R/mod_egfr_data.R

In CovalenceResearch/sloper-public: A Simple Calculator to Project Dialysis Costs Based on eGFR Slopes

#' UI function for eGFR data
#'
#' @description UI for module to capture baseline eGFR and eGFR at which
#'   dialysis is initiated.
#'
#' @param id,input,output,session Internal parameters for {shiny}.
#'
#' @noRd
#'
#' @importFrom shiny NS tagList
mod_egfr_data_ui <- function(id) {
  ns <- NS(id)
  tagList(
    splitLayout(
      numericInputEGFR(ns("base_egfr"),
        HTML(paste0("Baseline eGFR (mL/min/1.73m", tags$sup("2"), ")")),
        value = 90,
        width = "100%"
      ),
      numericInputEGFR(ns("dial_threshold"),
        HTML(paste0("Dialysis at eGFR (mL/min/1.73m", tags$sup("2"), ")")),
        value = 10,
        width = "100%"
      )
    )
  )
}

#' Server function for eGFR data
#'
#' @description Server for module to capture baseline eGFR and eGFR at which
#'   dialysis is initiated.
#' @noRd
mod_egfr_data_server <- function(id) {
  moduleServer(id, function(input, output, session) {
    ns <- session$ns

    iv <- shinyvalidate::InputValidator$new()
    iv$add_rule("base_egfr", shinyvalidate::sv_required())
    iv$add_rule("base_egfr", function(value) {
      if (value < 0) {
        "Must not be negative"
      }
    })

    iv$add_rule("dial_threshold", shinyvalidate::sv_required())
    iv$add_rule("dial_threshold", function(value) {
      if (value < 0) {
        "Must not be negative"
      }
    })
    iv$add_rule(
      "dial_threshold",
      function(value) {
        if (shinyvalidate::input_provided(input$base_egfr) &
          value > input$base_egfr) {
          "Must not be higher than base eGFR."
        }
      }
    )

    iv$enable()

    egfr_data <- reactive({
      req(iv$is_valid())

      reactiveValues(
        base_egfr = input$base_egfr,
        dial_threshold = input$dial_threshold
      )
    })
  })
}

## To be copied in the UI
# mod_egfr_data_ui("egfr_data_ui_1")

## To be copied in the server
# mod_egfr_data_server("egfr_data_ui_1")