#include <opencv2/opencv.hpp>
#include <Magick++.h> 
#include <iostream> 

using namespace std; 
using namespace Magick; 
using namespace cv;
// imageMagick installation on Mac OSX: https://www.sethvargo.com/install-imagemagick-on-osx-lion/
// read gif's first frame to cv::Mat https://stackoverflow.com/questions/41841553/convert-magickimage-to-cvmat
// ref link: https://imagemagick.org/discourse-server/viewtopic.php?t=35080
// compile: g++ test_gif.cpp `pkg-config --cflags opencv` `pkg-config --libs opencv` `pkg-config --cflags magick++` `pkg-config --libs magick++`

cv::Mat Magick2Mat(Image& image){
    // Get dimensions of Magick++ Image
    int w = image.columns();
    int h = image.rows();
    // Make OpenCV Mat of same size with 8-bit and 3 channels
    Mat opencvImage(h,w,CV_8UC3);
    // Unpack Magick++ pixels into OpenCV Mat structure
    image.write(0,0,w,h,"BGR",Magick::CharPixel,opencvImage.data);
    return opencvImage;
}

Magick::Image Mat2Magick(Mat& src){
    if(src.channels()==4) {
        Image mgk(src.cols, src.rows, "BGRA", CharPixel, (char *)src.data);
        return mgk;
    }
    if(src.channels()==3){
        cvtColor(src,src,cv::COLOR_BGR2BGRA);
        Image mgk(src.cols, src.rows, "BGRA", CharPixel, (char *)src.data);
        return mgk;
    }
    if(src.channels()==1) {
        cvtColor(src,src,cv::COLOR_GRAY2BGR);
        cvtColor(src,src,cv::COLOR_BGR2BGRA);
        Image mgk(src.cols, src.rows, "BGRA", CharPixel, (char *)src.data);
        return mgk;
    }
}

int main(int argc,char **argv){ 
    // Initialise ImageMagick library
    // InitializeMagick(*argv);
    InitializeMagick("");
    
    // Create Magick++ Image object and read image file
    list<Image> imageList;
    readImages(&imageList, "sample.gif");
    
    list<cv::Mat> newList;
    for(list<Image>::iterator it = imageList.begin(); it != imageList.end(); it++){
        Mat tmp = Magick2Mat(*it);
        newList.push_back(tmp);
    }
    cout << newList.size() << endl;
    // writeImages(newList.begin(),newList.end(),"tmp/new_image.miff");
    
    for(list<cv::Mat>::iterator it = newList.begin(); it!=newList.end(); it++){
        cv::imshow("GIF", *it);
        // cv::waitKey(0);
    }
    cv::waitKey(0);
    cv::destroyAllWindows();

    // Save opencvImage
    // imwrite("result.png", opencvImage);
    return 0;
}