############################################
##  Missing Value Analysis - UI
############################################
## 1. 标签
missing_plots <- c("heatmap", "barplot")
names(missing_plots) <- c(
  i18n$t("Missing Heatmap"),
  i18n$t("Missing Barplot")
)

## 2. 函数形参
missing_args <- as.list(formals(missing))
missing_args <- missing_args[names(missing_args) %in% c("dataset", "vars", "data_filter")]

## 3. 输入收集
missing_inputs <- reactive({
  req(input$dataset)
  inputs <- list(
    dataset = input$dataset,
    vars = input$missing_vars,  # 用户选择的变量
    data_filter = if (input$show_filter) input$data_filter else "",
    envir = r_data
  )
  # 校验参数完整性
  for (arg in names(missing_args)) {
    if (is.null(inputs[[arg]]) || length(inputs[[arg]]) == 0) {
      inputs[[arg]] <- missing_args[[arg]]
    }
  }
  inputs
})

## 4. 变量选择UI
output$ui_missing_vars <- renderUI({
  req(input$dataset)
  current_data <- get_data(input$dataset, envir = r_data)
  all_vars <- colnames(current_data)
  
  if (length(all_vars) == 0) {
    return(div(class = "alert alert-warning", i18n$t("No variables in dataset. Please select another dataset.")))
  }
  
  # 显示变量类型（数值型/分类型）
  var_types <- sapply(current_data[, all_vars, drop = FALSE], function(col) class(col)[1])
  choices <- setNames(nm = paste0(all_vars, " {", var_types, "}"), object = all_vars)
  
  selectizeInput(
    inputId = "missing_vars",
    label = i18n$t("Select variables to analyze:"),
    choices = choices,
    selected = state_multiple("missing_vars", character(0)),
    multiple = TRUE,
    options = list(placeholder = i18n$t("Select one or more variables"), plugins = list("remove_button", "drag_drop"))
  )
})

## 5. 主UI（Summary + Plot标签页）
output$ui_missing <- renderUI({
  req(input$dataset)
  tagList(
    wellPanel(
      # Summary标签页：变量选择 + 统计结果
      conditionalPanel(
        condition = "input.tabs_missing == 'Summary'",
        uiOutput("ui_missing_vars")
      ),
      # Plot标签页：可视化类型选择
      conditionalPanel(
        condition = "input.tabs_missing == 'Plot'",
        selectizeInput(
          inputId = "missing_plots",
          label = i18n$t("Select plots:"),
          choices = missing_plots,
          selected = state_multiple("missing_plots", missing_plots, "barplot"),  # 默认选中条形图
          multiple = TRUE,
          options = list(placeholder = i18n$t("Select plot types"), plugins = list("remove_button", "drag_drop"))
        )
      )
    ),
    # 帮助与报告（和离群值分析保持一致）
    help_and_report(
      modal_title = i18n$t("Missing Value Analysis"),
      fun_name = "missing",
      help_file = inclMD(file.path(getOption("radiant.path.basics"), "app/tools/help/missing.md"))
    )
  )
})

## 6. 图表尺寸计算
missing_plot_dims <- reactive({
  req(.missing())
  plot_count <- length(input$missing_plots)
  var_count <- length(.missing()$vars)
  
  # 基础高度
  base_height_px <- if ("heatmap" %in% input$missing_plots) {
    min(500 + (nrow(.missing()$raw_data) * 0.5), 1200)  # 样本越多，热图越高
  } else {
    400
  }
  total_height_px <- base_height_px * plot_count
  
  # 限制最大/最小高度
  total_height_px <- min(total_height_px, 2000)
  total_height_px <- max(total_height_px, 500)
  
  list(
    width = 800,
    height = total_height_px
  )
})
missing_plot_width <- function() missing_plot_dims()$width
missing_plot_height <- function() missing_plot_dims()$height

## 7. 输出面板
output$missing <- renderUI({
  # 注册输出组件
  register_print_output("summary_missing", ".summary_missing")
  register_plot_output("plot_missing", ".plot_missing",
                       height_fun = "missing_plot_height")
  
  # 标签页布局（Summary + Plot）
  missing_panels <- tabsetPanel(
    id = "tabs_missing",
    tabPanel(
      title = i18n$t("Summary"),
      value = "Summary",
      verbatimTextOutput("summary_missing", placeholder = TRUE)
    ),
    tabPanel(
      title = i18n$t("Plot"),
      value = "Plot",
      download_link("dlp_missing"),  # 下载按钮
      plotOutput("plot_missing", height = "100%"),
      style = "margin-top: 10px;"
    )
  )
  
  # 集成到Data Quality菜单下
  stat_tab_panel(
    menu = i18n$t("Basics > Data Quality"),
    tool = i18n$t("Missing Value Analysis"),
    tool_ui = "ui_missing",
    output_panels = missing_panels
  )
})

## 8. 可用性检验
missing_available <- reactive({
  req(input$dataset)
  current_data <- get_data(input$dataset, envir = r_data)
  
  # 校验是否选择变量：未选则返回提示，阻止后续计算
  if (not_available(input$missing_vars)) {
    return(i18n$t("Please select at least one variable to analyze."))
  }
  
  # 校验变量是否存在
  invalid_vars <- input$missing_vars[!input$missing_vars %in% colnames(current_data)]
  if (length(invalid_vars) > 0) {
    return(i18n$t(paste("Invalid variables: ", paste(invalid_vars, collapse = ", "), ". Please reselect.", sep = "")))
  }
  
  "available"
})

## 9. 计算核心
.missing <- reactive({
  req(missing_available() == "available")
  do.call(missing, missing_inputs())
})

## 10. Summary输出
.summary_missing <- reactive({
  req(missing_available() == "available")
  summary(.missing())
})

## 11. Plot输出
.plot_missing <- reactive({
  req(missing_available() == "available")
  validate(need(input$missing_plots, i18n$t("Please select at least one plot type first.")))
  withProgress(message = i18n$t("Generating missing value plots..."), value = 0.5, {
    p <- plot(.missing(), plots = input$missing_plots, shiny = TRUE)
    setProgress(value = 1)
  })
  p
})

## 12. 下载功能
download_handler(
  id = "dlp_missing",
  fun = function(file) {
    plot_obj <- .plot_missing()
    width_in <- missing_plot_width() / 96
    height_in <- missing_plot_height() / 96
    
    ggsave(
      filename = file,
      plot = plot_obj,
      width = width_in,
      height = height_in,
      device = "png",
      dpi = 300,
      limitsize = FALSE,
      bg = "white"
    )
  },
  fn = function() paste0(input$dataset, "_missing_value_analysis"),
  type = "png",
  caption = i18n$t("Save missing value plots")
)

## 13. 报告生成
missing_report <- function() {
  req(missing_available() == "available")
  figs <- length(input$missing_plots) > 0
  update_report(
    inp_main = clean_args(missing_inputs(), missing_args),
    fun_name = "missing",
    inp_out = if (figs) list("", list(plots = input$missing_plots)) else list(""),
    outputs = if (figs) c("summary", "plot") else "summary",
    figs = figs,
    fig.width = missing_plot_width(),
    fig.height = missing_plot_height()
  )
}

## 14. 截图功能
observeEvent(input$missing_report, {
  r_info[["latest_screenshot"]] <- NULL
  missing_report()
})
observeEvent(input$missing_screenshot, {
  r_info[["latest_screenshot"]] <- NULL
  radiant_screenshot_modal("modal_missing_screenshot")
})
observeEvent(input$modal_missing_screenshot, {
  missing_report()
  removeModal()
})