get_user = function(user_id) {
      user_data = self$usage_data %>% filter(user == user_id)
      User$new(id = user_id, usage_data = user_data)
    },

    actions_map = function(flavor = "leaflet") {
      if (flavor == "leaflet") {
        plot_usage_actions_leaflet(self$usage_data)
      } else if (flavor == "mapview") {
        plot_usage_actions_mapview(self$usage_data)
      } else {
        stop("Invalid flavor!")
      }
    },

    first_actions_map = function() {
      first_actions = self$usage_data %>% group_by(user) %>% top_n(-1, datetime)
      mapview(first_actions, zcol = "action", legend = TRUE)
    }
  )
)