From a74de1398f9920f31bf4c512fb3b2abe28e516b9 Mon Sep 17 00:00:00 2001
From: Paul Licameli <paul.licameli@audacityteam.org>
Date: Thu, 15 Oct 2020 14:29:34 -0400
Subject: [PATCH] StereoToMono also in effects module, but should it remain an
 effect?

---
 .../effects/mod-effect-classes/CMakeLists.txt |  2 +
 .../mod-effect-classes}/StereoToMono.cpp      | 48 ++++++++++++++++++-
 .../mod-effect-classes}/StereoToMono.h        |  0
 src/CMakeLists.txt                            |  2 -
 src/menus/TrackMenus.cpp                      | 26 +---------
 5 files changed, 50 insertions(+), 28 deletions(-)
 rename {src/effects => modules/effects/mod-effect-classes}/StereoToMono.cpp (77%)
 rename {src/effects => modules/effects/mod-effect-classes}/StereoToMono.h (100%)

diff --git a/modules/effects/mod-effect-classes/CMakeLists.txt b/modules/effects/mod-effect-classes/CMakeLists.txt
index e70b59113152..eb03d6e65bcd 100644
--- a/modules/effects/mod-effect-classes/CMakeLists.txt
+++ b/modules/effects/mod-effect-classes/CMakeLists.txt
@@ -73,6 +73,8 @@ list( APPEND SOURCES
    ScienFilter.h
    Silence.cpp
    Silence.h
+   StereoToMono.cpp
+   StereoToMono.h
    ToneGen.cpp
    ToneGen.h
    TruncSilence.cpp
diff --git a/src/effects/StereoToMono.cpp b/modules/effects/mod-effect-classes/StereoToMono.cpp
similarity index 77%
rename from src/effects/StereoToMono.cpp
rename to modules/effects/mod-effect-classes/StereoToMono.cpp
index f3714b9d7f90..e2814204f613 100644
--- a/src/effects/StereoToMono.cpp
+++ b/modules/effects/mod-effect-classes/StereoToMono.cpp
@@ -13,7 +13,6 @@
 
 *//*******************************************************************/
 
-
 #include "StereoToMono.h"
 #include "EffectOutputTracks.h"
 #include "LoadEffects.h"
@@ -179,3 +178,50 @@ bool EffectStereoToMono::IsHiddenFromMenus() const
 {
    return true;
 }
+
+// Attach a menu item
+#include "CommonCommandFlags.h"
+#include "PluginManager.h"
+#include "CommandManager.h"
+#include "effects/EffectManager.h"
+#include "effects/EffectUI.h"
+
+namespace {
+void OnStereoToMono(const CommandContext &context)
+{
+   EffectUI::DoEffect(
+      EffectManager::Get().GetEffectByIdentifier(wxT("StereoToMono")),
+      context,
+      EffectManager::kConfigured);
+}
+
+using namespace MenuRegistry;
+auto MenuItem()
+{
+   static auto item = std::shared_ptr{
+   // Delayed evaluation
+   // Stereo to Mono is an oddball command that is also subject to control
+   // by the plug-in manager, as if an effect.  Decide whether to show or
+   // hide it.
+   Items( "",
+      [](AudacityProject&) -> std::unique_ptr<CommandItem> {
+         const PluginID ID =
+            EffectManager::Get().GetEffectByIdentifier(wxT("StereoToMono"));
+         const PluginDescriptor *plug = PluginManager::Get().GetPlugin(ID);
+         if (plug && plug->IsEnabled())
+            return Command( wxT("Stereo to Mono"),
+               XXO("Mix Stereo Down to &Mono"), OnStereoToMono,
+               AudioIONotBusyFlag() | StereoRequiredFlag() |
+                  WaveTracksSelectedFlag(), Options{} );
+         else
+            return {};
+      }
+   ) };
+   return item;
+}
+
+AttachedItem sAttachment{
+   Indirect(MenuItem()),
+   { wxT("Tracks/Mix/Mix"), { OrderingHint::Begin, {} } }
+};
+}
diff --git a/src/effects/StereoToMono.h b/modules/effects/mod-effect-classes/StereoToMono.h
similarity index 100%
rename from src/effects/StereoToMono.h
rename to modules/effects/mod-effect-classes/StereoToMono.h
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index f395f761e74c..4e77f24b5a63 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -331,8 +331,6 @@ list( APPEND SOURCES
       effects/StatefulPerTrackEffect.h
       effects/StatelessPerTrackEffect.cpp
       effects/StatelessPerTrackEffect.h
-      effects/StereoToMono.cpp
-      effects/StereoToMono.h
       effects/TwoPassSimpleMono.cpp
       effects/TwoPassSimpleMono.h
 
diff --git a/src/menus/TrackMenus.cpp b/src/menus/TrackMenus.cpp
index 13fda8f12abc..f9689df2ea7a 100644
--- a/src/menus/TrackMenus.cpp
+++ b/src/menus/TrackMenus.cpp
@@ -548,14 +548,6 @@ namespace {
 
 // Menu handler functions
 
-void OnStereoToMono(const CommandContext &context)
-{
-   EffectUI::DoEffect(
-      EffectManager::Get().GetEffectByIdentifier(wxT("StereoToMono")),
-      context,
-      EffectManager::kConfigured);
-}
-
 void OnMixAndRender(const CommandContext &context)
 {
    auto &project = context.project;
@@ -1130,24 +1122,8 @@ auto TracksMenu()
 
       //////////////////////////////////////////////////////////////////////////
 
-      Section( "",
+      Section( "Mix",
          Menu( wxT("Mix"), XXO("Mi&x"),
-            // Delayed evaluation
-            // Stereo to Mono is an oddball command that is also subject to control
-            // by the plug-in manager, as if an effect.  Decide whether to show or
-            // hide it.
-            [](AudacityProject&) -> std::unique_ptr<CommandItem> {
-               const PluginID ID =
-                  EffectManager::Get().GetEffectByIdentifier(wxT("StereoToMono"));
-               const PluginDescriptor *plug = PluginManager::Get().GetPlugin(ID);
-               if (plug && plug->IsEnabled())
-                  return Command( wxT("Stereo to Mono"),
-                     XXO("Mix Stereo Down to &Mono"), OnStereoToMono,
-                     AudioIONotBusyFlag() | StereoRequiredFlag() |
-                        WaveTracksSelectedFlag(), Options{} );
-               else
-                  return {};
-            },
             Command( wxT("MixAndRender"), XXO("Mi&x and Render"),
                OnMixAndRender,
                AudioIONotBusyFlag() | WaveTracksSelectedFlag() ),