library(shiny)
    library(ggplot2)
    library(tidyr)
    library(dplyr)
    library(rlang)
    library(plotly)
    packageVersion('plotly')
    library(lubridate)
    library(base)
    library(leaflet)
    library(leaflet.extras)
    library(rdrop2)
    library(httr)
    library(rsconnect)

    token <- drop_auth()
    saveRDS(token, "droptoken.rds")



ui <- fluidPage(

  tags$style(type="text/css",
             ".recalculating {opacity: 1.0;}"
  ),

  leafletOutput(outputId = "mainmap", height = 600)

)

server <- function(input, output, session){

  rsconnect::setAccountInfo(name='xxxxx',
                            token='xxxxxxx',
                            secret='xxxxxxxxx')

  drop_auth(key = "xxxxxx", secret = "xxxxxxx", rdstoken = "droptoken.rds")


  bw <- reactive({
    load_data_dropbox()
  })


  load_data_dropbox <- function() {

    invalidateLater(600000, session)
    bw <-  drop_read_csv("ShipData_NMEA.csv", dtoken=token)

  }


  # Plot the latest position of the vessel
  ShipNames_DF <- reactive({


    bwtemp <- NULL
    ShipNames <- unique(as.character(bw()$ShipName))
    ShipNames_DF <- data.frame(ShipNames)
    ShipNames_DF$MaxDate <- as.POSIXct("1900-01-01 00:00:00")
    ShipNames_DF$Lat <- NA
    ShipNames_DF$Lon <- NA
    ShipNames_DF$GPSSpeed <- NA
    ShipNames_DF$WindSpeedTrue <- NA
    ShipNames_DF$WindDirectionTrue <- NA



    for (i in 1:nrow(ShipNames_DF)){
      bwtemp<- NULL
      bwtemp <- bw() %>%
        filter(ShipName == ShipNames_DF$ShipNames[i])

      bwtemp$DateTime <- as.POSIXct(bwtemp$DateTime)

      bwtemp <- bwtemp[1,]

      ShipNames_DF$MaxDate[i] <- bwtemp$DateTime[1]
      ShipNames_DF$Lat[i] <- bwtemp$Lat[1]
      ShipNames_DF$Lon[i] <- bwtemp$Lon[1]
      ShipNames_DF$GPSSpeed[i] <- bwtemp$GPSSpeed[1]
      ShipNames_DF$WindSpeedTrue[i] <- bwtemp$WindSpeedTrue[1]
      ShipNames_DF$WindDirectionTrue[i] <- bwtemp$WindDirectionTrue[1]
    }
    bwtemp <- NULL
    ShipNames_DF <- as.data.frame(ShipNames_DF)

    return(ShipNames_DF)

  })



  # To plot the last 24 hours sailing position to give indication on the heading
  Direction_DF <- reactive({

    bwtemp <- NULL

    ShipNames_DFin <- ShipNames_DF()


    Direction_DF <- NA
    for (i in 1:nrow(ShipNames_DFin)){
      bwtemp<- NULL
      bwtemp <- bw() %>%
        filter(ShipName == ShipNames_DFin$ShipNames[i])

      bwtemp <- bwtemp[1:144,]

      Direction_DF <- rbind(Direction_DF, bwtemp)

    }
    bwtemp <- NULL
    Direction_DF <- as.data.frame(Direction_DF)

    return(Direction_DF)

    list(df1)

  })



  output$mainmap <- renderLeaflet({


    ShipNames_DFin <- ShipNames_DF()

    Direction_DFin <- Direction_DF()


    leaflet(data) %>%
      setView(lng = 120, lat = -40, zoom = 2.8)  %>%
      addTiles() %>%
      addTerminator(group = "Day or Night") %>%
      addCircleMarkers(data = ShipNames_DFin, lat = ~Lat, lng = ~Lon, label = ~MaxDate, weight = 1,
                       labelOptions = labelOptions(noHide = T,
                                                   textOnly = TRUE,
                                                   direction = "bottom",
                                                   style = list("color" = "black",
                                                                "font-size" = "12px"))) %>%
      addPolylines(data = subset(Direction_DFin, ShipName == "Black Pearl"), lat = ~Lat, lng = ~Lon, color = "black", weight = 1.4, dashArray = '5, 5',  group = "48hr sailed") %>%
      addLayersControl(
        overlayGroups = c("48hr sailed", "Day or Night"),
        options = layersControlOptions(collapsed = FALSE)
      )

  })

}

shinyApp(ui=ui, server=server)