#include "AudioPlayer.h"
#include <cstring>
#include <cmath>
#include <QDebug>

extern "C" {
#include <libavutil/avutil.h>
#include <libavutil/samplefmt.h>
#include <libavutil/channel_layout.h>
#include <libavutil/frame.h>
#include <libavutil/mem.h>
#include <libswresample/swresample.h>
}
#include "sonic/sonic.h"

AudioPlayer::AudioPlayer() {}
AudioPlayer::~AudioPlayer() { reset(); }

bool AudioPlayer::open(const AVFrame* frame, float speed) {
    qDebug() << "[AUDIO-PLAYER] open: sample_rate=" << frame->sample_rate << "channels=" << frame->ch_layout.nb_channels << "format=" << frame->format << "speed=" << speed;
    QMutexLocker locker(&m_mutex);
    qDebug() << "[AUDIO-PLAYER] got mutex";
    reset();
    qDebug() << "[AUDIO-PLAYER] after reset";
    return initAudioOutput(frame, speed);
}

bool AudioPlayer::initAudioOutput(const AVFrame* frame, float speed) {
    qDebug() << "[AUDIO-PLAYER] initAudioOutput begin";
    m_sampleRate = frame->sample_rate;
    m_channels = frame->ch_layout.nb_channels;
    m_format = (AVSampleFormat)frame->format;
    m_speed = speed;
    m_volume = 1.0f;
    releaseSonic();
    ensureSonic(m_sampleRate, m_channels);
    setSpeed(speed);
    QAudioFormat fmt;
    fmt.setSampleRate(m_sampleRate);
    fmt.setChannelCount(m_channels);
    fmt.setSampleSize(16); // S16
    fmt.setCodec("audio/pcm");
    fmt.setByteOrder(QAudioFormat::LittleEndian);
    fmt.setSampleType(QAudioFormat::SignedInt);
    qDebug() << "[AUDIO-PLAYER] before QAudioOutput, deviceInfo isNull=" << m_deviceInfo.isNull();
    if (!m_deviceInfo.isNull()) {
        if (!m_deviceInfo.isFormatSupported(fmt)) {
            qWarning() << "音频格式不支持，尝试最近格式";
            fmt = m_deviceInfo.nearestFormat(fmt);
        }
        qDebug() << "[AUDIO-PLAYER] before QAudioOutput (custom device)";
        m_audioOutput = new QAudioOutput(m_deviceInfo, fmt, nullptr);
    } else {
        QAudioDeviceInfo info(QAudioDeviceInfo::defaultOutputDevice());
        if (!info.isFormatSupported(fmt)) {
            qWarning() << "音频格式不支持，尝试最近格式";
            fmt = info.nearestFormat(fmt);
        }
        qDebug() << "[AUDIO-PLAYER] before QAudioOutput (default device)";
        m_audioOutput = new QAudioOutput(fmt, nullptr);
    }
    qDebug() << "[AUDIO-PLAYER] after QAudioOutput, m_audioOutput=" << m_audioOutput;
    // m_audioOutput->setBufferSize(16384);
    m_audioOutput->setVolume(m_volume);
    qDebug() << "[AUDIO-PLAYER] before start";
    m_audioDevice = m_audioOutput->start();
    qDebug() << "[AUDIO-PLAYER] after start, m_audioDevice=" << m_audioDevice;
    return m_audioDevice != nullptr;
}

bool AudioPlayer::play(const AVFrame* frame, float speed) {
    QMutexLocker locker(&m_mutex);
    if (!m_audioDevice) return false;
    if (m_sampleRate != frame->sample_rate || m_channels != frame->ch_layout.nb_channels || m_format != (AVSampleFormat)frame->format) {
        open(frame, speed);
    }
    m_speed = speed;
    setSpeed(speed);
    // 1. 重采样到 S16
    const AVSampleFormat targetFmt = AV_SAMPLE_FMT_S16;
    uint8_t* inputData = nullptr;
    int inputSamples = frame->nb_samples;
    int inputBytes = av_samples_get_buffer_size(nullptr, m_channels, inputSamples, targetFmt, 1);
    if (m_format != targetFmt) {
        ensureResampler(frame);
        if (!m_swrBuffer || m_swrBufferSize < inputBytes) {
            if (m_swrBuffer) av_free(m_swrBuffer);
            m_swrBuffer = (uint8_t*)av_malloc(inputBytes);
            m_swrBufferSize = inputBytes;
        }
        int outSamples = swr_convert(
            m_swrCtx,
            &m_swrBuffer, inputSamples,
            (const uint8_t**)frame->extended_data, inputSamples
        );
        inputData = m_swrBuffer;
        inputSamples = outSamples;
        inputBytes = av_samples_get_buffer_size(nullptr, m_channels, outSamples, targetFmt, 1);
    } else {
        inputData = frame->data[0];
        inputBytes = av_samples_get_buffer_size(nullptr, m_channels, inputSamples, targetFmt, 1);
    }
    // 2. 送 sonic 变速
    ensureSonic(m_sampleRate, m_channels);
    setSpeed(speed);
    int out_ret = sonicWriteShortToStream(m_sonicCtx, (int16_t*)inputData, inputBytes / (m_channels * 2));
    int num_samples = sonicSamplesAvailable(m_sonicCtx);
    int out_size = num_samples * 2 * m_channels;
    av_fast_malloc(&m_abufOut, &m_abufOutSize, out_size);
    int sonic_samples = 0;
    if (out_ret) {
        sonic_samples = sonicReadShortFromStream(m_sonicCtx, (int16_t*)m_abufOut, num_samples);
        out_size = sonic_samples * 2 * m_channels;
    }
    // 3. 写入音频设备前判断可用空间
    if (m_audioOutput && m_audioOutput->bytesFree() < out_size) {
        qWarning() << "[AUDIO] QAudioOutput 缓冲区不够，丢帧 out_size=" << out_size << "bytesFree=" << m_audioOutput->bytesFree();
        return false;
    }
    if (out_size > 0)
        m_audioDevice->write((const char*)m_abufOut, out_size);
    return true;
}

void AudioPlayer::setSpeed(float speed) {
    // QMutexLocker locker(&m_mutex);
    m_speed = speed;
    if (m_sonicCtx) {
        sonicSetSpeed(m_sonicCtx, speed);
        sonicSetPitch(m_sonicCtx, 1.0f);
        sonicSetRate(m_sonicCtx, 1.0f);
    }
}

void AudioPlayer::setVolume(float volume) {
    QMutexLocker locker(&m_mutex);
    m_volume = volume;
    if (m_audioOutput) {
        m_audioOutput->setVolume(volume);
    }
}

bool AudioPlayer::setOutputDevice(const QAudioDeviceInfo& deviceInfo) {
    QMutexLocker locker(&m_mutex);
    m_deviceInfo = deviceInfo;
    if (m_audioOutput) {
        m_audioOutput->stop();
        delete m_audioOutput;
        m_audioOutput = nullptr;
    }
    return true;
}

void AudioPlayer::stop() {
    QMutexLocker locker(&m_mutex);
    if (m_audioOutput) {
        m_audioOutput->stop();
    }
}

void AudioPlayer::reset()
{
    releaseSonic();
    releaseResampler();
    releaseAudioOutput();
    if (m_abufOut) {
        av_freep(&m_abufOut);
        m_abufOut = nullptr;
        m_abufOutSize = 0;
    }
    m_sampleRate = 0;
    m_channels = 0;
    m_format = AV_SAMPLE_FMT_NONE;
    m_speed = 1.0f;
    m_volume = 1.0f;
    m_deviceInfo = QAudioDeviceInfo();
}

void AudioPlayer::freeBuffers() {
    if (m_abufOut) {
        av_freep(&m_abufOut);
        m_abufOut = nullptr;
        m_abufOutSize = 0;
    }
}

bool AudioPlayer::ensureResampler(const AVFrame* frame) {
    if (!m_swrCtx) {
        m_swrCtx = swr_alloc();
        swr_alloc_set_opts2(&m_swrCtx,
                            &frame->ch_layout, // out_ch_layout
                            AV_SAMPLE_FMT_S16,
                            frame->sample_rate,
                            &frame->ch_layout, // in_ch_layout
                            (AVSampleFormat)frame->format,
                            frame->sample_rate,
                            0,
                            nullptr);
        swr_init(m_swrCtx);
    }
    return m_swrCtx != nullptr;
}

void AudioPlayer::releaseResampler() {
    if (m_swrCtx) {
        swr_free(&m_swrCtx);
        m_swrCtx = nullptr;
    }
    if (m_swrBuffer) {
        av_free(m_swrBuffer);
        m_swrBuffer = nullptr;
        m_swrBufferSize = 0;
    }
}

bool AudioPlayer::ensureSonic(int sampleRate, int channels) {
    if (!m_sonicCtx) {
        m_sonicCtx = sonicCreateStream(sampleRate, channels);
    }
    return m_sonicCtx != nullptr;
}

void AudioPlayer::releaseSonic() {
    if (m_sonicCtx) {
        sonicDestroyStream(m_sonicCtx);
        m_sonicCtx = nullptr;
    }
}

void AudioPlayer::releaseAudioOutput() {
    if (m_audioOutput) {
        m_audioOutput->stop();
        delete m_audioOutput;
        m_audioOutput = nullptr;
    }
    m_audioDevice = nullptr;
}

QIODevice* AudioPlayer::getOutputDevice() const {
    return m_audioDevice;
}

QAudioOutput* AudioPlayer::getAudioOutput() const {
    return m_audioOutput;
}

float AudioPlayer::getSpeed() const {
    return m_speed;
}

float AudioPlayer::getVolume() const {
    return m_volume;
}