/*
 * Copyright (C) 2013-2019 Paul Davis <paul@linuxaudiosystems.com>
 * Copyright (C) 2015-2018 Robin Gareus <robin@gareus.org>
 *
 * 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 <iostream>
#include <cerrno>

#include "ardour/audioengine.h"
#include "ardour/audio_backend.h"
#include "ardour/session.h"
#include "ardour/transport_master.h"

#include "pbd/i18n.h"

using namespace std;
using namespace ARDOUR;

Engine_TransportMaster::Engine_TransportMaster (AudioEngine& e)
	: TransportMaster (Engine, X_("JACK"))
	, engine (e)
	, _starting (false)
{
	check_backend ();
}

Engine_TransportMaster::~Engine_TransportMaster ()
{
}

void
Engine_TransportMaster::init ()
{
}

bool
Engine_TransportMaster::usable () const
{
	return AudioEngine::instance()->current_backend_name() == X_("JACK");
}

void
Engine_TransportMaster::check_backend()
{
	if (AudioEngine::instance()->current_backend_name() == X_("JACK")) {
		_connected = true;
	} else {
		_connected = false;
	}
}

void
Engine_TransportMaster::reset (bool)
{
	_starting = false;
}

bool
Engine_TransportMaster::locked() const
{
	return true;
}

bool
Engine_TransportMaster::ok() const
{
	return true;
}

void
Engine_TransportMaster::pre_process (pframes_t, samplepos_t, boost::optional<samplepos_t>)
{
	/* nothing to do */
}

bool
Engine_TransportMaster::speed_and_position (double& sp, samplepos_t& position, samplepos_t& lp, samplepos_t & when, samplepos_t now)
{
	boost::shared_ptr<AudioBackend> backend = engine.current_backend();

	/* 3rd argument (now) doesn't matter here because we're always being
	 * called synchronously with the engine.
	 */

	if (backend) {
		_starting = backend->speed_and_position (sp, position);
	} else {
		_starting = false;
	}

	lp = now;
	when = now;

	_current_delta = 0;

	return true;
}

std::string
Engine_TransportMaster::position_string () const
{
	if (_session) {
		return PBD::to_string (_session->audible_sample());
	}

	return std::string();
}

std::string
Engine_TransportMaster::delta_string () const
{
	return string ("0");
}

bool
Engine_TransportMaster::allow_request (TransportRequestSource src, TransportRequestType type) const
{
	if (_session) {
		if (_session->config.get_jack_time_master()) {
			return true;
		} else {
			return false;
		}
	}

	return true;
}

samplecnt_t
Engine_TransportMaster::update_interval () const
{
	return AudioEngine::instance()->samples_per_cycle();
}