Rework the preset menu system to permit submenus.

To do this, I've completely replaced the API between mid-end and front
end, so any downstream front end maintainers will have to do some
rewriting of their own (sorry). I've done the necessary work in all
five of the front ends I keep in-tree here - Windows, GTK, OS X,
Javascript/Emscripten, and Java/NestedVM - and I've done it in various
different styles (as each front end found most convenient), so that
should provide a variety of sample code to show downstreams how, if
they should need it.

I've left in the old puzzle back-end API function to return a flat
list of presets, so for the moment, all the puzzle backends are
unchanged apart from an extra null pointer appearing in their
top-level game structure. In a future commit I'll actually use the new
feature in a puzzle; perhaps in the further future it might make sense
to migrate all the puzzles to the new API and stop providing back ends
with two alternative ways of doing things, but this seemed like enough
upheaval for one day.

1 files changed, 74 insertions, 52 deletions

diff --git a/gtk.c b/gtk.c
index ab3ad8b..c5e3d1c 100644
--- a/gtk.c
+++ b/gtk.c
@@ -182,7 +182,6 @@ struct frontend {
     char *filesel_name;
 #endif
     GSList *preset_radio;
-    int n_preset_menu_items;
     int preset_threaded;
     GtkWidget *preset_custom;
     GtkWidget *copy_menu_item;
@@ -1884,20 +1883,22 @@ static void changed_preset(frontend *fe)
 	    TRUE);
     } else {
 	GSList *gs = fe->preset_radio;
-	int i = fe->n_preset_menu_items - 1 - n;
-	if (fe->preset_custom)
-	    gs = gs->next;
-	while (i && gs) {
-	    i--;
-	    gs = gs->next;
-	}
-	if (gs) {
-	    gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(gs->data),
-					   TRUE);
-	} else for (gs = fe->preset_radio; gs; gs = gs->next) {
-	    gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(gs->data),
-					   FALSE);
-	}
+        GSList *found = NULL;
+
+        for (gs = fe->preset_radio; gs; gs = gs->next) {
+            struct preset_menu_entry *entry =
+                (struct preset_menu_entry *)g_object_get_data(
+                    G_OBJECT(gs->data), "user-data");
+
+            if (entry && entry->id != n)
+                gtk_check_menu_item_set_active(
+                    GTK_CHECK_MENU_ITEM(gs->data), FALSE);
+            else
+                found = gs;
+        }
+        if (found)
+            gtk_check_menu_item_set_active(
+                GTK_CHECK_MENU_ITEM(found->data), FALSE);
     }
     fe->preset_threaded = FALSE;
 
@@ -2019,14 +2020,15 @@ static void resize_fe(frontend *fe)
 static void menu_preset_event(GtkMenuItem *menuitem, gpointer data)
 {
     frontend *fe = (frontend *)data;
-    game_params *params =
-        (game_params *)g_object_get_data(G_OBJECT(menuitem), "user-data");
+    struct preset_menu_entry *entry =
+        (struct preset_menu_entry *)g_object_get_data(
+            G_OBJECT(menuitem), "user-data");
 
     if (fe->preset_threaded ||
 	(GTK_IS_CHECK_MENU_ITEM(menuitem) &&
 	 !gtk_check_menu_item_get_active(GTK_CHECK_MENU_ITEM(menuitem))))
 	return;
-    midend_set_params(fe->me, params);
+    midend_set_params(fe->me, entry->params);
     midend_new_game(fe->me);
     changed_preset(fe);
     resize_fe(fe);
@@ -2383,6 +2385,36 @@ static void add_menu_separator(GtkContainer *cont)
     gtk_widget_show(menuitem);
 }
 
+static void populate_gtk_preset_menu(frontend *fe, struct preset_menu *menu,
+                                     GtkWidget *gtkmenu)
+{
+    int i;
+
+    for (i = 0; i < menu->n_entries; i++) {
+        struct preset_menu_entry *entry = &menu->entries[i];
+        GtkWidget *menuitem;
+
+        if (entry->params) {
+            menuitem = gtk_radio_menu_item_new_with_label(
+                fe->preset_radio, entry->title);
+            fe->preset_radio = gtk_radio_menu_item_get_group(
+                GTK_RADIO_MENU_ITEM(menuitem));
+            g_object_set_data(G_OBJECT(menuitem), "user-data", entry);
+            g_signal_connect(G_OBJECT(menuitem), "activate",
+                             G_CALLBACK(menu_preset_event), fe);
+        } else {
+            GtkWidget *submenu;
+            menuitem = gtk_menu_item_new_with_label(entry->title);
+            submenu = gtk_menu_new();
+            gtk_menu_item_set_submenu(GTK_MENU_ITEM(menuitem), submenu);
+            populate_gtk_preset_menu(fe, entry->submenu, submenu);
+        }
+
+        gtk_container_add(GTK_CONTAINER(gtkmenu), menuitem);
+        gtk_widget_show(menuitem);
+    }
+}
+
 enum { ARG_EITHER, ARG_SAVE, ARG_ID }; /* for argtype */
 
 static frontend *new_window(char *arg, int argtype, char **error)
@@ -2395,6 +2427,7 @@ static frontend *new_window(char *arg, int argtype, char **error)
     char errbuf[1024];
     extern char *const *const xpm_icons[];
     extern const int n_xpm_icons;
+    struct preset_menu *preset_menu;
 
     fe = snew(frontend);
 #if GTK_CHECK_VERSION(3,20,0)
@@ -2546,11 +2579,11 @@ static frontend *new_window(char *arg, int argtype, char **error)
 
     fe->preset_radio = NULL;
     fe->preset_custom = NULL;
-    fe->n_preset_menu_items = 0;
     fe->preset_threaded = FALSE;
-    if ((n = midend_num_presets(fe->me)) > 0 || thegame.can_configure) {
+
+    preset_menu = midend_get_presets(fe->me, NULL);
+    if (preset_menu->n_entries > 0 || thegame.can_configure) {
         GtkWidget *submenu;
-        int i;
 
         menuitem = gtk_menu_item_new_with_mnemonic("_Type");
         gtk_container_add(GTK_CONTAINER(fe->menubar), menuitem);
@@ -2559,23 +2592,7 @@ static frontend *new_window(char *arg, int argtype, char **error)
         submenu = gtk_menu_new();
         gtk_menu_item_set_submenu(GTK_MENU_ITEM(menuitem), submenu);
 
-        for (i = 0; i < n; i++) {
-            char *name;
-            game_params *params;
-
-            midend_fetch_preset(fe->me, i, &name, &params);
-
-	    menuitem =
-		gtk_radio_menu_item_new_with_label(fe->preset_radio, name);
-	    fe->preset_radio =
-		gtk_radio_menu_item_get_group(GTK_RADIO_MENU_ITEM(menuitem));
-	    fe->n_preset_menu_items++;
-            gtk_container_add(GTK_CONTAINER(submenu), menuitem);
-            g_object_set_data(G_OBJECT(menuitem), "user-data", params);
-            g_signal_connect(G_OBJECT(menuitem), "activate",
-                             G_CALLBACK(menu_preset_event), fe);
-            gtk_widget_show(menuitem);
-        }
+        populate_gtk_preset_menu(fe, preset_menu, submenu);
 
 	if (thegame.can_configure) {
 	    menuitem = fe->preset_custom =
@@ -2826,6 +2843,22 @@ char *fgetline(FILE *fp)
     return ret;
 }
 
+static void list_presets_from_menu(struct preset_menu *menu)
+{
+    int i;
+
+    for (i = 0; i < menu->n_entries; i++) {
+        if (menu->entries[i].params) {
+            char *paramstr = thegame.encode_params(
+                menu->entries[i].params, TRUE);
+            printf("%s %s\n", paramstr, menu->entries[i].title);
+            sfree(paramstr);
+        } else {
+            list_presets_from_menu(menu->entries[i].submenu);
+        }
+    }
+}
+
 int main(int argc, char **argv)
 {
     char *pname = argv[0];
@@ -3229,23 +3262,12 @@ int main(int argc, char **argv)
          * Another specialist mode which causes the puzzle to list the
          * game_params strings for all its preset configurations.
          */
-        int i, npresets;
         midend *me;
+        struct preset_menu *menu;
 
 	me = midend_new(NULL, &thegame, NULL, NULL);
-        npresets = midend_num_presets(me);
-
-        for (i = 0; i < npresets; i++) {
-            game_params *params;
-            char *name, *paramstr;
-
-            midend_fetch_preset(me, i, &name, &params);
-            paramstr = thegame.encode_params(params, TRUE);
-
-            printf("%s %s\n", paramstr, name);
-            sfree(paramstr);
-        }
-
+        menu = midend_get_presets(me, NULL);
+        list_presets_from_menu(menu);
 	midend_free(me);
         return 0;
     } else {