helpers-generic.R

# Inspired by Thomas Mock's tidytuesdaymeta package.

next_tuesday <- function() {
  todays_date <- lubridate::today(tzone = "America/New_York")
  # Tuesday is 3. How many days are we before Tuesday?
  diff_tuesday <- 3 - lubridate::wday(
    todays_date,
    week_start = 7 # Code explicitly to avoid strangeness.
  )
  if (diff_tuesday < 0) {
    diff_tuesday <- diff_tuesday + 7
  }
  return(todays_date + diff_tuesday)
}

next_week_num <- function() {
  week_date <- next_tuesday()
  year <- lubridate::year(week_date)
  jan_1st <- paste0(year, "0101")
  jan_1st <- lubridate::ymd(jan_1st)
  week_num <- as.numeric((week_date - jan_1st))/7 + 1
  return(floor(week_num))
}

next_year <- function() {
  week_date <- next_tuesday()
  year <- lubridate::year(week_date)
  return(year)
}

read_post_vars <- function() {
  post_vars <- read_yaml_or_null(next_file("meta.yaml")) %||%
    read_yaml_or_null(next_file("meta.yml")) %||%
    read_yaml_or_null(next_file("post_vars.yaml")) %||%
    read_yaml_or_null(next_file("post_vars.yml")) %||%
    read_yaml_or_null(next_file("post_vars.json"))
  if (length(post_vars)) {
    return(post_vars)
  }
  cli::cli_abort("Failed to load post_vars.")
}

read_yaml_or_null <- function(url) {
  tryCatch(
    yaml::read_yaml(url),
    error = function(e) {
      return(NULL)
    },
    warning = function(e) {
      return(NULL)
    }
  )
}

next_dir <- function() {
  return(
    file.path(
      "https://raw.githubusercontent.com/rfordatascience/tidytuesday/main/data",
      next_year(),
      next_tuesday()
    )
  )
}

next_file <- function(filename) {
  return(
    file.path(
      next_dir(),
      filename
    )
  )
}