/*
    Copyright (C) 2006 Paul Davis
 
    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., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#define __STDC_FORMAT_MACROS 1
#include <stdint.h>

#include <algorithm>

#include "pbd/error.h"
#include "pbd/failed_constructor.h"

#include "midi++/port.h"
#include "midi++/manager.h"

#include "ardour/session.h"
#include "ardour/route.h"
#include "ardour/midi_ui.h"

#include "generic_midi_control_protocol.h"
#include "midicontrollable.h"

using namespace ARDOUR;
using namespace PBD;

#include "i18n.h"

#define midi_ui_context() MidiControlUI::instance() /* a UICallback-derived object that specifies the event loop for signal handling */
#define ui_bind(x) boost::protect (boost::bind ((x)))

GenericMidiControlProtocol::GenericMidiControlProtocol (Session& s)
	: ControlProtocol (s, _("Generic MIDI"), MidiControlUI::instance())
{
	MIDI::Manager* mm = MIDI::Manager::instance();

	/* XXX it might be nice to run "control" through i18n, but thats a bit tricky because
	   the name is defined in ardour.rc which is likely not internationalized.
	*/
	
	_port = mm->port (X_("control"));

	if (_port == 0) {
		error << _("no MIDI port named \"control\" exists - generic MIDI control disabled") << endmsg;
		throw failed_constructor();
	}

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

	/* XXX is it right to do all these in the same thread as whatever emits the signal? */

	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));
	Controllable::CreateBinding.connect_same_thread (*this, boost::bind (&GenericMidiControlProtocol::create_binding, this, _1, _2, _3));
	Controllable::DeleteBinding.connect_same_thread (*this, boost::bind (&GenericMidiControlProtocol::delete_binding, this, _1));

	Session::SendFeedback.connect (*this, boost::bind (&GenericMidiControlProtocol::send_feedback, this), midi_ui_context());;
}

GenericMidiControlProtocol::~GenericMidiControlProtocol ()
{
}

int
GenericMidiControlProtocol::set_active (bool /*yn*/)
{
	/* start/stop delivery/outbound thread */
	return 0;
}

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

void 
GenericMidiControlProtocol::send_feedback ()
{
	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 ()
{
	const int32_t bufsize = 16 * 1024; /* XXX too big */
	MIDI::byte buf[bufsize];
	int32_t bsize = bufsize;
	MIDI::byte* end = buf;
	
	for (MIDIControllables::iterator r = controllables.begin(); r != controllables.end(); ++r) {
		end = (*r)->write_feedback (end, bsize);
	}
	
	if (end == buf) {
		return;
	} 

	_port->write (buf, (int32_t) (end - buf), 0);
}

bool
GenericMidiControlProtocol::start_learning (Controllable* c)
{
	if (c == 0) {
		return false;
	}

	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;
	}

	MIDIPendingControllables::iterator ptmp;
	for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ) {
		ptmp = i;
		++ptmp;
		if (((*i)->first)->get_controllable() == c) {
			(*i)->second.disconnect();
			delete (*i)->first;
			delete *i;
			pending_controllables.erase (i);
		}
		i = ptmp;
	}


	MIDIControllable* mc = 0;

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

	if (!mc) {
		mc = new MIDIControllable (*_port, *c);
	}
	
	{
		Glib::Mutex::Lock lm (pending_lock);

		MIDIPendingControllable* element = new MIDIPendingControllable;
		element->first = mc;
		c->LearningFinished.connect_same_thread (element->second, 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::Mutex::Lock lm (pending_lock);
	Glib::Mutex::Lock lm2 (controllables_lock);
	
	MIDIPendingControllables::iterator tmp;

	for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ) {
		tmp = i;
		++tmp;

		if ( (*i)->first == mc) {
			(*i)->second.disconnect();
			delete *i;
			pending_controllables.erase(i);
		}

		i = tmp;
	}

	controllables.insert (mc);
}

void
GenericMidiControlProtocol::stop_learning (Controllable* c)
{
	Glib::Mutex::Lock lm (pending_lock);
	Glib::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)->first)->get_controllable() == c) {
			(*i)->first->stop_learning ();
			dptr = (*i)->first;
			(*i)->second.disconnect();

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

void
GenericMidiControlProtocol::delete_binding (PBD::Controllable* control)
{
	if (control != 0) {
		Glib::Mutex::Lock lm2 (controllables_lock);
		
		for (MIDIControllables::iterator iter = controllables.begin(); iter != controllables.end(); ++iter) {
			MIDIControllable* existingBinding = (*iter);
			
			if (control == (existingBinding->get_controllable())) {
				delete existingBinding;
				controllables.erase (iter);
			}
			
		}
	}
}

void
GenericMidiControlProtocol::create_binding (PBD::Controllable* control, int pos, int control_number)
{
	if (control != NULL) {
		Glib::Mutex::Lock lm2 (controllables_lock);
		
		MIDI::channel_t channel = (pos & 0xf);
		MIDI::byte value = control_number;
		
		// Create a MIDIControllable
		MIDIControllable* mc = new MIDIControllable (*_port, *control);
		
		// Remove any old binding for this midi channel/type/value pair
		// Note:  can't use delete_binding() here because we don't know the specific controllable we want to remove, only the midi information
		for (MIDIControllables::iterator iter = controllables.begin(); iter != controllables.end(); ++iter) {
			MIDIControllable* existingBinding = (*iter);
			
			if ((existingBinding->get_control_channel() & 0xf ) == channel &&
			    existingBinding->get_control_additional() == value &&
			    (existingBinding->get_control_type() & 0xf0 ) == MIDI::controller) {
				
				delete existingBinding;
				controllables.erase (iter);
			}
			
		}
		
		// Update the MIDI Controllable based on the the pos param
		// Here is where a table lookup for user mappings could go; for now we'll just wing it...
		mc->bind_midi(channel, MIDI::controller, value);
		
		controllables.insert (mc);
	}
}

XMLNode&
GenericMidiControlProtocol::get_state () 
{
	XMLNode* node = new XMLNode ("Protocol"); 
	char buf[32];

	node->add_property (X_("name"), _name);
	node->add_property (X_("feedback"), do_feedback ? "1" : "0");
	snprintf (buf, sizeof (buf), "%" PRIu64, _feedback_interval);
	node->add_property (X_("feedback_interval"), buf);

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

	node->add_child_nocopy (*children);

	Glib::Mutex::Lock lm2 (controllables_lock);
	for (MIDIControllables::iterator i = controllables.begin(); i != controllables.end(); ++i) {
		children->add_child_nocopy ((*i)->get_state());
	}

	return *node;
}

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

	if ((prop = node.property ("feedback")) != 0) {
		do_feedback = (bool) atoi (prop->value().c_str());
	} else {
		do_feedback = false;
	}

	if ((prop = node.property ("feedback_interval")) != 0) {
		if (sscanf (prop->value().c_str(), "%" PRIu64, &_feedback_interval) != 1) {
			_feedback_interval = 10000;
		}
	} else {
		_feedback_interval = 10000;
	}

	boost::shared_ptr<Controllable> c;
	
	{
		Glib::Mutex::Lock lm (pending_lock);
		for (MIDIPendingControllables::iterator i = pending_controllables.begin(); i != pending_controllables.end(); ++i) {
			delete *i;
		}
		pending_controllables.clear ();
	}
	
	Glib::Mutex::Lock lm2 (controllables_lock);
	controllables.clear ();
	nlist = node.children(); // "controls"
	
	if (nlist.empty()) {
		return 0;
	}
	
	nlist = nlist.front()->children ();
		
	for (niter = nlist.begin(); niter != nlist.end(); ++niter) {
		
		if ((prop = (*niter)->property ("id")) != 0) {
			
			ID id = prop->value ();
			c = session->controllable_by_id (id);
			
			if (c) {
				MIDIControllable* mc = new MIDIControllable (*_port, *c);
				if (mc->set_state (**niter, version) == 0) {
					controllables.insert (mc);
				}
				
			} else {
				warning << string_compose (
					_("Generic MIDI control: controllable %1 not found in session (ignored)"),
					id) << 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;
}