triggerbox: rename sidechain port when track's name chanes

Just like PluginInsert::update_sidechain_name, the name is
implicitly set, using the owning route's name, suffixed with the
[i18n localized] Processor name.

This fixes an issue if a track is renamed and a new track with
the old name is created. This commonly happens during File Import:
For each ImportAsTrack a generic named track (e.g. "Audio") is created
before it is renamed.

Previously this lead to
Failed to register port "Audio 1-trig/midi_in 1", reason is unknown from here

libs/ardour/ardour/triggerbox.h

@@ -541,7 +541,8 @@ class LIBARDOUR_API TriggerBox : public Processor
 	TriggerPtr get_next_trigger ();
 	TriggerPtr peek_next_trigger ();
 
-	void add_midi_sidechain (std::string const & name);
+	void add_midi_sidechain ();
+	void update_sidechain_name ();
 
 	bool pass_thru() const { return _requests.pass_thru; }
 	void set_pass_thru (bool yn);

libs/ardour/route.cc

@@ -3160,8 +3160,11 @@ Route::set_processor_state (const XMLNode& node, int version)
 			cerr << "Seen triggerbox!\n";
 			if (!_triggerbox) {
 				_triggerbox.reset (new TriggerBox (_session, _default_type));
+				_triggerbox->set_owner (this);
 			}
 			_triggerbox->set_state (**niter, version);
+			_triggerbox->update_sidechain_name ();
+
 			new_order.push_back (_triggerbox);
 		} else {
 			set_processor_state (**niter, version, prop, new_order, must_configure);
@@ -4581,6 +4584,10 @@ Route::set_name (const string& str)
 		pi->update_sidechain_name ();
 	}
 
+	if (_triggerbox) {
+		_triggerbox->update_sidechain_name ();
+	}
+
 	bool ret = (_input->set_name(newname) && _output->set_name(newname));
 
 	if (ret) {

libs/ardour/session.cc

@@ -2740,7 +2740,7 @@ Session::new_audio_track (int input_channels, int output_channels, RouteGroup* r
 				 * data type is AUDIO, the triggerbox will need
 				 * a sidehcain MIDI input to be able to be MIDI controlled
 				 */
-				tb->add_midi_sidechain (track->name());
+				tb->add_midi_sidechain ();
 				track->presentation_info ().set_trigger_track (true);
 			}
 

libs/ardour/triggerbox.cc

@@ -2158,10 +2158,11 @@ TriggerBox::trigger (Triggers::size_type n)
 }
 
 void
-TriggerBox::add_midi_sidechain (std::string const & name)
+TriggerBox::add_midi_sidechain ()
 {
+	assert (owner());
 	if (!_sidechain) {
-		_sidechain.reset (new SideChain (_session, name + "-trig"));
+		_sidechain.reset (new SideChain (_session, string_compose ("%1/%2", owner()->name(), name ())));
 		_sidechain->activate ();
 		_sidechain->input()->add_port ("", owner(), DataType::MIDI); // add a port, don't connect.
 		boost::shared_ptr<Port> p = _sidechain->input()->nth (0);
@@ -2174,6 +2175,16 @@ TriggerBox::add_midi_sidechain (std::string const & name)
 	}
 }
 
+void
+TriggerBox::update_sidechain_name ()
+{
+	if (!_sidechain) {
+		return;
+	}
+	assert (owner());
+	_sidechain->set_name (string_compose ("%1/%2", owner()->name(), name ()));
+}
+
 bool
 TriggerBox::can_support_io_configuration (const ChanCount& in, ChanCount& out)
 {
@@ -2831,12 +2842,7 @@ TriggerBox::get_state (void)
 	node.add_child_nocopy (*trigger_child);
 
 	if (_sidechain) {
-		XMLNode* scnode = new XMLNode (X_("Sidechain"));
+		node.add_child_nocopy (_sidechain->get_state ());
-		std::string port_name = _sidechain->input()->nth (0)->name();
-		port_name = port_name.substr (0, port_name.find ('-'));
-		scnode->set_property (X_("name"), port_name);
-		scnode->add_child_nocopy (_sidechain->get_state());
-		node.add_child_nocopy (*scnode);
 	}
 
 	return node;
@@ -2881,14 +2887,12 @@ TriggerBox::set_state (const XMLNode& node, int version)
 		}
 	}
 
-	XMLNode* scnode = node.child (X_("Sidechain"));
+	/* sidechain is a Processor (IO) */
-
+	XMLNode* scnode = node.child (Processor::state_node_name.c_str ());
 	if (scnode) {
-		std::string name;
+		add_midi_sidechain ();
-		scnode->get_property (X_("name"), name);
-		add_midi_sidechain (name);
 		assert (_sidechain);
-		_sidechain->set_state (*scnode->children().front(), version);
+		_sidechain->set_state (*scnode, version);
 	}
 
 	return 0;