/* Copyright (C) 2019
 * swift project Community / Contributors
 *
 * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
 * directory of this distribution. No part of swift project, including this file, may be copied, modified, propagated,
 * or distributed except according to the terms contained in the LICENSE file.
 */

//! \file

#include "callsignsampleprovider.h"
#include "callsigndelaycache.h"
#include "blacksound/sampleprovider/samples.h"
#include <QtMath>
#include <QDebug>

namespace BlackCore
{
    namespace Afv
    {
        namespace Audio
        {
            CallsignSampleProvider::CallsignSampleProvider(const QAudioFormat &audioFormat, QObject *parent) :
                ISampleProvider(parent),
                m_audioFormat(audioFormat),
                m_decoder(audioFormat.sampleRate(), 1)
            {
                Q_ASSERT(audioFormat.channelCount() == 1);

                mixer = new MixingSampleProvider(this);
                crackleSoundProvider = new ResourceSoundSampleProvider(Samples::instance().crackle(), mixer);
                crackleSoundProvider->setLooping(true);
                crackleSoundProvider->setGain(0.0);
                whiteNoise = new ResourceSoundSampleProvider(Samples::instance().whiteNoise(), mixer);
                whiteNoise->setLooping(true);
                whiteNoise->setGain(0.0);
                acBusNoise = new SawToothGenerator(400, mixer);
                audioInput = new BufferedWaveProvider(audioFormat, mixer);

                // Create the compressor
                simpleCompressorEffect = new SimpleCompressorEffect(audioInput, mixer);
                simpleCompressorEffect->setMakeUpGain(-5.5);

                // Create the voice EQ
                voiceEq = new EqualizerSampleProvider(simpleCompressorEffect, EqualizerPresets::VHFEmulation, mixer);

                mixer->addMixerInput(whiteNoise);
                mixer->addMixerInput(acBusNoise);
                mixer->addMixerInput(voiceEq);

                m_timer.setInterval(100);
                connect(&m_timer, &QTimer::timeout, this, &CallsignSampleProvider::timerElapsed);
            }

            int CallsignSampleProvider::readSamples(QVector<qint16> &samples, qint64 count)
            {
                int noOfSamples = mixer->readSamples(samples, count);

                if (m_inUse && m_lastPacketLatch && audioInput->getBufferedBytes() == 0)
                {
                    idle();
                    m_lastPacketLatch = false;
                }

                if (m_inUse && !m_underflow && audioInput->getBufferedBytes() == 0)
                {
                    qDebug() << "[" << m_callsign <<  "] [Delay++]";
                    CallsignDelayCache::instance().underflow(m_callsign);
                    m_underflow = true;
                }

                return noOfSamples;
            }

            void CallsignSampleProvider::timerElapsed()
            {
                if (m_inUse && audioInput->getBufferedBytes() == 0 && m_lastSamplesAddedUtc.msecsTo(QDateTime::currentDateTimeUtc()) > idleTimeoutMs)
                {
                    idle();
                }
            }

            QString CallsignSampleProvider::type() const
            {
                return m_type;
            }

            void CallsignSampleProvider::active(const QString &callsign, const QString &aircraftType)
            {
                m_callsign = callsign;
                CallsignDelayCache::instance().initialise(callsign);
                m_type = aircraftType;
                m_decoder.resetState();
                m_inUse = true;
                setEffects();
                m_underflow = false;

                int delayMs = CallsignDelayCache::instance().get(callsign);
                qDebug() << "[" << m_callsign << "] [Delay " << delayMs << "ms]";
                if (delayMs > 0)
                {
                    int phaseDelayLength = (m_audioFormat.sampleRate() / 1000) * delayMs;
                    QVector<qint16> phaseDelay(phaseDelayLength * 2, 0);
                    audioInput->addSamples(phaseDelay);
                }
            }

            void CallsignSampleProvider::activeSilent(const QString &callsign, const QString &aircraftType)
            {
                m_callsign = callsign;
                CallsignDelayCache::instance().initialise(callsign);
                m_type = aircraftType;
                m_decoder.resetState();
                m_inUse = true;
                setEffects(true);
                m_underflow = true;
            }

            void CallsignSampleProvider::clear()
            {
                idle();
                audioInput->clearBuffer();
            }

            void CallsignSampleProvider::addOpusSamples(const IAudioDto &audioDto, float distanceRatio)
            {
                m_distanceRatio = distanceRatio;

                QVector<qint16> audio = decodeOpus(audioDto.audio);
                audioInput->addSamples(audio);
                m_lastPacketLatch = audioDto.lastPacket;
                if (audioDto.lastPacket && !m_underflow)
                    CallsignDelayCache::instance().success(m_callsign);

                m_lastSamplesAddedUtc = QDateTime::currentDateTimeUtc();
                if (!m_timer.isActive()) { m_timer.start(); }
            }

            void CallsignSampleProvider::addSilentSamples(const IAudioDto &audioDto)
            {
                // Disable all audio effects
                setEffects(true);

                // TODO audioInput->addSamples(decoderByteBuffer, 0, frameCount * 2);
                m_lastPacketLatch = audioDto.lastPacket;

                m_lastSamplesAddedUtc = QDateTime::currentDateTimeUtc();
                if (!m_timer.isActive()) { m_timer.start(); }
            }

            void CallsignSampleProvider::idle()
            {
                m_timer.stop();
                m_inUse = false;
                setEffects();
                m_callsign = QString();
                m_type = QString();
            }

            QVector<qint16> CallsignSampleProvider::decodeOpus(const QByteArray &opusData)
            {
                int decodedLength = 0;
                QVector<qint16> decoded = m_decoder.decode(opusData, opusData.size(), &decodedLength);
                return decoded;
            }

            void CallsignSampleProvider::setEffects(bool noEffects)
            {
                if (noEffects || m_bypassEffects || !m_inUse)
                {
                    crackleSoundProvider->setGain(0.0);
                    whiteNoise->setGain(0.0);
                    acBusNoise->setGain(0.0);
                    simpleCompressorEffect->setEnabled(false);
                    voiceEq->setBypassEffects(true);
                }
                else
                {
                    float crackleFactor = (float)(((qExp(m_distanceRatio) * qPow(m_distanceRatio, -4.0)) / 350) - 0.00776652);

                    if (crackleFactor < 0.0f) { crackleFactor = 0.0f; }
                    if (crackleFactor > 0.20f) { crackleFactor = 0.20f; }

                    crackleSoundProvider->setGain(crackleFactor * 2);
                    whiteNoise->setGain(whiteNoiseGainMin);
                    acBusNoise->setGain(acBusGainMin);
                    simpleCompressorEffect->setEnabled(true);
                    voiceEq->setBypassEffects(false);
                    voiceEq->setOutputGain(1.0 - crackleFactor * 3.7);
                }
            }

            void CallsignSampleProvider::setBypassEffects(bool bypassEffects)
            {
                m_bypassEffects = bypassEffects;
                setEffects();
            }

            bool CallsignSampleProvider::inUse() const
            {
                return m_inUse;
            }
        } // ns
    } // ns
} // ns