Rethink how menus are instantiated in termshark

To make menus work originally, I added a gowid API, via the app struct,
to register a menu. It was on the app because it replaces the app's
top-level view of the UI with a menu which itself then pointed to the
top-level view, but supported a menu overlay if the menu is activated. I
implemented it this way because I needed to generate the lower app
canvas first to return to the menu a list of coordinates which were menu
"sites"; then the overlay will draw the menus at the right positions on the
screen according to the coordinates. BUT - this API is unnecessary
pollution in the app because the menu will work just as well by having
the gowid app author use it as the top-level view. So now I am doing
that, and also giving termshark the ability to layer a widget *above*
the menus. This widget is the new key mapper, to provide vim-like key
macros. Putting it above the menus means the macro-generated key
sequences can be sent to menus too - this allowing macros to invokes
menu options.

ui/ui.go

@@ -57,6 +57,7 @@ import (
 	"github.com/gcla/termshark/v2/widgets/filter"
 	"github.com/gcla/termshark/v2/widgets/hexdumper2"
 	"github.com/gcla/termshark/v2/widgets/ifwidget"
+	"github.com/gcla/termshark/v2/widgets/mapkeys"
 	"github.com/gcla/termshark/v2/widgets/minibuffer"
 	"github.com/gcla/termshark/v2/widgets/resizable"
 	"github.com/gcla/termshark/v2/widgets/rossshark"
@@ -75,6 +76,7 @@ var Goroutinewg *sync.WaitGroup
 // test
 var appViewNoKeys *holder.Widget
 var appView *holder.Widget
+var mbView *holder.Widget
 var mainViewNoKeys *holder.Widget
 var mainView *appkeys.KeyWidget
 var pleaseWaitSpinner *spinner.Widget
@@ -123,6 +125,7 @@ var loadProgress *progress.Widget
 var loadSpinner *spinner.Widget
 var savedListBoxWidgetHolder *holder.Widget
 var singlePacketViewMsgHolder *holder.Widget // either empty or "loading..."
+var keyMapper *mapkeys.Widget
 
 var tabViewsForward map[gowid.IWidget]gowid.IWidget
 var tabViewsBackward map[gowid.IWidget]gowid.IWidget
@@ -3238,7 +3241,10 @@ func Build() (*gowid.App, error) {
 		),
 	}
 
-	Fin = rossshark.New(appViewWithKeys)
+	// For minibuffer
+	mbView = holder.New(appViewWithKeys)
+
+	Fin = rossshark.New(mbView)
 
 	if !termshark.ConfBool("main.disable-shark-fin", false) {
 		steerableFin := appkeys.NewMouse(
@@ -3276,12 +3282,41 @@ func Build() (*gowid.App, error) {
 
 		appView = holder.New(steerableFin)
 	} else {
-		appView = holder.New(appViewWithKeys)
+		appView = holder.New(mbView)
+	}
+
+	var lastMenu gowid.IWidget = appView
+	menus := []gowid.IMenuCompatible{
+		savedMenu,
+		analysisMenu,
+		generalMenu,
+		conversationMenu,
+		filterConvsMenu1,
+		filterConvsMenu2,
+	}
+
+	menus = append(menus, FilterWidget.Menus()...)
+
+	for _, w := range menus {
+		w.SetSubWidget(lastMenu, app)
+		lastMenu = w
+	}
+
+	keyMapper = mapkeys.New(lastMenu)
+	keyMappings := termshark.LoadKeyMappings()
+	for _, km := range keyMappings {
+		log.Infof("Applying keymapping %v --> %v", km.From, km.To)
+		keyMapper.AddMapping(km.From, km.To, app)
+	}
+
+	if err = termshark.LoadGlobalMarks(globalMarksMap); err != nil {
+		// Not fatal
+		log.Error(err)
 	}
 
 	// Create app, etc, but don't init screen which sets ICANON, etc
 	app, err = gowid.NewApp(gowid.AppArgs{
-		View:         appView,
+		View:         keyMapper,
 		Palette:      palette,
 		DontActivate: true,
 		Log:          log.StandardLogger(),
@@ -3291,16 +3326,6 @@ func Build() (*gowid.App, error) {
 		return nil, err
 	}
 
-	for _, m := range FilterWidget.Menus() {
-		app.RegisterMenu(m)
-	}
-	app.RegisterMenu(savedMenu)
-	app.RegisterMenu(analysisMenu)
-	app.RegisterMenu(generalMenu)
-	app.RegisterMenu(conversationMenu)
-	app.RegisterMenu(filterConvsMenu1)
-	app.RegisterMenu(filterConvsMenu2)
-
 	gowid.SetFocusPath(mainview, mainviewPaths[0], app)
 	gowid.SetFocusPath(altview1, altview1Paths[0], app)
 	gowid.SetFocusPath(altview2, altview2Paths[0], app)