#' one_objective_focus UI Function
#'
#' @description A shiny Module.
#'
#' @param id,input,output,session Internal parameters for {shiny}.
#'
#' @noRd
#'
#' @importFrom shiny NS tagList
#' @importFrom rvgest objectives
mod_one_objective_focus_ui <- function(id){
  ns <- NS(id)
  rulesets <- seq(length(rvgest::rulesets$rules))
  names(rulesets) <- paste0(rulesets, ". ", rvgest::rulesets$rules)
  stations <- unique(rvgest::objectives$station)
  names(stations) <- stations
  levels <- unique(rvgest::objectives$level)
  names(levels) <- levels
  tagList(
    selectInput(
      ns("ruleset"),
      "Rule set",
      rulesets,
      selected = NULL,
      multiple = FALSE,
      selectize = TRUE,
      width = NULL,
      size = NULL
    ),
    selectInput(
      ns("station"),
      "Station",
      stations,
      selected = NULL,
      multiple = FALSE,
      selectize = TRUE,
      width = NULL,
      size = NULL
    ),
    selectInput(
      ns("level"),
      "Flow threshold",
      levels,
      selected = NULL,
      multiple = FALSE,
      selectize = TRUE,
      width = NULL,
      size = NULL
    ),
    uiOutput(ns("plots"))
  )
}

#' one_objective_focus Server Functions
#'
#' @noRd
mod_one_objective_focus_server <- function(id, con){
  moduleServer( id, function(input, output, session){
    ns <- session$ns
    observe({
      objective <- rvgest::objectives[rvgest::objectives$station == input$station & rvgest::objectives$level == input$level,]
      indexMonths <- c(1,31,28,31,30,31,30,31,31,30,31,30)
      labels <- unlist(strsplit("JFMAMJJASOND", NULL))
      iBreaks <- sapply(seq.int(12), function(i) sum(indexMonths[1:i]))
      lapply(objective$lakes[[1]]$name, function(lake) {
        dfDiscretProbs <- calcRiskHeatMap(con, input$ruleset, objective$station, objective$level, lake)
        if(!is.null(dfDiscretProbs)) {
          breaks <- sapply(iBreaks, function(x) levels(dfDiscretProbs$day)[x])
          objCurve <- data.frame(day = objectiveStorageCurves$day, V = round(objectiveStorageCurves[[lake]]))
          objCurve <- objCurve[seq.int(1, 365,3),]
          p <- ggplot(dfDiscretProbs, aes(x = day, y = V)) +
            geom_tile(aes(fill = prob)) +
            scale_fill_continuous(low = "green", high = "red", name = "Failure probability") +
            geom_point(data = objCurve, color = "black", size = 1, shape = 21, fill = "grey") +
            ggtitle(paste("Lake", lake)) +
            scale_x_discrete("Calendar days", breaks = breaks, labels = labels) +
            scale_y_continuous(name="Reservoir storage (hm3)")
          output[[paste("plot", lake, sep = "_")]] <- renderPlot({p},width = 640, height = 280)
        }
      })

    })

    output$plots <- renderUI({
      objective <- rvgest::objectives[rvgest::objectives$station == input$station & rvgest::objectives$level == input$level,]
      plot_output_list <- lapply(objective$lakes[[1]]$name, function(lake) {
        plotname <- paste("plot", lake, sep = "_")
        plotOutput(ns(plotname), height = '250px', inline=TRUE)
      })
      do.call(tagList, plot_output_list)
     })
  })
}

## To be copied in the UI
# mod_one_objective_focus_ui("one_objective_focus_ui_1")

## To be copied in the server
# mod_one_objective_focus_server("one_objective_focus_ui_1")