R/readthedown.R

In rmdformats: HTML Output Formats and Templates for 'rmarkdown' Documents

#' Convert to an HTML document
#'
#' Format for converting from R Markdown to an HTML document.
#'
#' @details
#' CSS adapted from the readtheorg theme of the org-html-themes project :
#' \url{https://github.com/fniessen/org-html-themes}, which is itself inspired by
#' the Read the docs theme : \url{https://readthedocs.org/}.
#'
#' @param fig_width Default width (in inches) for figures
#' @param fig_height Default width (in inches) for figures
#' @param fig_caption \code{TRUE} to render figures with captions
#' @param highlight Syntax highlighting style. Supported styles include
#'   "default", "tango", "pygments", "kate", "monochrome", "espresso",
#'   "zenburn", "haddock", and "textmate". Pass \code{NULL} to prevent syntax
#'   highlighting.
#' @param lightbox if TRUE, add lightbox effect to content images
#' @param thumbnails if TRUE display content images as thumbnails
#' @param gallery if TRUE and lightbox is TRUE, add a gallery navigation between images in lightbox display
#' @param pandoc_args arguments passed to the pandoc_args argument of rmarkdown \code{\link[rmarkdown]{html_document}}
#' @param md_extensions arguments passed to the md_extensions argument of rmarkdown \code{\link[rmarkdown]{html_document}}
#' @param toc_depth adjust table of contents depth
#' @param embed_fonts if TRUE, use local files for fonts used in the template. This leads to bigger files but ensures that these fonts are available. If FALSE they are downloaded from Google Web Fonts.
#' @param use_bookdown if TRUE, uses \code{\link[bookdown]{html_document2}} instead of \code{\link[rmarkdown]{html_document}}, thus providing numbered sections and cross references
#' @param mathjax set to NULL to disable Mathjax insertion
#' @param ... Additional function arguments passed to R Markdown \code{\link[rmarkdown]{html_document}}
#' @return R Markdown output format to pass to \code{\link[rmarkdown]{render}}
#' @import rmarkdown
#' @import bookdown
#' @importFrom htmltools htmlDependency
#' @export


readthedown <- function(fig_width = 8,
                       fig_height = 5,
                       fig_caption = TRUE,
                       highlight = "kate",
                       lightbox = FALSE,
                       thumbnails = FALSE,
                       gallery = FALSE,
                       toc_depth = 2,
                       embed_fonts = TRUE,
                       use_bookdown = FALSE,
                       pandoc_args = NULL,
                       md_extensions = NULL,
                       mathjax = "rmdformats",
                       ...) {

    html_template(
        template_name = "readthedown",
        template_path = "templates/template.html",
        template_dependencies = list(
            html_dependency_readthedown(embed_fonts)
        ),
        pandoc_args = pandoc_args,
        fig_width = fig_width,
        fig_height = fig_height,
        fig_caption = fig_caption,
        highlight = highlight,
        lightbox = lightbox,
        thumbnails = thumbnails,
        gallery = gallery,
        toc = TRUE,
        toc_depth = toc_depth,
        use_bookdown = use_bookdown,
        md_extensions = md_extensions,
        mathjax = mathjax,
        ...
    )

}

# readthedown js and css
html_dependency_readthedown <- function(embed_fonts = TRUE) {
  stylesheets <- "readthedown.css"
  if (embed_fonts) {
    stylesheets <- c(stylesheets, "readthedown_fonts_embed.css")
  } else {
    stylesheets <- c(stylesheets, "readthedown_fonts_download.css")
  }
  htmltools::htmlDependency(name = "readthedown",
                 version = "0.1",
                 src = system.file("templates/readthedown", package = "rmdformats"),
                 script = "readthedown.js",
                 stylesheet = stylesheets)
}