mrmBot-Matrix/natives/meme.cc

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

#include <list>

using namespace std;
using namespace Magick;

Napi::Value Meme(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();
  string top = obj.Get("top").As<Napi::String>().Utf8Value();
  string bottom = obj.Get("bottom").As<Napi::String>().Utf8Value();
  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;
  Image top_text;
  Image bottom_text;
  readImages(&frames, path);
  coalesceImages(&coalesced, frames.begin(), frames.end());
  for_each(coalesced.begin(), coalesced.end(), scaleImage(Geometry(600, 600)));

  top_text.size(Geometry(to_string(coalesced.front().columns())));
  top_text.backgroundColor("none");
  top_text.font("Impact");
  top_text.fontPointsize(40);
  top_text.textGravity(Magick::CenterGravity);
  top_text.read("pango:<span foreground='white'>" + top + "</span>");
  Image top_text_fill = top_text;
  top_text_fill.channel(Magick::AlphaChannel);
  top_text_fill.morphology(Magick::EdgeOutMorphology, "Octagon");
  top_text_fill.backgroundColor("black");
  top_text_fill.alphaChannel(Magick::ShapeAlphaChannel);
  top_text.composite(top_text_fill, Magick::CenterGravity,
                     Magick::DstOverCompositeOp);

  if (bottom != "") {
    bottom_text.size(Geometry(to_string(coalesced.front().columns())));
    bottom_text.backgroundColor("none");
    bottom_text.font("Impact");
    bottom_text.fontPointsize(40);
    bottom_text.textGravity(Magick::CenterGravity);
    bottom_text.read("pango:<span foreground='white'>" + bottom + "</span>");
    Image bottom_text_fill = bottom_text;
    bottom_text_fill.channel(Magick::AlphaChannel);
    bottom_text_fill.morphology(Magick::EdgeOutMorphology, "Octagon");
    bottom_text_fill.backgroundColor("black");
    bottom_text_fill.alphaChannel(Magick::ShapeAlphaChannel);
    bottom_text.composite(bottom_text_fill, Magick::CenterGravity,
                          Magick::DstOverCompositeOp);
  }

  for (Image &image : coalesced) {
    image.composite(top_text, Magick::NorthGravity, Magick::OverCompositeOp);
    if (bottom != "")
      image.composite(bottom_text, Magick::SouthGravity,
                      Magick::OverCompositeOp);
    image.magick(type);
    mid.push_back(image);
  }

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

  if (type == "gif") {
    for (Image &image : mid) {
      image.quantizeDither(false);
      image.quantize();
      if (delay != 0) image.animationDelay(delay);
    }
  }

  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;
}