/*
 * Copyright (C) 2006-2007 John Anderson
 * Copyright (C) 2008-2016 Paul Davis <paul@linuxaudiosystems.com>
 * Copyright (C) 2008 Doug McLain <doug@nostar.net>
 * Copyright (C) 2010-2012 Carl Hetherington <carl@carlh.net>
 * Copyright (C) 2015-2016 Len Ovens <len@ovenwerks.net>
 * Copyright (C) 2015-2016 Robin Gareus <robin@gareus.org>
 * Copyright (C) 2016-2018 Ben Loftis <ben@harrisonconsoles.com>
 *
 * 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 <sstream>
#include <iomanip>
#include <iostream>
#include <cstdio>
#include <cmath>

#include <glibmm/convert.h>

#include "pbd/debug.h"

#include "midi++/port.h"

#include "ardour/audioengine.h"
#include "ardour/automation_control.h"
#include "ardour/chan_count.h"
#include "ardour/debug.h"
#include "ardour/route.h"
#include "ardour/meter.h"
#include "ardour/panner.h"
#include "ardour/panner_shell.h"
#include "ardour/profile.h"
#include "ardour/rc_configuration.h"
#include "ardour/session.h"
#include "ardour/types.h"
#include "ardour/utils.h"

#include <gtkmm2ext/gui_thread.h>

#include "control_group.h"
#include "surface_port.h"
#include "surface.h"
#include "strip.h"
#include "mackie_control_protocol.h"
#include "jog_wheel.h"

#include "strip.h"
#include "button.h"
#include "led.h"
#include "pot.h"
#include "fader.h"
#include "jog.h"
#include "meter.h"

#include "pbd/i18n.h"

#ifdef PLATFORM_WINDOWS
#define random() rand()
#endif

using namespace std;
using namespace PBD;
using ARDOUR::Stripable;
using ARDOUR::Panner;
using ARDOUR::Profile;
using ARDOUR::AutomationControl;
using ARDOUR::ChanCount;
using namespace ArdourSurface;
using namespace Mackie;

#define ui_context() MackieControlProtocol::instance() /* a UICallback-derived object that specifies the event loop for signal handling */

// The MCU sysex header.4th byte Will be overwritten
// when we get an incoming sysex that identifies
// the device type
static MidiByteArray mackie_sysex_hdr  (5, MIDI::sysex, 0x0, 0x0, 0x66, 0x14);

// The MCU extender sysex header.4th byte Will be overwritten
// when we get an incoming sysex that identifies
// the device type
static MidiByteArray mackie_sysex_hdr_xt  (5, MIDI::sysex, 0x0, 0x0, 0x66, 0x15);

//QCON
// The MCU sysex header for QCon Control surface
static MidiByteArray mackie_sysex_hdr_qcon  (5, MIDI::sysex, 0x0, 0x0, 0x66, 0x14);

// The MCU sysex header for QCon Control - extender
// The extender differs from Mackie by 4th bit - it's same like for main control surface (for display)
static MidiByteArray mackie_sysex_hdr_xt_qcon  (5, MIDI::sysex, 0x0, 0x0, 0x66, 0x14);


static MidiByteArray empty_midi_byte_array;

Surface::Surface (MackieControlProtocol& mcp, const std::string& device_name, uint32_t number, surface_type_t stype)
	: _mcp (mcp)
	, _stype (stype)
	, _number (number)
	, _name (device_name)
	, _active (false)
	, _connected (false)
	, _jog_wheel (0)
	, _master_fader (0)
	, _last_master_gain_written (-0.0f)
	, _has_master_display (false)
	, _has_master_meter (false)
	, connection_state (0)
	, is_qcon (false)
	, input_source (0)
{
	DEBUG_TRACE (DEBUG::MackieControl, "Surface::Surface init\n");

	try {
		_port = new SurfacePort (*this);
	} catch (...) {
		throw failed_constructor ();
	}

	//Store Qcon flag
	is_qcon = mcp.device_info().is_qcon();

	/* only the first Surface object has global controls */
	/* lets use master_position instead */
	uint32_t mp = _mcp.device_info().master_position();
	if (_number == mp) {
		DEBUG_TRACE (DEBUG::MackieControl, "Surface matches MasterPosition. Might have global controls.\n");

		if ( is_qcon ) {
			_has_master_display = (mcp.device_info().has_master_fader() && mcp.device_info().has_qcon_second_lcd());
			_has_master_meter = mcp.device_info().has_qcon_master_meters();
		}

		if (_mcp.device_info().has_global_controls()) {
			init_controls ();
			DEBUG_TRACE (DEBUG::MackieControl, "init_controls done\n");
		}

		if (_mcp.device_info().has_master_fader()) {
			setup_master ();
			DEBUG_TRACE (DEBUG::MackieControl, "setup_master done\n");
		}
	}

	uint32_t n = _mcp.device_info().strip_cnt();

	if (n) {
		init_strips (n);
		DEBUG_TRACE (DEBUG::MackieControl, "init_strips done\n");
	}

	if (_mcp.device_info().uses_ipmidi()) {
		/* ipMIDI port already exists, we can just assume that we're
		 * connected.
		 *
		 * If the user still hasn't connected the ipMIDI surface and/or
		 * turned it on, then they have to press "Discover Mackie
		 * Devices" in the GUI at the right time.
		 */

		connection_state |= (InputConnected|OutputConnected);
		connected ();
	}

	connect_to_signals ();

	DEBUG_TRACE (DEBUG::MackieControl, "Surface::Surface done\n");
}

Surface::~Surface ()
{
	DEBUG_TRACE (DEBUG::MackieControl, "Surface::~Surface init\n");

	if (input_source) {
		g_source_destroy (input_source);
		input_source = 0;
	}

	// delete groups (strips)
	for (Groups::iterator it = groups.begin(); it != groups.end(); ++it) {
		delete it->second;
	}

	// delete controls (global buttons, master fader etc)
	for (Controls::iterator it = controls.begin(); it != controls.end(); ++it) {
		delete *it;
	}

	delete _jog_wheel;
	delete _port;
	// the ports take time to release and we may be rebuilding right away
	// in the case of changing devices.
	g_usleep (10000);
	DEBUG_TRACE (DEBUG::MackieControl, "Surface::~Surface done\n");
}

bool
Surface::connection_handler (boost::weak_ptr<ARDOUR::Port>, std::string name1, boost::weak_ptr<ARDOUR::Port>, std::string name2, bool yn)
{
	if (!_port) {
		return false;
	}

	string ni = ARDOUR::AudioEngine::instance()->make_port_name_non_relative (_port->input_name());
	string no = ARDOUR::AudioEngine::instance()->make_port_name_non_relative (_port->output_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|OutputConnected)) == (InputConnected|OutputConnected)) {

		/* this will send a device query message, which should
		   result in a response that will kick off device type
		   discovery and activation of the surface(s).

		   The intended order of events is:

		   - each surface sends a device query message
		   - devices respond with either MCP or LCP response (sysex in both
		   cases)
		   - sysex message causes Surface::turn_it_on() which tells the
		   MCP object that the surface is ready, and sets up strip
		   displays and binds faders and buttons for that surface

		   In the case of LCP, where this is a handshake process that could
		   fail, the response process to the initial sysex after a device query
		   will mark the surface inactive, which won't shut anything down
		   but will stop any writes to the device.

		   Note: there are no known cases of the handshake process failing.

		   We actually can't initiate this in this callback, so we have
		   to queue it with the MCP event loop.
		*/

		/* XXX this is a horrible hack. Without a short sleep here,
		   something prevents the device wakeup messages from being
		   sent and/or the responses from being received.
		*/

		g_usleep (100000);
		connected ();

	} else {
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Surface %1 disconnected (input or output or both)\n", _name));
		_active = false;
	}

	return true; /* connection status changed */
}

XMLNode&
Surface::get_state() const
{
	XMLNode* node = new XMLNode (X_("Surface"));
	node->set_property (X_("name"), _name);
	node->add_child_nocopy (_port->get_state());
	return *node;
}

int
Surface::set_state (const XMLNode& node, int version)
{
	/* Look for a node named after the device we're part of */

	XMLNodeList const& children = node.children();
	XMLNode* mynode = 0;

	for (XMLNodeList::const_iterator c = children.begin(); c != children.end(); ++c) {
		std::string name;
		if ((*c)->get_property (X_("name"), name) && name == _name) {
			mynode = *c;
			break;
		}
	}

	if (!mynode) {
		return 0;
	}

	XMLNode* portnode = mynode->child (X_("Port"));
	if (portnode) {
		if (_port->set_state (*portnode, version)) {
			return -1;
		}
	}

	return 0;
}

const MidiByteArray&
Surface::sysex_hdr() const
{
	switch  (_stype) {
	case mcu:
		if (_mcp.device_info().is_qcon()) {
			return mackie_sysex_hdr_qcon;
		} else {
			return mackie_sysex_hdr;
		}
	case ext:
		if(_mcp.device_info().is_qcon()) {
			return mackie_sysex_hdr_xt_qcon;
		} else {
			return mackie_sysex_hdr_xt;
		}
	}
	cout << "SurfacePort::sysex_hdr _port_type not known" << endl;
	return mackie_sysex_hdr;
}

static GlobalControlDefinition mackie_global_controls[] = {
	{ "external", Pot::External, Pot::factory, "none" },
	{ "fader_touch", Led::FaderTouch, Led::factory, "master" },
	{ "timecode", Led::Timecode, Led::factory, "none" },
	{ "beats", Led::Beats, Led::factory, "none" },
	{ "solo", Led::RudeSolo, Led::factory, "none" },
	{ "relay_click", Led::RelayClick, Led::factory, "none" },
	{ "", 0, Led::factory, "" }
};

void
Surface::init_controls()
{
	Group* group;

	DEBUG_TRACE (DEBUG::MackieControl, "Surface::init_controls: creating groups\n");
	groups["assignment"] = new Group  ("assignment");
	groups["automation"] = new Group  ("automation");
	groups["bank"] = new Group  ("bank");
	groups["cursor"] = new Group  ("cursor");
	groups["display"] = new Group  ("display");
	groups["function select"] = new Group  ("function select");
	groups["global view"] = new Group ("global view");
	groups["master"] = new Group ("master");
	groups["modifiers"] = new Group  ("modifiers");
	groups["none"] = new Group  ("none");
	groups["transport"] = new Group  ("transport");
	groups["user"] = new Group  ("user");
	groups["utilities"] = new Group  ("utilities");

	DEBUG_TRACE (DEBUG::MackieControl, "Surface::init_controls: creating jog wheel\n");
	if (_mcp.device_info().has_jog_wheel()) {
		_jog_wheel = new Mackie::JogWheel (_mcp);
	}

	DEBUG_TRACE (DEBUG::MackieControl, "Surface::init_controls: creating global controls\n");
	for (uint32_t n = 0; mackie_global_controls[n].name[0]; ++n) {
		group = groups[mackie_global_controls[n].group_name];
		Control* control = mackie_global_controls[n].factory (*this, mackie_global_controls[n].id, mackie_global_controls[n].name, *group);
		controls_by_device_independent_id[mackie_global_controls[n].id] = control;
	}

	/* add global buttons */
	DEBUG_TRACE (DEBUG::MackieControl, "Surface::init_controls: adding global buttons\n");
	const map<Button::ID,GlobalButtonInfo>& global_buttons (_mcp.device_info().global_buttons());

	for (map<Button::ID,GlobalButtonInfo>::const_iterator b = global_buttons.begin(); b != global_buttons.end(); ++b){
		group = groups[b->second.group];
		controls_by_device_independent_id[b->first] = Button::factory (*this, b->first, b->second.id, b->second.label, *group);
	}
}

void
Surface::init_strips (uint32_t n)
{
	const map<Button::ID,StripButtonInfo>& strip_buttons (_mcp.device_info().strip_buttons());

	for (uint32_t i = 0; i < n; ++i) {

		char name[32];

		snprintf (name, sizeof (name), "strip_%d", (8* _number) + i);

		Strip* strip = new Strip (*this, name, i, strip_buttons);

		groups[name] = strip;
		strips.push_back (strip);
	}
}

void
Surface::master_monitor_may_have_changed ()
{
	if (_number == _mcp.device_info().master_position()) {
		setup_master ();
	}
}

bool
Surface::master_stripable_is_master_monitor ()
{
	if (_master_stripable == _mcp.get_session().monitor_out())
	{
		return true;
	}
	return false;
}

void
Surface::toggle_master_monitor ()
{
	if(master_stripable_is_master_monitor())
	{
		_master_stripable = _mcp.get_session().master_out();
	} else if (_mcp.get_session().monitor_out() != 0)
	{
		_master_stripable = _mcp.get_session().monitor_out();
	} else { return; }

	_master_fader->set_control (_master_stripable->gain_control());
	_master_stripable->gain_control()->Changed.connect (master_connection, MISSING_INVALIDATOR, boost::bind (&Surface::master_gain_changed, this), ui_context());
	_last_master_gain_written = FLT_MAX;
	master_gain_changed ();
}

void
Surface::setup_master ()
{
	if ((_master_stripable = _mcp.get_session().monitor_out()) == 0) {
		_master_stripable = _mcp.get_session().master_out();
	}

	if (!_master_stripable) {
		if (_master_fader) {
			_master_fader->set_control (boost::shared_ptr<AutomationControl>());
		}
		master_connection.disconnect ();
		return;
	}

	if (!_master_fader) {
		Groups::iterator group_it;
		Group* master_group;
		group_it = groups.find("master");
		DeviceInfo device_info = _mcp.device_info();

		if (group_it == groups.end()) {
			groups["master"] = master_group = new Group ("master");
		} else {
			master_group = group_it->second;
		}

		_master_fader = dynamic_cast<Fader*> (Fader::factory (*this, device_info.strip_cnt(), "master", *master_group));

		GlobalButtonInfo master_button = device_info.get_global_button(Button::MasterFaderTouch);
		DEBUG_RESULT_CAST (Button*, bb, dynamic_cast<Button*>, (Button::factory (
			                                                        *this,
			                                                        Button::MasterFaderTouch,
			                                                        master_button.id,
			                                                        master_button.label,
			                                                        *(group_it->second)
			                                                        )));
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("surface %1 Master Fader new button BID %2 id %3\n",
		                                                   number(), Button::MasterFaderTouch, bb->id()));
	} else {
		master_connection.disconnect ();
	}

	_master_fader->set_control (_master_stripable->gain_control());
	_master_stripable->gain_control()->Changed.connect (master_connection, MISSING_INVALIDATOR, boost::bind (&Surface::master_gain_changed, this), ui_context());
	_last_master_gain_written = FLT_MAX; /* some essentially impossible value */
	master_gain_changed ();

	if (_has_master_display) {
		_master_stripable->PropertyChanged.connect (master_connection, MISSING_INVALIDATOR, boost::bind (&Surface::master_property_changed, this, _1), ui_context());
		show_master_name();
	}
}

void
Surface::master_gain_changed ()
{
	if (!_master_fader) {
		return;
	}

	boost::shared_ptr<AutomationControl> ac = _master_fader->control();
	if (!ac) {
		return;
	}

	float normalized_position = ac->internal_to_interface (ac->get_value());
	if (normalized_position == _last_master_gain_written) {
		return;
	}

	DEBUG_TRACE (DEBUG::MackieControl, string_compose("Surface::master_gain_changed: val %1, pos %2\n", ac->get_value(), normalized_position));

	write (_master_fader->set_position (normalized_position));
	_last_master_gain_written = normalized_position;
}

void
Surface::master_property_changed (const PropertyChange& what_changed)
{
	if (what_changed.contains (ARDOUR::Properties::name)) {
		DEBUG_TRACE (DEBUG::MackieControl, "master_property_changed\n");

		string fullname = string();
		if (!_master_stripable) {
			fullname = string();
		} else {
			fullname = _master_stripable->name();
		}

		if (fullname.length() <= 6) {
			pending_display[0] = fullname;
		} else {
			pending_display[0] = PBD::short_version (fullname, 6);
		}
	}
}

void
Surface::master_meter_changed ()
{
	if (!_has_master_meter) {
		return;
	}

	if (!_master_stripable) {
		return;
	}

	ChanCount count = _master_stripable->peak_meter()->output_streams();

	for (unsigned i = 0; i < 2 && i < count.n_audio(); ++i) {
		int segment;
		float dB = _master_stripable->peak_meter()->meter_level (i, ARDOUR::MeterPeak);
		std::pair<bool,float> result = Meter::calculate_meter_over_and_deflection(dB);

		MidiByteArray msg;

		/* we can use up to 13 segments */

		segment = lrintf ((result.second/115.0) * 13.0);
		write (MidiByteArray (2, 0xd1, (i<<4) | segment));
	}
}

void
Surface::show_master_name ()
{
	string fullname = string();
	if (!_master_stripable) {
		fullname = string();
	} else {
		fullname = _master_stripable->name();
	}

	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("show_master_name: name %1\n", fullname));

	if (fullname.length() <= 6) {
		pending_display[0] = fullname;
	} else {
		pending_display[0] = PBD::short_version (fullname, 6);
	}
}

MidiByteArray
Surface::master_display (uint32_t line_number, const std::string& line)
{
	/* The second lcd on the Qcon Pro X master unit uses a 6 character label instead of 7.
	*  That allows a 9th label for the master fader and since there is a space at the end
	*  use all 6 characters for text.
	*
	*  Format: _6Char#1_6Char#2_6Char#3_6Char#4_6Char#5_6Char#6_6Char#7_6Char#8_6Char#9_
	*
	*  The _ in the format is a space that is inserted as label display seperators
	*
	*  The second LCD is an extention to the MCP with a different sys ex header.
	*/

	MidiByteArray retval;

	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("master display: line %1 = %2\n", line_number, line));

	retval <<  MidiByteArray (5, MIDI::sysex, 0x0, 0x0, 0x67, 0x15);
	// code for display
	retval << 0x13;

	// offset (0 to 0x37 first line, 0x38 to 0x6f for second line)
	retval << (49 + (line_number * 0x38));	// 9th position

	// ascii data to display. `line` is UTF-8
	string ascii = Glib::convert_with_fallback (line, "UTF-8", "ISO-8859-1", "_");
	string::size_type len = ascii.length();
	if (len > 6) {
		ascii = ascii.substr (0, 6);
		len = 5;
	}
	retval << ascii;
	// pad with " " out to N chars
	for (unsigned i = len; i < 6; ++i) {
		retval << ' ';
	}

	// Space as the last character
	retval << ' ';

	// sysex trailer
	retval << MIDI::eox;

	return retval;
}

MidiByteArray
Surface::blank_master_display (uint32_t line_number)
{
	if (line_number == 0) {
		return MidiByteArray (15, MIDI::sysex, 0x0, 0x0, 0x67, 0x15, 0x13, 0x31
                      , 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, MIDI::eox);
	}
	else {
		return MidiByteArray (15, MIDI::sysex, 0x0, 0x0, 0x67, 0x15, 0x13, 0x69
                      , 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, MIDI::eox);
	}
}

float
Surface::scaled_delta (float delta, float current_speed)
{
	/* XXX needs work before use */
	const float sign = delta < 0.0 ? -1.0 : 1.0;

	return ((sign * std::pow (delta + 1.0, 2.0)) + current_speed) / 100.0;
}

void
Surface::display_bank_start (uint32_t current_bank)
{
	if  (current_bank == 0) {
		// send Ar. to 2-char display on the master
		show_two_char_display ("Ar", "..");
	} else {
		// write the current first remote_id to the 2-char display
		show_two_char_display (current_bank);
	}
}

void
Surface::blank_jog_ring ()
{
	Control* control = controls_by_device_independent_id[Jog::ID];

	if (control) {
		Pot* pot = dynamic_cast<Pot*> (control);
		if (pot) {
			_port->write (pot->set (0.0, false, Pot::spread));
		}
	}
}

float
Surface::scrub_scaling_factor () const
{
	return 100.0;
}

void
Surface::connect_to_signals ()
{
	if (!_connected) {


		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Surface %1 connecting to signals on port %2\n",
								   number(), _port->input_port().name()));

		MIDI::Parser* p = _port->input_port().parser();

		/* Incoming sysex */
		p->sysex.connect_same_thread (*this, boost::bind (&Surface::handle_midi_sysex, this, _1, _2, _3));
		/* V-Pot messages are Controller */
		p->controller.connect_same_thread (*this, boost::bind (&Surface::handle_midi_controller_message, this, _1, _2));
		/* Button messages are NoteOn */
		p->note_on.connect_same_thread (*this, boost::bind (&Surface::handle_midi_note_on_message, this, _1, _2));
		/* Button messages are NoteOn but libmidi++ sends note-on w/velocity = 0 as note-off so catch them too */
		p->note_off.connect_same_thread (*this, boost::bind (&Surface::handle_midi_note_on_message, this, _1, _2));
		/* Fader messages are Pitchbend */
		uint32_t i;
		for (i = 0; i < _mcp.device_info().strip_cnt(); i++) {
			p->channel_pitchbend[i].connect_same_thread (*this, boost::bind (&Surface::handle_midi_pitchbend_message, this, _1, _2, i));
		}
		// Master fader
		p->channel_pitchbend[_mcp.device_info().strip_cnt()].connect_same_thread (*this, boost::bind (&Surface::handle_midi_pitchbend_message, this, _1, _2, _mcp.device_info().strip_cnt()));

		_connected = true;
	}
}

void
Surface::handle_midi_pitchbend_message (MIDI::Parser&, MIDI::pitchbend_t pb, uint32_t fader_id)
{
	/* Pitchbend messages are fader position messages. Nothing in the data we get
	 * from the MIDI::Parser conveys the fader ID, which was given by the
	 * channel ID in the status byte.
	 *
	 * Instead, we have used bind() to supply the fader-within-strip ID
	 * when we connected to the per-channel pitchbend events.
	 */

	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Surface::handle_midi_pitchbend_message on port %3, fader = %1 value = %2 (%4)\n",
							   fader_id, pb, _number, pb/16383.0));

	if (_mcp.device_info().no_handshake()) {
		turn_it_on ();
	}

	Fader* fader = faders[fader_id];

	if (fader) {
		Strip* strip = dynamic_cast<Strip*> (&fader->group());
		float pos = pb / 16383.0;
		if (strip) {
			strip->handle_fader (*fader, pos);
		} else {
			DEBUG_TRACE (DEBUG::MackieControl, "Handling master fader\n");
			/* master fader */
			fader->set_value (pos); // alter master gain
			write (fader->set_position (pos)); // write back value (required for servo)
		}
	} else {
		DEBUG_TRACE (DEBUG::MackieControl, "fader not found\n");
	}
}

void
Surface::handle_midi_note_on_message (MIDI::Parser &, MIDI::EventTwoBytes* ev)
{
	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Surface::handle_midi_note_on_message %1 = %2\n", (int) ev->note_number, (int) ev->velocity));

	if (_mcp.device_info().no_handshake()) {
		turn_it_on ();
	}

	if (_mcp.device_info().device_type() == DeviceInfo::HUI && ev->note_number == 0 && ev->velocity == 127) {
		turn_it_on ();
	}

	/* fader touch sense is given by "buttons" 0xe..0xe7 and 0xe8 for the
	 * master.
	 */

	if (ev->note_number >= 0xE0 && ev->note_number <= 0xE8) {
		Fader* fader = faders[ev->note_number];

		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Surface: fader touch message, fader = %1\n", fader));

		if (fader) {

			Strip* strip = dynamic_cast<Strip*> (&fader->group());

			if (ev->velocity > 64) {
				strip->handle_fader_touch (*fader, true);
			} else {
				strip->handle_fader_touch (*fader, false);
			}
		}
		return;
	}

	Button* button = buttons[ev->note_number];

	if (button) {

		if (ev->velocity > 64) {
			button->pressed ();
		}

		Strip* strip = dynamic_cast<Strip*> (&button->group());

		if (strip) {
			DEBUG_TRACE (DEBUG::MackieControl, string_compose ("strip %1 button %2 pressed ? %3\n",
									   strip->index(), button->name(), (ev->velocity > 64)));
			strip->handle_button (*button, ev->velocity > 64 ? press : release);
		} else {
			/* global button */
			DEBUG_TRACE (DEBUG::MackieControl, string_compose ("global button %1\n", button->id()));
			_mcp.handle_button_event (*this, *button, ev->velocity > 64 ? press : release);
		}

		if (ev->velocity <= 64) {
			button->released ();
		}

	} else {
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("no button found for %1\n", (int) ev->note_number));
	}

	/* button release should reset timer AFTER handler(s) have run */
}

void
Surface::handle_midi_controller_message (MIDI::Parser &, MIDI::EventTwoBytes* ev)
{
	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("SurfacePort::handle_midi_controller %1 = %2\n", (int) ev->controller_number, (int) ev->value));

	if (_mcp.device_info().no_handshake()) {
		turn_it_on ();
	}

	Pot* pot = pots[ev->controller_number];

	// bit 6 gives the sign
	float sign = (ev->value & 0x40) == 0 ? 1.0 : -1.0;
	// bits 0..5 give the velocity. we interpret this as "ticks
	// moved before this message was sent"
	float ticks = (ev->value & 0x3f);
	if (ticks == 0) {
		/* euphonix and perhaps other devices send zero
		   when they mean 1, we think.
		*/
		ticks = 1;
	}

	float delta = 0;
	if (mcp().main_modifier_state() == MackieControlProtocol::MODIFIER_SHIFT) {
		delta = sign * (ticks / (float) 0xff);
	} else {
		delta = sign * (ticks / (float) 0x3f);
	}

	if (!pot) {
		if (ev->controller_number == Jog::ID && _jog_wheel) {

			DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Jog wheel moved %1\n", ticks));
			_jog_wheel->jog_event (delta);
			return;
		}
		// add external (pedal?) control here

		return;
	}

	Strip* strip = dynamic_cast<Strip*> (&pot->group());
	if (strip) {
		strip->handle_pot (*pot, delta);
	}
}

void
Surface::handle_midi_sysex (MIDI::Parser &, MIDI::byte * raw_bytes, size_t count)
{
	MidiByteArray bytes (count, raw_bytes);

	if (_mcp.device_info().no_handshake()) {
		turn_it_on ();
	}

	/* always save the device type ID so that our outgoing sysex messages
	 * are correct
	 */

	if (_stype == mcu) {
		if (_mcp.device_info().is_qcon()) {
			mackie_sysex_hdr_qcon[4] = bytes[4];
		} else {
			mackie_sysex_hdr[4] = bytes[4];
		}

	} else {
		if (_mcp.device_info().is_qcon()) {
			mackie_sysex_hdr_xt_qcon[4] = bytes[4];
		} else {
			mackie_sysex_hdr_xt[4] = bytes[4];
		}
	}

	switch (bytes[5]) {
	case 0x01:
		if (!_active) {
			DEBUG_TRACE (DEBUG::MackieControl, string_compose ("handle_midi_sysex: %1\n", bytes));
		}
		/* MCP: Device Ready
		   LCP: Connection Challenge
		*/
		if (bytes[4] == 0x10 || bytes[4] == 0x11) {
			DEBUG_TRACE (DEBUG::MackieControl, "Logic Control Device connection challenge\n");
			write_sysex (host_connection_query (bytes));
		} else {
			if (!_active) {
				DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Mackie Control Device ready, current status = %1\n", _active));
			}
			turn_it_on ();
		}
		break;

	case 0x06:
		if (!_active) {
			DEBUG_TRACE (DEBUG::MackieControl, string_compose ("handle_midi_sysex: %1\n", bytes));
		}
		/* Behringer X-Touch Compact: Device Ready
		*/
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Behringer X-Touch Compact ready, current status = %1\n", _active));
		turn_it_on ();
		break;

	case 0x03: /* LCP Connection Confirmation */
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("handle_midi_sysex: %1\n", bytes));
		DEBUG_TRACE (DEBUG::MackieControl, "Logic Control Device confirms connection, ardour replies\n");
		if (bytes[4] == 0x10 || bytes[4] == 0x11) {
			write_sysex (host_connection_confirmation (bytes));
			turn_it_on ();
		}
		break;

	case 0x04: /* LCP: Confirmation Denied */
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("handle_midi_sysex: %1\n", bytes));
		DEBUG_TRACE (DEBUG::MackieControl, "Logic Control Device denies connection\n");
		_active = false;
		break;

	default:
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("handle_midi_sysex: %1\n", bytes));
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("unknown device ID byte %1", (int) bytes[5]));
		error << "MCP: unknown sysex: " << bytes << endmsg;
	}
}

static MidiByteArray
calculate_challenge_response (MidiByteArray::iterator begin, MidiByteArray::iterator end)
{
	MidiByteArray l;
	back_insert_iterator<MidiByteArray> back  (l);
	copy (begin, end, back);

	MidiByteArray retval;

	// this is how to calculate the response to the challenge.
	// from the Logic docs.
	retval <<  (0x7f &  (l[0] +  (l[1] ^ 0xa) - l[3]));
	retval <<  (0x7f &  ( (l[2] >> l[3]) ^  (l[0] + l[3])));
	retval <<  (0x7f &  ((l[3] -  (l[2] << 2)) ^  (l[0] | l[1])));
	retval <<  (0x7f &  (l[1] - l[2] +  (0xf0 ^  (l[3] << 4))));

	return retval;
}

MidiByteArray
Surface::host_connection_query (MidiByteArray & bytes)
{
	MidiByteArray response;

	if (bytes[4] != 0x10 && bytes[4] != 0x11) {
		/* not a Logic Control device - no response required */
		return response;
	}

	// handle host connection query
	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("host connection query: %1\n", bytes));

	if  (bytes.size() != 18) {
		cerr << "expecting 18 bytes, read " << bytes << " from " << _port->input_port().name() << endl;
		return response;
	}

	// build and send host connection reply
	response << 0x02;
	copy (bytes.begin() + 6, bytes.begin() + 6 + 7, back_inserter (response));
	response << calculate_challenge_response (bytes.begin() + 6 + 7, bytes.begin() + 6 + 7 + 4);
	return response;
}

MidiByteArray
Surface::host_connection_confirmation (const MidiByteArray & bytes)
{
	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("host_connection_confirmation: %1\n", bytes));

	// decode host connection confirmation
	if  (bytes.size() != 14) {
		ostringstream os;
		os << "expecting 14 bytes, read " << bytes << " from " << _port->input_port().name();
		throw MackieControlException (os.str());
	}

	// send version request
	return MidiByteArray (2, 0x13, 0x00);
}

void
Surface::turn_it_on ()
{
	if (_active) {
		return;
	}

	_active = true;

	_mcp.device_ready ();

	for (Strips::iterator s = strips.begin(); s != strips.end(); ++s) {
		(*s)->notify_all ();
	}

	update_view_mode_display (false);

//	if (_mcp.device_info ().has_global_controls ()) {
//		_mcp.update_global_button (Button::Read, _mcp.metering_active ());
//	}
}

void
Surface::write_sysex (const MidiByteArray & mba)
{
	if (mba.empty()) {
		return;
	}

	MidiByteArray buf;
	buf << sysex_hdr() << mba << MIDI::eox;
	_port->write (buf);
}

void
Surface::write_sysex (MIDI::byte msg)
{
	MidiByteArray buf;
	buf << sysex_hdr() << msg << MIDI::eox;
	_port->write (buf);
}

uint32_t
Surface::n_strips (bool with_locked_strips) const
{
	if (with_locked_strips) {
		return strips.size();
	}

	uint32_t n = 0;

	for (Strips::const_iterator it = strips.begin(); it != strips.end(); ++it) {
		if (!(*it)->locked()) {
			++n;
		}
	}
	return n;
}

Strip*
Surface::nth_strip (uint32_t n) const
{
	if (n > n_strips()) {
		return 0;
	}
	return strips[n];
}

void
Surface::zero_all ()
{
	if (_mcp.device_info().has_timecode_display ()) {
		display_timecode (string (10, '0'), string (10, ' '));
	}

	if (_mcp.device_info().has_two_character_display()) {
		show_two_char_display (string (2, '0'), string (2, ' '));
	}

	if (_mcp.device_info().has_master_fader () && _master_fader) {
		_port->write (_master_fader->zero ());

		if (_has_master_display) {
			DEBUG_TRACE (DEBUG::MackieControl, "Surface::zero_all: Clearing Master display\n");
			_port->write (blank_master_display(0));
			_port->write (blank_master_display(1));
			pending_display[0] = string();
			pending_display[1] = string();
			current_display[0] = string();
			current_display[1] = string();
		}
		if (_has_master_meter) {
			_port->write (MidiByteArray (2, 0xd1, 0x00));
			_port->write (MidiByteArray (2, 0xd1, 0x10));
		}

	}

	// zero all strips
	for (Strips::iterator it = strips.begin(); it != strips.end(); ++it) {
		(*it)->zero();
	}

	zero_controls ();
}

void
Surface::zero_controls ()
{
	if (!_mcp.device_info().has_global_controls()) {
		return;
	}

	// turn off global buttons and leds

	for (Controls::iterator it = controls.begin(); it != controls.end(); ++it) {
		Control & control = **it;
		if (!control.group().is_strip()) {
			_port->write (control.zero());
		}
	}

	// and the led ring for the master strip
	blank_jog_ring ();

	_last_master_gain_written = 0.0f;
}

void
Surface::periodic (PBD::microseconds_t now_usecs)
{
	master_gain_changed();
	master_meter_changed();
	for (Strips::iterator s = strips.begin(); s != strips.end(); ++s) {
		(*s)->periodic (now_usecs);
	}
}

void
Surface::redisplay (PBD::microseconds_t now, bool force)
{
	if (_has_master_display) {
		if (force || (current_display[0] != pending_display[0])) {
			DEBUG_TRACE (DEBUG::MackieControl, "Surface::redisplay: Updating master display line 0\n");
			write (master_display (0, pending_display[0]));
			current_display[0] = pending_display[0];
		}

		if (force || (current_display[1] != pending_display[1])) {
			DEBUG_TRACE (DEBUG::MackieControl, "Surface::redisplay: Updating master display line 1\n");
			write (master_display (1, pending_display[1]));
			current_display[1] = pending_display[1];
		}
	}

	for (Strips::iterator s = strips.begin(); s != strips.end(); ++s) {
		(*s)->redisplay (now, force);
	}
}

void
Surface::write (const MidiByteArray& data)
{
	if (_active) {
		_port->write (data);
	} else {
		DEBUG_TRACE (DEBUG::MackieControl, "surface not active, write ignored\n");
	}
}

void
Surface::update_strip_selection ()
{
	Strips::iterator s = strips.begin();
	for ( ; s != strips.end(); ++s) {
		(*s)->update_selection_state();
	}
}

void
Surface::map_stripables (const vector<boost::shared_ptr<Stripable> >& stripables)
{
	vector<boost::shared_ptr<Stripable> >::const_iterator r;
	Strips::iterator s = strips.begin();

	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Mapping %1 stripables to %2 strips\n", stripables.size(), strips.size()));

	for (r = stripables.begin(); r != stripables.end() && s != strips.end(); ++s) {

		/* don't try to assign stripables to a locked strip. it won't
		   use it anyway, but if we do, then we get out of sync
		   with the proposed mapping.
		*/

		if (!(*s)->locked()) {
			(*s)->set_stripable (*r);
			++r;
		}
	}

	for (; s != strips.end(); ++s) {
		DEBUG_TRACE (DEBUG::MackieControl, string_compose ("strip %1 being set to null stripable\n", (*s)->index()));
		(*s)->set_stripable (boost::shared_ptr<Stripable>());
	}
}

static char
translate_seven_segment (char achar)
{
	achar = toupper (achar);

	if  (achar >= 0x40 && achar <= 0x5f) {
		return achar - 0x40;
	} else if  (achar >= 0x20 && achar <= 0x3f) {
		return achar;
	} else {
		return 0x20;
	}
}

void
Surface::show_two_char_display (const std::string & msg, const std::string & dots)
{
	if (_stype != mcu || !_mcp.device_info().has_two_character_display() || msg.length() != 2 || dots.length() != 2) {
		return;
	}

	MidiByteArray right (3, 0xb0, 0x4b, 0x00);
	MidiByteArray left (3, 0xb0, 0x4a, 0x00);

	right[2] = translate_seven_segment (msg[0]) +  (dots[0] == '.' ? 0x40 : 0x00);
	left[2] = translate_seven_segment (msg[1]) +  (dots[1] == '.' ? 0x40 : 0x00);

	_port->write (right);
	_port->write (left);
}

void
Surface::show_two_char_display (unsigned int value, const std::string & /*dots*/)
{
	ostringstream os;
	os << setfill('0') << setw(2) << value % 100;
	show_two_char_display (os.str());
}

void
Surface::display_timecode (const std::string & timecode, const std::string & last_timecode)
{
	//TODO: Fix for Qcon to correct timecode value if is over 1000 bars

	if (!_active || !_mcp.device_info().has_timecode_display()) {
		return;
	}
	// if there's no change, send nothing, not even sysex header
	if  (timecode == last_timecode) return;

	// length sanity checking
	string local_timecode = timecode;

	// truncate to 10 characters
	if  (local_timecode.length() > 10) {
		local_timecode = local_timecode.substr (0, 10);
	}

	// pad to 10 characters
	while  (local_timecode.length() < 10) {
		local_timecode += " ";
	}

	// translate characters.
	// Only the characters that actually changed are sent.
	int position = 0x3f;
	int i;
	for (i = local_timecode.length () - 1; i >= 0; i--) {
		position++;
		if (local_timecode[i] == last_timecode[i]) {
			continue;
		}
		MidiByteArray retval (2, 0xb0, position);
		retval << translate_seven_segment (local_timecode[i]);
		_port->write (retval);
	}
}

void
Surface::update_flip_mode_display ()
{
	for (Strips::iterator s = strips.begin(); s != strips.end(); ++s) {
		(*s)->flip_mode_changed ();
	}
}

void
Surface::subview_mode_changed ()
{
	show_master_name();
	for (Strips::iterator s = strips.begin(); s != strips.end(); ++s) {
		(*s)->subview_mode_changed ();
	}
}

void
Surface::update_view_mode_display (bool with_helpful_text)
{
	string text;
	int id = -1;

	if (!_active) {
		return;
	}

	switch (_mcp.view_mode()) {
	case MackieControlProtocol::Mixer:
		show_two_char_display ("Mx");
		id = Button::View;
		text = _("Mixer View");
		break;
	case MackieControlProtocol::AudioTracks:
		show_two_char_display ("AT");
		id = Button::AudioTracks;
		text = _("Audio Tracks");
		break;
	case MackieControlProtocol::MidiTracks:
		show_two_char_display ("MT");
		id = Button::MidiTracks;
		text = _("MIDI Tracks");
		break;
	case MackieControlProtocol::Busses:
		show_two_char_display ("BS");
		id = Button::Busses;
		if (Profile->get_mixbus()) {
			text = _("Mixbusses");
		} else {
			text = _("Busses");
		}
		break;
	case MackieControlProtocol::Auxes:
		show_two_char_display ("Au");
		id = Button::Aux;
		text = _("Auxes");
		break;
	case MackieControlProtocol::Outputs:
		show_two_char_display ("HI");
		id = Button::Outputs;
		text = _("Hidden Tracks");
		break;
	case MackieControlProtocol::Selected:
		show_two_char_display ("SE");
		id = Button::User;
		text = _("Selected Tracks");
		break;
	case MackieControlProtocol::AudioInstr:
		show_two_char_display ("IS");
		id = Button::AudioInstruments;
		text = _("Instruments");
		break;
	default:
		break;
	}

	vector<int> view_mode_buttons;
	view_mode_buttons.push_back (Button::View);
	view_mode_buttons.push_back (Button::Busses);
	view_mode_buttons.push_back (Button::Plugin);
	view_mode_buttons.push_back (Button::AudioTracks);
	view_mode_buttons.push_back (Button::MidiTracks);
	view_mode_buttons.push_back (Button::Aux);
	view_mode_buttons.push_back (Button::Outputs);
	view_mode_buttons.push_back (Button::User);
	view_mode_buttons.push_back (Button::Inputs);
	view_mode_buttons.push_back (Button::AudioInstruments);
	view_mode_buttons.push_back (Button::Outputs);

	if (id >= 0) {

		for (vector<int>::iterator i = view_mode_buttons.begin(); i != view_mode_buttons.end(); ++i) {
			map<int,Control*>::iterator x = controls_by_device_independent_id.find (*i);

			if (x != controls_by_device_independent_id.end()) {
				Button* button = dynamic_cast<Button*> (x->second);
				if (button) {
					bool onoff;
					onoff = (*i) == id;

					_port->write (button->set_state (onoff));
				}
			}
		}
	}

	if (with_helpful_text && !text.empty()) {
		display_message_for (text, 1000);
	}
}

void
Surface::say_hello ()
{
	/* wakeup for Mackie Control */
	MidiByteArray wakeup (7, MIDI::sysex, 0x00, 0x00, 0x66, 0x14, 0x00, MIDI::eox);
	_port->write (wakeup);
	wakeup[4] = 0x15; /* wakup Mackie XT */
	_port->write (wakeup);
	wakeup[4] = 0x10; /* wakeup Logic Control */
	_port->write (wakeup);
	wakeup[4] = 0x11; /* wakeup Logic Control XT */
	_port->write (wakeup);
}

void
Surface::next_jog_mode ()
{
	if (_jog_wheel) {
		if (_jog_wheel->mode() == JogWheel::scroll) {
			_jog_wheel->set_mode (JogWheel::shuttle);
		} else {
			_jog_wheel->set_mode (JogWheel::scroll);
		}
	}
}

void
Surface::set_jog_mode (JogWheel::Mode m)
{
	if (_jog_wheel) {
		_jog_wheel->set_mode (m);
	}
}

bool
Surface::stripable_is_locked_to_strip (boost::shared_ptr<Stripable> stripable) const
{
	for (Strips::const_iterator s = strips.begin(); s != strips.end(); ++s) {
		if ((*s)->stripable() == stripable && (*s)->locked()) {
			return true;
		}
	}
	return false;
}

bool
Surface::stripable_is_mapped (boost::shared_ptr<Stripable> stripable) const
{
	for (Strips::const_iterator s = strips.begin(); s != strips.end(); ++s) {
		if ((*s)->stripable() == stripable) {
			return true;
		}
	}

	return false;
}

void
Surface::notify_metering_state_changed()
{
	for (Strips::const_iterator s = strips.begin(); s != strips.end(); ++s) {
		(*s)->notify_metering_state_changed ();
	}
}

void
Surface::reset ()
{
	if (_port) {
		/* reset msg for Mackie Control */
		MidiByteArray msg;
		msg << sysex_hdr();
		msg << 0x08;
		msg << 0x00;
		msg << MIDI::eox;
		_port->write (msg);
	}
}

void
Surface::toggle_backlight ()
{
	if (_port) {
		int onoff = random() %2;
		MidiByteArray msg;
		msg << sysex_hdr ();
		msg << 0xa;
		msg << (onoff ? 0x1 : 0x0);
		msg << MIDI::eox;
		_port->write (msg);
	}
}

void
Surface::recalibrate_faders ()
{
	if (_port) {
		MidiByteArray msg;
		msg << sysex_hdr ();
		msg << 0x09;
		msg << 0x00;
		msg << MIDI::eox;
		_port->write (msg);
	}
}

void
Surface::set_touch_sensitivity (int sensitivity)
{
	/* NOTE: assumed called from GUI code, hence sleep() */

	/* sensitivity already clamped by caller */

	if( !is_qcon ) { // Qcon doesn't support fader sensitivity
		if (_port) {
			MidiByteArray msg;

			msg << sysex_hdr ();
			msg << 0x0e;
			msg << 0xff; /* overwritten for each fader below */
			msg << (sensitivity & 0x7f);
			msg << MIDI::eox;

			for (int fader = 0; fader < 9; ++fader) {
				msg[6] = fader;
				_port->write (msg);
			}
		}
	}
}

void
Surface::hui_heartbeat ()
{
	if (!_port) {
		return;
	}

	MidiByteArray msg (3, MIDI::on, 0x0, 0x0);
	_port->write (msg);
}

void
Surface::connected ()
{
	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Surface %1 now connected, trying to ping device...\n", _name));

	say_hello ();

	if (_mcp.device_info().no_handshake()) {
		turn_it_on ();
	}
}

MidiByteArray
Surface::display_line (string const& msg, int line_num)
{
	MidiByteArray midi_msg;
	midi_msg << sysex_hdr ();
	midi_msg << 0x12;
	midi_msg << (line_num ? 0x38 : 0x0); /* offsets into char array
	                                      * on device that
	                                      * correspond to line
	                                      * starts
	                                      */
	if (msg.empty()) {

		midi_msg.insert (midi_msg.end(), 55, ' ');

	} else {

		/* ascii data to display. @p msg is UTF-8 which is not legal. */
		string ascii = Glib::convert_with_fallback (msg, "UTF-8", "ISO-8859-1", "_");
		string::size_type len = ascii.length();

		if (len > 55) {
			midi_msg << ascii.substr (0, 55);
		} else {
			midi_msg << ascii;

			for (string::size_type i = len; i < 55; ++i) {
				midi_msg << ' ';
			}
		}
	}

	midi_msg << MIDI::eox;

	return midi_msg;
}

/** display @p msg on the 55x2 screen for @p msecs milliseconds
 *
 *  @param msg is assumed to be UTF-8 encoded, and will be converted
 *  to ASCII with an underscore as fallback character before being
 *  sent to the device.
 */
void
Surface::display_message_for (string const& msg, uint64_t msecs)
{
	string::size_type newline;

	if ((newline = msg.find ('\n')) == string::npos) {

		_port->write (display_line (msg, 0));
		_port->write (display_line (string(), 1));

	} else if (newline == 0) {

		_port->write (display_line (string(), 0));
		_port->write (display_line (msg.substr (1), 1));

	} else {

		string first_line = msg.substr (0, newline-1);
		string second_line = msg.substr (newline+1);

		_port->write (display_line (first_line, 0));
		_port->write (display_line (second_line.substr (0, second_line.find_first_of ('\n')), 1));
	}

	for (Strips::const_iterator s = strips.begin(); s != strips.end(); ++s) {
		(*s)->block_screen_display_for (msecs);
	}
}
