shiny-ggplot2

library(shiny)

summer <- read.csv("summer.csv")
winter <- read.csv("winter.csv")
games <- rbind.data.frame(summer, winter)
games <- games[games$Country != "", ]

# Define UI for application that draws a histogram
ui <- fluidPage(

    # Application title
    titlePanel("Olympic Games"),

    # Sidebar with a slider input for number of bins 
    sidebarLayout(
        sidebarPanel(
            selectInput("season",
                        "Season",
                        choices = c("Summer", "Winter")),
            uiOutput("special"),
            selectInput("country", 
                        "Country",
                        choices = sort(unique(games$Country)), 
                        selected = "FRA"),
            radioButtons("graph", "Graph", 
                         choices = c("Area plot", "Line plot"),
                         selected = "Area plot")
        ),

        # Show a plot of the generated distribution
        mainPanel(
           fluidRow(DT::dataTableOutput("table")),
           fluidRow(column(6, plotOutput("distPlot")),
           column(6, plotOutput("distPlot2")))
        )
    )
)

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

    output$special <- renderUI({
        switch(input$season,
               "Winter" = selectInput("year", "Year", 
                                      choices = unique(winter$Year),
                                      selected = "2012"),
               "Summer" = selectInput("year", "Year", 
                                      choices = unique(summer$Year),
                                      selected = "2012"))
    })
    
    output$distPlot <- renderPlot({
        
        if (input$season == 'Winter'){
            games <- winter
        }else{
            games <- summer
        }
        
        dat <- games %>% filter(Year == req(input$year), 
                                Country == req(input$country)) 
        
        ggplot(data = dat, aes(x = Medal, fill = Medal)) + geom_bar() + 
            scale_fill_manual(values = c("Bronze" = "#cd7f32", 
                                        "Gold" = "gold", 
                                        "Silver" = "lightgray")) +
            theme_bw()
    })
    
    output$distPlot2 <- renderPlot({
        if (input$season == 'Winter'){
            games <- winter
        }else{
            games <- summer
        }
        dat <- games %>% filter(Country == req(input$country),
                                Year >= as.numeric(input$year) - 15,
                                Year <= as.numeric(input$year) + 15)
        counts <- dat %>% group_by(Year, Medal) %>% tally
        
        if (input$graph == 'Area plot'){
            ggplot(data = counts, 
                   aes(x = Year, y = n, group = Medal, fill = Medal)) + 
                geom_area() + 
                scale_fill_manual(values = c("Bronze" = "#cd7f32", 
                                             "Gold" = "gold", 
                                             "Silver" = "lightgray")) +
                theme_bw() + 
                scale_x_continuous(breaks = sort(counts$Year))
        }else{
            ggplot(data = counts, aes(x = Year, y = n, group = Medal, color = Medal)) + geom_line(lwd = 2) + 
                scale_color_manual(values = c("Bronze" = "#cd7f32", 
                                              "Gold" = "gold", 
                                              "Silver" = "lightgray")) + 
                theme_bw() + scale_x_continuous(breaks = sort(counts$Year))
        }
        })
    
    output$table <- DT::renderDataTable(DT::datatable({
        if (input$season == 'Winter'){
            games <- winter
        }else{
            games <- summer
        }
        dat <- games %>% filter(Year == req(input$year), 
                                Country == req(input$country)) %>%
            select(-c(Year, Country))
        dat
    }))
}


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