#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QMessageBox>
#include <QFileDialog>
#include <QTextCodec>
#include <QDebug>

#define DELETE_OBJ(object)  if(nullptr != object)\
                            {\
                                delete object;\
                                object = nullptr;\
                            }

inline QString GBK2UTF8(const char *inStr)
{
    QTextCodec *gbk = QTextCodec::codecForName("GBK");
    QString g2u;
    if(nullptr != gbk)
    {
        g2u = gbk->toUnicode(inStr);
    }
    else
    {
        g2u = inStr;
    }
    return g2u;
}

inline QString UTF82GBK(const char *inStr)
{
    QTextCodec *utf8 = QTextCodec::codecForName("UTF-8");
    QString utf2gbk;
    if(nullptr != utf8)
    {
        utf2gbk = utf8->toUnicode(inStr);
    }
    else
    {
        utf2gbk = inStr;
    }
    return utf2gbk;
}


MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow),
    m_audioOutput(nullptr),
    m_streamOut(nullptr),
    m_perFrameSize(0),
    workThread(nullptr),
    worked(false)
{
    ui->setupUi(this);
    ui->comboBox->addItem(GBK2UTF8("unsigned int"));
    ui->comboBox->addItem(GBK2UTF8("signed int"));
    ui->comboBox->addItem(GBK2UTF8("float"));
    ui->comboBox_2->addItem(GBK2UTF8("8"));
    ui->comboBox_2->addItem(GBK2UTF8("16"));
}


int MainWindow::playFrame(const char *data, unsigned int len)
{
    if(nullptr != m_audioOutput &&
            m_audioOutput->state() != QAudio::StoppedState &&
            m_audioOutput->state() != QAudio::SuspendedState)
    {
        unsigned int writeLen = 0;
        while ((len - writeLen) > 0)
        {
            /* 音频设备剩余的空间是否可以写"一段"音频 */
            if (m_audioOutput->bytesFree() < m_audioOutput->periodSize())
            {
                QThread::msleep(1);
                if ( m_audioOutput->state() == QAudio::StoppedState ||
                                m_audioOutput->state() == QAudio::SuspendedState){
                    return 0;
                }
                continue;
            }

            if ((len - writeLen)  >= m_audioOutput->periodSize())
            {
                //写入到扬声器
                m_streamOut->write(data + writeLen, m_audioOutput->periodSize());
            }
            else
            {
                //将最后剩下的数据写入到扬声器
                m_streamOut->write(data + writeLen, len - writeLen);
                break;
            }
            writeLen += m_audioOutput->periodSize();
        }
        return 0;
    }
    return -1;
}

const char *MainWindow::getFileName()
{
    return m_fileName.c_str();
}

unsigned int MainWindow::getFrameSize()
{
    return m_perFrameSize;
}

unsigned int MainWindow::getPorgressParTotal()
{
    return ui->progressBar->maximum();

}

void MainWindow::setPorgressParValue(unsigned int value)
{
    if(value <= ui->progressBar->maximum())
    {
        ui->progressBar->setValue(value);
    }
}

void MainWindow::setPorgressParMaxValue(unsigned int maxValue)
{
    ui->progressBar->setMaximum( maxValue);
}

void MainWindow::stopPlay()
{
    if(true == worked)
    {
        ui->progressBar->setValue(0);
        m_audioOutput->stop();
        m_audioOutput->reset();
        worked = false;
        ui->play->setText(GBK2UTF8("开始播放"));
        DELETE_OBJ(m_audioOutput);
    }
}

MainWindow::~MainWindow()
{
    on_pushButton_2_clicked();
    DELETE_OBJ(m_audioOutput);
    DELETE_OBJ(workThread);

    delete ui;
}

void MainWindow::on_actionOpen_triggered()
{
    m_fileName = QFileDialog::getOpenFileName(this, GBK2UTF8("打开文件") ,tr(""), GBK2UTF8("音频裸流文件(*.pcm);;所有文件(*.*)")).toStdString();
    if(false == m_fileName.empty())
    {
        //QMessageBox::information(this, GBK2UTF8("文件名称"), m_fileName.c_str());
        ui->labelFileName->setText(m_fileName.c_str());
    }
}

void MainWindow::on_play_clicked()
{
    if(m_fileName.empty())
    {
        return;
    }

    if(worked == true && m_audioOutput->state() == QAudio::ActiveState)
    {
        ui->play->setText(GBK2UTF8("继续"));
        m_audioOutput->suspend();
        return;
    }

    if(worked == true && m_audioOutput->state() == QAudio::SuspendedState)
    {
        ui->play->setText(GBK2UTF8("暂停"));
        m_audioOutput->resume();
        return;
    }

     //设置采样格式
     QAudioFormat audioFormat;

     if(ui->lineEdit->text().toInt() <= 0)
     {
         return;
     }
     //设置采样率
     audioFormat.setSampleRate(ui->lineEdit->text().toInt());

     if(ui->lineEdit_2->text().toInt() <= 0)
     {
         return;
     }

     //设置通道数
     audioFormat.setChannelCount(ui->lineEdit_2->text().toInt());

     if(ui->lineEdit_2->text().toInt() <= 0)
     {
         return;
     }
    if(QString::compare("unsigned int", ui->comboBox->currentText()) == 0)
    {
        //设置样本数据类型
        audioFormat.setSampleType(QAudioFormat::UnSignedInt);
    }
    else if(QString::compare("signed int", ui->comboBox->currentText()) == 0)
    {
        //设置样本数据类型
        audioFormat.setSampleType(QAudioFormat::SignedInt);
    }
    else
    {
        //设置样本数据类型
        audioFormat.setSampleType(QAudioFormat::Float);
    }

    //设置采样大小，一般为8位或16位
    audioFormat.setSampleSize(ui->comboBox_2->currentText().toInt());

     //设置编码方式
     audioFormat.setCodec("audio/pcm");
     //设置字节序
     audioFormat.setByteOrder(QAudioFormat::LittleEndian);

     m_perFrameSize = audioFormat.sampleRate() * audioFormat.channelCount() * ui->comboBox_2->currentText().toInt() / 8 ;

     //音频设备信息
     QAudioDeviceInfo info = QAudioDeviceInfo::defaultOutputDevice();
     if (!info.isFormatSupported(audioFormat))
     {
         qDebug()<<"default format not supported try to use nearest";
         audioFormat = info.nearestFormat(audioFormat);
     }

     m_audioOutput = new QAudioOutput(audioFormat, 0);
     m_streamOut = m_audioOutput->start();

    workThread = new  AudioPlayThread(this);
    if(nullptr != workThread)
    {
        workThread->start();
        worked = true;
        connect(workThread, &AudioPlayThread::updatePregressValue, this, &MainWindow::setPorgressParValue);
        connect(this, &MainWindow::stop, workThread, &AudioPlayThread::stopPlay);
        connect(workThread, &AudioPlayThread::playEnd, this, &MainWindow::stopPlay);
    }

    qDebug() << "periodSize:" << m_audioOutput->periodSize() << "bytesFree:" << m_audioOutput->bytesFree();
    ui->play->setText(GBK2UTF8("暂停"));
}

void MainWindow::on_pushButton_2_clicked()
{
    if(true == worked)
    {
        DELETE_OBJ(workThread);
        stopPlay();
    }
}

AudioPlayThread::AudioPlayThread(MainWindow *parent):m_parent(parent),QThread(parent),m_isExit(true)
{

}

void AudioPlayThread::stopPlay()
{
    m_isExit = true;
}

AudioPlayThread::~AudioPlayThread()
{
    m_isExit = true;
    if ( this->isRunning()){
        this->requestInterruption();
        this->quit();
        this->wait();
    }
}

void AudioPlayThread::run()
{
    if(nullptr == m_parent || m_isExit == false)
    {
        return;
    }
    m_isExit = false;

    int ret = 0;
    //获取文件的指针
    const char *fileName = m_parent->getFileName();
    if(nullptr == fileName)
    {
        qDebug()<< "file name is empty";
        return;
    }
    FILE *file = fopen(fileName,"rb");
    if(!file)
    {
        qDebug()<< "Open Failed";
        return;
    }
    //把指针移动到文件的结尾 ，获取文件长度
    fseek(file, 0, SEEK_END);
    //获取文件长度
    unsigned int fileLength = ftell(file);
    unsigned int frameSize = m_parent->getFrameSize();
    m_parent->setPorgressParMaxValue(fileLength);
    //定义数组长度
    char *fileBuffer = new char[frameSize];
    memset(fileBuffer, 0 , frameSize);
    //把指针移动到文件开头 因为我们一开始把指针移动到结尾，如果不移动回来 会出错
    rewind(file);
    int progressParPerAddNum =  frameSize;
    unsigned int progressCurrentValue = 0;

    qDebug()<< "frameSize:" << frameSize << " fileLength:" << fileLength << " progressParPerAddNum:" << progressParPerAddNum ;
    //读文件
    ret = fread(fileBuffer, 1, frameSize, file);
    while (ret > 0 && m_isExit == false)
    {
        while( m_parent->playFrame(fileBuffer, ret) != 0 && m_isExit == false)
        {
            QThread::msleep(1);
        }
        progressCurrentValue += progressParPerAddNum;
        emit updatePregressValue(progressCurrentValue);

        /* seek 1 frame(1 seconds) */
        //fseek(file, frameSize, SEEK_CUR);
        //读文件
        ret = fread(fileBuffer, 1, frameSize, file);
    }
    emit updatePregressValue(m_parent->getPorgressParTotal());

    //关闭文件
    fclose(file);
    //QMessageBox::information(m_parent, GBK2UTF8("提示"), "播放完成");
    delete fileBuffer;
    qDebug()<<fileLength << " ret:" << ret << GBK2UTF8("播放完成");
    emit playEnd();
}

void MainWindow::resizeEvent(QResizeEvent *e)
{
    ui->progressBar->resize( this->width() - ui->progressBar->x() *2, ui->progressBar->height());
    ui->labelFileName->resize( this->width() - ui->labelFileName->x() *2, ui->labelFileName->height());
}