rshiny2.R

library(shiny)
library(readr)
library(raster)
library(DT)

# Define the UI
ui <- fluidPage(
  titlePanel("Crop and Country Selection"),
  sidebarLayout(
    sidebarPanel(
      selectInput("crop", "Select Crop:", choices = c("WHEA", "RICE", "MAIZ", "BARL", "PMIL", "SMIL")),
      selectInput("country", "Select Country:", choices = c("NGA", "CMR", "TZA", "COD", "AGO", "COG")),
      selectInput("agricultural_output", "Select Output Type:", choices = c("PRODUCTIVITY", "YIELD", "HARV_AREA", "PHYS_AREA", "VAL_PROD")),
      br(),
      downloadButton("download_csv", "Download CSV"),
      actionButton("generate_plot", "Generate Raster Plot"),
      plotOutput("raster_plot")
    ),
    mainPanel(
      textOutput("selected_options"),
      dataTableOutput("data_table")
    )
  )
)

# Define the server logic
server <- function(input, output) {
  
  # Display selected options
  output$selected_options <- renderText({
    paste("Selected Crop:", input$crop, "\n",
          "Selected Country:", input$country, "\n",
          "Selected Output Type:", input$agricultural_output)
  })
  
  # Create a reactive data frame
  data <- reactive({
    bd <- raster::getData('GADM', country = input$country, level = 1)
    ad <- length(bd)
    
    thetahat <- matrix(NA, ad, 1)
    names <- matrix(NA, ad, 2)
    
    x <- ifelse(input$agricultural_output == "PRODUCTIVITY", 
                paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_prod.geotiff/spam2010V2r0_global_P_", input$crop, "_A.tif"),
                ifelse(input$agricultural_output == "YIELD", 
                       paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_yield.geotiff/spam2010V2r0_global_Y_", input$crop, "_A.tif"), 
                ifelse(input$agricultural_output == "HARV_AREA", 
                       paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_harv_area.geotiff/spam2010V2r0_global_H_", input$crop, "_A.tif"), 
                ifelse(input$agricultural_output == "PHYS_AREA", 
                       paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_phys_area.geotiff/spam2010V2r0_global_A_", input$crop, "_A.tif"), ""))))
    
    raster1 <- raster(here::here(x))
    bd_raster <- crop(raster1, extent(bd))
    bd_raster2 <- mask(bd_raster, bd)
    
    d <- extract(x = bd_raster2, y = bd, fun = mean, na.rm = TRUE, sp = TRUE)
    thetahat[, 1] <- d@data[, 11] #was 13 before
    names[, 1] <- d@data[, 2]
    names[, 2] <- d@data[, 4]
    mat <- cbind(names, thetahat)
    
    data <- as.data.frame(mat)
    data
  })
  
  # Render the data table
  output$data_table <- renderDataTable({
    data()
  })
  
  # Render the raster plot
  output$raster_plot <- renderPlot({
    bd <- raster::getData('GADM', country = input$country, level = 1)
    
    x <- ifelse(input$agricultural_output == "PRODUCTIVITY", 
                paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_prod.geotiff/spam2010V2r0_global_P_", input$crop, "_A.tif"),
                ifelse(input$agricultural_output == "YIELD", 
                paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_yield.geotiff/spam2010V2r0_global_Y_", input$crop, "_A.tif"), 
                ifelse(input$agricultural_output == "HARV_AREA", 
                paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_harv_area.geotiff/spam2010V2r0_global_H_", input$crop, "_A.tif"), 
                ifelse(input$agricultural_output == "PHYS_AREA", 
                paste0("C:/Users/syedm/Desktop/soil/spam2010v2r0_global_phys_area.geotiff/spam2010V2r0_global_A_", input$crop, "_A.tif"), ""))))
    
    raster1 <- raster(here::here(x))
    bd_raster <- crop(raster1, extent(bd))
    bd_raster2 <- mask(bd_raster, bd)
    
    
    if (input$generate_plot > 0) {
      plot(bd)
      plot(bd_raster2, add = TRUE)
    }
  })
  
  # Download the data as a CSV file
  output$download_csv <- downloadHandler(
    filename = function() {
      paste("crop_country_data", Sys.Date(), ".csv", sep = "")
    },
    content = function(file) {
      write_csv(data(), file)
    }
  )
}

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