# Alpha Module Server function


#Helper Function in order to load Rda without names

loadRData <- function(fileName){
    #loads an RData file, and returns it
    load(fileName)
    get(ls()[ls() != "fileName"])
}


alphaServer <- function(input, output, session) {
    # TODO: Put Server logic here

    userData<-reactiveValues()

    observeEvent(input$file1, {
        userData$df <- loadRData(input$file1$datapath)

    })

    output$phylo <- renderPlot({
        title <- "Alpha Diversity Metrics"
        selected_theme<-switch(input$plotTheme,
                               "Grey theme" = theme_gray() ,
                               "Black & White theme" =theme_bw(),
                               "Classic theme" = theme_classic()

        )

        theme_set(selected_theme)
          have_input<-input$file1 #Check if user input exists

         if(!is.null(have_input)){
             validate(need(class(userData$df)!="phyloseq","Only phyloseq files are currently supported"))
             plot_richness(userData$df, measures = c("Observed", input$groupSelection))

         }

        else if (input$dataSelection == "global") {
            data("GlobalPatterns")
            plot_richness(GlobalPatterns, measures = c("Observed", input$groupSelection))
        } else if (input$dataSelection == "esophagus") {
            data("esophagus")
            plot_richness(esophagus, measures = c("Observed", input$groupSelection))
        }
    })
}