// Copyright 2005-2020 The Mumble Developers. All rights reserved.
// Use of this source code is governed by a BSD-style license
// that can be found in the LICENSE file at the root of the
// Mumble source tree or at <https://www.mumble.info/LICENSE>.

#include "PulseAudio.h"

#include "MainWindow.h"
#include "Timer.h"
#include "User.h"

// We define a global macro called 'g'. This can lead to issues when included code uses 'g' as a type or parameter name (like protobuf 3.7 does). As such, for now, we have to make this our last include.
#include "Global.h"

static const char *mumble_sink_input = "Mumble Speakers";
static const char *mumble_echo = "Mumble Speakers (Echo)";

static PulseAudioSystem *pasys = NULL;

#define NBLOCKS 8

class PulseAudioInputRegistrar : public AudioInputRegistrar {
	public:
		PulseAudioInputRegistrar();
		virtual AudioInput *create();
		virtual const QList<audioDevice> getDeviceChoices();
		virtual void setDeviceChoice(const QVariant &, Settings &);
		virtual bool canEcho(const QString &) const;
};


class PulseAudioOutputRegistrar : public AudioOutputRegistrar {
	public:
		PulseAudioOutputRegistrar();
		virtual AudioOutput *create();
		virtual const QList<audioDevice> getDeviceChoices();
		virtual void setDeviceChoice(const QVariant &, Settings &);
		bool canMuteOthers() const;
};

class PulseAudioInit : public DeferInit {
	public:
		PulseAudioInputRegistrar *airPulseAudio;
		PulseAudioOutputRegistrar *aorPulseAudio;
		void initialize() {
			pasys = new PulseAudioSystem();
			pasys->qmWait.lock();
			pasys->qwcWait.wait(&pasys->qmWait, 1000);
			pasys->qmWait.unlock();
			if (pasys->bPulseIsGood) {
				airPulseAudio = new PulseAudioInputRegistrar();
				aorPulseAudio = new PulseAudioOutputRegistrar();
			} else {
				airPulseAudio = NULL;
				aorPulseAudio = NULL;
				delete pasys;
				pasys = NULL;
			}
		};
		void destroy() {
			delete airPulseAudio;
			delete aorPulseAudio;
			delete pasys;
			pasys = NULL;
		};
};

static PulseAudioInit pulseinit;

PulseAudioSystem::PulseAudioSystem() {
	pasInput = pasOutput = pasSpeaker = NULL;
	bSourceDone=bSinkDone=bServerDone = false;
	iDelayCache = 0;
	bPositionalCache = false;
	bAttenuating = false;
	iRemainingOperations = 0;
	bPulseIsGood = false;
	iSinkId = -1;

	pam = pa_threaded_mainloop_new();
	pa_mainloop_api *api = pa_threaded_mainloop_get_api(pam);

	pa_proplist *proplist;

	proplist = pa_proplist_new();
	pa_proplist_sets(proplist, PA_PROP_APPLICATION_NAME, "Mumble");
	pa_proplist_sets(proplist, PA_PROP_APPLICATION_ID, "net.sourceforge.mumble.mumble");
	pa_proplist_sets(proplist, PA_PROP_APPLICATION_ICON_NAME, "mumble");
	pa_proplist_sets(proplist, PA_PROP_MEDIA_ROLE, "game");

	pacContext = pa_context_new_with_proplist(api, NULL, proplist);
	pa_proplist_free(proplist);

	pa_context_set_subscribe_callback(pacContext, subscribe_callback, this);

	pa_context_set_state_callback(pacContext, context_state_callback, this);
	pa_context_connect(pacContext, NULL, PA_CONTEXT_NOAUTOSPAWN, NULL);

	pade = api->defer_new(api, defer_event_callback, this);
	api->defer_enable(pade, false);

	pa_threaded_mainloop_start(pam);

	bRunning = true;
}

PulseAudioSystem::~PulseAudioSystem() {
	bRunning = false;
	if (bAttenuating) {
		qmWait.lock();
		bAttenuating = false;
		setVolumes();
		bool success = qwcWait.wait(&qmWait, 1000);
		if (! success) {
			qWarning("PulseAudio: Shutdown timeout when attempting to restore volumes.");
		}
		qmWait.unlock();
	}
	pa_threaded_mainloop_stop(pam);
	pa_context_disconnect(pacContext);
	pa_context_unref(pacContext);
	pa_threaded_mainloop_free(pam);
}

QString PulseAudioSystem::outputDevice() const {
	QString odev = g.s.qsPulseAudioOutput;
	if (odev.isEmpty()) {
		odev = qsDefaultOutput;
	}
	if (!qhOutput.contains(odev)) {
		odev = qsDefaultOutput;
	}
	return odev;
}

QString PulseAudioSystem::inputDevice() const {
	QString idev = g.s.qsPulseAudioInput;
	if (idev.isEmpty()) {
		idev = qsDefaultInput;
	}
	if (!qhInput.contains(idev)) {
		idev = qsDefaultInput;
	}
	return idev;
}

void PulseAudioSystem::wakeup() {
	pa_mainloop_api *api = pa_threaded_mainloop_get_api(pam);
	api->defer_enable(pade, true);
}

void PulseAudioSystem::wakeup_lock() {
	pa_threaded_mainloop_lock(pam);
	pa_mainloop_api *api = pa_threaded_mainloop_get_api(pam);
	api->defer_enable(pade, true);
	pa_threaded_mainloop_unlock(pam);
}

void PulseAudioSystem::defer_event_callback(pa_mainloop_api *a, pa_defer_event *e, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	pas->eventCallback(a, e);
}

void PulseAudioSystem::eventCallback(pa_mainloop_api *api, pa_defer_event *) {
	api->defer_enable(pade, false);

	if (! bSourceDone || ! bSinkDone || ! bServerDone)
		return;

	AudioInputPtr ai = g.ai;
	AudioOutputPtr ao = g.ao;
	AudioInput *raw_ai = ai.get();
	AudioOutput *raw_ao = ao.get();
	PulseAudioInput *pai = dynamic_cast<PulseAudioInput *>(raw_ai);
	PulseAudioOutput *pao = dynamic_cast<PulseAudioOutput *>(raw_ao);

	if (raw_ao) {
		QString odev = outputDevice();
		pa_stream_state ost = pasOutput ? pa_stream_get_state(pasOutput) : PA_STREAM_TERMINATED;
		bool do_stop = false;
		bool do_start = false;

		if (! pao && (ost == PA_STREAM_READY)) {
			do_stop = true;
		} else if (pao) {
			switch (ost) {
				case PA_STREAM_TERMINATED: {
						if (pasOutput)
							pa_stream_unref(pasOutput);

						pa_sample_spec pss = qhSpecMap.value(odev);
						pa_channel_map pcm = qhChanMap.value(odev);
						if ((pss.format != PA_SAMPLE_FLOAT32NE) && (pss.format != PA_SAMPLE_S16NE))
							pss.format = PA_SAMPLE_FLOAT32NE;
						if (pss.rate == 0)
							pss.rate = SAMPLE_RATE;
						if ((pss.channels == 0) || (! g.s.doPositionalAudio()))
							pss.channels = 1;

						pasOutput = pa_stream_new(pacContext, mumble_sink_input, &pss, (pss.channels == 1) ? NULL : &pcm);
						pa_stream_set_state_callback(pasOutput, stream_callback, this);
						pa_stream_set_write_callback(pasOutput, write_callback, this);
					}
					// Fallthrough
				case PA_STREAM_UNCONNECTED:
					do_start = true;
					break;
				case PA_STREAM_READY: {
						if (g.s.iOutputDelay != iDelayCache) {
							do_stop = true;
						} else if (g.s.doPositionalAudio() != bPositionalCache) {
							do_stop = true;
						} else if (odev != qsOutputCache) {
							do_stop = true;
						}
						break;
					}
				default:
					break;
			}
		}
		if (do_stop) {
			qWarning("PulseAudio: Stopping output");
			pa_stream_disconnect(pasOutput);
			iSinkId = -1;
		} else if (do_start) {
			qWarning("PulseAudio: Starting output: %s", qPrintable(odev));
			pa_buffer_attr buff;
			const pa_sample_spec *pss = pa_stream_get_sample_spec(pasOutput);
			const size_t sampleSize = (pss->format == PA_SAMPLE_FLOAT32NE) ? sizeof(float) : sizeof(short);
			const unsigned int iBlockLen = ((pao->iFrameSize * pss->rate) / SAMPLE_RATE) * pss->channels * static_cast<unsigned int>(sampleSize);
			buff.tlength = iBlockLen * (g.s.iOutputDelay+1);
			buff.minreq = iBlockLen;
			buff.maxlength = -1;
			buff.prebuf = -1;
			buff.fragsize = iBlockLen;

			iDelayCache = g.s.iOutputDelay;
			bPositionalCache = g.s.doPositionalAudio();
			qsOutputCache = odev;

			pa_stream_connect_playback(pasOutput, qPrintable(odev), &buff, PA_STREAM_ADJUST_LATENCY, NULL, NULL);
			pa_context_get_sink_info_by_name(pacContext, qPrintable(odev), sink_info_callback, this);
		}
	}

	if (raw_ai) {
		QString idev = inputDevice();
		pa_stream_state ist = pasInput ? pa_stream_get_state(pasInput) : PA_STREAM_TERMINATED;
		bool do_stop = false;
		bool do_start = false;

		if (! pai && (ist == PA_STREAM_READY)) {
			do_stop = true;
		} else if (pai) {
			switch (ist) {
				case PA_STREAM_TERMINATED: {
						if (pasInput)
							pa_stream_unref(pasInput);

						pa_sample_spec pss = qhSpecMap.value(idev);
						if ((pss.format != PA_SAMPLE_FLOAT32NE) && (pss.format != PA_SAMPLE_S16NE))
							pss.format = PA_SAMPLE_FLOAT32NE;
						if (pss.rate == 0)
							pss.rate = SAMPLE_RATE;
						pss.channels = 1;

						pasInput = pa_stream_new(pacContext, "Microphone", &pss, NULL);
						pa_stream_set_state_callback(pasInput, stream_callback, this);
						pa_stream_set_read_callback(pasInput, read_callback, this);
					}
					// Fallthrough
				case PA_STREAM_UNCONNECTED:
					do_start = true;
					break;
				case PA_STREAM_READY: {
						if (idev != qsInputCache) {
							do_stop = true;
						}
						break;
					}
				default:
					break;
			}
		}
		if (do_stop) {
			qWarning("PulseAudio: Stopping input");
			pa_stream_disconnect(pasInput);
		} else if (do_start) {
			qWarning("PulseAudio: Starting input %s",qPrintable(idev));
			pa_buffer_attr buff;
			const pa_sample_spec *pss = pa_stream_get_sample_spec(pasInput);
			const size_t sampleSize = (pss->format == PA_SAMPLE_FLOAT32NE) ? sizeof(float) : sizeof(short);
			const unsigned int iBlockLen = ((pai->iFrameSize * pss->rate) / SAMPLE_RATE) * pss->channels * static_cast<unsigned int>(sampleSize);
			buff.tlength = iBlockLen;
			buff.minreq = iBlockLen;
			buff.maxlength = -1;
			buff.prebuf = -1;
			buff.fragsize = iBlockLen;

			qsInputCache = idev;

			pa_stream_connect_record(pasInput, qPrintable(idev), &buff, PA_STREAM_ADJUST_LATENCY);

			// Ensure stream is initially un-muted
			pa_stream_cork(pasInput, 0, NULL, NULL);

			connect(g.mw, &MainWindow::corkAudioInputStream, this, &PulseAudioSystem::corkAudioInputStream);
		}
	}

	if (raw_ai) {
		QString odev = outputDevice();
		QString edev = qhEchoMap.value(odev);
		pa_stream_state est = pasSpeaker ? pa_stream_get_state(pasSpeaker) : PA_STREAM_TERMINATED;
		bool do_stop = false;
		bool do_start = false;

		if ((! pai || ! g.s.doEcho()) && (est == PA_STREAM_READY)) {
			do_stop = true;
		} else if (pai && g.s.doEcho()) {
			switch (est) {
				case PA_STREAM_TERMINATED: {
						if (pasSpeaker)
							pa_stream_unref(pasSpeaker);

						pa_sample_spec pss = qhSpecMap.value(edev);
						pa_channel_map pcm = qhChanMap.value(edev);
						if ((pss.format != PA_SAMPLE_FLOAT32NE) && (pss.format != PA_SAMPLE_S16NE))
							pss.format = PA_SAMPLE_FLOAT32NE;
						if (pss.rate == 0)
							pss.rate = SAMPLE_RATE;
						if ((pss.channels == 0) || (! g.s.bEchoMulti))
							pss.channels = 1;

						pasSpeaker = pa_stream_new(pacContext, mumble_echo, &pss, (pss.channels == 1) ? NULL : &pcm);
						pa_stream_set_state_callback(pasSpeaker, stream_callback, this);
						pa_stream_set_read_callback(pasSpeaker, read_callback, this);
					}
					// Fallthrough
				case PA_STREAM_UNCONNECTED:
					do_start = true;
					break;
				case PA_STREAM_READY: {
						if (g.s.bEchoMulti != bEchoMultiCache) {
							do_stop = true;
						} else if (edev != qsEchoCache) {
							do_stop = true;
						}
						break;
					}
				default:
					break;
			}
		}
		if (do_stop) {
			qWarning("PulseAudio: Stopping echo");
			pa_stream_disconnect(pasSpeaker);
		} else if (do_start) {
			qWarning("PulseAudio: Starting echo: %s", qPrintable(edev));
			pa_buffer_attr buff;
			const pa_sample_spec *pss = pa_stream_get_sample_spec(pasSpeaker);
			const size_t sampleSize = (pss->format == PA_SAMPLE_FLOAT32NE) ? sizeof(float) : sizeof(short);
			const unsigned int iBlockLen = ((pai->iFrameSize * pss->rate) / SAMPLE_RATE) * pss->channels * static_cast<unsigned int>(sampleSize);
			buff.tlength = iBlockLen;
			buff.minreq = iBlockLen;
			buff.maxlength = -1;
			buff.prebuf = -1;
			buff.fragsize = iBlockLen;

			bEchoMultiCache = g.s.bEchoMulti;
			qsEchoCache = edev;

			pa_stream_connect_record(pasSpeaker, qPrintable(edev), &buff, PA_STREAM_ADJUST_LATENCY);
		}
	}
}

void PulseAudioSystem::corkAudioInputStream(const bool cork)
{
	if (pasInput) {
		pa_threaded_mainloop_lock(pam);
		pa_stream_cork(pasInput, cork, nullptr, nullptr);
		pa_threaded_mainloop_unlock(pam);
	}
}

void PulseAudioSystem::context_state_callback(pa_context *c, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	pas->contextCallback(c);
}

void PulseAudioSystem::subscribe_callback(pa_context *, pa_subscription_event_type evt, unsigned int, void *userdata) {
	switch (evt & PA_SUBSCRIPTION_EVENT_TYPE_MASK) {
		case PA_SUBSCRIPTION_EVENT_NEW:
		case PA_SUBSCRIPTION_EVENT_REMOVE:
			break;
		default:
			return;
	}
	switch (evt & PA_SUBSCRIPTION_EVENT_FACILITY_MASK) {
		case PA_SUBSCRIPTION_EVENT_SINK:
		case PA_SUBSCRIPTION_EVENT_SOURCE:
			break;
		default:
			return;
	}
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	qWarning("PulseAudio: Sinks or inputs changed (inserted or removed sound card)");
	pas->query();
}

void PulseAudioSystem::sink_callback(pa_context *, const pa_sink_info *i, int eol, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	if (!i || eol) {
		pas->bSinkDone = true;
		pas->wakeup();
		return;
	}

	const QString name = QString::fromUtf8(i->name);

	pas->qhSpecMap.insert(name, i->sample_spec);
	pas->qhChanMap.insert(name, i->channel_map);
	pas->qhOutput.insert(name, QString::fromUtf8(i->description));
	pas->qhEchoMap.insert(name, QString::fromUtf8(i->monitor_source_name));
}

void PulseAudioSystem::source_callback(pa_context *, const pa_source_info *i, int eol, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	if (!i || eol) {
		pas->bSourceDone = true;
		pas->wakeup();
		return;
	}

	const QString name = QString::fromUtf8(i->name);

	pas->qhSpecMap.insert(name, i->sample_spec);
	pas->qhChanMap.insert(name, i->channel_map);

	pas->qhInput.insert(QString::fromUtf8(i->name), QString::fromUtf8(i->description));
}

void PulseAudioSystem::server_callback(pa_context *, const pa_server_info *i, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);

	pas->qsDefaultInput = QString::fromUtf8(i->default_source_name);
	pas->qsDefaultOutput = QString::fromUtf8(i->default_sink_name);

	pas->bServerDone = true;
	pas->wakeup();
}

void PulseAudioSystem::sink_info_callback(pa_context *, const pa_sink_info *i, int eol, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	if (!i || eol) {
		return;
	}

	pas->iSinkId = i->index;
}


void PulseAudioSystem::stream_callback(pa_stream *s, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	switch (pa_stream_get_state(s)) {
		case PA_STREAM_FAILED:
			qWarning("PulseAudio: Stream error: %s", pa_strerror(pa_context_errno(pa_stream_get_context(s))));
			break;
		default:
			break;
	}
	pas->wakeup();
}

void PulseAudioSystem::read_callback(pa_stream *s, size_t bytes, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);

	size_t length = bytes;
	const void *data = NULL;
	pa_stream_peek(s, &data, &length);
	if (data == NULL && length > 0) {
		qWarning("PulseAudio: pa_stream_peek reports no data at current read index.");
	} else if (data == NULL && length == 0) {
		qWarning("PulseAudio: pa_stream_peek reports empty memblockq.");
	} else if (data == NULL || length == 0) {
		qWarning("PulseAudio: invalid pa_stream_peek state encountered.");
		return;
	}

	AudioInputPtr ai = g.ai;
	PulseAudioInput *pai = dynamic_cast<PulseAudioInput *>(ai.get());
	if (! pai) {
		if (length > 0) {
			pa_stream_drop(s);
		}
		pas->wakeup();
		return;
	}

	const pa_sample_spec *pss = pa_stream_get_sample_spec(s);

	if (s == pas->pasInput) {
		if (!pa_sample_spec_equal(pss, &pai->pssMic)) {
			pai->pssMic = *pss;
			pai->iMicFreq = pss->rate;
			pai->iMicChannels = pss->channels;
			if (pss->format == PA_SAMPLE_FLOAT32NE)
				pai->eMicFormat = PulseAudioInput::SampleFloat;
			else
				pai->eMicFormat = PulseAudioInput::SampleShort;
			pai->initializeMixer();
		}
		if (data != NULL) {
			pai->addMic(data, static_cast<unsigned int>(length) / pai->iMicSampleSize);
		}
	} else if (s == pas->pasSpeaker) {
		if (!pa_sample_spec_equal(pss, &pai->pssEcho)) {
			pai->pssEcho = *pss;
			pai->iEchoFreq = pss->rate;
			pai->iEchoChannels = pss->channels;
			if (pss->format == PA_SAMPLE_FLOAT32NE)
				pai->eEchoFormat = PulseAudioInput::SampleFloat;
			else
				pai->eEchoFormat = PulseAudioInput::SampleShort;
			pai->initializeMixer();
		}
		if (data != NULL) {
			pai->addEcho(data, static_cast<unsigned int>(length) / pai->iEchoSampleSize);
		}
	}

	if (length > 0) {
		pa_stream_drop(s);
	}
}

void PulseAudioSystem::write_callback(pa_stream *s, size_t bytes, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);
	Q_ASSERT(s == pas->pasOutput);

	AudioOutputPtr ao = g.ao;
	PulseAudioOutput *pao = dynamic_cast<PulseAudioOutput *>(ao.get());

	if (! pao) {
		return;
	}

	const pa_sample_spec *pss = pa_stream_get_sample_spec(s);
	const pa_channel_map *pcm = pa_stream_get_channel_map(pas->pasOutput);
	if (!pa_sample_spec_equal(pss, &pao->pss) || !pa_channel_map_equal(pcm, &pao->pcm)) {
		pao->pss = *pss;
		pao->pcm = *pcm;
		if (pss->format == PA_SAMPLE_FLOAT32NE)
			pao->eSampleFormat = PulseAudioOutput::SampleFloat;
		else
			pao->eSampleFormat = PulseAudioOutput::SampleShort;
		pao->iMixerFreq = pss->rate;
		pao->iChannels = pss->channels;
		unsigned int chanmasks[pss->channels];
		for (int i=0;i<pss->channels;++i) {
			unsigned int cm = 0;
			switch (pcm->map[i]) {
				case PA_CHANNEL_POSITION_LEFT:
					cm = SPEAKER_FRONT_LEFT;
					break;
				case PA_CHANNEL_POSITION_RIGHT:
					cm = SPEAKER_FRONT_RIGHT;
					break;
				case PA_CHANNEL_POSITION_CENTER:
					cm = SPEAKER_FRONT_CENTER;
					break;
				case PA_CHANNEL_POSITION_REAR_LEFT:
					cm = SPEAKER_BACK_LEFT;
					break;
				case PA_CHANNEL_POSITION_REAR_RIGHT:
					cm = SPEAKER_BACK_RIGHT;
					break;
				case PA_CHANNEL_POSITION_REAR_CENTER:
					cm = SPEAKER_BACK_CENTER;
					break;
				case PA_CHANNEL_POSITION_LFE:
					cm = SPEAKER_LOW_FREQUENCY;
					break;
				case PA_CHANNEL_POSITION_SIDE_LEFT:
					cm = SPEAKER_SIDE_LEFT;
					break;
				case PA_CHANNEL_POSITION_SIDE_RIGHT:
					cm = SPEAKER_SIDE_RIGHT;
					break;
				case PA_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER:
					cm = SPEAKER_FRONT_LEFT_OF_CENTER;
					break;
				case PA_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER:
					cm = SPEAKER_FRONT_RIGHT_OF_CENTER;
					break;
				default:
					cm = 0;
					break;
			}
			chanmasks[i] = cm;
		}
		pao->initializeMixer(chanmasks);
	}

	const unsigned int iSampleSize = pao->iSampleSize;
	const unsigned int samples = static_cast<unsigned int>(bytes) / iSampleSize;
	bool oldAttenuation = pas->bAttenuating;

	unsigned char buffer[bytes];
	// do we have some mixed output?
	if (pao->mix(buffer, samples)) {
		// attenuate if instructed to or it's in settings
		pas->bAttenuating = (g.bAttenuateOthers || g.s.bAttenuateOthers);

	} else {
		memset(buffer, 0, bytes);

		// attenuate if intructed to (self-activated)
		pas->bAttenuating = g.bAttenuateOthers;
	}

	// if the attenuation state has changed
	if (oldAttenuation != pas->bAttenuating) {
		pas->setVolumes();
	}

	pa_stream_write(s, buffer, iSampleSize * samples, NULL, 0, PA_SEEK_RELATIVE);
}

void PulseAudioSystem::volume_sink_input_list_callback(pa_context *c, const pa_sink_input_info *i, int eol, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);

	if (eol == 0) {
		// If we're using the default of "enable attenuation on all ouputs" and output from an application is loopbacked,
		// both the loopback and the application will be attenuated leading to double attenuation.
		if (!g.s.bOnlyAttenuateSameOutput && pas->iSinkId > -1 && !strcmp(i->driver, "module-loopback.c")) {
			return;
		}
		// If we're not attenuating different sinks and the input is not on this sink, don't attenuate. Or,
		// if the input is a loopback module and connected to Mumble's sink, also ignore it (loopbacks are used to connect
		// sinks). An attenuated loopback means an indirect application attenuation.
		if (g.s.bOnlyAttenuateSameOutput && pas->iSinkId > -1) {
			if (int(i->sink) != pas->iSinkId || (int(i->sink) == pas->iSinkId && !strcmp(i->driver, "module-loopback.c") && !g.s.bAttenuateLoopbacks)) {
				return;
			}
		}
		// ensure we're not attenuating ourselves!
		if (strcmp(i->name, mumble_sink_input) != 0) {
			// create a new entry
			PulseAttenuation patt;
			patt.index = i->index;
			patt.name = QString::fromUtf8(i->name);
			patt.stream_restore_id = QString::fromUtf8(pa_proplist_gets(i->proplist, "module-stream-restore.id"));
			patt.normal_volume = i->volume;

			// calculate the attenuated volume
			pa_volume_t adj = static_cast<pa_volume_t>(PA_VOLUME_NORM * g.s.fOtherVolume);
			pa_sw_cvolume_multiply_scalar(&patt.attenuated_volume, &i->volume, adj);

			// set it on the sink input
			pa_operation_unref(pa_context_set_sink_input_volume(c, i->index, &patt.attenuated_volume, NULL, NULL));

			// store it
			pas->qhVolumes[i->index] = patt;
		}

	} else if (eol < 0) {
		qWarning("PulseAudio: Sink input introspection error.");
	}
}

void PulseAudioSystem::restore_sink_input_list_callback(pa_context *c, const pa_sink_input_info *i, int eol, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);

	if (eol == 0) {
		// if we were tracking this specific sink previously
		if (pas->qhVolumes.contains(i->index)) {
			// and if it has the attenuated volume we applied to it
			if (pa_cvolume_equal(&i->volume, &pas->qhVolumes[i->index].attenuated_volume) != 0) {
				// mark it as matched
				pas->qlMatchedSinks.append(i->index);

				// reset the volume to normal
				pas->iRemainingOperations++;
				pa_operation_unref(pa_context_set_sink_input_volume(c, i->index, &pas->qhVolumes[i->index].normal_volume, restore_volume_success_callback, pas));
			}

		// otherwise, save for matching at the end of iteration
		} else {
			QString restore_id = QString::fromUtf8(pa_proplist_gets(i->proplist, "module-stream-restore.id"));
			PulseAttenuation patt;
			patt.index = i->index;
			patt.normal_volume = i->volume;
			pas->qhUnmatchedSinks[restore_id] = patt;
		}

	} else if (eol < 0) {
		qWarning("PulseAudio: Sink input introspection error.");

	} else {
		// build a list of missing streams by iterating our active list
		QHash<uint32_t, PulseAttenuation>::const_iterator it;
		for (it = pas->qhVolumes.constBegin(); it != pas->qhVolumes.constEnd(); ++it) {
			// skip if previously matched
			if (pas->qlMatchedSinks.contains(it.key())) {
				continue;
			}

			// check if the restore id matches. the only case where this would
			// happen is if the application was reopened during attenuation.
			if (pas->qhUnmatchedSinks.contains(it.value().stream_restore_id)) {
				PulseAttenuation active_sink = pas->qhUnmatchedSinks[it.value().stream_restore_id];
				// if the volume wasn't changed from our attenuation
				if (pa_cvolume_equal(&active_sink.normal_volume, &it.value().attenuated_volume) != 0) {
					// reset the volume to normal
					pas->iRemainingOperations++;
					pa_operation_unref(pa_context_set_sink_input_volume(c, active_sink.index, &it.value().normal_volume, restore_volume_success_callback, pas));
				}
				continue;
			}

			// at this point, we don't know what happened to the sink. add
			// it to a list to check the stream restore database for.
			pas->qhMissingSinks[it.value().stream_restore_id] = it.value();
		}

		// clean up
		pas->qlMatchedSinks.clear();
		pas->qhUnmatchedSinks.clear();
		pas->qhVolumes.clear();

		// if we had missing sinks, check the stream restore database
		// to see if we can find and update them.
		if (pas->qhMissingSinks.count() > 0) {
			pas->iRemainingOperations++;
			pa_operation_unref(pa_ext_stream_restore_read(c, stream_restore_read_callback, pas));
		}

		// trigger the volume completion callback;
		// necessary so that shutdown actions are called
		restore_volume_success_callback(c, 1, pas);
	}
}

void PulseAudioSystem::stream_restore_read_callback(pa_context *c, const pa_ext_stream_restore_info *i, int eol, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);

	if (eol == 0) {
		QString name = QString::fromUtf8(i->name);

		// were we looking for this restoration?
		if (pas->qhMissingSinks.contains(name)) {
			// make sure it still has the volume we gave it
			if (pa_cvolume_equal(&pas->qhMissingSinks[name].attenuated_volume, &i->volume) != 0) {
				// update the stream restore record
				pa_ext_stream_restore_info restore = *i;
				restore.volume = pas->qhMissingSinks[name].normal_volume;
				pas->iRemainingOperations++;
				pa_operation_unref(pa_ext_stream_restore_write(c, PA_UPDATE_REPLACE, &restore, 1, 1, restore_volume_success_callback, pas));
			}

			pas->qhMissingSinks.remove(name);
		}

	} else if (eol < 0) {
		qWarning("PulseAudio: Couldn't read stream restore database.");
		pas->qhMissingSinks.clear();

	} else {
		// verify missing list is empty
		if (pas->qhMissingSinks.count() > 0) {
			qWarning("PulseAudio: Failed to match %d stream(s).", pas->qhMissingSinks.count());
			pas->qhMissingSinks.clear();
		}

		// trigger the volume completion callback;
		// necessary so that shutdown actions are called
		restore_volume_success_callback(c, 1, pas);
	}
}

void PulseAudioSystem::restore_volume_success_callback(pa_context *, int, void *userdata) {
	PulseAudioSystem *pas = reinterpret_cast<PulseAudioSystem *>(userdata);

	pas->iRemainingOperations--;

	// if there are no more pending volume adjustments and we're shutting down,
	// let the main thread know
	if (! pas->bRunning && pas->iRemainingOperations == 0) {
		pas->qwcWait.wakeAll();
	}
}

void PulseAudioSystem::query() {
	bSourceDone=bSinkDone=bServerDone = false;
	qhInput.clear();
	qhOutput.clear();
	qhEchoMap.clear();
	qhSpecMap.clear();
	qhChanMap.clear();
	qhInput.insert(QString(), tr("Default Input"));
	qhOutput.insert(QString(), tr("Default Output"));
	pa_operation_unref(pa_context_get_server_info(pacContext, server_callback, this));
	pa_operation_unref(pa_context_get_sink_info_list(pacContext, sink_callback, this));
	pa_operation_unref(pa_context_get_source_info_list(pacContext, source_callback, this));
	wakeup();
}

void PulseAudioSystem::setVolumes() {
	// set attenuation state and volumes
	if (bAttenuating) {
		// ensure the volume map is empty, otherwise it may be dangerous to change
		if (qhVolumes.empty()) {
			// set the new per-application volumes and store the old ones
			pa_operation_unref(pa_context_get_sink_input_info_list(pacContext, volume_sink_input_list_callback, this));
		}
	// clear attenuation state and restore normal volumes
	} else {
		iRemainingOperations++;
		pa_operation_unref(pa_context_get_sink_input_info_list(pacContext, restore_sink_input_list_callback, this));
	}
}

void PulseAudioSystem::contextCallback(pa_context *c) {
	Q_ASSERT(c == pacContext);
	switch (pa_context_get_state(c)) {
		case PA_CONTEXT_READY:
			bPulseIsGood = true;
			pa_operation_unref(pa_context_subscribe(pacContext, PA_SUBSCRIPTION_MASK_SOURCE, NULL, this));
			pa_operation_unref(pa_context_subscribe(pacContext, PA_SUBSCRIPTION_MASK_SINK, NULL, this));
			query();
			break;
		case PA_CONTEXT_TERMINATED:
			qWarning("PulseAudio: Forcibly disconnected from PulseAudio");
			break;
		case PA_CONTEXT_FAILED:
			qWarning("PulseAudio: Connection failure: %s", pa_strerror(pa_context_errno(c)));
			break;
		default:
			return;
	}
	qmWait.lock();
	qwcWait.wakeAll();
	qmWait.unlock();
}

PulseAudioInputRegistrar::PulseAudioInputRegistrar() : AudioInputRegistrar(QLatin1String("PulseAudio"), 10) {
}

AudioInput *PulseAudioInputRegistrar::create() {
	return new PulseAudioInput();
}

const QList<audioDevice> PulseAudioInputRegistrar::getDeviceChoices() {
	QList<audioDevice> qlReturn;

	QStringList qlInputDevs = pasys->qhInput.keys();
	std::sort(qlInputDevs.begin(), qlInputDevs.end());

	if (qlInputDevs.contains(g.s.qsPulseAudioInput)) {
		qlInputDevs.removeAll(g.s.qsPulseAudioInput);
		qlInputDevs.prepend(g.s.qsPulseAudioInput);
	}

	foreach(const QString &dev, qlInputDevs) {
		qlReturn << audioDevice(pasys->qhInput.value(dev), dev);
	}

	return qlReturn;
}

void PulseAudioInputRegistrar::setDeviceChoice(const QVariant &choice, Settings &s) {
	s.qsPulseAudioInput = choice.toString();
}

bool PulseAudioInputRegistrar::canEcho(const QString &osys) const {
	return (osys == name);
}

PulseAudioOutputRegistrar::PulseAudioOutputRegistrar() : AudioOutputRegistrar(QLatin1String("PulseAudio"), 10) {
}

AudioOutput *PulseAudioOutputRegistrar::create() {
	return new PulseAudioOutput();
}

const QList<audioDevice> PulseAudioOutputRegistrar::getDeviceChoices() {
	QList<audioDevice> qlReturn;

	QStringList qlOutputDevs = pasys->qhOutput.keys();
	std::sort(qlOutputDevs.begin(), qlOutputDevs.end());

	if (qlOutputDevs.contains(g.s.qsPulseAudioOutput)) {
		qlOutputDevs.removeAll(g.s.qsPulseAudioOutput);
		qlOutputDevs.prepend(g.s.qsPulseAudioOutput);
	}

	foreach(const QString &dev, qlOutputDevs) {
		qlReturn << audioDevice(pasys->qhOutput.value(dev), dev);
	}

	return qlReturn;
}

void PulseAudioOutputRegistrar::setDeviceChoice(const QVariant &choice, Settings &s) {
	s.qsPulseAudioOutput = choice.toString();
}

bool PulseAudioOutputRegistrar::canMuteOthers() const {
	return true;
}

PulseAudioInput::PulseAudioInput() {
	memset(&pssMic, 0, sizeof(pssMic));
	memset(&pssEcho, 0, sizeof(pssEcho));
	bRunning = true;
	if (pasys)
		pasys->wakeup_lock();
}

PulseAudioInput::~PulseAudioInput() {
	bRunning = false;
	qmMutex.lock();
	qwcWait.wakeAll();
	qmMutex.unlock();
	wait();
	if (pasys)
		pasys->wakeup_lock();
}

void PulseAudioInput::run() {
	qmMutex.lock();
	while (bRunning)
		qwcWait.wait(&qmMutex);
	qmMutex.unlock();
}

PulseAudioOutput::PulseAudioOutput() {
	memset(&pss, 0, sizeof(pss));
	memset(&pcm, 0, sizeof(pcm));
	bRunning = true;
	if (pasys)
		pasys->wakeup_lock();
}

PulseAudioOutput::~PulseAudioOutput() {
	bRunning = false;
	qmMutex.lock();
	qwcWait.wakeAll();
	qmMutex.unlock();
	wait();
	if (pasys)
		pasys->wakeup_lock();
}

void PulseAudioOutput::run() {
	qmMutex.lock();
	while (bRunning)
		qwcWait.wait(&qmMutex);
	qmMutex.unlock();
}