#include "OpenGLView.h"

#include <QTimer>
#include <QMouseEvent>

#include "CommSerialDef.h"
#include "CommDef.h"

CTexture::CTexture()
{
    m_nTextureNum = 0;
    m_nCurrentTextureIndex = 0;
    m_bInit = false;
    m_bGenTextureData = false;

    for(int i = 0; i < MAX_TEXTURES; i++)
    {
        m_nTextures[i] = -1;
    }
}

CTexture::~CTexture()
{
    Unint();
}

void CTexture::Init(int nTextureNum)
{
    Unint();

    m_nTextureNum = (nTextureNum > MAX_TEXTURES) ? MAX_TEXTURES : nTextureNum;
    m_nTextureNum = (nTextureNum < 1) ? 1 : nTextureNum;

    glGenTextures(m_nTextureNum, &m_nTextures[0]);

    m_bInit = true;
}

void CTexture::Unint()
{
    if(m_bInit)
    {
        // 删除所有的纹理
        glDeleteTextures(m_nTextureNum, &m_nTextures[0]);

        for(int i = 0; i < MAX_TEXTURES; i++)
        {
            m_nTextures[i] = -1;
        }

        m_nTextureNum = 0;

        m_bInit = false;

        m_bGenTextureData = false;
    }
}

bool CTexture::GenTextureData(int nTextureIndex, int nTextureWidth, int nTextureHeight, int nDataWidth)
{
    if(!m_bInit)
    {
        return false;
    }

    if(nTextureIndex < 0 || nTextureIndex >= m_nTextureNum)
    {
        return false;
    }

    m_nCurrentTextureIndex = nTextureIndex;

    int nTextureComposite = 0;

    int nBytesOfPixel = nDataWidth / 8;

    switch (nBytesOfPixel)
    {
    case 1:
    {
        nTextureComposite = GL_LUMINANCE;
        break;
    }
    case 3:
    {
        nTextureComposite = GL_RGB;
        break;
    }
    case 4:
    {
        nTextureComposite = GL_RGBA;
        break;
    }
    default:
    {
        nTextureComposite = GL_RGBA;
        break;
    }
    }

    unsigned char* pTextureData = new unsigned char[nTextureWidth * nTextureHeight * nBytesOfPixel];

    memset(pTextureData, 128, nTextureWidth * nTextureHeight * nBytesOfPixel);

    glBindTexture(GL_TEXTURE_2D, m_nTextures[m_nCurrentTextureIndex]);

    glTexImage2D(GL_TEXTURE_2D, 0, nTextureComposite, nTextureWidth, nTextureHeight, 0, nTextureComposite, GL_UNSIGNED_BYTE, pTextureData);

    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );

    delete [] pTextureData;
    pTextureData = nullptr;

    m_bGenTextureData = true;

    return true;
}

//bmp图片默认RGBA
bool CTexture::UpdataTextureGray(int nTextureIndex, char* pTextureData, int nTextureWidth, int nTextureHeight)
{
    if(nTextureIndex < 0 || nTextureIndex >= m_nTextureNum)
    {
        return false;
    }

    m_nCurrentTextureIndex = nTextureIndex;

    glBindTexture(GL_TEXTURE_2D, m_nTextures[nTextureIndex]);

    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

    glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, nTextureWidth, nTextureHeight, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, pTextureData);

    return true;
}

bool CTexture::UpdataTexture(int nTextureIndex, char* pTextureData, int nTextureWidth, int nTextureHeight)
{
    if(nTextureIndex < 0 || nTextureIndex >= m_nTextureNum)
    {
        return false;
    }

    m_nCurrentTextureIndex = nTextureIndex;

    glBindTexture(GL_TEXTURE_2D, m_nTextures[nTextureIndex]);

    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, nTextureWidth, nTextureHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, pTextureData);

    return true;
}

GLuint  CTexture::CurrentTexture()
{
    if(!m_bInit)
    {
        return -1;
    }

    if(!m_bGenTextureData)
    {
        return -1;
    }

    return m_nTextures[m_nCurrentTextureIndex];
}

OpenGLView::OpenGLView(QWidget *parent, int iID, Qt::WindowFlags f)
{
    setWindowFlags(Qt::CustomizeWindowHint|Qt::FramelessWindowHint);
    this->setParent(parent);

    m_parentWidget = parent;
    OnMouseCallback = nullptr;

    m_nXPos = 0;
    m_nYPos = 0;
    m_dRatio = 1;

    m_pPBOBuffer[0] = nullptr;
    m_pPBOBuffer[1] = nullptr;

    m_nPBO_Now = 0;
    m_nPBO_Next = 0;

    m_pImageDataBuffer = nullptr;

    m_bInit = false;
    m_nImageWidth = 0;
    m_nImageHeight = 0;
    m_nImageDataSize = 0;

    m_bInitedGLRes = false;

    m_nRefreshCount = 0;

    m_eViewOrder = eViewOrder_Origin;
}

OpenGLView::~OpenGLView()
{
    UninitGLRes();

    Uninit();

    m_varTimer.stop();
    disconnect(&m_varTimer, &QTimer::timeout, this, &OpenGLView::OnTimer_Update);

    delete[] m_pImageDataBuffer;
    m_pImageDataBuffer = nullptr;

    m_bInit = false;

    for (int i = 0; i < 2; i++)
    {
        //1
        if (m_pPBOBuffer[i])
        {
            m_pPBOBuffer[i]->release();
        }
    }
}

bool    OpenGLView::Init(int nImageWidth, int nImageHeight)
{
    Uninit();

    //
    m_bInitedGLRes = false;

    //
    m_nImageWidth = nImageWidth;
    m_nImageHeight = nImageHeight;
    m_nImageDataSize = m_nImageWidth * m_nImageHeight * 4;

    m_varImageData.InitQueue(m_nImageDataSize, 2);

    //
    m_pImageDataBuffer = new byte[m_nImageWidth * m_nImageHeight * 4];
    memset(m_pImageDataBuffer, 108, m_nImageWidth * m_nImageHeight * 4);

    if(nullptr == m_pImageDataBuffer)
    {
        return false;
    }

    for (int h = 0; h < m_nImageHeight; h++)
    {
        memset(m_pImageDataBuffer + h*m_nImageWidth*4, h, m_nImageWidth*4);
    }

    //
    connect(&m_varTimer, &QTimer::timeout, this, &OpenGLView::OnTimer_Update);
    connect(&m_varTimer, &QTimer::timeout, this, &OpenGLView::OnTimer_InitGLRes);
    m_varTimer.setTimerType(Qt::PreciseTimer);
    m_varTimer.start(5);

    //
    m_bInit = true;

    //
    m_nRefreshCount = 2;

    return true;
}

void    OpenGLView::Uninit()
{
    if(m_bInit)
    {
        disconnect(&m_varTimer, &QTimer::timeout, this, &OpenGLView::OnTimer_Update);

        m_varTimer.stop();

        if(nullptr != m_pImageDataBuffer)
        {
            delete [] m_pImageDataBuffer;
            m_pImageDataBuffer = nullptr;
        }

        m_bInit = false;
    }
}

bool    OpenGLView::InitGLRes()
{
    UninitGLRes();

    if(!m_bInit)
    {
        return false;
    }

    //
    m_varTexture.Init(1);
    m_varTexture.GenTextureData(0, m_nImageWidth, m_nImageHeight, 32);  // RGBA纹理

    //
    for (int i = 0; i < 2; i++)
    {
        //1
        m_pPBOBuffer[i] = new QOpenGLBuffer(QOpenGLBuffer::PixelUnpackBuffer);
        m_pPBOBuffer[i]->create();
        m_pPBOBuffer[i]->allocate(m_nImageDataSize);
        m_pPBOBuffer[i]->bind();
    }

    initializeGLFunctions();
    glClearColor(0, 0, 255, 255);

    return true;
}

void    OpenGLView::UninitGLRes()
{
    //
    for (int i = 0; i < 2; i++)
    {
        if(nullptr != m_pPBOBuffer[i])
        {
            m_pPBOBuffer[i]->release();
            m_pPBOBuffer[i]->destroy();

            delete m_pPBOBuffer[i];
            m_pPBOBuffer[i] = nullptr;
        }
    }
}

void    OpenGLView::UpdateImageData(byte* pImageData, bool bTryFresh)
{
    if(!m_bInit || !m_bInitedGLRes)
    {
        return;
    }

    int nRes = 0;
    m_varImageData.PushBack(pImageData, m_nImageDataSize, nRes);

    if(bTryFresh)
    {
        m_nRefreshCount = 2;
    }
}

void OpenGLView::initializeGL()
{
    m_bInitedGLRes = true;
    InitGLRes();
}

//窗口大小响应函数，在创建窗口时系统会自动调用
void OpenGLView::resizeGL(int nViewWidth, int nViewHeight)
{
    if(!m_bInit)
    {
        return;
    }

    //按比例绘制
    int iX = 0, iY = 0;         //窗口中显示视图的左上角坐标
    GLdouble Ratio_W =  GLdouble(nViewWidth)/m_nImageWidth;
    GLdouble Ratio_H =  GLdouble(nViewHeight)/m_nImageHeight;
    GLdouble Ratio = Ratio_W<Ratio_H?Ratio_W:Ratio_H;

    if(Ratio_W<=Ratio_H)
    {
        iX = 0;
        iY = (nViewHeight-m_nImageHeight*Ratio)/2;
    }
    else if(Ratio_W>Ratio_H)
    {
        iX = (nViewWidth-m_nImageWidth*Ratio)/2;
        iY = 0;
    }
    glViewport(iX, iY, m_nImageWidth*Ratio, m_nImageHeight*Ratio+1);

    m_nXPos = iX;
    m_nYPos = iY;
    m_dRatio = Ratio;


    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    m_fScreenWid = GLfloat(nViewWidth) / nViewHeight;
    glFrustum(-m_fScreenWid, m_fScreenWid, -1.0, 1.0, 8.0, 100.0);
    glMatrixMode(GL_MODELVIEW);

}

void OpenGLView::paintGL()
{
    draw();
}

void OpenGLView::draw()
{
    if(!m_bInit)
    {
        return;
    }

    if(!m_bInitedGLRes)
    {
        return;
    }

    glClearColor(0.0f,0.0f,0.0f,1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

    glPushMatrix();

    glTranslatef(0.0, 0.0 + 1.0, -8.0);//0.5 + moveY
    glEnable(GL_TEXTURE_2D);

    glBindTexture(GL_TEXTURE_2D, m_varTexture.CurrentTexture());

    const bool c_bPboMode = true;

    if(c_bPboMode)
    {
        m_nPBO_Now = (m_nPBO_Now + 1) % 2;
        m_nPBO_Next = (m_nPBO_Now + 1) % 2;

        m_pPBOBuffer[m_nPBO_Now]->bind();

        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, m_nImageWidth, m_nImageHeight, GL_RGBA, GL_UNSIGNED_BYTE, 0);

        //..CPU导入数据采用的是DMA模式；从CPU将最新图像数据导入GPU贴图缓冲区
        m_pPBOBuffer[m_nPBO_Next]->bind();
        glBufferData(GL_PIXEL_UNPACK_BUFFER, m_nImageDataSize, 0, GL_STREAM_DRAW);

        void* pGpuMem = m_pPBOBuffer[m_nPBO_Next]->map(QOpenGLBuffer::WriteOnly);

        if(nullptr != pGpuMem)
        {
            memcpy(pGpuMem, m_pImageDataBuffer, m_nImageDataSize);
        }

        m_pPBOBuffer[m_nPBO_Next]->unmap();
    }
    else//CPU导入数据，使用CPU拷贝模式；占用CPU的运算资源
    {
//        textr->UpdataTexture(iTexA[0], (char *)m_byTemp, DefaultImageWidth, DefaultImageHeight * m_iImageNum);//iTexA[0]//m_iTextureID
    }

    glColor3f(1.0,1.0,1.0);                 // 设置颜色
    glShadeModel(GL_SMOOTH);                // 设置平滑
    glDepthMask(GL_FALSE);                  // 关闭深度
    glBegin(GL_TRIANGLE_STRIP);             // 三角片序列绘制

    switch (m_eViewOrder)
    {
    case eViewOrder_Origin:
    {
        glTexCoord2f(0.0f, 0.0f);               // 第一个点纹理坐标设置
        glVertex3f(-m_fScreenWid, 0.0f, 0.0f);  // 第一个点三维坐标设置
        glTexCoord2f(0.0f, 1.0f);               // 第二个点纹理坐标设置
        glVertex3f(-m_fScreenWid, -2.0f, 0.0f); // 第二个点三维坐标设置
        glTexCoord2f(1.0f, 0.0f);               // 第三个点纹理坐标设置
        glVertex3f(m_fScreenWid, 0.0f, 0.0f);   // 第三个点三维坐标设置
        glTexCoord2f(1.0f, 1.0f);               // 第四个点纹理坐标设置
        glVertex3f(m_fScreenWid, -2.0f, 0.0f);  // 第四个点三维坐标设置

        break;
    }
    case eViewOrder_LeftRightRevert:
    {
        glTexCoord2f(0.0f, 0.0f);
        glVertex3f(m_fScreenWid, 0.0f, 0.0f);
        glTexCoord2f(0.0f, 1.0f);
        glVertex3f(m_fScreenWid, -2.0f, 0.0f);
        glTexCoord2f(1.0f, 0.0f);
        glVertex3f(-m_fScreenWid, 0.0f, 0.0f);
        glTexCoord2f(1.0f, 1.0f);
        glVertex3f(-m_fScreenWid, -2.0f, 0.0f);

        break;
    }
    case eViewOrder_UpDownRevert:
    {
        glTexCoord2f(0.0f, 0.0f);
        glVertex3f(-m_fScreenWid, -2.0f, 0.0f);
        glTexCoord2f(0.0f, 1.0f);
        glVertex3f(-m_fScreenWid, 0.0f, 0.0f);
        glTexCoord2f(1.0f, 0.0f);
        glVertex3f(m_fScreenWid, -2.0f, 0.0f);
        glTexCoord2f(1.0f, 1.0f);
        glVertex3f(m_fScreenWid, 0.0f, 0.0f);

        break;
    }
    case eViewOrder_AllRevert:
    {
        glTexCoord2f(0.0f, 0.0f);
        glVertex3f(m_fScreenWid, -2.0f, 0.0f);
        glTexCoord2f(0.0f, 1.0f);
        glVertex3f(m_fScreenWid, 0.0f, 0.0f);
        glTexCoord2f(1.0f, 0.0f);
        glVertex3f(-m_fScreenWid, -2.0f, 0.0f);
        glTexCoord2f(1.0f, 1.0f);
        glVertex3f(-m_fScreenWid, 0.0f, 0.0f);

        break;
    }
    default: // origin
    {
        glTexCoord2f(0.0f, 0.0f);               // 第一个点纹理坐标设置
        glVertex3f(-m_fScreenWid, 0.0f, 0.0f);  // 第一个点三维坐标设置
        glTexCoord2f(0.0f, 1.0f);               // 第二个点纹理坐标设置
        glVertex3f(-m_fScreenWid, -2.0f, 0.0f); // 第二个点三维坐标设置
        glTexCoord2f(1.0f, 0.0f);               // 第三个点纹理坐标设置
        glVertex3f(m_fScreenWid, 0.0f, 0.0f);   // 第三个点三维坐标设置
        glTexCoord2f(1.0f, 1.0f);               // 第四个点纹理坐标设置
        glVertex3f(m_fScreenWid, -2.0f, 0.0f);  // 第四个点三维坐标设置

        break;
    }
    }

    glEnd();                    // 三角片序列绘制结束
    glDisable(GL_TEXTURE_2D);   // 不使能纹理
    glDepthMask(GL_TRUE);       // 使能深度

    glPopMatrix();              // 弹栈
}

void OpenGLView::OnTimer_Update()
{
    if(!m_bInit)
    {
        return;
    }

    if(!m_bInitedGLRes)
    {
        return;
    }

    //
    if(m_nRefreshCount > 0)
    {
        m_nRefreshCount--;

        this->updateGL();
    }

    //
    int nFrameSize = 0;

    if(!m_varImageData.GetFront(m_pImageDataBuffer, nFrameSize) )
    {
        return;
    }

    this->updateGL();
}

void    OpenGLView::OnTimer_InitGLRes()
{
    if(!m_bInitedGLRes)
    {
        InitGLRes();

        m_bInitedGLRes = true;
    }
}

bool    OpenGLView::event(QEvent* event)
{
    if (m_parentWidget && OnMouseCallback)
    {
        if(event->type() == QEvent::Leave || event->type() == QEvent::Enter ||
        event->type() == QEvent::MouseButtonPress || event->type() == QEvent::MouseMove ||
        event->type() == QEvent::MouseButtonRelease || event->type() == QEvent::MouseButtonDblClick ||
        event->type() == QEvent::Enter || event->type() == QEvent::Leave
                )
        {
            //OnMouseCallback(m_iID, event, m_parentWidget);
        }
    }

    return QWidget::event(event);
}

void    OpenGLView::SetCallbackFunc(MouseEventCallback callback)
{
    OnMouseCallback = callback;
}

void    OpenGLView::SetViewOrder(eViewOrder viewOrder)
{
    m_eViewOrder = viewOrder;
}