livetrax/libs/surfaces/generic_midi/generic_midi_control_protocol.cc

/*
 * Copyright (C) 2006-2010 David Robillard <d@drobilla.net>
 * Copyright (C) 2006-2018 Paul Davis <paul@linuxaudiosystems.com>
 * Copyright (C) 2008-2012 Carl Hetherington <carl@carlh.net>
 * Copyright (C) 2012-2017 Tim Mayberry <mojofunk@gmail.com>
 * Copyright (C) 2015-2019 Robin Gareus <robin@gareus.org>
 * Copyright (C) 2015 Len Ovens <len@ovenwerks.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <stdint.h>

#include <sstream>
#include <algorithm>

#ifdef COMPILER_MSVC
#include <io.h> // Microsoft's nearest equivalent to <unistd.h>
#include <ardourext/misc.h>
#else
#include <regex.h>
#endif

#include <glibmm/fileutils.h>
#include <glibmm/miscutils.h>

#include "pbd/compose.h"
#include "pbd/convert.h"
#include "pbd/error.h"
#include "pbd/failed_constructor.h"
#include "pbd/file_utils.h"
#include "pbd/strsplit.h"
#include "pbd/types_convert.h"
#include "pbd/xml++.h"

#include "midi++/port.h"

#include "ardour/async_midi_port.h"
#include "ardour/audioengine.h"
#include "ardour/auditioner.h"
#include "ardour/filesystem_paths.h"
#include "ardour/session.h"
#include "ardour/midi_ui.h"
#include "ardour/plugin_insert.h"
#include "ardour/rc_configuration.h"
#include "ardour/midiport_manager.h"
#include "ardour/debug.h"

#include "generic_midi_control_protocol.h"
#include "midicontrollable.h"
#include "midifunction.h"
#include "midiaction.h"

#include "pbd/abstract_ui.cc" // instantiate template

#include "pbd/i18n.h"

using namespace ARDOUR;
using namespace PBD;
using namespace Glib;
using namespace std;

GenericMidiControlProtocol::GenericMidiControlProtocol (Session& s)
	: ControlProtocol (s, _("Generic MIDI"))
	, AbstractUI<GenericMIDIRequest> (name())
	, connection_state (ConnectionState (0))
	, _motorised (false)
	, _threshold (10)
	, gui (0)
{
	boost::shared_ptr<ARDOUR::Port> inp;
	boost::shared_ptr<ARDOUR::Port> outp;

	inp  = AudioEngine::instance()->register_input_port (DataType::MIDI, _("MIDI Control In"), true);
	outp = AudioEngine::instance()->register_output_port (DataType::MIDI, _("MIDI Control Out"), true);

	if (inp == 0 || outp == 0) {
		throw failed_constructor();
	}

	_input_port = boost::dynamic_pointer_cast<AsyncMIDIPort>(inp);
	_output_port = boost::dynamic_pointer_cast<AsyncMIDIPort>(outp);

	_input_bundle.reset (new ARDOUR::Bundle (_("Generic MIDI Control In"), true));
	_output_bundle.reset (new ARDOUR::Bundle (_("Generic MIDI Control Out"), false));

	_input_bundle->add_channel (
		"",
		ARDOUR::DataType::MIDI,
		session->engine().make_port_name_non_relative (inp->name())
		);

	_output_bundle->add_channel (
		"",
		ARDOUR::DataType::MIDI,
		session->engine().make_port_name_non_relative (outp->name())
		);

	session->BundleAddedOrRemoved ();

	do_feedback = false;
	_feedback_interval = 10000; // microseconds
	last_feedback_time = 0;

	_current_bank = 0;
	_bank_size = 0;

	/* these signals are emitted by our event loop thread
	 * and we may as well handle them right there in the same the same
	 * thread
	 */

	Controllable::StartLearning.connect_same_thread (*this, boost::bind (&GenericMidiControlProtocol::start_learning, this, _1));
	Controllable::StopLearning.connect_same_thread (*this, boost::bind (&GenericMidiControlProtocol::stop_learning, this, _1));

	/* this signal is emitted by the process() callback, and if
	 * send_feedback() is going to do anything, it should do it in the
	 * context of the process() callback itself.
	 */

	Session::SendFeedback.connect_same_thread (*this, boost::bind (&GenericMidiControlProtocol::send_feedback, this));

	/* this one is cross-thread */

	PresentationInfo::Change.connect (*this, MISSING_INVALIDATOR, boost::bind (&GenericMidiControlProtocol::reset_controllables, this), this);

	/* Catch port connections and disconnections (cross-thread) */
	ARDOUR::AudioEngine::instance()->PortConnectedOrDisconnected.connect (_port_connection, MISSING_INVALIDATOR,
	                                                                      boost::bind (&GenericMidiControlProtocol::connection_handler, this, _1, _2, _3, _4, _5),
	                                                                      this);

	reload_maps ();
}

GenericMidiControlProtocol::~GenericMidiControlProtocol ()
{
	if (_input_port) {
		DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("unregistering input port %1\n", boost::shared_ptr<ARDOUR::Port>(_input_port)->name()));
		Glib::Threads::Mutex::Lock em (AudioEngine::instance()->process_lock());
		AudioEngine::instance()->unregister_port (_input_port);
		_input_port.reset ();
	}

	if (_output_port) {
		_output_port->drain (10000,  250000); /* check every 10 msecs, wait up to 1/4 second for the port to drain */
		DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("unregistering output port %1\n", boost::shared_ptr<ARDOUR::Port>(_output_port)->name()));
		Glib::Threads::Mutex::Lock em (AudioEngine::instance()->process_lock());
		AudioEngine::instance()->unregister_port (_output_port);
		_output_port.reset ();
	}

	drop_all ();
	tear_down_gui ();
}

list<boost::shared_ptr<ARDOUR::Bundle> >
GenericMidiControlProtocol::bundles ()
{
	list<boost::shared_ptr<ARDOUR::Bundle> > b;

	if (_input_bundle) {
		b.push_back (_input_bundle);
		b.push_back (_output_bundle);
	}

	return b;
}


static const char * const midimap_env_variable_name = "ARDOUR_MIDIMAPS_PATH";
static const char* const midi_map_dir_name = "midi_maps";
static const char* const midi_map_suffix = ".map";

Searchpath
system_midi_map_search_path ()
{
	bool midimap_path_defined = false;
	std::string spath_env (Glib::getenv (midimap_env_variable_name, midimap_path_defined));

	if (midimap_path_defined) {
		return spath_env;
	}

	Searchpath spath (ardour_data_search_path());
	spath.add_subdirectory_to_paths(midi_map_dir_name);
	return spath;
}

static std::string
user_midi_map_directory ()
{
	return Glib::build_filename (user_config_directory(), midi_map_dir_name);
}

static bool
midi_map_filter (const string &str, void* /*arg*/)
{
	return (str.length() > strlen(midi_map_suffix) &&
		str.find (midi_map_suffix) == (str.length() - strlen (midi_map_suffix)));
}

void
GenericMidiControlProtocol::reload_maps ()
{
	vector<string> midi_maps;
	Searchpath spath (system_midi_map_search_path());
	spath += user_midi_map_directory ();

	find_files_matching_filter (midi_maps, spath, midi_map_filter, 0, false, true);

	if (midi_maps.empty()) {
		cerr << "No MIDI maps found using " << spath.to_string() << endl;
		return;
	}

	for (vector<string>::iterator i = midi_maps.begin(); i != midi_maps.end(); ++i) {
		string fullpath = *i;

		XMLTree tree;

		if (!tree.read (fullpath.c_str())) {
			continue;
		}

		MapInfo mi;

		std::string str;
		if (!tree.root()->get_property ("name", str)) {
			continue;
		}

		mi.name = str;
		mi.path = fullpath;

		map_info.push_back (mi);
	}
}

void
GenericMidiControlProtocol::drop_all ()
{
	DEBUG_TRACE (DEBUG::GenericMidi, "Drop all bindings\n");
	Glib::Threads::Mutex::Lock lm (pending_lock);
	Glib::Threads::Mutex::Lock lm2 (controllables_lock);

	for (MIDIControllables::iterator i = controllables.begin(); i != controllables.end(); ++i) {
		delete *i;
	}
	controllables.clear ();

	for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ++i) {
		(*i)->connection.disconnect();
		if ((*i)->own_mc) {
			delete (*i)->mc;
		}
		delete *i;
	}
	pending_controllables.clear ();

	for (MIDIFunctions::iterator i = functions.begin(); i != functions.end(); ++i) {
		delete *i;
	}
	functions.clear ();

	for (MIDIActions::iterator i = actions.begin(); i != actions.end(); ++i) {
		delete *i;
	}
	actions.clear ();
}

void
GenericMidiControlProtocol::drop_bindings ()
{
	DEBUG_TRACE (DEBUG::GenericMidi, "Drop bindings, leave learned\n");
	Glib::Threads::Mutex::Lock lm2 (controllables_lock);

	for (MIDIControllables::iterator i = controllables.begin(); i != controllables.end(); ) {
		if (!(*i)->learned()) {
			delete *i;
			i = controllables.erase (i);
		} else {
			++i;
		}
	}

	for (MIDIFunctions::iterator i = functions.begin(); i != functions.end(); ++i) {
		delete *i;
	}
	functions.clear ();

	_current_binding = "";
	_bank_size = 0;
	_current_bank = 0;
}

void
GenericMidiControlProtocol::do_request (GenericMIDIRequest* req)
{
	if (req->type == CallSlot) {

		call_slot (MISSING_INVALIDATOR, req->the_slot);

	} else if (req->type == Quit) {

		stop ();
	}
}

int
GenericMidiControlProtocol::stop ()
{
	BaseUI::quit ();

	return 0;
}

void
GenericMidiControlProtocol::thread_init ()
{
	pthread_set_name (event_loop_name().c_str());

	PBD::notify_event_loops_about_thread_creation (pthread_self(), event_loop_name(), 2048);
	ARDOUR::SessionEvent::create_per_thread_pool (event_loop_name(), 128);

	set_thread_priority ();
}

int
GenericMidiControlProtocol::set_active (bool yn)
{
	DEBUG_TRACE (DEBUG::GenericMidi, string_compose("GenericMIDI::set_active init with yn: '%1'\n", yn));

	if (yn == active()) {
		return 0;
	}

	if (yn) {
		BaseUI::run ();
	} else {
		BaseUI::quit ();
	}

	ControlProtocol::set_active (yn);

	DEBUG_TRACE (DEBUG::GenericMidi, string_compose("GenericMIDI::set_active done with yn: '%1'\n", yn));

	return 0;
}

void
GenericMidiControlProtocol::set_feedback_interval (microseconds_t ms)
{
	_feedback_interval = ms;
}

void
GenericMidiControlProtocol::send_feedback ()
{
	/* This is executed in RT "process" context", so no blocking calls
	 */

	if (!do_feedback) {
		return;
	}

	microseconds_t now = get_microseconds ();

	if (last_feedback_time != 0) {
		if ((now - last_feedback_time) < _feedback_interval) {
			return;
		}
	}

	_send_feedback ();

	last_feedback_time = now;
}

void
GenericMidiControlProtocol::_send_feedback ()
{
	/* This is executed in RT "process" context", so no blocking calls
	 */

	const int32_t bufsize = 16 * 1024; /* XXX too big */
	MIDI::byte buf[bufsize];
	int32_t bsize = bufsize;

	/* XXX: due to bugs in some ALSA / JACK MIDI bridges, we have to do separate
	   writes for each controllable here; if we send more than one MIDI message
	   in a single jack_midi_event_write then some bridges will only pass the
	   first on to ALSA.
	*/

	Glib::Threads::Mutex::Lock lm (controllables_lock, Glib::Threads::TRY_LOCK);
	if (!lm.locked ()) {
		return;
	}

	for (MIDIControllables::iterator r = controllables.begin(); r != controllables.end(); ++r) {
		MIDI::byte* end = (*r)->write_feedback (buf, bsize);
		if (end != buf) {
			_output_port->write (buf, (int32_t) (end - buf), 0);
		}
	}
}

bool
GenericMidiControlProtocol::start_learning (boost::weak_ptr <Controllable> wc)
{
	boost::shared_ptr<Controllable> c = wc.lock ();
	if (!c) {
		return false;
	}

	Glib::Threads::Mutex::Lock lm2 (controllables_lock);
	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("Learn binding: Controlable number: %1\n", c));

	/* drop any existing mappings for the same controllable for which
	 * learning has just started.
	 */

	MIDIControllables::iterator tmp;
	for (MIDIControllables::iterator i = controllables.begin(); i != controllables.end(); ) {
		tmp = i;
		++tmp;
		if ((*i)->get_controllable() == c) {
			delete (*i);
			controllables.erase (i);
		}
		i = tmp;
	}

	/* check pending controllables (those for which a learn is underway) to
	 * see if it is for the same one for which learning has just started.
	 */

	{
		Glib::Threads::Mutex::Lock lm (pending_lock);

		for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ) {
			if (((*i)->mc)->get_controllable() == c) {
				(*i)->connection.disconnect();
				if ((*i)->own_mc) {
					delete (*i)->mc;
				}
				delete *i;
				i = pending_controllables.erase (i);
			} else {
				++i;
			}
		}
	}

	MIDIControllable* mc = 0;
	bool own_mc = false;

	for (MIDIControllables::iterator i = controllables.begin(); i != controllables.end(); ++i) {
		if ((*i)->get_controllable() && ((*i)->get_controllable()->id() == c->id())) {
			mc = *i;
			break;
		}
	}

	if (!mc) {
		mc = new MIDIControllable (this, *_input_port->parser(), c, false);
		own_mc = true;
	}

	/* stuff the new controllable into pending */

	{
		Glib::Threads::Mutex::Lock lm (pending_lock);

		MIDIPendingControllable* element = new MIDIPendingControllable (mc, own_mc);
		c->LearningFinished.connect_same_thread (element->connection, boost::bind (&GenericMidiControlProtocol::learning_stopped, this, mc));

		pending_controllables.push_back (element);
	}
	mc->learn_about_external_control ();
	return true;
}

void
GenericMidiControlProtocol::learning_stopped (MIDIControllable* mc)
{
	Glib::Threads::Mutex::Lock lm (pending_lock);
	Glib::Threads::Mutex::Lock lm2 (controllables_lock);

	for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ) {
		if ( (*i)->mc == mc) {
			(*i)->connection.disconnect();
			delete *i;
			i = pending_controllables.erase(i);
		} else {
			++i;
		}
	}

	/* add the controllable for which learning stopped to our list of
	 * controllables
	 */

	controllables.push_back (mc);
}

void
GenericMidiControlProtocol::stop_learning (boost::weak_ptr<PBD::Controllable> wc)
{
	boost::shared_ptr<Controllable> c = wc.lock ();
	if (!c) {
		return;
	}

	Glib::Threads::Mutex::Lock lm (pending_lock);
	Glib::Threads::Mutex::Lock lm2 (controllables_lock);
	MIDIControllable* dptr = 0;

	/* learning timed out, and we've been told to consider this attempt to learn to be cancelled. find the
	   relevant MIDIControllable and remove it from the pending list.
	*/

	for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ++i) {
		if (((*i)->mc)->get_controllable() == c) {
			(*i)->mc->stop_learning ();
			dptr = (*i)->mc;
			(*i)->connection.disconnect();

			delete *i;
			pending_controllables.erase (i);
			break;
		}
	}

	delete dptr;
}

void
GenericMidiControlProtocol::check_used_event (int pos, int control_number)
{
	Glib::Threads::Mutex::Lock lm2 (controllables_lock);

	MIDI::channel_t channel = (pos & 0xf);
	MIDI::byte value = control_number;

	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("checking for used event: Channel: %1 Controller: %2 value: %3\n", (int) channel, (pos & 0xf0), (int) value));

	// Remove any old binding for this midi channel/type/value pair
	for (MIDIControllables::iterator iter = controllables.begin(); iter != controllables.end();) {
		MIDIControllable* existingBinding = (*iter);
		if ( (existingBinding->get_control_type() & 0xf0 ) == (pos & 0xf0) && (existingBinding->get_control_channel() & 0xf ) == channel ) {
			if ( ((int) existingBinding->get_control_additional() == (int) value) || ((pos & 0xf0) == MIDI::pitchbend)) {
				DEBUG_TRACE (DEBUG::GenericMidi, "checking: found match, delete old binding.\n");
				delete existingBinding;
				iter = controllables.erase (iter);
			} else {
				++iter;
			}
		} else {
			++iter;
		}
	}

	for (MIDIFunctions::iterator iter = functions.begin(); iter != functions.end();) {
		MIDIFunction* existingBinding = (*iter);
		if ( (existingBinding->get_control_type() & 0xf0 ) == (pos & 0xf0) && (existingBinding->get_control_channel() & 0xf ) == channel ) {
			if ( ((int) existingBinding->get_control_additional() == (int) value) || ((pos & 0xf0) == MIDI::pitchbend)) {
				DEBUG_TRACE (DEBUG::GenericMidi, "checking: found match, delete old binding.\n");
				delete existingBinding;
				iter = functions.erase (iter);
			} else {
				++iter;
			}
		} else {
			++iter;
		}
	}

	for (MIDIActions::iterator iter = actions.begin(); iter != actions.end();) {
		MIDIAction* existingBinding = (*iter);
		if ( (existingBinding->get_control_type() & 0xf0 ) == (pos & 0xf0) && (existingBinding->get_control_channel() & 0xf ) == channel ) {
			if ( ((int) existingBinding->get_control_additional() == (int) value) || ((pos & 0xf0) == MIDI::pitchbend)) {
				DEBUG_TRACE (DEBUG::GenericMidi, "checking: found match, delete old binding.\n");
				delete existingBinding;
				iter = actions.erase (iter);
			} else {
				++iter;
			}
		} else {
			++iter;
		}
	}

}

XMLNode&
GenericMidiControlProtocol::get_state ()
{
	XMLNode& node (ControlProtocol::get_state());


	XMLNode* child;

	child = new XMLNode (X_("Input"));
	child->add_child_nocopy (boost::shared_ptr<ARDOUR::Port>(_input_port)->get_state());
	node.add_child_nocopy (*child);

	child = new XMLNode (X_("Output"));
	child->add_child_nocopy (boost::shared_ptr<ARDOUR::Port>(_output_port)->get_state());
	node.add_child_nocopy (*child);

	node.set_property (X_("feedback-interval"), _feedback_interval);
	node.set_property (X_("threshold"), _threshold);
	node.set_property (X_("motorized"), _motorised);

	if (!_current_binding.empty()) {
		node.set_property ("binding", _current_binding);
	}

	XMLNode* children = new XMLNode (X_("Controls"));

	node.add_child_nocopy (*children);

	Glib::Threads::Mutex::Lock lm2 (controllables_lock);
	for (MIDIControllables::iterator i = controllables.begin(); i != controllables.end(); ++i) {

		/* we don't care about bindings that come from a bindings map, because
		   they will all be reset/recreated when we load the relevant bindings
		   file.
		*/

		if ((*i)->get_controllable() && (*i)->learned()) {
			children->add_child_nocopy ((*i)->get_state());
		}
	}

	return node;
}

int
GenericMidiControlProtocol::set_state (const XMLNode& node, int version)
{
	XMLNodeList nlist;
	XMLNodeConstIterator niter;
	XMLNode const* child;

	if (ControlProtocol::set_state (node, version)) {
		return -1;
	}

	if ((child = node.child (X_("Input"))) != 0) {
		XMLNode* portnode = child->child (Port::state_node_name.c_str());
		if (portnode) {
			portnode->remove_property ("name");
			boost::shared_ptr<ARDOUR::Port>(_input_port)->set_state (*portnode, version);
		}
	}

	if ((child = node.child (X_("Output"))) != 0) {
		XMLNode* portnode = child->child (Port::state_node_name.c_str());
		if (portnode) {
			portnode->remove_property ("name");
			boost::shared_ptr<ARDOUR::Port>(_output_port)->set_state (*portnode, version);
		}
	}

	if (!node.get_property ("feedback-interval", _feedback_interval)) {
		_feedback_interval = 10000;
	}

	if (!node.get_property ("threshold", _threshold)) {
		_threshold = 10;
	}

	if (!node.get_property ("motorized", _motorised)) {
		_motorised = false;
	}

	boost::shared_ptr<Controllable> c;

	{
		Glib::Threads::Mutex::Lock lm (pending_lock);
		for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ++i) {
			(*i)->connection.disconnect();
			if ((*i)->own_mc) {
				delete (*i)->mc;
			}
			delete *i;
		}
		pending_controllables.clear ();
	}

	std::string str;
	// midi map has to be loaded first so learned binding can go on top
	if (node.get_property ("binding", str)) {
		for (list<MapInfo>::iterator x = map_info.begin(); x != map_info.end(); ++x) {
			if (str == (*x).name) {
				load_bindings ((*x).path);
				break;
			}
		}
	}

	/* Load up specific bindings from the
	 * <Controls><MidiControllable>...</MidiControllable><Controls> section
	 */

	bool load_dynamic_bindings = false;
	node.get_property ("session-state", load_dynamic_bindings);

	if (load_dynamic_bindings) {
		Glib::Threads::Mutex::Lock lm2 (controllables_lock);
		XMLNode* controls_node = node.child (X_("Controls"));

		if (controls_node) {

			nlist = controls_node->children();

			if (!nlist.empty()) {

				for (niter = nlist.begin(); niter != nlist.end(); ++niter) {

					PBD::ID id;

					if ((*niter)->get_property ("id", id)) {

						DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("Relearned binding for session: Control ID: %1\n", id.to_s()));
						boost::shared_ptr<PBD::Controllable> c = Controllable::by_id (id);

						if (c) {
							MIDIControllable* mc = new MIDIControllable (this, *_input_port->parser(), c, false);

							if (mc->set_state (**niter, version) == 0) {
								controllables.push_back (mc);
							} else {
								warning << string_compose ("Generic MIDI control: Failed to set state for Control ID: %1\n", id.to_s());
								delete mc;
							}

						} else {
							warning << string_compose (
								_("Generic MIDI control: controllable %1 not found in session (ignored)"),
								id.to_s()) << endmsg;
						}
					}
				}
			}
		}
	}

	return 0;
}

int
GenericMidiControlProtocol::set_feedback (bool yn)
{
	do_feedback = yn;
	last_feedback_time = 0;
	return 0;
}

bool
GenericMidiControlProtocol::get_feedback () const
{
	return do_feedback;
}

int
GenericMidiControlProtocol::load_bindings (const string& xmlpath)
{
	DEBUG_TRACE (DEBUG::GenericMidi, "Load bindings: Reading midi map\n");
	XMLTree state_tree;

	if (!state_tree.read (xmlpath.c_str())) {
		error << string_compose(_("Could not understand MIDI bindings file %1"), xmlpath) << endmsg;
		return -1;
	}

	XMLNode* root = state_tree.root();

	if (root->name() != X_("ArdourMIDIBindings")) {
		error << string_compose (_("MIDI Bindings file %1 is not really a MIDI bindings file"), xmlpath) << endmsg;
		return -1;
	}

	const XMLProperty* prop;

	if ((prop = root->property ("version")) == 0) {
		return -1;
	}

	const XMLNodeList& children (root->children());
	XMLNodeConstIterator citer;

	MIDIControllable* mc;

	drop_all ();

	DEBUG_TRACE (DEBUG::GenericMidi, "Loading bindings\n");
	for (citer = children.begin(); citer != children.end(); ++citer) {

		if ((*citer)->name() == "DeviceInfo") {

			if ((*citer)->get_property ("bank-size", _bank_size)) {
				_current_bank = 0;
			}

			if (!(*citer)->get_property ("motorized", _motorised)) {
				_motorised = false;
			}

			if (!(*citer)->get_property ("threshold", _threshold)) {
				_threshold = 10;
			}
		}

		if ((*citer)->name() == "Binding") {
			const XMLNode* child = *citer;

			if (child->property ("uri")) {
				/* controllable */

				Glib::Threads::Mutex::Lock lm2 (controllables_lock);
				if ((mc = create_binding (*child)) != 0) {
					controllables.push_back (mc);
				}

			} else if (child->property ("function")) {

				/* function */
				MIDIFunction* mf;

				if ((mf = create_function (*child)) != 0) {
					functions.push_back (mf);
				}

			} else if (child->property ("action")) {
				MIDIAction* ma;

				if ((ma = create_action (*child)) != 0) {
					actions.push_back (ma);
				}
			}
		}
	}

	if ((prop = root->property ("name")) != 0) {
		_current_binding = prop->value ();
	}

	reset_controllables ();

	return 0;
}

MIDIControllable*
GenericMidiControlProtocol::create_binding (const XMLNode& node)
{
	const XMLProperty* prop;
	MIDI::byte detail;
	MIDI::channel_t channel;
	string uri;
	MIDI::eventType ev;
	int intval;
	bool momentary;
	MIDIControllable::CtlType ctltype;
	MIDIControllable::Encoder encoder = MIDIControllable::No_enc;
	bool rpn_value = false;
	bool nrpn_value = false;
	bool rpn_change = false;
	bool nrpn_change = false;

	if ((prop = node.property (X_("ctl"))) != 0) {
		ctltype = MIDIControllable::Ctl_Momentary;
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("ctl-toggle"))) !=0) {
		ctltype = MIDIControllable::Ctl_Toggle;
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("ctl-dial"))) !=0) {
		ctltype = MIDIControllable::Ctl_Dial;
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("note"))) != 0) {
		ev = MIDI::on;
	} else if ((prop = node.property (X_("pgm"))) != 0) {
		ev = MIDI::program;
	} else if ((prop = node.property (X_("pb"))) != 0) {
		ev = MIDI::pitchbend;
	} else if ((prop = node.property (X_("enc-l"))) != 0) {
		encoder = MIDIControllable::Enc_L;
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("enc-r"))) != 0) {
		encoder = MIDIControllable::Enc_R;
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("enc-2"))) != 0) {
		encoder = MIDIControllable::Enc_2;
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("enc-b"))) != 0) {
		encoder = MIDIControllable::Enc_B;
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("rpn"))) != 0) {
		rpn_value = true;
	} else if ((prop = node.property (X_("nrpn"))) != 0) {
		nrpn_value = true;
	} else if ((prop = node.property (X_("rpn-delta"))) != 0) {
		rpn_change = true;
	} else if ((prop = node.property (X_("nrpn-delta"))) != 0) {
		nrpn_change = true;
	} else {
		return 0;
	}

	if (sscanf (prop->value().c_str(), "%d", &intval) != 1) {
		return 0;
	}

	detail = (MIDI::byte) intval;

	if ((prop = node.property (X_("channel"))) == 0) {
		return 0;
	}

	if (sscanf (prop->value().c_str(), "%d", &intval) != 1) {
		return 0;
	}
	channel = (MIDI::channel_t) intval;
	/* adjust channel to zero-based counting */
	if (channel > 0) {
		channel -= 1;
	}

	if ((prop = node.property (X_("momentary"))) != 0) {
		momentary = string_to<bool> (prop->value());
	} else {
		momentary = false;
	}

	prop = node.property (X_("uri"));
	uri = prop->value();

	MIDIControllable* mc = new MIDIControllable (this, *_input_port->parser(), momentary);

	if (mc->init (uri)) {
		delete mc;
		return 0;
	}

	if (rpn_value) {
		mc->bind_rpn_value (channel, detail);
	} else if (nrpn_value) {
		mc->bind_nrpn_value (channel, detail);
	} else if (rpn_change) {
		mc->bind_rpn_change (channel, detail);
	} else if (nrpn_change) {
		mc->bind_nrpn_change (channel, detail);
	} else {
		mc->set_ctltype (ctltype);
		mc->set_encoder (encoder);
		mc->bind_midi (channel, ev, detail);
	}

	return mc;
}

void
GenericMidiControlProtocol::reset_controllables ()
{
	Glib::Threads::Mutex::Lock lm2 (controllables_lock);

	for (MIDIControllables::iterator iter = controllables.begin(); iter != controllables.end(); ) {
		MIDIControllable* existingBinding = (*iter);
		MIDIControllables::iterator next = iter;
		++next;

		if (!existingBinding->learned()) {

			/* its entirely possible that the session doesn't have
			 * the specified controllable (e.g. it has too few
			 * tracks). if we find this to be the case, we just leave
			 * the binding around, unbound, and it will do "late
			 * binding" (or "lazy binding") if/when any data arrives.
			 */

			existingBinding->lookup_controllable ();
		}

		iter = next;
	}
}

boost::shared_ptr<Controllable>
GenericMidiControlProtocol::lookup_controllable (const string & str) const
{
	boost::shared_ptr<Controllable> c;

	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("lookup controllable from \"%1\"\n", str));

	if (!session) {
		DEBUG_TRACE (DEBUG::GenericMidi, "no session\n");
		return c;
	}

	/* step 1: split string apart */

	string::size_type first_space = str.find_first_of (" ");

	if (first_space == string::npos) {
		return c;
	}

	string front = str.substr (0, first_space);
	vector<string> path;
	split (front, path, '/');

	if (path.size() < 2) {
		return c;
	}

	string back = str.substr (first_space);
	vector<string> rest;
	split (back, rest, ' ');

	if (rest.empty()) {
		return c;
	}

	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("parsed into path of %1, rest of %1\n", path.size(), rest.size()));

	/* Step 2: analyse parts of the string to figure out what type of
	 * Stripable we're looking for
	 */

	enum Type {
		Selection,
		PresentationOrder,
		Named,
	};
	Type type = Named;
	int id = 1;
	string name;

	static regex_t compiled_pattern;
	static bool compiled = false;

	if (!compiled) {
		const char * const pattern = "^[BS]?[0-9]+";
		/* this pattern compilation is not going to fail */
		regcomp (&compiled_pattern, pattern, REG_EXTENDED|REG_NOSUB);
		/* leak compiled pattern */
		compiled = true;
	}

	/* Step 3: identify what "rest" looks like - name, or simple nueric, or
	 * banked/selection specifier
	 */

	bool matched = (regexec (&compiled_pattern, rest[0].c_str(), 0, 0, 0) == 0);

	if (matched) {
		bool banked = false;

		if (rest[0][0] == 'B') {
			banked = true;
			/* already matched digits, so we know atoi() will succeed */
			id = atoi (rest[0].substr (1));
			type = PresentationOrder;
		} else if (rest[0][0] == 'S') {
			/* already matched digits, so we know atoi() will succeed */
			id = atoi (rest[0].substr (1));
			type = Selection;
		} else if (isdigit (rest[0][0])) {
			/* already matched digits, so we know atoi() will succeed */
			id = atoi (rest[0]);
			type = PresentationOrder;
		} else {
			return c;
		}

		id -= 1; /* order is zero-based, but maps use 1-based */

		if (banked) {
			id += _current_bank * _bank_size;
		}

	} else {

		type = Named;
		name = rest[0];
	}

	/* step 4: find the reference Stripable */

	boost::shared_ptr<Stripable> s;

	if (path[0] == X_("route") || path[0] == X_("rid")) {

		std::string name;

		switch (type) {
		case PresentationOrder:
			s = session->get_remote_nth_stripable (id, PresentationInfo::Route);
			break;
		case Named:
			/* name */
			name = rest[0];

			if (name == "Master" || name == X_("master")) {
				s = session->master_out();
			} else if (name == X_("control") || name == X_("listen") || name == X_("monitor") || name == "Monitor") {
				s = session->monitor_out();
			} else if (name == X_("auditioner")) {
				s = session->the_auditioner();
			} else {
				s = session->route_by_name (name);
			}
			break;

		case Selection:
			s = session->route_by_selected_count (id);
			break;
		}

	} else if (path[0] == X_("vca")) {

		s = session->get_remote_nth_stripable (id, PresentationInfo::VCA);

	} else if (path[0] == X_("bus")) {

		switch (type) {
		case Named:
			s = session->route_by_name (name);
			break;
		default:
			s = session->get_remote_nth_stripable (id, PresentationInfo::Bus);
		}

	} else if (path[0] == X_("track")) {

		switch (type) {
		case Named:
			s = session->route_by_name (name);
			break;
		default:
			s = session->get_remote_nth_stripable (id, PresentationInfo::Track);
		}
	}

	if (!s) {
		DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("no stripable found for \"%1\"\n", str));
		return c;
	}

	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("found stripable %1\n", s->name()));

	/* step 5: find the referenced controllable for that stripable.
	 *
	 * Some controls exist only for Route, so we need that too
	 */

	boost::shared_ptr<Route> r = boost::dynamic_pointer_cast<Route> (s);

	if (path[1] == X_("gain")) {
		c = s->gain_control();
	} else if (path[1] == X_("trim")) {
		c = s->trim_control ();
	} else if (path[1] == X_("solo")) {
		c = s->solo_control();
	} else if (path[1] == X_("mute")) {
		c = s->mute_control();
	} else if (path[1] == X_("recenable")) {
		c = s->rec_enable_control ();
	} else if (path[1] == X_("panwidth")) {
		c = s->pan_width_control ();
	} else if (path[1] == X_("pandirection") || path[1] == X_("balance")) {
		c = s->pan_azimuth_control ();
	} else if (path[1] == X_("plugin")) {

		/* /route/plugin/parameter */

		if (path.size() == 3 && rest.size() == 3) {
			if (path[2] == X_("parameter")) {

				int plugin = atoi (rest[1]);
				int parameter_index = atoi (rest[2]);

				/* revert to zero based counting */
				if (plugin > 0) {
					--plugin;
				}
				if (parameter_index > 0) {
					--parameter_index;
				}

				if (r) {
					boost::shared_ptr<Processor> proc = r->nth_plugin (plugin);

					if (proc) {
						boost::shared_ptr<PluginInsert> p = boost::dynamic_pointer_cast<PluginInsert> (proc);
						if (p) {
							uint32_t param;
							bool ok;
							param = p->plugin()->nth_parameter (parameter_index, ok);
							if (ok) {
								c = boost::dynamic_pointer_cast<Controllable> (proc->control (Evoral::Parameter (PluginAutomation, 0, param)));
							}
						}
					}
				}
			}
		}

	} else if (path[1] == X_("send")) {

		if (path.size() == 3 && rest.size() == 2) {
			if (path[2] == X_("gain")) {
				uint32_t send = atoi (rest[1]);
				if (send > 0) {
					--send;
				}
				c = s->send_level_controllable (send);
			} else if (path[2] == X_("direction")) {
				/* XXX not implemented yet */

			} else if (path[2] == X_("enable")) {
				/* XXX not implemented yet */
			}
		}

	} else if (path[1] == X_("eq")) {

		/* /route/eq/enable */
		/* /route/eq/gain/<band> */
		/* /route/eq/freq/<band> */
		/* /route/eq/q/<band> */
		/* /route/eq/shape/<band> */

		if (path.size() == 3) {

			if (path[2] == X_("enable")) {
				c = s->eq_enable_controllable ();
			}

		} else if (path.size() == 4) {

			int band = atoi (path[3]); /* band number */

			if (path[2] == X_("gain")) {
				c = s->eq_gain_controllable (band);
			} else if (path[2] == X_("freq")) {
				c = s->eq_freq_controllable (band);
			} else if (path[2] == X_("q")) {
				c = s->eq_q_controllable (band);
			} else if (path[2] == X_("shape")) {
				c = s->eq_shape_controllable (band);
			}
		}

	} else if (path[1] == X_("filter")) {

		/* /route/filter/hi/freq */

		if (path.size() == 4) {

			int filter;

			if (path[2] == X_("hi")) {
				filter = 1; /* high pass filter */
			} else {
				filter = 0; /* low pass filter */
			}

			if (path[3] == X_("enable")) {
				c = s->filter_enable_controllable (filter);
			} else if (path[3] == X_("freq")) {
				c = s->filter_freq_controllable (filter);
			} else if (path[3] == X_("slope")) {
				c = s->filter_slope_controllable (filter);
			}

		}

	} else if (path[1] == X_("compressor")) {

		if (path.size() == 3) {
			if (path[2] == X_("enable")) {
				c = s->comp_enable_controllable ();
			} else if (path[2] == X_("threshold")) {
				c = s->comp_threshold_controllable ();
			} else if (path[2] == X_("mode")) {
				c = s->comp_mode_controllable ();
			} else if (path[2] == X_("speed")) {
				c = s->comp_speed_controllable ();
			} else if (path[2] == X_("makeup")) {
				c = s->comp_makeup_controllable ();
			}
		}
	}

	if (c) {
		DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("found controllable \"%1\"\n", c->name()));
	} else {
		DEBUG_TRACE (DEBUG::GenericMidi, "no controllable found\n");
	}

	return c;
}

MIDIFunction*
GenericMidiControlProtocol::create_function (const XMLNode& node)
{
	const XMLProperty* prop;
	int intval;
	MIDI::byte detail = 0;
	MIDI::channel_t channel = 0;
	string uri;
	MIDI::eventType ev;
	MIDI::byte* data = 0;
	uint32_t data_size = 0;
	string argument;

	if ((prop = node.property (X_("ctl"))) != 0) {
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("note"))) != 0) {
		ev = MIDI::on;
	} else if ((prop = node.property (X_("pgm"))) != 0) {
		ev = MIDI::program;
	} else if ((prop = node.property (X_("sysex"))) != 0 || (prop = node.property (X_("msg"))) != 0) {

		if (prop->name() == X_("sysex")) {
			ev = MIDI::sysex;
		} else {
			ev = MIDI::any;
		}

		int val;
		uint32_t cnt;

		{
			cnt = 0;
			stringstream ss (prop->value());
			ss << hex;

			while (ss >> val) {
				cnt++;
			}
		}

		if (cnt == 0) {
			return 0;
		}

		data = new MIDI::byte[cnt];
		data_size = cnt;

		{
			stringstream ss (prop->value());
			ss << hex;
			cnt = 0;

			while (ss >> val) {
				data[cnt++] = (MIDI::byte) val;
			}
		}

	} else {
		warning << "Binding ignored - unknown type" << endmsg;
		return 0;
	}

	if (data_size == 0) {
		if (sscanf (prop->value().c_str(), "%d", &intval) != 1) {
			return 0;
		}

		detail = (MIDI::byte) intval;

		if ((prop = node.property (X_("channel"))) == 0) {
			return 0;
		}

		if (sscanf (prop->value().c_str(), "%d", &intval) != 1) {
			return 0;
		}
		channel = (MIDI::channel_t) intval;
		/* adjust channel to zero-based counting */
		if (channel > 0) {
			channel -= 1;
		}
	}

	if ((prop = node.property (X_("arg"))) != 0 || (prop = node.property (X_("argument"))) != 0 || (prop = node.property (X_("arguments"))) != 0) {
		argument = prop->value ();
	}

	prop = node.property (X_("function"));

	MIDIFunction* mf = new MIDIFunction (*_input_port->parser());

	if (mf->setup (*this, prop->value(), argument, data, data_size)) {
		delete mf;
		return 0;
	}

	mf->bind_midi (channel, ev, detail);

	return mf;
}

MIDIAction*
GenericMidiControlProtocol::create_action (const XMLNode& node)
{
	const XMLProperty* prop;
	int intval;
	MIDI::byte detail = 0;
	MIDI::channel_t channel = 0;
	string uri;
	MIDI::eventType ev;
	MIDI::byte* data = 0;
	uint32_t data_size = 0;

	if ((prop = node.property (X_("ctl"))) != 0) {
		ev = MIDI::controller;
	} else if ((prop = node.property (X_("note"))) != 0) {
		ev = MIDI::on;
	} else if ((prop = node.property (X_("pgm"))) != 0) {
		ev = MIDI::program;
	} else if ((prop = node.property (X_("sysex"))) != 0 || (prop = node.property (X_("msg"))) != 0) {

		if (prop->name() == X_("sysex")) {
			ev = MIDI::sysex;
		} else {
			ev = MIDI::any;
		}

		int val;
		uint32_t cnt;

		{
			cnt = 0;
			stringstream ss (prop->value());
			ss << hex;

			while (ss >> val) {
				cnt++;
			}
		}

		if (cnt == 0) {
			return 0;
		}

		data = new MIDI::byte[cnt];
		data_size = cnt;

		{
			stringstream ss (prop->value());
			ss << hex;
			cnt = 0;

			while (ss >> val) {
				data[cnt++] = (MIDI::byte) val;
			}
		}

	} else {
		warning << "Binding ignored - unknown type" << endmsg;
		return 0;
	}

	if (data_size == 0) {
		if (sscanf (prop->value().c_str(), "%d", &intval) != 1) {
			return 0;
		}

		detail = (MIDI::byte) intval;

		if ((prop = node.property (X_("channel"))) == 0) {
			return 0;
		}

		if (sscanf (prop->value().c_str(), "%d", &intval) != 1) {
			return 0;
		}
		channel = (MIDI::channel_t) intval;
		/* adjust channel to zero-based counting */
		if (channel > 0) {
			channel -= 1;
		}
	}

	prop = node.property (X_("action"));

	MIDIAction* ma = new MIDIAction (*_input_port->parser());

	if (ma->init (*this, prop->value(), data, data_size)) {
		delete ma;
		return 0;
	}

	ma->bind_midi (channel, ev, detail);

	return ma;
}

void
GenericMidiControlProtocol::set_current_bank (uint32_t b)
{
	_current_bank = b;
	reset_controllables ();
}

void
GenericMidiControlProtocol::next_bank ()
{
	_current_bank++;
	reset_controllables ();
}

void
GenericMidiControlProtocol::prev_bank()
{
	if (_current_bank) {
		_current_bank--;
		reset_controllables ();
	}
}

void
GenericMidiControlProtocol::set_motorised (bool m)
{
	_motorised = m;
}

void
GenericMidiControlProtocol::set_threshold (int t)
{
	_threshold = t;
}

bool
GenericMidiControlProtocol::connection_handler (boost::weak_ptr<ARDOUR::Port>, std::string name1, boost::weak_ptr<ARDOUR::Port>, std::string name2, bool yn)
{
	bool input_was_connected = (connection_state & InputConnected);

	if (!_input_port || !_output_port) {
		return false;
	}

	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("connection change: %1 and %2 connected ? %3\n", name1, name2, yn));

	string ni = ARDOUR::AudioEngine::instance()->make_port_name_non_relative (boost::shared_ptr<ARDOUR::Port>(_input_port)->name());
	string no = ARDOUR::AudioEngine::instance()->make_port_name_non_relative (boost::shared_ptr<ARDOUR::Port>(_output_port)->name());

	if (ni == name1 || ni == name2) {
		if (yn) {
			connection_state |= InputConnected;
		} else {
			connection_state &= ~InputConnected;
		}
	} else if (no == name1 || no == name2) {
		if (yn) {
			connection_state |= OutputConnected;
		} else {
			connection_state &= ~OutputConnected;
		}
	} else {
		/* not our ports */
		return false;
	}

	if (connection_state & InputConnected) {
		if (!input_was_connected) {
			start_midi_handling ();
		}
	} else {
		if (input_was_connected) {
			stop_midi_handling ();
		}
	}

	ConnectionChange (); /* emit signal for our GUI */

	return true; /* connection status changed */
}

boost::shared_ptr<Port>
GenericMidiControlProtocol::output_port() const
{
	return _output_port;
}

boost::shared_ptr<Port>
GenericMidiControlProtocol::input_port() const
{
	return _input_port;
}

void
GenericMidiControlProtocol::maybe_start_touch (boost::shared_ptr<Controllable> controllable)
{
	boost::shared_ptr<AutomationControl> actl = boost::dynamic_pointer_cast<AutomationControl> (controllable);
	if (actl) {
		actl->start_touch (timepos_t (session->audible_sample ()));
	}
}


void
GenericMidiControlProtocol::start_midi_handling ()
{
	/* This connection means that whenever data is ready from the input
	 * port, the relevant thread will invoke our ::midi_input_handler()
	 * method, which will read the data, and invoke the parser.
	 */

	_input_port->xthread().set_receive_handler (sigc::bind (sigc::mem_fun (this, &GenericMidiControlProtocol::midi_input_handler), boost::weak_ptr<AsyncMIDIPort> (_input_port)));
	_input_port->xthread().attach (main_loop()->get_context());
}

void
GenericMidiControlProtocol::stop_midi_handling ()
{
	midi_connections.drop_connections ();

	/* Note: the input handler is still active at this point, but we're no
	 * longer connected to any of the parser signals
	 */
}

bool
GenericMidiControlProtocol::midi_input_handler (Glib::IOCondition ioc, boost::weak_ptr<ARDOUR::AsyncMIDIPort> wport)
{
	boost::shared_ptr<AsyncMIDIPort> port (wport.lock());

	if (!port) {
		return false;
	}

	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("something happend on  %1\n", boost::shared_ptr<MIDI::Port>(port)->name()));

	if (ioc & ~IO_IN) {
		return false;
	}

	if (ioc & IO_IN) {

		port->clear ();
		DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("data available on %1\n", boost::shared_ptr<MIDI::Port>(port)->name()));
		samplepos_t now = session->engine().sample_time();
		port->parse (now);
	}

	return true;
}