mrmBot-Matrix/natives/mirror.cc

#include <Magick++.h>
#include <napi.h>

#include <list>

using namespace std;
using namespace Magick;

Napi::Value Mirror(const Napi::CallbackInfo &info) {
  Napi::Env env = info.Env();

  Napi::Object obj = info[0].As<Napi::Object>();
  string path = obj.Get("path").As<Napi::String>().Utf8Value();
  bool vertical = obj.Has("vertical")
                      ? obj.Get("vertical").As<Napi::Boolean>().Value()
                      : false;
  bool first =
      obj.Has("first") ? obj.Get("first").As<Napi::Boolean>().Value() : false;
  string type = obj.Get("type").As<Napi::String>().Utf8Value();
  int delay =
      obj.Has("delay") ? obj.Get("delay").As<Napi::Number>().Int32Value() : 0;

  Blob blob;

  list<Image> frames;
  list<Image> coalesced;
  list<Image> mid;
  MagickCore::GravityType gravity;
  readImages(&frames, path);
  coalesceImages(&coalesced, frames.begin(), frames.end());

  if (vertical && first) {
    gravity = Magick::NorthGravity;
  } else if (!vertical && first) {
    gravity = Magick::WestGravity;
  } else if (vertical && !first) {
    gravity = Magick::SouthGravity;
  } else {
    gravity = Magick::EastGravity;
  }

  for (Image &image : coalesced) {
    list<Image> mirrored;
    Image final;
    image.extent(
        Geometry(to_string(vertical ? image.baseColumns()
                                    : image.baseColumns() / 2) +
                 "x" +
                 to_string(vertical ? image.baseRows() / 2 : image.baseRows())),
        gravity);
    mirrored.push_back(image);
    Image mirror = image;
    if (vertical) {
      mirror.flip();
    } else {
      mirror.flop();
    }
    if (first) {
      mirrored.push_back(mirror);
    } else {
      mirrored.push_front(mirror);
    }
    appendImages(&final, mirrored.begin(), mirrored.end(), vertical);
    final.repage();
    final.magick(type);
    final.animationDelay(delay == 0 ? image.animationDelay() : delay);
    mid.push_back(final);
  }

  optimizeTransparency(mid.begin(), mid.end());

  if (type == "gif") {
    for (Image &image : mid) {
      image.quantizeDither(false);
      image.quantize();
    }
  }

  writeImages(mid.begin(), mid.end(), &blob);

  Napi::Object result = Napi::Object::New(env);
  result.Set("data",
          Napi::Buffer<char>::Copy(env, (char *)blob.data(), blob.length()));
  result.Set("type", type);
  return result;
}