#include "XVideoWidget.h"
#include "ui_XVideoWidget.h"

//自动加双引号
#define GET_STR(x) #x
#define A_VER 3
#define T_VER 4

//顶点shader
const char *vString = GET_STR(
    attribute vec4 vertexIn;
    attribute vec2 textureIn;
    varying vec2 textureOut;
    void main(void)
    {
        gl_Position = vertexIn;
        textureOut = textureIn;
    }
);


//片元shader
const char *tString = GET_STR(
    varying vec2 textureOut;
    uniform sampler2D tex_y;
    uniform sampler2D tex_u;
    uniform sampler2D tex_v;
    void main(void)
    {
        vec3 yuv;
        vec3 rgb;
        yuv.x = texture2D(tex_y, textureOut).r;
        yuv.y = texture2D(tex_u, textureOut).r - 0.5;
        yuv.z = texture2D(tex_v, textureOut).r - 0.5;
        rgb = mat3(1.0, 1.0, 1.0,
            0.0, -0.39465, 2.03211,
            1.13983, -0.58060, 0.0) * yuv;
        gl_FragColor = vec4(rgb, 1.0);
    }
);

XVideoWidget::XVideoWidget(QWidget *parent) :
    QOpenGLWidget(parent)
  , ui(new Ui::XVideoWidget)
{
    ui->setupUi(this);
}

XVideoWidget::~XVideoWidget()
{
    delete ui;
}

void XVideoWidget::Init(int _iWidget, int _iHeight)
{
    m_qmutVideoWidget.lock();

    m_iWidth = _iWidget;
    m_iHeight = _iHeight;

    qDebug()<<"XVideoWidget m_iWidth == "<<m_iWidth;
    qDebug()<<"XVideoWidget m_iHeight == "<<m_iHeight;

    delete m_pDatas[0];
    delete m_pDatas[1];
    delete m_pDatas[2];

    //分配材质内存空间
    m_pDatas[0] = new unsigned char[m_iWidth * m_iHeight];
    m_pDatas[1] = new unsigned char[m_iWidth * m_iHeight / 4];
    m_pDatas[2] = new unsigned char[m_iWidth * m_iHeight / 4];

    if(texs[0])
    {
        glDeleteTextures(3, texs);
    }

    //创建材质
    glGenTextures(3, texs);
    for(GLenum err; (err = glGetError()) != GL_NO_ERROR;)
    {
        qDebug()<<"err:"<<err;
    }

    //Y绑定材质
    glBindTexture(GL_TEXTURE_2D, texs[0]);

    //放大过滤，线性插值 GL_NEAREST(效率高， 但马赛克严重)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    //创建材质显卡空间
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, m_iWidth, m_iHeight, 0, GL_RED, GL_UNSIGNED_BYTE, 0);

    //U绑定材质
    glBindTexture(GL_TEXTURE_2D, texs[1]);

    //放大过滤，线性插值 GL_NEAREST(效率高， 但马赛克严重)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    //创建材质显卡空间
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, m_iWidth / 2, m_iHeight / 2, 0, GL_RED, GL_UNSIGNED_BYTE, 0);

    //V绑定材质
    glBindTexture(GL_TEXTURE_2D, texs[2]);

    //放大过滤，线性插值 GL_NEAREST(效率高， 但马赛克严重)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    //创建材质显卡空间
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, m_iWidth / 2, m_iHeight / 2, 0, GL_RED, GL_UNSIGNED_BYTE, 0);

    m_qmutVideoWidget.unlock();
}

void XVideoWidget::Repaint(AVFrame *_pAVFrame)
{
    //qDebug()<<"XVideoWidget::Repaint";
    if(_pAVFrame == nullptr)
    {
        qDebug()<<"_pAVFrame == nullptr";
        return;
    }

    m_qmutVideoWidget.lock();
    if(m_pDatas[0] == nullptr)
    {
        qDebug()<<"m_pDatas[0] == nullptr";
    }

    if(m_iWidth*m_iHeight == 0)
    {
        qDebug()<<"m_iWidth*m_iHeight == 0";
    }

//    qDebug()<<" _pAVFrame->width==="<< _pAVFrame->width;
//    qDebug()<<" _pAVFrame->height==="<< _pAVFrame->height;

//    qDebug()<<" _pAVFrame->m_iWidth==="<< m_iWidth;
//    qDebug()<<" _pAVFrame->m_iHeight==="<< m_iHeight;

    if( _pAVFrame->width != m_iWidth || _pAVFrame->height != m_iHeight)
    {
        av_frame_free(&_pAVFrame);
        m_qmutVideoWidget.unlock();
        return;
    }

    if(m_iWidth == _pAVFrame->linesize[0]) //无需对齐
    {
        memcpy(m_pDatas[0], _pAVFrame->data[0], m_iWidth * m_iHeight);
        memcpy(m_pDatas[1], _pAVFrame->data[1], m_iWidth * m_iHeight / 4);
        memcpy(m_pDatas[2], _pAVFrame->data[2], m_iWidth * m_iHeight / 4);
    }
    else   //解决行对齐问题
    {
        for(int i = 0; i< m_iHeight; i++) //Y
        {
            memcpy(m_pDatas[0] + m_iWidth * i, _pAVFrame->data[0] + _pAVFrame->linesize[0] * i, m_iWidth);
        }

        for(int i = 0; i< m_iHeight / 2; i++) //U
        {
            memcpy(m_pDatas[1] + m_iWidth/2 * i, _pAVFrame->data[1] + _pAVFrame->linesize[1] * i, m_iWidth);
        }

        for(int i = 0; i< m_iHeight / 2; i++)  //V
        {
            memcpy(m_pDatas[2] + m_iWidth/2 * i, _pAVFrame->data[2] + _pAVFrame->linesize[2] * i, m_iWidth);
        }
    }
    m_qmutVideoWidget.unlock();

    av_frame_free(&_pAVFrame);

    //刷新显示
    update();
}

void XVideoWidget::initializeGL()
{
    qDebug()<<"initializeGL";

    m_qmutVideoWidget.lock();

    //初始化OpenGL （QOpenGLFunctions继承）函数
    initializeOpenGLFunctions();

    //加载片源Shader和顶点Shader
    m_QGLShaderProgram.addShaderFromSourceCode(QGLShader::Fragment, tString);
    m_QGLShaderProgram.addShaderFromSourceCode(QGLShader::Vertex, vString);

    //设置顶点坐标的变量
    m_QGLShaderProgram.bindAttributeLocation("vertexIn", A_VER);

    //设置材质坐标
    m_QGLShaderProgram.bindAttributeLocation("textureIn", T_VER);

    //编译shader
    m_QGLShaderProgram.link();

    //绑定shader
    m_QGLShaderProgram.bind();

    //传递顶点和材质坐标
    //顶点
    static const GLfloat ver[] =
    {
        -1.0f, -1.0f,
         1.0f, -1.0f,
        -1.0f,  1.0f,
         1.0f,  1.0f
    };

    //材质
    static const GLfloat tex[] =
    {
        0.0f, 1.0f,
        1.0f, 1.0f,
        0.0f, 0.0f,
        1.0f, 0.0f
    };

    //顶点
    glVertexAttribPointer(A_VER, 2, GL_FLOAT, 0, 0, ver);
    glEnableVertexAttribArray(A_VER);

    //材质
    glVertexAttribPointer(T_VER, 2, GL_FLOAT, 0, 0, tex);
    glEnableVertexAttribArray(T_VER);

    //从shader获取材质
    unis[0] = m_QGLShaderProgram.uniformLocation("tex_y");
    unis[1] = m_QGLShaderProgram.uniformLocation("tex_u");
    unis[2] = m_QGLShaderProgram.uniformLocation("tex_v");

    m_qmutVideoWidget.unlock();
}

void XVideoWidget::resizeGL(int _iWidget, int _iHeight)
{
    if(_iWidget * _iHeight <= 0)
    {
        return;
    }

    qDebug()<<"ReSizeOpenGL"<<_iWidget<<_iHeight;
}

void XVideoWidget::paintGL()
{
    m_qmutVideoWidget.lock();
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D, texs[0]); //0层绑定到Y材质
                                           //修改材质内容(复制内存内容)
    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, m_iWidth, m_iHeight, GL_RED, GL_UNSIGNED_BYTE, m_pDatas[0]);
    //与shader uni遍历关联
    glUniform1i(unis[0], 0);


    glActiveTexture(GL_TEXTURE0 + 1);
    glBindTexture(GL_TEXTURE_2D, texs[1]); //1层绑定到U材质
                                           //修改材质内容(复制内存内容)
    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, m_iWidth / 2, m_iHeight / 2, GL_RED, GL_UNSIGNED_BYTE, m_pDatas[1]);
    //与shader uni遍历关联
    glUniform1i(unis[1], 1);


    glActiveTexture(GL_TEXTURE0 + 2);
    glBindTexture(GL_TEXTURE_2D, texs[2]); //2层绑定到V材质
                                           //修改材质内容(复制内存内容)
    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, m_iWidth / 2, m_iHeight / 2, GL_RED, GL_UNSIGNED_BYTE, m_pDatas[2]);
    //与shader uni遍历关联
    glUniform1i(unis[2], 2);

    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
    //qDebug() << "paintGL";
    m_qmutVideoWidget.unlock();
}