introduce decorators for tm_g_ci (#1265)

Part of insightsengineering/teal#1371

WIP

<details>
<summary> Example with decorator </summary>

```r
devtools::load_all("../teal")
devtools::load_all(".")
library(nestcolor)

data <- teal_data()
data <- within(data, {
  ADSL <- tmc_ex_adsl
  ADLB <- tmc_ex_adlb
})
join_keys(data) <- default_cdisc_join_keys[names(data)]

ADSL <- data[["ADSL"]]
ADLB <- data[["ADLB"]]

caption_decorator <- function(default_caption = "I am a good decorator", .var_to_replace = "plot") {
  teal_transform_module(
    label = "Caption",
    ui = function(id) shiny::textInput(shiny::NS(id, "footnote"), "Footnote", value = default_caption),
    server = make_teal_transform_server(
      substitute({
        .var_to_replace <- .var_to_replace + ggplot2::labs(caption = footnote)
      }, env = list(.var_to_replace = as.name(.var_to_replace)))
    )
  )
}



app <- init(
  data = data,
  modules = modules(
    tm_g_ci(
      label = "Confidence Interval Plot",
      x_var = data_extract_spec(
        dataname = "ADSL",
        select = select_spec(
          choices = c("ARMCD", "BMRKR2"),
          selected = c("ARMCD"),
          multiple = FALSE,
          fixed = FALSE
        )
      ),
      y_var = data_extract_spec(
        dataname = "ADLB",
        filter = list(
          filter_spec(
            vars = "PARAMCD",
            choices = levels(ADLB$PARAMCD),
            selected = levels(ADLB$PARAMCD)[1],
            multiple = FALSE,
            label = "Select lab:"
          ),
          filter_spec(
            vars = "AVISIT",
            choices = levels(ADLB$AVISIT),
            selected = levels(ADLB$AVISIT)[1],
            multiple = FALSE,
            label = "Select visit:"
          )
        ),
        select = select_spec(
          label = "Analyzed Value",
          choices = c("AVAL", "CHG"),
          selected = "AVAL",
          multiple = FALSE,
          fixed = FALSE
        )
      ),
      color = data_extract_spec(
        dataname = "ADSL",
        select = select_spec(
          label = "Color by variable",
          choices = c("SEX", "STRATA1", "STRATA2"),
          selected = c("STRATA1"),
          multiple = FALSE,
          fixed = FALSE
        )
      ),
      decorators = list(caption_decorator(.var_to_replace = "plot"))
    )
  )
)
shinyApp(app$ui, app$server)
```

</details>

---------

Co-authored-by: Marcin <[email protected]>
Co-authored-by: m7pr <[email protected]>

R/tm_g_ci.R

@@ -171,8 +171,7 @@ template_g_ci <- function(dataname,
 
   substitute(
     expr = {
-      gg <- graph_expr
-      print(gg)
+      plot <- graph_expr
     },
     env = list(graph_expr = pipe_expr(graph_list, pipe_str = "+"))
   )
@@ -189,6 +188,14 @@ template_g_ci <- function(dataname,
 #'
 #' @inherit module_arguments return seealso
 #'
+#' @section Decorating `tm_g_ci`:
+#'
+#' This module generates the following objects, which can be modified in place using decorators:
+#' - `plot` (`ggplot2`)
+#'
+#' For additional details and examples of decorators, refer to the vignette
+#' `vignette("decorate-modules-output", package = "teal")` or the [`teal_transform_module()`] documentation.
+#'
 #' @examplesShinylive
 #' library(teal.modules.clinical)
 #' interactive <- function() TRUE
@@ -275,7 +282,8 @@ tm_g_ci <- function(label,
                     plot_width = NULL,
                     pre_output = NULL,
                     post_output = NULL,
-                    ggplot2_args = teal.widgets::ggplot2_args()) {
+                    ggplot2_args = teal.widgets::ggplot2_args(),
+                    decorators = NULL) {
   message("Initializing tm_g_ci")
   checkmate::assert_string(label)
   stat <- match.arg(stat)
@@ -293,6 +301,8 @@ tm_g_ci <- function(label,
   checkmate::assert_class(pre_output, classes = "shiny.tag", null.ok = TRUE)
   checkmate::assert_class(post_output, classes = "shiny.tag", null.ok = TRUE)
   checkmate::assert_class(ggplot2_args, "ggplot2_args")
+  decorators <- normalize_decorators(decorators)
+  assert_decorators(decorators, null.ok = TRUE, "plot")
 
   args <- as.list(environment())
 
@@ -306,7 +316,8 @@ tm_g_ci <- function(label,
       label = label,
       plot_height = plot_height,
       plot_width = plot_width,
-      ggplot2_args = ggplot2_args
+      ggplot2_args = ggplot2_args,
+      decorators = decorators
     ),
     ui = ui_g_ci,
     ui_args = args,
@@ -355,7 +366,8 @@ ui_g_ci <- function(id, ...) {
         label = "Statistic to use",
         choices = c("mean", "median"),
         selected = args$stat
-      )
+      ),
+      ui_decorate_teal_data(ns("decorator"), decorators = select_decorators(args$decorators, "plot"))
     ),
     forms = tagList(
       teal.widgets::verbatim_popup_ui(ns("rcode"), "Show R code")
@@ -376,7 +388,8 @@ srv_g_ci <- function(id,
                      label,
                      plot_height,
                      plot_width,
-                     ggplot2_args) {
+                     ggplot2_args,
+                     decorators) {
   with_reporter <- !missing(reporter) && inherits(reporter, "Reporter")
   with_filter <- !missing(filter_panel_api) && inherits(filter_panel_api, "FilterPanelAPI")
   checkmate::assert_class(data, "reactive")
@@ -466,11 +479,18 @@ srv_g_ci <- function(id,
       teal.code::eval_code(anl_q(), list_calls)
     })
 
-    plot_r <- reactive(all_q()[["gg"]])
+    decorated_plot_q <- srv_decorate_teal_data(
+      id = "decorator",
+      data = all_q,
+      decorators = select_decorators(decorators, "plot"),
+      expr = print(plot)
+    )
+    # Outputs to render.
+    plot_r <- reactive(decorated_plot_q()[["plot"]])
 
     teal.widgets::verbatim_popup_srv(
       id = "rcode",
-      verbatim_content = reactive(teal.code::get_code(all_q())),
+      verbatim_content = reactive(teal.code::get_code(req(decorated_plot_q()))),
       title = label
     )
 
@@ -497,7 +517,7 @@ srv_g_ci <- function(id,
           card$append_text("Comment", "header3")
           card$append_text(comment)
         }
-        card$append_src(teal.code::get_code(all_q()))
+        card$append_src(teal.code::get_code(req(decorated_plot_q())))
         card
       }
       teal.reporter::simple_reporter_srv("simple_reporter", reporter = reporter, card_fun = card_fun)