#' barplot UI Function
#'
#' @description A shiny Module.
#'
#' @param id,input,output,session Internal parameters for {shiny}.
#'
#' @noRd 
#'
#' @importFrom shiny NS tagList
#' @importFrom plotly plotlyOutput renderPlotly ggplotly
#' @importFrom ggplot2 ggplot aes geom_col geom_text labs theme_classic scale_y_continuous theme position_stack
#' @importFrom scales unit_format
mod_barplot_ui <- function(id){
  ns <- NS(id)
  tagList(
    shinycssloaders::withSpinner(
      type = 5,
      hide.ui=F,
    plotly::plotlyOutput(ns("barplot"))
    )
  )
}

#' barplot Server Functions
#'
#' @noRd 
mod_barplot_server <- function(id, dat, ttl, cptn="Source: Download from SAP", ny=3000000){
  moduleServer( id, function(input, output, session){
    ns <- session$ns
    output$barplot<- plotly::renderPlotly({
      validate(
        need(nrow(dat)>0, 'Wait. Wrong button. There is nothing here. CLick something else.')
      )
      
      pl<-ggplot(dat, aes(x=name, y=amount, label=paste0(round(amount/1000000,1)," M")))+
        geom_col(fill="blue")+
        geom_text(col="black", nudge_y = ny)+
        scale_y_continuous(labels = unit_format(unit = "M", scale = 1e-6))+
        labs(title=ttl,
             subtitle = "",
             y="amount",
             x="",
             caption=cptn)+
        theme_classic()
      ggplotly(pl)
    })
    
  })
}

## To be copied in the UI
# mod_barplot_ui("barplot_ui_1")

## To be copied in the server
# mod_barplot_server("barplot_ui_1")