//
// libtgvoip is free and unencumbered public domain software.
// For more information, see http://unlicense.org or the UNLICENSE file
// you should have received with this source code distribution.
//

#include "controller/audio/OpusEncoder.h"
#include <assert.h>
#include <algorithm>
#include "tools/logging.h"
#include "VoIPServerConfig.h"
#if defined HAVE_CONFIG_H || defined TGVOIP_USE_INSTALLED_OPUS
#include <opus/opus.h>
#else
#include <opus/opus.h>
#endif

namespace
{
inline int serverConfigValueToBandwidth(int config)
{
	switch (config)
	{
	case 0:
		return OPUS_BANDWIDTH_NARROWBAND;
	case 1:
		return OPUS_BANDWIDTH_MEDIUMBAND;
	case 2:
		return OPUS_BANDWIDTH_WIDEBAND;
	case 3:
		return OPUS_BANDWIDTH_SUPERWIDEBAND;
	case 4:
	default:
		return OPUS_BANDWIDTH_FULLBAND;
	}
}
} // namespace

tgvoip::OpusEncoder::OpusEncoder(const std::shared_ptr<MediaStreamItf> &source, bool needSecondary) : queue(10)
{
	this->source = source;
	source->SetCallback(tgvoip::OpusEncoder::Callback, this);
	
	enc = opus_encoder_create(48000, 1, OPUS_APPLICATION_VOIP, NULL);
	opus_encoder_ctl(enc, OPUS_SET_COMPLEXITY(10));
	opus_encoder_ctl(enc, OPUS_SET_PACKET_LOSS_PERC(1));
	opus_encoder_ctl(enc, OPUS_SET_INBAND_FEC(1));
	opus_encoder_ctl(enc, OPUS_SET_SIGNAL(OPUS_SIGNAL_VOICE));
	opus_encoder_ctl(enc, OPUS_SET_BANDWIDTH(OPUS_AUTO));
	requestedBitrate = 20000;
	currentBitrate = 0;
	running = false;
	echoCanceller = NULL;
	complexity = 10;
	frameDuration = 20;
	levelMeter = NULL;
	vadNoVoiceBitrate = static_cast<uint32_t>(ServerConfig::GetSharedInstance()->GetInt("audio_vad_no_voice_bitrate", 6000));
	vadModeVoiceBandwidth = serverConfigValueToBandwidth(ServerConfig::GetSharedInstance()->GetInt("audio_vad_bandwidth", 3));
	vadModeNoVoiceBandwidth = serverConfigValueToBandwidth(ServerConfig::GetSharedInstance()->GetInt("audio_vad_no_voice_bandwidth", 0));
	secondaryEnabledBandwidth = serverConfigValueToBandwidth(ServerConfig::GetSharedInstance()->GetInt("audio_extra_ec_bandwidth", 2));
	secondaryEncoderEnabled = false;

	currentSecondaryBitrate = 8000;
	if (needSecondary)
	{
		secondaryEncoder = opus_encoder_create(48000, 1, OPUS_APPLICATION_VOIP, NULL);
		opus_encoder_ctl(secondaryEncoder, OPUS_SET_COMPLEXITY(10));
		opus_encoder_ctl(secondaryEncoder, OPUS_SET_SIGNAL(OPUS_SIGNAL_VOICE));
		opus_encoder_ctl(secondaryEncoder, OPUS_SET_BITRATE(currentSecondaryBitrate));
	}
	else
	{
		secondaryEncoder = NULL;
	}
}

tgvoip::OpusEncoder::~OpusEncoder()
{
	Stop();
	opus_encoder_destroy(enc);
	if (secondaryEncoder)
		opus_encoder_destroy(secondaryEncoder);
}

void tgvoip::OpusEncoder::Start()
{
	if (running)
		return;
	running = true;
	thread = new Thread(std::bind(&tgvoip::OpusEncoder::RunThread, this));
	thread->SetName("OpusEncoder");
	thread->SetMaxPriority();
	thread->Start();
}

void tgvoip::OpusEncoder::Stop()
{
	if (!running)
		return;
	running = false;
	queue.Put(Buffer());
	thread->Join();
	delete thread;
}

void tgvoip::OpusEncoder::SetBitrate(uint32_t bitrate)
{
	requestedBitrate = bitrate;
}

void tgvoip::OpusEncoder::Encode(int16_t *data, size_t len)
{
	if (requestedBitrate != currentBitrate)
	{
		opus_encoder_ctl(enc, OPUS_SET_BITRATE(requestedBitrate));
		currentBitrate = requestedBitrate;
		LOGV("opus_encoder: setting bitrate to %u", currentBitrate);
	}
	if (levelMeter)
		levelMeter->Update(data, len);
	if (secondaryEncoderEnabled != wasSecondaryEncoderEnabled)
	{
		wasSecondaryEncoderEnabled = secondaryEncoderEnabled;
	}
	int32_t r = opus_encode(enc, data, static_cast<int>(len), buffer, 4096);
	//	int bw;
	//	opus_encoder_ctl(enc, OPUS_GET_BANDWIDTH(&bw));
	//	LOGV("Opus bandwidth: %d", bw);
	if (r <= 0)
	{
		LOGE("Error encoding: %d", r);
	}
	else if (r == 1)
	{
		LOGW("DTX");
	}
	else if (running)
	{
		//LOGV("Packet size = %d", r);
		int32_t secondaryLen = 0;
		unsigned char secondaryBuffer[128];
		if (secondaryEncoderEnabled && secondaryEncoder)
		{
			secondaryLen = opus_encode(secondaryEncoder, data, static_cast<int>(len), secondaryBuffer, sizeof(secondaryBuffer));
			//LOGV("secondaryLen %d", secondaryLen);
		}
		InvokeCallback(buffer, (size_t)r, secondaryBuffer, (size_t)secondaryLen);
	}
}

size_t tgvoip::OpusEncoder::Callback(unsigned char *data, size_t len, void *param)
{
	assert(len == 960 * 2);
	OpusEncoder *e = (OpusEncoder *)param;
	try
	{
		Buffer buf = e->bufferPool.Get();
		buf.CopyFrom(data, 0, 960 * 2);
		e->queue.Put(std::move(buf));
	}
	catch (std::bad_alloc &x)
	{
		LOGW("opus_encoder: no buffer slots left");
		if (e->complexity > 1)
		{
			e->complexity--;
			opus_encoder_ctl(e->enc, OPUS_SET_COMPLEXITY(e->complexity));
		}
	}
	return 0;
}

uint32_t tgvoip::OpusEncoder::GetBitrate()
{
	return requestedBitrate;
}

void tgvoip::OpusEncoder::SetEchoCanceller(const std::shared_ptr<EchoCanceller> &aec)
{
	echoCanceller = aec;
}

void tgvoip::OpusEncoder::RunThread()
{
	uint32_t bufferedCount = 0;
	uint32_t packetsPerFrame = frameDuration / 20;
	LOGV("starting encoder, packets per frame=%d", packetsPerFrame);
	int16_t *frame;
	if (packetsPerFrame > 1)
		frame = reinterpret_cast<int16_t *>(std::malloc(960 * 2 * packetsPerFrame));
	else
		frame = NULL;
	bool frameHasVoice = false;
	bool wasVadMode = false;
	while (running)
	{
		Buffer _packet = queue.GetBlocking();
		if (!_packet.IsEmpty())
		{
			int16_t *packet = reinterpret_cast<int16_t *>(*_packet);
			bool hasVoice = true;
			if (echoCanceller)
				echoCanceller->ProcessInput(packet, 960, hasVoice);
			if (!postProcEffects.empty())
			{
				for (auto &effect : postProcEffects)
				{
					effect->Process(packet, 960);
				}
			}
			if (packetsPerFrame == 1)
			{
				Encode(packet, 960);
			}
			else
			{
				memcpy(frame + (960 * bufferedCount), packet, 960 * 2); // Accumulate raw frames
				frameHasVoice = frameHasVoice || hasVoice;
				bufferedCount++;
				if (bufferedCount == packetsPerFrame)
				{
					if (vadMode)
					{
						if (frameHasVoice)
						{
							opus_encoder_ctl(enc, OPUS_SET_BITRATE(currentBitrate));
							if (secondaryEncoder)
							{
								opus_encoder_ctl(secondaryEncoder, OPUS_SET_BITRATE(currentSecondaryBitrate));
							}
						}
						else
						{
							opus_encoder_ctl(enc, OPUS_SET_BITRATE(vadNoVoiceBitrate));
							if (secondaryEncoder)
							{
								opus_encoder_ctl(secondaryEncoder, OPUS_SET_BITRATE(vadNoVoiceBitrate));
							}
						}
						wasVadMode = true;
					}
					else if (wasVadMode)
					{
						wasVadMode = false;
						opus_encoder_ctl(enc, OPUS_SET_BITRATE(currentBitrate));
						if (secondaryEncoder)
						{
							opus_encoder_ctl(secondaryEncoder, OPUS_SET_BITRATE(currentSecondaryBitrate));
						}
					}
					Encode(frame, 960 * packetsPerFrame);
					bufferedCount = 0;
					frameHasVoice = false;
				}
			}
		}
		else
		{
			break;
		}
	}
	if (frame)
		free(frame);
}

void tgvoip::OpusEncoder::SetOutputFrameDuration(uint32_t duration)
{
	frameDuration = duration;
}

void tgvoip::OpusEncoder::SetPacketLoss(int percent)
{
	packetLossPercent = std::min(20, percent);
	opus_encoder_ctl(enc, OPUS_SET_PACKET_LOSS_PERC(packetLossPercent));
	opus_encoder_ctl(enc, OPUS_SET_INBAND_FEC(percent > 0 && !secondaryEncoderEnabled ? 1 : 0));
}

int tgvoip::OpusEncoder::GetPacketLoss()
{
	return packetLossPercent;
}

void tgvoip::OpusEncoder::SetDTX(bool enable)
{
	opus_encoder_ctl(enc, OPUS_SET_DTX(enable ? 1 : 0));
}

void tgvoip::OpusEncoder::SetLevelMeter(const std::shared_ptr<tgvoip::AudioLevelMeter> &levelMeter)
{
	this->levelMeter = levelMeter;
}

void tgvoip::OpusEncoder::SetCallback(std::function<void(unsigned char *, size_t, unsigned char *, size_t)> f)
{
	callback = f;
}

void tgvoip::OpusEncoder::InvokeCallback(unsigned char *data, size_t length, unsigned char *secondaryData, size_t secondaryLength)
{
	callback(data, length, secondaryData, secondaryLength);
}

void tgvoip::OpusEncoder::SetSecondaryEncoderEnabled(bool enabled)
{
	secondaryEncoderEnabled = enabled;
}

void tgvoip::OpusEncoder::SetVadMode(bool vad)
{
	vadMode = vad;
}



void tgvoip::OpusEncoder::AddAudioEffect(const std::shared_ptr<effects::AudioEffect> &effect)
{
	postProcEffects.push_back(effect);
}

void tgvoip::OpusEncoder::RemoveAudioEffect(const std::shared_ptr<effects::AudioEffect> &effect)
{
	auto i = std::find(postProcEffects.begin(), postProcEffects.end(), effect);
	if (i != postProcEffects.end())
		postProcEffects.erase(i);
}