use_custom_build

use_custom_build <- function(file) {
  stopifnot(file_exists(file))
  
  build_pane_active <- has_buildtype()
  bail_out <- check_buildtype()
  if (bail_out) {
    return(invisible(NULL))
  }
  
  file_chmod(file, "+x")
  
  write_buildtype()

  if (!build_pane_active) rstudio_tickle_build()

  invisible(NULL)
}

has_buildtype <- function() {
  any(stringr::str_detect(readLines(rproj_path()), "BuildType"))
}

rstudio_tickle_build <- function() {
  restart_rstudio <- ui_yeah("RStudio needs to restart to activate the \\
                             build pane. Restart now?")

  if (restart_rstudio) {
    rstudioapi::openProject(proj_get(), newSession = FALSE)
  }
}

write_buildtype <- function() {
  rproj_text <- readLines(rproj_path())
  remove <- stringr::str_detect(
    readLines(rproj_path()),
    "BuildType|PackageInstallArgs|PackageUseDevtools|CustomScriptPath",
    negate = TRUE
  )

  rproj_text <- c(
    rproj_text[remove],
    "", "BuildType: Custom", "CustomScriptPath: _make.R", ""
  )

  ui_done("Writing {ui_path(rproj_path())}")
  writeLines(
    rproj_text,
    rproj_path()
  )
}

check_buildtype <- function() {
  if (has_buildtype()) {
    change_it <- ui_yeah(
      "Detected an existing build binding in {ui_path(rproj_path())}. \\
    Override existing binding?"
    )

    if (!change_it) {
      ui_info("In RStudio, change your build settings in \\
              `Tools > Project Options > Build Tools`.")
      return(invisible(TRUE))
    }
  }

  invisible(FALSE)
}