console.log("loading transform system");

const transform =
      (entity,
       transformData = { x: {x: 1, y:0}, y: {x:0, y:1}, o: {x:0,y:0}}
      ) => {
          let {x, y, o} = transformData;
          let transform = [x.x, x.y, y.x, y.y, o.x, o.y];
          const updateEntity = () => {
              entity.dataset.transform = JSON.stringify (transform);
          };

          // these may be pulled out in the future into a separate renderer
          const setEntityStyleFromTransform = (entity) => {
              entity.style.transform =
                  `matrix(${entity.dataset.transform.replace(/\[|\]/g,'')})`;
          };
          const renderEntity = () => setEntityStyleFromTransform (entity);

          return (message, ...messageArgs) => {
              switch (message) {
              case "origin": {
                  return [transform[4], transform[5]];
              }
              case "x": {
                  return [transform[0], transform[1]];
              }
              case "y": {
                  return [transform[2], transform [3]];
              }
              case "translate": {
                  let [xTranslation, yTranslation] = messageArgs [0];
                  transform [4] += xTranslation;
                  transform [5] += yTranslation;
                  break;
              }
              }
              updateEntity ();
              renderEntity ();
          };
};

const initTransformSystem = (engine) => {
    engine("registerComponentType", "transform", transform);
};


// transform needs to actually provide transformation utilities