#include "opencv2/calib3d/calib3d.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/core/utility.hpp"
#include <iostream>
#include <stdio.h>
#include <string>
using namespace cv;

void testfunc()
{
    using namespace std;
    using namespace cv;
    Mat large = imread("E:/work/working_folder/2hRcBDV.jpg");
    Mat rgb;
    if (large.rows > 2500 || large.cols > 1250)
    {
        pyrDown(large, rgb);
    }
    else
    {
        rgb = large.clone();
    }
    cv::Mat smallx;
    cvtColor(rgb, smallx, CV_BGR2GRAY);
    Mat grad, connected, bw;

    Mat morphKernel = getStructuringElement(MORPH_ELLIPSE, Size(3, 3));
    cv::morphologyEx(smallx, grad, MORPH_GRADIENT, morphKernel);
    cv::threshold(grad, bw, 100, 255, THRESH_BINARY + THRESH_OTSU);
    morphKernel = getStructuringElement(MORPH_RECT, Size(9, 1));
    cv::morphologyEx(bw, connected, MORPH_CLOSE, morphKernel);

    Mat mask = Mat::zeros(bw.size(), CV_8UC1);
    vector<vector<Point>> contours;
    vector<Vec4i> hierarchy;
    imshow("connected", connected);
    cv::waitKey();

    cv::findContours(connected, contours, hierarchy, CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE, Point(0, 0));
}

static void print_help()
{
    printf("\nDemo stereo matching converting L and R images into disparity and point clouds\n");
    printf("\nUsage: stereo_match <left_image> <right_image> [--algorithm=bm|sgbm|hh|sgbm3way] [--blocksize=<block_size>]\n"
        "[--max-disparity=<max_disparity>] [--scale=scale_factor>] [-i=<intrinsic_filename>] [-e=<extrinsic_filename>]\n"
        "[--no-display] [-o=<disparity_image>] [-p=<point_cloud_file>]\n");
}

static void saveXYZ(const char* filename, const Mat& mat)
{
    const double max_z = 1e4;
    FILE* fp = fopen(filename, "wt");
    for (int y = 0; y < mat.rows; y++)
    {
        for (int x = 0; x < mat.cols; x++)
        {
            Vec3f point = mat.at<Vec3f>(y, x);
            if (fabs(point[2] - max_z) < FLT_EPSILON || fabs(point[2]) > max_z) continue;
            fprintf(fp, "%f %f %f\n", point[0], point[1], point[2]);
        }
    }
    fclose(fp);
}

int main(int argc, char** argv)
{

    //testfunc();
    std::string img1_filename = "E:/work/working_folder/cam_1_01.bmp";
    std::string img2_filename = "E:/work/working_folder/cam_2_01.bmp";
    std::string intrinsic_filename = "E:/work/working_folder/intrinsics.yml";
    std::string extrinsic_filename = "E:/work/working_folder/extrinsics.yml";
    std::string disparity_filename = "E:/work/working_folder/SBM_sample.png";
    std::string point_cloud_filename = "E:/work/working_folder/xyz.txt";

    enum { STEREO_BM = 0, STEREO_SGBM = 1, STEREO_HH = 2, STEREO_VAR = 3, STEREO_3WAY = 4 };
    int alg = STEREO_BM;
    int SADWindowSize, numberOfDisparities;
    bool no_display;
    float scale;

    Ptr<StereoBM> bm = StereoBM::create(16, 9);
    Ptr<StereoSGBM> sgbm = StereoSGBM::create(0, 16, 3);
    /*cv::CommandLineParser parser(argc, argv,
        "{@arg1||}{@arg2||}{help h||}{algorithm||}{max-disparity|0|}{blocksize|0|}{no-display||}{scale|1|}{i||}{e||}{o||}{p||}");
    if (parser.has("help"))
    {
        print_help();
        return 0;
    }
    img1_filename = parser.get<std::string>(0);
    img2_filename = parser.get<std::string>(1);
    if (parser.has("algorithm"))
    {
        std::string _alg = parser.get<std::string>("algorithm");
        alg = _alg == "bm" ? STEREO_BM :
            _alg == "sgbm" ? STEREO_SGBM :
            _alg == "hh" ? STEREO_HH :
            _alg == "var" ? STEREO_VAR :
            _alg == "sgbm3way" ? STEREO_3WAY : -1;
    }
    numberOfDisparities = parser.get<int>("max-disparity");
    SADWindowSize = parser.get<int>("blocksize");
    scale = parser.get<float>("scale");
    no_display = parser.has("no-display");
    if (parser.has("i"))
        intrinsic_filename = parser.get<std::string>("i");
    if (parser.has("e"))
        extrinsic_filename = parser.get<std::string>("e");
    if (parser.has("o"))
        disparity_filename = parser.get<std::string>("o");
    if (parser.has("p"))
        point_cloud_filename = parser.get<std::string>("p");
    if (!parser.check())
    {
        parser.printErrors();
        return 1;
    }
    if (alg < 0)
    {
        printf("Command-line parameter error: Unknown stereo algorithm\n\n");
        print_help();
        return -1;
    }
    if (numberOfDisparities < 1 || numberOfDisparities % 16 != 0)
    {
        printf("Command-line parameter error: The max disparity (--maxdisparity=<...>) must be a positive integer divisible by 16\n");
        print_help();
        return -1;
    }
    if (scale < 0)
    {
        printf("Command-line parameter error: The scale factor (--scale=<...>) must be a positive floating-point number\n");
        return -1;
    }
    if (SADWindowSize < 1 || SADWindowSize % 2 != 1)
    {
        printf("Command-line parameter error: The block size (--blocksize=<...>) must be a positive odd number\n");
        return -1;
    }
    if (img1_filename.empty() || img2_filename.empty())
    {
        printf("Command-line parameter error: both left and right images must be specified\n");
        return -1;
    }
    if ((!intrinsic_filename.empty()) ^ (!extrinsic_filename.empty()))
    {
        printf("Command-line parameter error: either both intrinsic and extrinsic parameters must be specified, or none of them (when the stereo pair is already rectified)\n");
        return -1;
    }

    if (extrinsic_filename.empty() && !point_cloud_filename.empty())
    {
        printf("Command-line parameter error: extrinsic and intrinsic parameters must be specified to compute the point cloud\n");
        return -1;
    }

    int color_mode = alg == STEREO_BM ? 0 : -1;
    */

    Mat img1 = imread(img1_filename, IMREAD_GRAYSCALE);
    Mat img2 = imread(img2_filename, IMREAD_GRAYSCALE);
    //cv::resize(img1, img1, cv::Size(), 0.25, 0.25);
    //cv::resize(img2, img2, cv::Size(), 0.25, 0.25);

    if (img1.empty())
    {
        printf("Command-line parameter error: could not load the first input image file\n");
        return -1;
    }
    if (img2.empty())
    {
        printf("Command-line parameter error: could not load the second input image file\n");
        return -1;
    }
    scale = 1;
    if (scale != 1.f)
    {
        Mat temp1, temp2;
        int method = scale < 1 ? INTER_AREA : INTER_CUBIC;
        resize(img1, temp1, Size(), scale, scale, method);
        img1 = temp1;
        resize(img2, temp2, Size(), scale, scale, method);
        img2 = temp2;
    }

    Size img_size = img1.size();

    Rect roi1, roi2;

    Mat Q;

    if (!intrinsic_filename.empty())
    {
        // reading intrinsic parameters
        FileStorage fs(intrinsic_filename, FileStorage::READ);
        if (!fs.isOpened())
        {
            printf("Failed to open file %s\n", intrinsic_filename.c_str());
            return -1;
        }

        Mat M1, D1, M2, D2;
        fs["M1"] >> M1;
        fs["D1"] >> D1;
        fs["M2"] >> M2;
        fs["D2"] >> D2;

        M1 *= scale;
        M2 *= scale;

        fs.open(extrinsic_filename, FileStorage::READ);
        if (!fs.isOpened())
        {
            printf("Failed to open file %s\n", extrinsic_filename.c_str());
            return -1;
        }

        std::cout << "<M1 : " << std::endl;
        std::cout << M1.size() << std::endl;
        std::cout << M1.type() << std::endl;
        for (int i = 0; i < 3; i++)
        {
            for (int j = 0; j < 3; j++)
            {
                std::cout << M1.at<double>(i, j) << " ";
            }
            std::cout << std::endl;
        }
        std::cout << "<M2 : " << std::endl;
        std::cout << M2.size() << std::endl;
        std::cout << M2.type() << std::endl;

        for (int i = 0; i < 3; i++)
        {
            for (int j = 0; j < 3; j++)
            {
                std::cout << M2.at<double>(i, j) << " ";
            }
            std::cout << std::endl;
        }
        Mat R, T, R1, P1, R2, P2;
        fs["R"] >> R;
        fs["T"] >> T;
        fs["R1"] >> R1;
        fs["P1"] >> P1;
        fs["R2"] >> R2;
        fs["P2"] >> P2;
        fs["Q"] >> Q;
        stereoRectify(M1, D1, M2, D2, img_size, R, T, R1, R2, P1, P2, Q, CV_CALIB_ZERO_DISPARITY, -1, img_size, &roi1, &roi2);
        Mat map11, map12, map21, map22;
        initUndistortRectifyMap(M1, D1, R1, P1, img_size, CV_16SC2, map11, map12);
        initUndistortRectifyMap(M2, D2, R2, P2, img_size, CV_16SC2, map21, map22);

        Mat img1r, img2r;
        remap(img1, img1r, map11, map12, INTER_LINEAR);
        remap(img2, img2r, map21, map22, INTER_LINEAR);
        img1 = img1r;
        img2 = img2r; // images lay together, so there is no disparity at all
    }

    numberOfDisparities = 16 * 10;
    SADWindowSize = 15;
    numberOfDisparities = numberOfDisparities > 0 ? numberOfDisparities : ((img_size.width / 8) + 15) & -16;

    bm->setROI1(roi1);
    bm->setROI2(roi2);
    bm->setPreFilterCap(31);
    bm->setBlockSize(SADWindowSize > 0 ? SADWindowSize : 9);
    bm->setMinDisparity(0);
    bm->setNumDisparities(numberOfDisparities);
    bm->setTextureThreshold(10);
    bm->setUniquenessRatio(15);
    bm->setSpeckleWindowSize(100);
    bm->setSpeckleRange(32);
    bm->setDisp12MaxDiff(1);



    sgbm->setPreFilterCap(63);
    int sgbmWinSize = SADWindowSize > 0 ? SADWindowSize : 3;
    sgbm->setBlockSize(sgbmWinSize);

    int cn = img1.channels();
    sgbm->setP1(8 * cn*sgbmWinSize*sgbmWinSize);
    sgbm->setP2(32 * cn*sgbmWinSize*sgbmWinSize);
    sgbm->setMinDisparity(0);
    sgbm->setNumDisparities(numberOfDisparities);
    sgbm->setUniquenessRatio(10);
    sgbm->setSpeckleWindowSize(50);
    sgbm->setSpeckleRange(32);
    sgbm->setDisp12MaxDiff(1);
    if (alg == STEREO_HH)
        sgbm->setMode(StereoSGBM::MODE_HH);
    else if (alg == STEREO_SGBM)
        sgbm->setMode(StereoSGBM::MODE_SGBM);
    else if (alg == STEREO_3WAY)
        sgbm->setMode(StereoSGBM::MODE_SGBM_3WAY);

    Mat disp, disp8;
    //Mat img1p, img2p, dispp;
    //copyMakeBorder(img1, img1p, 0, 0, numberOfDisparities, 0, IPL_BORDER_REPLICATE);
    //copyMakeBorder(img2, img2p, 0, 0, numberOfDisparities, 0, IPL_BORDER_REPLICATE);

    int64 t = getTickCount();
    if (alg == STEREO_BM)
        bm->compute(img1, img2, disp);
    else if (alg == STEREO_SGBM || alg == STEREO_HH || alg == STEREO_3WAY)
        sgbm->compute(img1, img2, disp);
    t = getTickCount() - t;
    printf("Time elapsed: %fms\n", t * 1000 / getTickFrequency());

    //disp = dispp.colRange(numberOfDisparities, img1p.cols);
    if (alg != STEREO_VAR)
        disp.convertTo(disp8, CV_8U, 255 / (numberOfDisparities*16.));
    else
        disp.convertTo(disp8, CV_8U);
    no_display = false;
    if (!no_display)
    {
        namedWindow("left", 1);
        imshow("left", img1);
        namedWindow("right", 1);
        imshow("right", img2);
        namedWindow("disparity", 0);
        imshow("disparity", disp8);
        printf("press any key to continue...");
        fflush(stdout);
        waitKey(5000);
        printf("\n");
    }

    if (!disparity_filename.empty())
        imwrite(disparity_filename, disp8);

    if (!point_cloud_filename.empty())
    {
        printf("storing the point cloud...");
        fflush(stdout);
        Mat xyz;
        //disp.convertTo(disp, CV_32F);
        disp.convertTo(disp, CV_32F, 1 / 16.);
        //cv::normalize(disp, disp, 0, 16*10, NORM_MINMAX, CV_32F);

        std::cout << disp.type() << std::endl;
        std::cout << Q.type();
        Q.convertTo(Q, CV_32FC1);
        /*
        cv::Mat_<cv::Vec3f> XYZ(disp.rows, disp.cols);   // Output point cloud
        cv::Mat_<float> vec_tmp(4, 1);
        for (int y = 0; y<disp.rows; ++y) {
            for (int x = 0; x<disp.cols; ++x) {
                vec_tmp(0) = y; vec_tmp(1) = x; vec_tmp(2) = disp.at<float>(y, x); vec_tmp(3) = 1;
                vec_tmp = Q * vec_tmp;
                vec_tmp /= vec_tmp(3);
                cv::Vec3f &point = XYZ.at<cv::Vec3f>(y, x);
                point[0] = vec_tmp(0);
                point[1] = vec_tmp(1);
                point[2] = vec_tmp(2)/2;
            }
        }
        */
        reprojectImageTo3D(disp, xyz, Q, true, CV_32F);
        patchNaNs(xyz, 0);
        saveXYZ(point_cloud_filename.c_str(), xyz);

        printf("\n");
    }

    return 0;
}