/*
    Copyright (C) 2002 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.

*/

#include <unistd.h>
#include <cerrno>
#include <vector>
#include <sstream>

#include <boost/scoped_ptr.hpp>

#include <glibmm/timer.h>
#include <jack/weakjack.h>
#include <pbd/pthread_utils.h>
#include <pbd/stacktrace.h>
#include <pbd/epa.h>

#include <ardour/audioengine.h>
#include <ardour/buffer.h>
#include <ardour/port.h>
#include <ardour/io.h>
#include <ardour/session.h>
#include <ardour/cycle_timer.h>
#include <ardour/utils.h>

#include <ardour/timestamps.h>

#include "i18n.h"

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

gint AudioEngine::m_meter_exit;
AudioEngine* AudioEngine::_instance = 0;

#define GET_PRIVATE_JACK_POINTER(j)  jack_client_t* _priv_jack = (jack_client_t*) (j); if (!_priv_jack) { return; }
#define GET_PRIVATE_JACK_POINTER_RET(j,r) jack_client_t* _priv_jack = (jack_client_t*) (j); if (!_priv_jack) { return r; }

typedef void (*_JackInfoShutdownCallback)(jack_status_t code, const char* reason, void *arg);

static void (*on_info_shutdown)(jack_client_t*, _JackInfoShutdownCallback, void *);
extern void jack_on_info_shutdown (jack_client_t*, _JackInfoShutdownCallback, void *) __attribute__((weak));

static void check_jack_symbols () __attribute__((constructor));

void check_jack_symbols ()
{
	/* use weak linking to see if we really have various late-model JACK function */
	on_info_shutdown = jack_on_info_shutdown;
}

static void 
ardour_jack_error (const char* msg) 
{
	// throw JACK errors away - they cause visual clutter
	// error << "JACK: " << msg << endmsg;
}

AudioEngine::AudioEngine (string client_name) 
	: ports (new Ports)
{
	_instance = this; /* singleton */

	session = 0;
	session_remove_pending = false;
	_running = false;
	_has_run = false;
	last_monitor_check = 0;
	monitor_check_interval = max_frames;
	_processed_frames = 0;
	_usecs_per_cycle = 0;
	_jack = 0;
	_frame_rate = 0;
	_buffer_size = 0;
	_freewheel_thread_registered = false;
	_freewheeling = false;

	m_meter_thread = 0;
	g_atomic_int_set (&m_meter_exit, 0);

	if (connect_to_jack (client_name)) {
		throw NoBackendAvailable ();
	}

        Port::_engine = this;
}

AudioEngine::~AudioEngine ()
{
	{
		Glib::Mutex::Lock tm (_process_lock);
		session_removed.signal ();
		
		if (_running) {
			jack_client_close (_jack);
			_jack = 0;
		}
		
		stop_metering_thread ();
	}
}

void
_thread_init_callback (void *arg)
{
	/* make sure that anybody who needs to know about this thread
	   knows about it.
	*/

	PBD::notify_gui_about_thread_creation (pthread_self(), X_("Audioengine"), 4096);
}

int
AudioEngine::start ()
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);

	if (!_running) {

		nframes_t blocksize = jack_get_buffer_size (_priv_jack);
		Port::set_buffer_size (blocksize);

		if (session) {

			BootMessage (_("Connect session to engine"));

			session->set_block_size (blocksize);
			session->set_frame_rate (jack_get_sample_rate (_priv_jack));

			/* page in as much of the session process code as we
			   can before we really start running.
			*/

			session->process (blocksize);
			session->process (blocksize);
			session->process (blocksize);
			session->process (blocksize);
			session->process (blocksize);
			session->process (blocksize);
			session->process (blocksize);
			session->process (blocksize);
		}

		_processed_frames = 0;
		last_monitor_check = 0;

		if (on_info_shutdown) {
			on_info_shutdown (_priv_jack, halted_info, this);
		} else {
			jack_on_shutdown (_priv_jack, halted, this);
		}

		jack_set_graph_order_callback (_priv_jack, _graph_order_callback, this);
		jack_set_thread_init_callback (_priv_jack, _thread_init_callback, this);
		jack_set_process_callback (_priv_jack, _process_callback, this);
		jack_set_sample_rate_callback (_priv_jack, _sample_rate_callback, this);
		jack_set_buffer_size_callback (_priv_jack, _bufsize_callback, this);
		jack_set_xrun_callback (_priv_jack, _xrun_callback, this);
		jack_set_sync_callback (_priv_jack, _jack_sync_callback, this);
		jack_set_freewheel_callback (_priv_jack, _freewheel_callback, this);

		if (Config->get_jack_time_master()) {
			jack_set_timebase_callback (_priv_jack, 0, _jack_timebase_callback, this);
		}

                if (jack_set_latency_callback) {
                        jack_set_latency_callback (_priv_jack, _latency_callback, this);
                }

		if (jack_activate (_priv_jack) == 0) {
			_running = true;
			_has_run = true;
			Running(); /* EMIT SIGNAL */
		} else {
			// error << _("cannot activate JACK client") << endmsg;
		}

		start_metering_thread();
	}

	return _running ? 0 : -1;
}

int
AudioEngine::stop (bool forever)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);

	if (_priv_jack) {
		if (forever) {
			disconnect_from_jack ();
		} else {
			jack_deactivate (_priv_jack);
			Stopped(); /* EMIT SIGNAL */
		}
	}
	
	stop_metering_thread ();

	return _running ? -1 : 0;
}


bool
AudioEngine::get_sync_offset (nframes_t& offset) const
{

#ifdef HAVE_JACK_VIDEO_SUPPORT

        GET_PRIVATE_JACK_POINTER_RET (_jack, false);

	jack_position_t pos;
	
	if (_priv_jack) {
		(void) jack_transport_query (_priv_jack, &pos);
		
		if (pos.valid & JackVideoFrameOffset) {
			offset = pos.video_offset;
			return true;
		}
	}

#endif

	return false;
}

void
AudioEngine::_jack_timebase_callback (jack_transport_state_t state, nframes_t nframes,
				      jack_position_t* pos, int new_position, void *arg)
{
	static_cast<AudioEngine*> (arg)->jack_timebase_callback (state, nframes, pos, new_position);
}

void
AudioEngine::jack_timebase_callback (jack_transport_state_t state, nframes_t nframes,
				     jack_position_t* pos, int new_position)
{
	if (_jack && session && session->synced_to_jack()) {
		session->jack_timebase_callback (state, nframes, pos, new_position);
	}
}

int
AudioEngine::_jack_sync_callback (jack_transport_state_t state, jack_position_t* pos, void* arg)
{
	return static_cast<AudioEngine*> (arg)->jack_sync_callback (state, pos);
}

int
AudioEngine::jack_sync_callback (jack_transport_state_t state, jack_position_t* pos)
{
	if (_jack && session) {
		return session->jack_sync_callback (state, pos);
	}

	return true;
}

int
AudioEngine::_xrun_callback (void *arg)
{
	AudioEngine* ae = static_cast<AudioEngine*> (arg);
	if (ae->connected()) {
		ae->Xrun (); /* EMIT SIGNAL */
	}
	return 0;
}

int
AudioEngine::_graph_order_callback (void *arg)
{
	AudioEngine* ae = static_cast<AudioEngine*> (arg);
	if (ae->connected()) {
		ae->GraphReordered (); /* EMIT SIGNAL */
	}
	return 0;
}

int
AudioEngine::_process_callback (nframes_t nframes, void *arg)
{
	return static_cast<AudioEngine *> (arg)->process_callback (nframes);
}

void
AudioEngine::_freewheel_callback (int onoff, void *arg)
{
	static_cast<AudioEngine*>(arg)->_freewheeling = onoff;
}

void
AudioEngine::_latency_callback (jack_latency_callback_mode_t mode, void* arg)
{
	return static_cast<AudioEngine *> (arg)->jack_latency_callback (mode);
}

void
AudioEngine::jack_latency_callback (jack_latency_callback_mode_t mode)
{
        if (session) {
                session->update_latency (mode == JackPlaybackLatency);
        }
}

int
AudioEngine::process_callback (nframes_t nframes)
{
	// CycleTimer ct ("AudioEngine::process");
        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);
	Glib::Mutex::Lock tm (_process_lock, Glib::TRY_LOCK);
	nframes_t next_processed_frames;
	
	/* handle wrap around of total frames counter */

	if (max_frames - _processed_frames < nframes) {
		next_processed_frames = nframes - (max_frames - _processed_frames);
	} else {
		next_processed_frames = _processed_frames + nframes;
	}
	
	if (!tm.locked() || session == 0) {
		_processed_frames = next_processed_frames;
		return 0;
	}

	if (session_remove_pending) {
		session = 0;
		session_remove_pending = false;
		session_removed.signal();
		_processed_frames = next_processed_frames;
		return 0;
	}

	/* reset port buffer offset for the start of a new cycle */

	Port::set_port_offset (0);

	/* tell all IO objects that we're starting a new cycle */

	IO::CycleStart (nframes);

	/* test if we are freewheeling and there are freewheel signals connected.
           ardour should act normally even when freewheeling unless /it/ is exporting */

	if (_freewheeling && !Freewheel.empty()) {
		if (Freewheel (nframes)) {
			jack_set_freewheel (_priv_jack, false);
		}
		return 0;
	}

	session->process (nframes);

	if (!_running) {
		/* we were zombified, maybe because a ladspa plugin took
		   too long, or jackd exited, or something like that.
		*/
		
		_processed_frames = next_processed_frames;
		return 0;
	}

	if (last_monitor_check + monitor_check_interval < next_processed_frames) {

		boost::shared_ptr<Ports> p = ports.reader();

		for (Ports::iterator i = p->begin(); i != p->end(); ++i) {
			
			Port *port = (*i);
			bool x;
			
			if (port->_last_monitor != (x = port->monitoring_input ())) {
				port->_last_monitor = x;
				/* XXX I think this is dangerous, due to 
				   a likely mutex in the signal handlers ...
				*/
				 port->MonitorInputChanged (x); /* EMIT SIGNAL */
			}
		}
		last_monitor_check = next_processed_frames;
	}

	if (session->silent()) {

		boost::shared_ptr<Ports> p = ports.reader();

		for (Ports::iterator i = p->begin(); i != p->end(); ++i) {
			
			Port *port = (*i);
			
			if (port->sends_output()) {
				Sample *buf = port->get_buffer (nframes);
				memset (buf, 0, sizeof(Sample) * nframes);
				// this should work but doesn't
				//port->silence(0, nframes);  //need to implement declicking fade
			}
		}
	}

	_processed_frames = next_processed_frames;
	return 0;
}

int
AudioEngine::_sample_rate_callback (nframes_t nframes, void *arg)
{
	return static_cast<AudioEngine *> (arg)->jack_sample_rate_callback (nframes);
}

int
AudioEngine::jack_sample_rate_callback (nframes_t nframes)
{
	_frame_rate = nframes;
	_usecs_per_cycle = (int) floor ((((double) frames_per_cycle() / nframes)) * 1000000.0);
	
	/* check for monitor input change every 1/10th of second */

	monitor_check_interval = nframes / 10;
	last_monitor_check = 0;
	
	if (session) {
		session->set_frame_rate (nframes);
	}

	SampleRateChanged (nframes); /* EMIT SIGNAL */

	return 0;
}

int
AudioEngine::_bufsize_callback (nframes_t nframes, void *arg)
{
	return static_cast<AudioEngine *> (arg)->jack_bufsize_callback (nframes);
}

int
AudioEngine::jack_bufsize_callback (nframes_t nframes)
{
	_buffer_size = nframes;
	_usecs_per_cycle = (int) floor ((((double) nframes / frame_rate())) * 1000000.0);
	last_monitor_check = 0;

	Port::set_buffer_size (nframes);

	boost::shared_ptr<Ports> p = ports.reader();
	
	for (Ports::iterator i = p->begin(); i != p->end(); ++i) {
		(*i)->reset();
	}

	if (session) {
		session->set_block_size (_buffer_size);
	}

	return 0;
}

void
AudioEngine::stop_metering_thread ()
{
	if (m_meter_thread) {
		g_atomic_int_set (&m_meter_exit, 1);
		m_meter_thread->join ();
		m_meter_thread = 0;
	}
}

void
AudioEngine::start_metering_thread ()
{
	if (m_meter_thread == 0) {
		g_atomic_int_set (&m_meter_exit, 0);
		m_meter_thread = Glib::Thread::create (sigc::mem_fun(this, &AudioEngine::meter_thread),
						       500000, true, true, Glib::THREAD_PRIORITY_NORMAL);
	}
}

void
AudioEngine::meter_thread ()
{
	while (true) {
		Glib::usleep (10000); /* 1/100th sec interval */
		if (g_atomic_int_get(&m_meter_exit)) {
			break;
		}
		IO::update_meters ();
	}
}

void 
AudioEngine::set_session (Session *s)
{
	Glib::Mutex::Lock pl (_process_lock);

	if (!session) {

		session = s;

		nframes_t blocksize = jack_get_buffer_size (_jack);
		
		/* page in as much of the session process code as we
		   can before we really start running.
		*/

		session->process (blocksize);
		session->process (blocksize);
		session->process (blocksize);
		session->process (blocksize);
		session->process (blocksize);
		session->process (blocksize);
		session->process (blocksize);
		session->process (blocksize);
	}
}

void 
AudioEngine::remove_session ()
{
	Glib::Mutex::Lock lm (_process_lock);

	if (_running) {

		if (session) {
			session_remove_pending = true;
			session_removed.wait(_process_lock);
		}

	} else {
		session = 0;
	}
	
	remove_all_ports ();
}

void
AudioEngine::port_registration_failure (const std::string& portname)
{
        GET_PRIVATE_JACK_POINTER (_jack);
	string full_portname = jack_client_name;
	full_portname += ':';
	full_portname += portname;
	
	
	jack_port_t* p = jack_port_by_name (_priv_jack, full_portname.c_str());
	string reason;
	
	if (p) {
		reason = string_compose (_("a port with the name \"%1\" already exists: check for duplicated track/bus names"), portname);
	} else {
		reason = string_compose (_("No more JACK ports are available. You will need to stop %1 and restart JACK with ports if you need this many tracks."),
					 PROGRAM_NAME);
	}

        cerr << " port reg failed: " << reason << endl;
	
	throw PortRegistrationFailure (string_compose (_("AudioEngine: cannot register port \"%1\": %2"), portname, reason).c_str());
}	

Port *
AudioEngine::register_input_port (DataType type, const string& portname)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,   0);
	if (!_running) {
		if (!_has_run) {
			fatal << _("register input port called before engine was started") << endmsg;
			/*NOTREACHED*/
		} else {
			return 0;
		}
	}

	jack_port_t *p = jack_port_register (_priv_jack, portname.c_str(), type.to_jack_type(), JackPortIsInput, 0);

	if (p) {

		Port *newport;

		if ((newport = new Port (p)) != 0) {
			RCUWriter<Ports> writer (ports);
			boost::shared_ptr<Ports> ps = writer.get_copy ();
			ps->insert (ps->begin(), newport);
			/* writer goes out of scope, forces update */
		}

		return newport;

	} else {
		port_registration_failure (portname);
	}

	return 0;
}

Port *
AudioEngine::register_output_port (DataType type, const string& portname)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, 0);

	if (!_running) {
		if (!_has_run) {
			fatal << _("register output port called before engine was started") << endmsg;
			/*NOTREACHED*/
		} else {
			return 0;
		}
	}

	jack_port_t *p;

	if ((p = jack_port_register (_priv_jack, portname.c_str(),
		type.to_jack_type(), JackPortIsOutput, 0)) != 0) {

		Port *newport = 0;

		{
			RCUWriter<Ports> writer (ports);
			boost::shared_ptr<Ports> ps = writer.get_copy ();
			
			newport = new Port (p);
			ps->insert (ps->begin(), newport);

			/* writer goes out of scope, forces update */
		}

		return newport;

	} else {
		port_registration_failure (portname);
	}

	return 0;
}


int          
AudioEngine::unregister_port (Port *port)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,-1);

	if (!_running) { 
		/* probably happening when the engine has been halted by JACK,
		   in which case, there is nothing we can do here.
		*/
		return 0;
	}

	if (port) {

		int ret = jack_port_unregister (_priv_jack, port->_port);
		
		if (ret == 0) {
			
			{

				RCUWriter<Ports> writer (ports);
				boost::shared_ptr<Ports> ps = writer.get_copy ();
				
				for (Ports::iterator i = ps->begin(); i != ps->end(); ++i) {
					if ((*i) == port) {
						ps->erase (i);
						break;
					}
				}

				/* writer goes out of scope, forces update */
			}

			remove_connections_for (port);
		}

		return ret;

	} else {
		return -1;
	}
}

int 
AudioEngine::connect (const string& source, const string& destination)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);

	string s = make_port_name_non_relative (source);
	string d = make_port_name_non_relative (destination);

	int ret = jack_connect (_priv_jack, s.c_str(), d.c_str());

	if (ret == 0) {
		pair<string,string> c (s, d);
		port_connections.push_back (c);
	} else if (ret == EEXIST) {
		error << string_compose(_("AudioEngine: connection already exists: %1 (%2) to %3 (%4)"), 
				 source, s, destination, d) 
		      << endmsg;
	} else {
		error << string_compose(_("AudioEngine: cannot connect %1 (%2) to %3 (%4)"), 
				 source, s, destination, d) 
		      << endmsg;
	}

	return ret;
}

int 
AudioEngine::disconnect (const string& source, const string& destination)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,-1);
     
	if (!_running) {
		if (!_has_run) {
			fatal << _("disconnect called before engine was started") << endmsg;
			/*NOTREACHED*/
		} else {
			return -1;
		}
	}
	
	string s = make_port_name_non_relative (source);
	string d = make_port_name_non_relative (destination);

	int ret = jack_disconnect (_priv_jack, s.c_str(), d.c_str());

	if (ret == 0) {
		pair<string,string> c (s, d);
		PortConnections::iterator i;
		
		if ((i = find (port_connections.begin(), port_connections.end(), c)) != port_connections.end()) {
			port_connections.erase (i);
		}
	}
	 
	return ret;
}

int
AudioEngine::disconnect (Port *port)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,-1);

	if (!_running) {
		if (!_has_run) {
			fatal << _("disconnect called before engine was started") << endmsg;
			/*NOTREACHED*/
		} else {
			return -1;
		}
	}

	int ret = jack_port_disconnect (_priv_jack, port->_port);

	if (ret == 0) {
		remove_connections_for (port);
	}

	return ret;

}

nframes_t
AudioEngine::frame_rate ()
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,0);
	if (_frame_rate == 0) {
	  return (_frame_rate = jack_get_sample_rate (_priv_jack));
	} else {
	  return _frame_rate;
	}
}

nframes_t
AudioEngine::frames_per_cycle ()
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,0);
	if (_buffer_size == 0) {
	  return (_buffer_size = jack_get_buffer_size (_jack));
	} else {
	  return _buffer_size;
	}
}

Port *
AudioEngine::get_port_by_name (const string& portname, bool keep)
{
	Glib::Mutex::Lock lm (_process_lock);
        GET_PRIVATE_JACK_POINTER_RET (_jack,0);

	if (!_running) {
		if (!_has_run) {
			fatal << _("get_port_by_name() called before engine was started") << endmsg;
			/*NOTREACHED*/
		} else {
			return 0;
		}
	}
	
	/* check to see if we have a Port for this name already */

	boost::shared_ptr<Ports> pr = ports.reader();
	
	for (Ports::iterator i = pr->begin(); i != pr->end(); ++i) {
		if (portname == (*i)->name()) {
			return (*i);
		}
	}

	jack_port_t *p;

	if ((p = jack_port_by_name (_priv_jack, portname.c_str())) != 0) {
		Port *newport = new Port (p);

		{
			if (keep && newport->is_mine (_jack)) {
				RCUWriter<Ports> writer (ports);
				boost::shared_ptr<Ports> ps = writer.get_copy ();
				ps->insert (newport);
				/* writer goes out of scope, forces update */
			}
		}

		return newport;

	} else {

		return 0;
	}
}

Port *
AudioEngine::get_ardour_port_by_name_unlocked (const string& portname)
{
	if (!_running) {
		if (!_has_run) {
			fatal << _("get_port_by_name() called before engine was started") << endmsg;
			/*NOTREACHED*/
		} else {
			return 0;
		}
	}

        if (!port_is_mine (portname)) {
                return 0;
        }
        
        std::string const rel = make_port_name_relative (portname);

	boost::shared_ptr<Ports> pr = ports.reader();
	
	for (Ports::iterator i = pr->begin(); i != pr->end(); ++i) {
		if (rel == (*i)->name()) {
			return (*i);
		}
	}

        return 0;
}

const char **
AudioEngine::get_ports (const string& port_name_pattern, const string& type_name_pattern, uint32_t flags)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,0);
	if (!_running) {
		if (!_has_run) {
			fatal << _("get_ports called before engine was started") << endmsg;
			/*NOTREACHED*/
		} else {
			return 0;
		}
	}
	return jack_get_ports (_priv_jack, port_name_pattern.c_str(), type_name_pattern.c_str(), flags);
}

void
AudioEngine::halted (void *arg)
{
        /* called from jack shutdown handler  */

	AudioEngine* ae = static_cast<AudioEngine *> (arg);
	bool was_running = ae->_running;

	ae->stop_metering_thread ();

	ae->_running = false;
	ae->_buffer_size = 0;
	ae->_frame_rate = 0;
	ae->_jack = 0;

	if (was_running) {
		ae->Halted(""); /* EMIT SIGNAL */
	}
}

void
AudioEngine::halted_info (jack_status_t code, const char* reason, void *arg)
{
        /* called from jack shutdown handler  */

	AudioEngine* ae = static_cast<AudioEngine *> (arg);
	bool was_running = ae->_running;

	ae->stop_metering_thread ();

	ae->_running = false;
	ae->_buffer_size = 0;
	ae->_frame_rate = 0;
	ae->_jack = 0;

	if (was_running) {
#ifdef HAVE_JACK_ON_INFO_SHUTDOWN
		switch (code) {
		case JackBackendError:
			ae->Halted(reason); /* EMIT SIGNAL */
			break;
		default:
			ae->Halted(""); /* EMIT SIGNAL */
		}
#else
		ae->Halted(""); /* EMIT SIGNAL */
#endif
	}
}

void
AudioEngine::died ()
{
        /* called from a signal handler for SIGPIPE */

	stop_metering_thread ();

        _running = false;
	_buffer_size = 0;
	_frame_rate = 0;
	_jack = 0;
}

bool
AudioEngine::can_request_hardware_monitoring () 
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,false);
	const char ** ports;

	if ((ports = jack_get_ports (_priv_jack, NULL, JACK_DEFAULT_AUDIO_TYPE, JackPortCanMonitor)) == 0) {
		return false;
	}

	free (ports);

	return true;
}


uint32_t
AudioEngine::n_physical_audio_outputs () const
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,0);
	const char ** ports;
	uint32_t i = 0;

	if ((ports = jack_get_ports (_priv_jack, NULL, JACK_DEFAULT_AUDIO_TYPE, JackPortIsPhysical|JackPortIsInput)) == 0) {
		return 0;
	}

	for (i = 0; ports[i]; ++i);
	free (ports);

	return i;
}

uint32_t
AudioEngine::n_physical_audio_inputs () const
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,0);
	const char ** ports;
	uint32_t i = 0;
	
	if ((ports = jack_get_ports (_priv_jack, NULL, JACK_DEFAULT_AUDIO_TYPE, JackPortIsPhysical|JackPortIsOutput)) == 0) {
		return 0;
	}

	for (i = 0; ports[i]; ++i);
	free (ports);

	return i;
}

void
AudioEngine::get_physical_audio_inputs (vector<string>& ins)
{
        GET_PRIVATE_JACK_POINTER (_jack);
	const char ** ports;
	uint32_t i = 0;
	
	if ((ports = jack_get_ports (_priv_jack, NULL, JACK_DEFAULT_AUDIO_TYPE, JackPortIsPhysical|JackPortIsOutput)) == 0) {
		return;
	}

	for (i = 0; ports[i]; ++i) {
		ins.push_back (ports[i]);
	}

	free (ports);
}

void
AudioEngine::get_physical_audio_outputs (vector<string>& outs)
{
        GET_PRIVATE_JACK_POINTER (_jack);
	const char ** ports;
	uint32_t i = 0;
	
	if ((ports = jack_get_ports (_priv_jack, NULL, JACK_DEFAULT_AUDIO_TYPE, JackPortIsPhysical|JackPortIsInput)) == 0) {
		return;
	}

	for (i = 0; ports[i]; ++i) {
		outs.push_back (ports[i]);
	}

	free (ports);
}

string
AudioEngine::get_nth_physical_audio (uint32_t n, int flag)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,"");
	const char ** ports;
	uint32_t i;
	string ret;

	if ((ports = jack_get_ports (_priv_jack, NULL, JACK_DEFAULT_AUDIO_TYPE, JackPortIsPhysical|flag)) == 0) {
		return ret;
	}

	for (i = 0; i < n && ports[i]; ++i);

	if (ports[i]) {
		ret = ports[i];
	}

	free (ports);

	return ret;
}

void
AudioEngine::transport_stop ()
{
        GET_PRIVATE_JACK_POINTER (_jack);
	// cerr << "tell jack to stop\n";
	jack_transport_stop (_priv_jack);
}

void
AudioEngine::transport_start ()
{
        GET_PRIVATE_JACK_POINTER (_jack);
	// cerr << "tell jack to roll\n";
	jack_transport_start (_priv_jack);
}

void
AudioEngine::transport_locate (nframes_t where)
{
        GET_PRIVATE_JACK_POINTER (_jack);
	// cerr << "tell JACK to locate to " << where << endl;
	jack_transport_locate (_priv_jack, where);
}

AudioEngine::TransportState
AudioEngine::transport_state ()
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, ((TransportState) JackTransportStopped));
	jack_position_t pos;
	return (TransportState) jack_transport_query (_priv_jack, &pos);
}

int
AudioEngine::reset_timebase ()
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);
	if (Config->get_jack_time_master()) {
	  return jack_set_timebase_callback (_priv_jack, 0, _jack_timebase_callback, this);
	} else {
	  return jack_release_timebase (_jack);
	}
}

int
AudioEngine::freewheel (bool onoff)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);

	if (onoff != _freewheeling) {
	  
	  if (onoff) {
	    _freewheel_thread_registered = false;
	  }
	  
	  return jack_set_freewheel (_priv_jack, onoff);
	  
	} else {
	  /* already doing what has been asked for */
	  return 0;
	}
}

void
AudioEngine::remove_all_ports ()
{
       jack_client_t* _priv_jack = _jack;

	/* process lock MUST be held */

       if (_priv_jack) {

	 boost::shared_ptr<Ports> p = ports.reader();
	 
	 for (Ports::iterator i = p->begin(); i != p->end(); ++i) {
	   jack_port_unregister (_priv_jack, (*i)->_port);
	 }
       }
       {
	 RCUWriter<Ports> writer (ports);
	 boost::shared_ptr<Ports> ps = writer.get_copy ();
	 ps->clear ();
       }
       
       port_connections.clear ();
}

void
AudioEngine::remove_connections_for (Port* port)
{
	for (PortConnections::iterator i = port_connections.begin(); i != port_connections.end(); ) {
		PortConnections::iterator tmp;
		
		tmp = i;
		++tmp;
		
		if ((*i).first == port->name()) {
			port_connections.erase (i);
		}

		i = tmp;
	}
}

#ifdef HAVE_JACK_CLIENT_OPEN

int
AudioEngine::connect_to_jack (string client_name)
{
        EnvironmentalProtectionAgency* global_epa = EnvironmentalProtectionAgency::get_global_epa ();
        boost::scoped_ptr<EnvironmentalProtectionAgency> current_epa;
	jack_options_t options = JackNullOption;
	jack_status_t status;
	const char *server_name = NULL;

        /* revert all environment settings back to whatever they were when ardour started
         */

        if (global_epa) {
                current_epa.reset (new EnvironmentalProtectionAgency(true)); /* will restore settings when we leave scope */
                global_epa->restore ();
        }

	jack_client_name = client_name; /* might be reset below */
	_jack = jack_client_open (jack_client_name.c_str(), options, &status, server_name);

	if (_jack == NULL) {
		/* just return without an error message. something else will take care of it */
		return -1;
	}

        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);

	if (status & JackNameNotUnique) {
		jack_client_name = jack_get_client_name (_priv_jack);
	}

	jack_set_error_function (ardour_jack_error);
	
	return 0;
}

#else

int
AudioEngine::connect_to_jack (string client_name)
{
	jack_client_name = client_name;

	if ((_jack = jack_client_new (client_name.c_str())) == 0) {
		return -1;
	}

	return 0;
}

#endif /* HAVE_JACK_CLIENT_OPEN */

int 
AudioEngine::disconnect_from_jack ()
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, 0);

	if (_running) {
		stop_metering_thread ();
	}

	{ 
		Glib::Mutex::Lock lm (_process_lock);
		jack_client_close (_priv_jack);
		_jack = 0;
	}

	_buffer_size = 0;
	_frame_rate = 0;

	if (_running) {
		_running = false;
		Stopped(); /* EMIT SIGNAL */
	}

	return 0;
}

int
AudioEngine::reconnect_to_jack ()
{
	if (_running) {
		disconnect_from_jack ();
		/* XXX give jackd a chance */
		Glib::usleep (250000);
	}

	if (connect_to_jack (jack_client_name)) {
		error << _("failed to connect to JACK") << endmsg;
		return -1;
	}

	/* Now that we're connected again, we can get a private
	   pointer to the jack client.
	*/

        GET_PRIVATE_JACK_POINTER_RET (_jack,-1);

	Ports::iterator i;
	boost::shared_ptr<Ports> p = ports.reader ();

	for (i = p->begin(); i != p->end(); ++i) {

		/* XXX hack hack hack */

		string long_name = (*i)->name();
		string short_name;
		
		short_name = long_name.substr (long_name.find_last_of (':') + 1);

		if (((*i)->_port = jack_port_register (_priv_jack, short_name.c_str(), (*i)->type(), (*i)->flags(), 0)) == 0) {
			error << string_compose (_("could not reregister %1"), (*i)->name()) << endmsg;
			break;
		} else {
		}

		(*i)->reset ();
	}

	if (i != p->end()) {
		/* failed */
		for (Ports::iterator i = p->begin(); i != p->end(); ++i) {
			jack_port_unregister (_priv_jack, (*i)->_port);
		}
		return -1;
	} 


	if (session) {
		session->reset_jack_connection (_priv_jack);
                
                nframes_t blocksize;

#ifdef HAVE_JACK_PORT_TYPE_GET_BUFFER_SIZE
                if (jack_port_type_get_buffer_size) {
                        blocksize = jack_port_type_get_buffer_size (_priv_jack, JACK_DEFAULT_AUDIO_TYPE);
                } else {
                        warning << _("This version of JACK is old - you should upgrade to a newer version that supports jack_port_type_get_buffer_size()") << endmsg;
                        blocksize = jack_get_buffer_size (_priv_jack);
                }
#else
                blocksize = jack_get_buffer_size (_priv_jack);
#endif
                
		Port::set_buffer_size (blocksize);
		session->set_block_size (blocksize);
		session->set_frame_rate (jack_get_sample_rate (_priv_jack));
	}

	last_monitor_check = 0;
	
	jack_on_shutdown (_priv_jack, halted, this);
	jack_set_graph_order_callback (_priv_jack, _graph_order_callback, this);
	jack_set_thread_init_callback (_priv_jack, _thread_init_callback, this);
	jack_set_process_callback (_priv_jack, _process_callback, this);
	jack_set_sample_rate_callback (_priv_jack, _sample_rate_callback, this);
	jack_set_buffer_size_callback (_priv_jack, _bufsize_callback, this);
	jack_set_xrun_callback (_priv_jack, _xrun_callback, this);
	jack_set_sync_callback (_priv_jack, _jack_sync_callback, this);
	jack_set_freewheel_callback (_priv_jack, _freewheel_callback, this);
	
	if (Config->get_jack_time_master()) {
		jack_set_timebase_callback (_priv_jack, 0, _jack_timebase_callback, this);
	} 
	
        if (jack_set_latency_callback) {
                jack_set_latency_callback (_priv_jack, _latency_callback, this);
        }

	if (jack_activate (_priv_jack) == 0) {
		_running = true;
		_has_run = true;
	} else {
		return -1;
	}

	/* re-establish connections */
	
	for (PortConnections::iterator i = port_connections.begin(); i != port_connections.end(); ++i) {
		
		int err;

		if (!_jack) {
			error << string_compose (_("Disconnected from JACK while reconnecting. You should quit %1 now."), PROGRAM_NAME) << endmsg;
			return -1;
		}

		if ((err = jack_connect (_priv_jack, (*i).first.c_str(), (*i).second.c_str())) != 0) {
			if (err != EEXIST) {
				error << string_compose (_("could not reconnect %1 and %2 (err = %3)"),
						  (*i).first, (*i).second, err)
				      << endmsg;
			}
		}
	}

	Running (); /* EMIT SIGNAL*/

	start_metering_thread ();

	return 0;
}

int
AudioEngine::request_buffer_size (nframes_t nframes)
{
        GET_PRIVATE_JACK_POINTER_RET (_jack, -1);

	if (nframes == jack_get_buffer_size (_priv_jack)) {
	  return 0;
	}
	
	return jack_set_buffer_size (_priv_jack, nframes);
}

string
AudioEngine::make_port_name_relative (string portname)
{
	string::size_type len;
	string::size_type n;
	
	len = portname.length();

	for (n = 0; n < len; ++n) {
		if (portname[n] == ':') {
			break;
		}
	}
	
	if ((n != len) && (portname.substr (0, n) == jack_client_name)) {
		return portname.substr (n+1);
	}

	return portname;
}

string
AudioEngine::make_port_name_non_relative (string portname)
{
	string str;

	if (portname.find_first_of (':') != string::npos) {
		return portname;
	}

	str  = jack_client_name;
	str += ':';
	str += portname;
	
	return str;
}

bool
AudioEngine::is_realtime () const
{
        GET_PRIVATE_JACK_POINTER_RET (_jack,false);
	return jack_is_realtime (_priv_jack);
}

bool
AudioEngine::port_is_mine (const string& portname) const
{
	if (portname.find_first_of (':') != string::npos) {
		if (portname.substr (0, jack_client_name.length ()) != jack_client_name) {
                        return false;
                }
        }
        return true;
}