#
# This is a Shiny web application. You can run the application by clicking
# the 'Run App' button above.
#
# Find out more about building applications with Shiny here:
#
#    http://shiny.rstudio.com/
#

## Instructions:
##  Add a selection option using selectInput in the sidebar that let's you choose between a normal and uniform (or other) distributions

library(shiny)
library(ggplot2)
library(gridExtra)
vals <- rnorm(5000)

# Define UI for application that draws a histogram
ui <- fluidPage(
    
    # Application title
    titlePanel("Random distribution generation"),
    
    # Sidebar with a slider input for number of bins 
    sidebarLayout(
        sidebarPanel(
            sliderInput("bins",
                        "Number of bins:",
                        min = 1,
                        max = 50,
                        value = 30),
            radioButtons("type","Select the distribution",choices=c("uniform","normal")),
            tags$a("Link to wikipedia",href="http://en.wikipedia.org"),
            tags$p("this is a paragraph of text"),
            tags$hr(),
            tags$img(src="https://upload.wikimedia.org/wikipedia/en/c/c9/Michigan_Technological_University_logo.svg"),
            tags$img(src="saling.png",width=150) ## notice this is in www\ directory
            
        ),
        
        # Show a plot of the generated distribution
        mainPanel(
            h1("Histogram and normal q-q plot"),
            plotOutput("distPlot")
        )
    )
)

# Define server logic required to draw a histogram
server <- function(input, output) {
    
    output$distPlot <- renderPlot({

       if(input$type=="uniform")
        {
          x    <- runif(1000)
        } else if(input$type=="normal")
        {
          x    <-  rnorm(1000)
        } else{
           x <- 1:1000
        }
        
        # draw the histogram with the specified number of bins
        a <- as.data.frame(x) |> ggplot(aes(x=x)) +geom_histogram(bins=input$bins,fill="orange2",color="black") + theme_bw()
        b <- as.data.frame(x) |> ggplot(aes(sample=x)) + geom_qq() + theme_bw()
        grid.arrange(a,b,ncol=2)
        
      })
      
}

# Run the application 
shinyApp(ui = ui, server = server)