#include "GBenchMark.h"
#include <fstream>
#include <cmath> 
GBenchMark::GBenchMark(int width, int height) : mWidth(width), mHeight(height)
{
    std::shared_ptr<gcanvas::GCanvas> p(new gcanvas::GCanvas("benchMark", {true, true}, nullptr));
    this->mCanvas = p;
}

void GBenchMark::intilGLOffScreenEnviroment()
{
#ifdef CONTEXT_ES20
    EGLint ai32ContextAttribs[] = {EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE};
#endif

    // Step 1 - Get the default display.
    EGLDisplay eglDisplay = eglGetDisplay((EGLNativeDisplayType)0);

    // Step 2 - Initialize EGL.
    eglInitialize(eglDisplay, 0, 0);

#ifdef CONTEXT_ES20
    // Step 3 - Make OpenGL ES the current API.
    eglBindAPI(EGL_OPENGL_ES_API);

    // Step 4 - Specify the required configuration attributes.
    EGLint pi32ConfigAttribs[5];
    pi32ConfigAttribs[0] = EGL_SURFACE_TYPE;
    pi32ConfigAttribs[1] = EGL_WINDOW_BIT;
    pi32ConfigAttribs[2] = EGL_RENDERABLE_TYPE;
    pi32ConfigAttribs[3] = EGL_OPENGL_ES2_BIT;
    pi32ConfigAttribs[4] = EGL_NONE;
#else
    EGLint pi32ConfigAttribs[3];
    pi32ConfigAttribs[0] = EGL_SURFACE_TYPE;
    pi32ConfigAttribs[1] = EGL_WINDOW_BIT;
    pi32ConfigAttribs[2] = EGL_NONE;
#endif

    // Step 5 - Find a config that matches all requirements.
    int iConfigs;
    EGLConfig eglConfig;
    eglChooseConfig(eglDisplay, pi32ConfigAttribs, &eglConfig, 1,
                    &iConfigs);

    if (iConfigs != 1)
    {
        printf("Error: eglChooseConfig(): config not found \n");
        exit(-1);
    }

    // Step 6 - Create a surface to draw to.
    EGLSurface eglSurface;
    // eglSurface = eglCreateWindowSurface(eglDisplay, eglConfig,  (EGLNativeWindowType)NULL, NULL);
    eglSurface = eglCreatePbufferSurface(eglDisplay, eglConfig, NULL);
    // Step 7 - Create a context.
    EGLContext eglContext;
#ifdef CONTEXT_ES20
    eglContext = eglCreateContext(eglDisplay, eglConfig, NULL, ai32ContextAttribs);
#else
    eglContext = eglCreateContext(eglDisplay, eglConfig, NULL, NULL);
#endif

    // Step 8 - Bind the context to the current thread
    eglMakeCurrent(eglDisplay, eglSurface, eglSurface, eglContext);
    // end of standard gl context setup

    // Step 9 - create framebuffer object
    GLuint fboId = 0;
    // p->Clear();
    // glClearColor(255,255,255,255);
    // create a framebuffer objec g++  testopengloffscreen.cc lodepng.cc  -lGLESv2 -lglfw -lEGLt
    glGenFramebuffers(1, &fboId);
    glBindFramebuffer(GL_FRAMEBUFFER, fboId);

    GLuint renderBuffer;
    glGenRenderbuffers(1, &renderBuffer);
    glBindRenderbuffer(GL_RENDERBUFFER, renderBuffer);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_RGB565, mWidth, mHeight);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, renderBuffer);
    GLuint depthRenderbuffer;
    glGenRenderbuffers(1, &depthRenderbuffer);
    glBindRenderbuffer(GL_RENDERBUFFER, depthRenderbuffer);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8_OES, mWidth, mHeight);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthRenderbuffer);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, depthRenderbuffer);

    // check FBO status
    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
    if (status != GL_FRAMEBUFFER_COMPLETE)
    {
        printf("Problem with OpenGL framebuffer after specifying color render buffer: n%xn", status);
    }
    else
    {
        printf("FBO creation succeddedn \n ");
    }

    GLint format = 0, type = 0;
    glGetIntegerv(GL_IMPLEMENTATION_COLOR_READ_FORMAT, &format);
    glGetIntegerv(GL_IMPLEMENTATION_COLOR_READ_TYPE, &type);
    // this->initGcanvas();
}

void GBenchMark::initGcanvas()
{
    if (mCanvas)
    {
        mCanvas->CreateContext();
        mCanvas->OnSurfaceChanged(0, 0, mWidth, mHeight);
    }
}
void GBenchMark::render2file(std::string caseName)
{
    int size = 4 * mWidth * mHeight;
    unsigned char *data = new unsigned char[size];
    glReadPixels(0, 0, mWidth, mHeight, GL_RGBA, GL_UNSIGNED_BYTE, data);
    encodePixelsToFile(caseName + ".png", data, mWidth, mHeight);
    delete data;
}
float GBenchMark::computeRatioWithW3C(std::string caseName)
{
    std::vector<unsigned char> w3cImage;
    std::vector<unsigned char> gcanvasImage;

    decodeFile2Pixels(this->w3cPrefix + caseName + ".png", w3cImage);
    decodeFile2Pixels(caseName + ".png", gcanvasImage);
    int N = std::min(w3cImage.size(), gcanvasImage.size());
    int errorCount = 0;
    int correctCount = 0;
    if (N == 0)
        return 0.0;
    for (int i = 0; i < N; i++)
    {
        if (std::abs(w3cImage[i] - gcanvasImage[i])>15)
            errorCount++;
        else
            correctCount++;
    }
    return 1.0f * correctCount / N;
}

void GBenchMark::run(std::string caseName, std::function<void(std::shared_ptr<gcanvas::GCanvas> canvas, GCanvasContext *ctx, int width, int height)> drawFunc)
{
    std::shared_ptr<gcanvas::GCanvas> p(new gcanvas::GCanvas("benchMark", {true, true}, nullptr));
    p->CreateContext();
    p->OnSurfaceChanged(0, 0, mWidth, mHeight);
    p->Clear();
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT|GL_STENCIL_BUFFER_BIT);
    drawFunc(p, p->mCanvasContext, mWidth, mHeight);
    p->drawFrame();
    this->render2file(caseName);
    float ratio = this->computeRatioWithW3C(caseName);
    this->data.insert(std::make_pair(caseName, ratio));
}

void GBenchMark::dumpResult()
{
    std::ofstream myfile;
    myfile.open("result.txt");
    myfile << "CaseName";
    myfile << " ";
    myfile << "Ratio";
    myfile << " ";
    myfile << "Result";
    myfile << "\n";
    int unpassCounter = 0;
    int passCounter = 0;
    for (auto it = data.begin(); it != data.end(); it++)
    {
        myfile << it->first;
        myfile << " ";
        myfile << it->second;
        myfile << " ";
        if (it->second > 0.97 && it->second <= 1.0f)
        {
            myfile << "pass";
            myfile << "\n";
            passCounter++;
        }
        else
        {
            myfile << "unpass";
            myfile << "\n";
            unpassCounter++;
        }
    }
    myfile << "total:" << data.size();
    myfile << " ";
    myfile << "pass_count:";
    myfile << passCounter;
    myfile << " ";
    myfile << "unpass_count:";
    myfile << unpassCounter;
    myfile << "\n";
    myfile.close();
}