Implement multi-part exercises

src/app/learnocaml_common.ml

@@ -941,6 +941,42 @@ let set_nickname_div () =
   | nickname -> Manip.setInnerText nickname_div nickname
   | exception Not_found -> ()
 
+(* setup for the prelude in the description page (in description_main.ml) *)
+let setup_tab_text_prelude_pane prelude =
+  if prelude = "" then () else
+  let iframe_pane = find_component "learnocaml-exo-tab-text-iframe" in
+  let prelude_pane = find_component "learnocaml-exo-tab-text-prelude" in
+  let open Tyxml_js.Html5 in
+  let state =
+    ref (match arg "tab_text_prelude" with
+         | exception Not_found -> false
+         | "shown" -> true
+         | "hidden" -> false
+         | _ -> failwith "Bad format for argument prelude.") in
+  let prelude_btn = button [] in
+  let prelude_title = h1 [ txt [%i"OCaml prelude"] ;
+                           prelude_btn ] in
+  let prelude_container =
+    pre ~a: [ a_class [ "toplevel-code" ] ]
+      (Learnocaml_toplevel_output.format_ocaml_code prelude) in
+  let update () =
+    if !state then begin
+        Manip.replaceChildren prelude_btn [ txt ("↳ "^[%i"Hide"]) ] ;
+        Manip.SetCss.display prelude_container "" ;
+        Manip.SetCss.top iframe_pane "241px";
+        set_arg "tab_text_prelude" "shown"
+      end else begin
+        Manip.replaceChildren prelude_btn [ txt ("↰ "^[%i"Show"]) ] ;
+        Manip.SetCss.display prelude_container "none" ;
+        Manip.SetCss.top iframe_pane "90px";
+        set_arg "tab_text_prelude" "hidden"
+      end in
+  update () ;
+  Manip.Ev.onclick prelude_btn
+    (fun _ -> state := not !state ; update () ; true) ;
+  Manip.appendChildren prelude_pane
+    [ prelude_title ; prelude_container ]
+
 let setup_prelude_pane ace prelude =
   if prelude = "" then () else
   let editor_pane = find_component "learnocaml-exo-editor-pane" in
@@ -1115,7 +1151,7 @@ module Display_exercise =
         else
           ignore (onclick cid);
         Manip.removeChildren exp;
-        Manip.appendChild exp (txt (if !displayed then "[-]" else "[+]"));
+        Manip.appendChild exp (txt (if !displayed then "[+]" else "[-]"));
         displayed := not !displayed;
         true
       in

src/app/learnocaml_common.mli

@@ -143,7 +143,7 @@ val stars_div: float -> [> Html_types.div ] Tyxml_js.Html5.elt
 
 (** Returns an HTML string expected to be put in an iframe *)
 val exercise_text:
-  Exercise.Meta.t -> Exercise.t -> string
+  Exercise.Meta.t -> Learnocaml_exercise.t -> string
 
 val string_of_exercise_kind: Exercise.Meta.kind -> string
 
@@ -221,6 +221,8 @@ val typecheck :
 
 val set_nickname_div : unit -> unit
 
+val setup_tab_text_prelude_pane : string -> unit
+
 val setup_prelude_pane : 'a Ace.editor -> string -> unit
 
 val get_token : ?has_server:bool -> unit -> Learnocaml_data.student Learnocaml_data.token option Lwt.t

src/app/learnocaml_description_main.ml

@@ -15,10 +15,10 @@ module Exercise_link =
                              a_class cl ]
                         content)
   end
-  
-module Display = Display_exercise(Exercise_link)    
+
+module Display = Display_exercise(Exercise_link)
 open Display
-       
+
 let () =
   run_async_with_log @@ fun () ->
     let id = match Url.Current.path with
@@ -33,12 +33,24 @@ let () =
            retrieve (Learnocaml_api.Exercise (Some token, id))
          in
          init_tabs ();
-         exercise_fetch >>= fun (ex_meta, exo, _deadline) ->
-         (* display exercise questions *)
+         exercise_fetch >>= fun (ex_meta, ex, _deadline) ->
+         let exo = match ex with
+           | Learnocaml_exercise.Subexercise (_,ex) ->
+              (match ex with
+              | [] -> raise Not_found
+              | ex1 :: _ -> Learnocaml_exercise.Exercise ex1)
+           | ex -> ex
+         in
+         (* display exercise questions and prelude *)
+         setup_tab_text_prelude_pane Learnocaml_exercise.(decipher File.prelude exo);
+         let prelude_container = find_component "learnocaml-exo-tab-text-prelude" in
+         let iframe_container = find_component "learnocaml-exo-tab-text-iframe" in
          let text_iframe = Dom_html.createIframe Dom_html.document in
+         Manip.replaceChildren iframe_container [Tyxml_js.Of_dom.of_iFrame text_iframe];
          Manip.replaceChildren text_container
-           Tyxml_js.Html5.[ h1 [ txt ex_meta.title ] ;
-                            Tyxml_js.Of_dom.of_iFrame text_iframe ] ;
+           Tyxml_js.Html5.[ h1 [ txt ex_meta.title] ;
+                            prelude_container;
+                            iframe_container ] ;
          Js.Opt.case
            (text_iframe##.contentDocument)
            (fun () -> failwith "cannot edit iframe document")

src/app/learnocaml_exercise_main.ml

@@ -121,15 +121,20 @@ let () =
   in
   let after_init top =
     exercise_fetch >>= fun (_meta, exo, _deadline) ->
-    begin match Learnocaml_exercise.(decipher File.prelude exo) with
+    let ex = match exo with
+      | Learnocaml_exercise.Exercise ex -> ex
+      | Learnocaml_exercise.Subexercise (_, [] )  -> raise Not_found
+      | Learnocaml_exercise.Subexercise (_id, ex :: _ ) -> ex
+    in
+    begin match Learnocaml_exercise.(decipher File.prelude (Learnocaml_exercise.Exercise ex)) with
       | "" -> Lwt.return true
       | prelude ->
           Learnocaml_toplevel.load ~print_outcome:true top
             ~message: [%i"loading the prelude..."]
             prelude
     end >>= fun r1 ->
     Learnocaml_toplevel.load ~print_outcome:false top
-      (Learnocaml_exercise.(decipher File.prepare exo)) >>= fun r2 ->
+      (Learnocaml_exercise.(decipher File.prepare (Learnocaml_exercise.Exercise ex))) >>= fun r2 ->
     if not r1 || not r2 then failwith [%i"error in prelude"] ;
     Learnocaml_toplevel.set_checking_environment top >>= fun () ->
     Lwt.return () in
@@ -193,11 +198,62 @@ let () =
        d##open_;
        d##write (Js.string (exercise_text ex_meta exo));
        d##close) ;
+
+  (* -------------------  Subexercise navigation -------- *)
+
+  let nav_available = match exo with
+    | Learnocaml_exercise.Exercise _ -> false
+    | Learnocaml_exercise.Subexercise _ -> true
+  in
+  (* Traitement du "sous-index" pour savoir si on peut naviguer *)
+  token >>= fun tok ->
+  retrieve (Learnocaml_api.Exercise_index tok) >>= fun (index,l) ->
+  let navigation_toolbar = find_component "learnocaml-exo-tab-navigation" in
+  let prev_and_next id =
+    let rec loop = function
+      | [] -> assert false
+      | [ _ ] (* assumes single id *) -> None, None
+      | (one, _) :: (two, _) :: _ when id = one -> None, Some two
+      | (one, _) :: (two, _) :: [] when id = two -> Some one, None
+      | (one, _) :: (two, _) :: (three, _) :: _ when id = two -> Some one, Some three
+      |  _ :: rest -> loop rest
+    in loop [id,1] in
+  let prev_button_state = button_state () in
+  let next_button_state = button_state () in
+  begin match prev_and_next id with
+      | None, None ->
+          disable_button prev_button_state ;
+          disable_button next_button_state
+      | Some _, None ->
+          enable_button prev_button_state ;
+          disable_button next_button_state
+      | None, Some _ ->
+          disable_button prev_button_state ;
+          enable_button next_button_state
+      | Some _, Some _ ->
+          enable_button prev_button_state ;
+          enable_button next_button_state
+  end ;
+  let subtitle_field = Tyxml_js.Html5.(h4 ~a: [a_class ["learnocaml-exo-subtitle"]]
+                                         [txt id]) in
+  let button_next = find_component "learnocaml-exo-button-next" in
+  let button_prev = find_component "learnocaml-exo-button-prev" in
+  Manip.appendChild ~before: button_next navigation_toolbar subtitle_field ;
+  if nav_available then
+    (Manip.SetCss.display button_next "";
+     Manip.SetCss.display button_prev "";
+    )
+  else
+    (Manip.SetCss.display button_next "none";
+     Manip.SetCss.display button_prev "none";
+     Manip.SetCss.width subtitle_field "100%";
+    );
+
   (* ---- main toolbar -------------------------------------------------- *)
   let exo_toolbar = find_component "learnocaml-exo-toolbar" in
   let toolbar_button = button ~container: exo_toolbar ~theme: "light" in
   begin toolbar_button
-      ~icon: "list" [%i"Exercises"] @@ fun () ->
+      ~icon: "list" [%i"Exercises"] @@ fun () -> 
     Dom_html.window##.location##assign
       (Js.string (api_server ^ "/index.html#activity=exercises")) ;
     Lwt.return ()
@@ -283,6 +339,10 @@ let () =
         Ace.focus ace ;
         typecheck true
   end ;
+  begin toolbar_button
+      ~icon: "reload" [%i"AllGrade!"] @@ fun () ->
+    typecheck true
+  end;
   Window.onunload (fun _ev -> local_save ace id; true);
   (* ---- return -------------------------------------------------------- *)
   toplevel_launch >>= fun _ ->