library(shiny)
library(bslib)
library(ggplot2)

# install.packages("palmerpenguins")
data(penguins, package = "palmerpenguins")

ui <- page_navbar(
  title = "Penguins dashboard",
  sidebar = selectInput(
    selected = "species",
    inputId = "color_by",
    label = "Color by",
    choices = c(
      "species",
      "island",
      "sex"
    )
  ),
  collapsible = nav_spacer(),
  nav_panel(
        "Bill Length", 
        card(
          full_screen = TRUE,
          card_header("Bill Length"),
          plotOutput("bill_length")
        )
      ),
  nav_panel(
        "Bill Depth", 
        card(
          full_screen = TRUE,
          card_header("Bill depth"),
          plotOutput("bill_depth")
        )
      ),
  nav_panel(
        "Body Mass", 
        card(
          full_screen = TRUE,
          card_header("Body Mass"),
          plotOutput("body_mass")
        )
      ),
  nav_item(tags$a("Posit", href = "https://posit.co"))
)

server <- function(input, output) {
  gg_plot <- reactive({
    ggplot(penguins) +
      geom_density(aes(fill = !!input$color_by), alpha = 0.2) +
      theme_bw(base_size = 16) +
      theme(axis.title = element_blank())
  })
  
  output$bill_length <- renderPlot(gg_plot() + aes(bill_length_mm))
  output$bill_depth <- renderPlot(gg_plot() + aes(bill_depth_mm))
  output$body_mass <- renderPlot(gg_plot() + aes(body_mass_g))
}

shinyApp(ui, server)