Task 3

global.R

library(dplyr)
library(shiny)
library(nycflights13)
library(ggplot2)
library(ggthemes)

options(scipen = 999)

flights <- flights
airlines <- airlines

# łączenie dwóch dataframe'ów
modFlights <- flights %>% 
  inner_join(airlines, by = 'carrier')

# wybór siedmu linii lotniczych
chosenCarrier <- modFlights %>% count(name) %>% 
  arrange(desc(n)) %>% 
  head(7)

# filtrowanie danych 
modFlights <- modFlights %>% 
  filter(!is.na(dep_delay), name %in% chosenCarrier$name)

server.R

shinyServer(function(input, output, session) {
  
  output$ddelay_plot <- renderPlot({
    
    aggDelayFlights <- modFlights %>% 
      group_by(hour) %>% 
      summarise(delayed_flight_perc = sum(dep_delay > 0) / n())
    
    ggplot(aggDelayFlights, aes(hour, delayed_flight_perc)) +
      geom_col(position = 'dodge') +
      theme_hc(base_size = 18) +
      scale_fill_hc() +
      xlab("Departure hour") +
      ylab("Percentage of delayed flights") +
      scale_y_continuous(labels = scales::percent) +
      scale_x_continuous(limits = c(0,24), breaks = seq(0, 24, 2)) +
      guides(fill=guide_legend(title=""))
    
  })
  
  output$table <- renderTable({
    modFlights %>% 
      group_by(hour) %>% 
      summarise(delayed_flight_perc = sum(dep_delay > 0) / n()) %>% 
      mutate(
        delayed_flight_perc = scales::percent(delayed_flight_perc)
      )
  })
})

ui.R

fluidPage(
  titlePanel(title = "Introduction to Shiny"),
  sidebarPanel(
    selectInput("carrierName", 
                label = "Select carrier:",
                choices = sort(chosenCarrier$name),
                selected = sort(chosenCarrier$name)[1],
                multiple = T),
    sliderInput('delayFlightRange',
                label = "Choose minutes range of delay flights:",
                min = 0, max = 1000, value = c(0, 1000), step = 5),
    numericInput("distance_val", label = "Flight distance longer than (miles):", value = 500)
  ),
  mainPanel(
    tabsetPanel(
      tabPanel("Delay over day",
               plotOutput('ddelay_plot')
      ),
      tabPanel("Explore data",
               tableOutput("table")
      )  
    )
  )
)