R/g2r.R

In devOpifex/g2r: Interactive Grammar of Graphics

#' Initialise
#'
#' Initialise a chart.
#'
#' @param data A data.frame or tibble containing data to chart,
#' an object of class `igraph`, an object of class `ts`,
#' or as `crosstalk::sharedDataset`.
#' @param ... Aspects of the chart, see [asp()].
#' @param width,height Dimensions of the chart, accepts
#' any valid CSS unit e.g.: `100%`, numerics are treated
#' as pixels, e.g.: `400` = `400px`.
#' @param elementId Valid CSS id attribute.
#' @param digits Maximum number of digits after the comma to show
#' on the chart.
#' @param reorder Whether to internally reorder the data, namely
#' the `x` and `color`. The `x` axis must be reordered in a descending
#' order for most data type since G2.js plots data as-is. Moreover,
#' `color` order of all data.frames passed either to this function or
#' subsequent `fig_*` layers must be identical or the colors will
#' might match the legends on the plot. However, one may sometimes
#' not want the data to be reordered.
#'
#' @examples
#' g2(cars) %>%
#'   fig_point(asp(speed, dist))
#' @import htmlwidgets
#'
#' @export
g2 <- function(
  data = NULL,
  ...,
  width = NULL,
  height = NULL,
  elementId = NULL,
  digits = NULL,
  reorder = TRUE
) {
  UseMethod("g2")
}

#' @export
g2.default <- function(
  data = NULL,
  ...,
  width = NULL,
  height = NULL,
  elementId = NULL,
  digits = NULL,
  reorder = TRUE
) {
  asp <- get_asp(...)

  if (is_asp(data)) {
    asp <- data
    data <- NULL
  }

  x <- list(
    reorder = reorder,
    data = to_g2r(data),
    # dataset
    main_asp = asp,
    # main aspects
    views = list(),
    # views | figures
    scale = list(),
    # chart.scale
    cols = c() # keep track of columns for filter
  )

  as_widget(x, width, height, elementId, digits)
}

#' @export
#' @method g2 data.frame
g2.data.frame <- function(
  data = NULL,
  ...,
  width = NULL,
  height = NULL,
  elementId = NULL,
  digits = NULL,
  reorder = TRUE
) {
  asp <- get_asp(...)

  x <- list(
    reorder = reorder,
    data = to_g2r(data),
    # dataset
    main_asp = asp,
    # main aspects
    views = list(),
    # views | figures
    scale = list(),
    # chart.scale
    cols = c() # keep track of columns for filter
  )

  as_widget(x, width, height, elementId, digits)
}

#' @export
#' @method g2 igraph
g2.igraph <- function(
  data = NULL,
  ...,
  width = NULL,
  height = NULL,
  elementId = NULL,
  digits = NULL,
  reorder = TRUE
) {
  asp <- get_asp(...)

  x <- list(
    reorder = reorder,
    graph = data,
    data = to_g2r(data),
    # dataset
    main_asp = asp,
    # main aspects
    views = list(),
    # views | figures
    scale = list(),
    # chart.scale
    cols = c() # keep track of columns for filter
  )

  as_widget(x, width, height, elementId, digits)
}

#' @export
#' @method g2 SharedData
g2.SharedData <- function(
  data = NULL,
  ...,
  width = NULL,
  height = NULL,
  elementId = NULL,
  digits = NULL,
  reorder = TRUE
) {
  asp <- get_asp(...)

  key_col <- "CROSSTALK_KEYS"

  dataset <- data$origData()
  dataset[[key_col]] <- data$key()

  x <- list(
    reorder = reorder,
    crosstalk_group = data$groupName(),
    data = dataset,
    # dataset
    main_asp = asp,
    # main aspects
    views = list(),
    # views | figures
    scale = list(),
    # chart.scale
    cols = c(key_col) # keep track of columns for filter
  )

  as_widget(x, width, height, elementId, digits)
}

#' Shiny Bindings
#'
#' Output and render functions for using g2r within Shiny
#' applications and interactive Rmd documents.
#'
#' @param outputId output variable to read from
#' @param width,height Must be a valid CSS unit (like \code{'100\%'},
#'   \code{'400px'}, \code{'auto'}) or a number, which will be coerced to a
#'   string and have \code{'px'} appended.
#' @param expr An expression that generates a g2r
#' @param env The environment in which to evaluate \code{expr}.
#' @param quoted Is \code{expr} a quoted expression (with \code{quote()})? This
#'   is useful if you want to save an expression in a variable.
#'
#' @name g2r-shiny
#'
#' @export
g2Output <- function(outputId, width = "100%", height = "400px") {
  shinyWidgetOutput(outputId, "g2r", width, height, package = "g2r")
}

#' @rdname g2r-shiny
#' @export
renderG2 <- function(expr, env = parent.frame(), quoted = FALSE) {
  if (!quoted) {
    expr <- substitute(expr)
  } # force quoted
  shinyRenderWidget(expr, g2Output, env, quoted = TRUE)
}