const upsampleBilinear = (imageHeight: number, imageWidth: number) => {
  const kernel = {
    variableNames: ['p'],
    outputShape: [imageHeight, imageWidth],
    userCode: `
	  void main() {
	    ivec2 coords = getOutputCoords();
	    int j = coords[0];
	    int i = coords[1];

	    float sj = 0.5 * float(j) - 0.25; 
	    float si = 0.5 * float(i) - 0.25;

	    float sj0 = floor(sj);
	    float sj1 = ceil(sj);
	    float si0 = floor(si);
	    float si1 = ceil(si);

	    int sj0I = int(sj0);
	    int sj1I = int(sj1);
	    int si0I = int(si0);
	    int si1I = int(si1);

	    float sum = 0.0;
	    sum += getP(sj0I, si0I) * (si1 - si) * (sj1 - sj);
	    sum += getP(sj1I, si0I) * (si1 - si) * (sj - sj0);
	    sum += getP(sj0I, si1I) * (si - si0) * (sj1 - sj);
	    sum += getP(sj1I, si1I) * (si - si0) * (sj - sj0);
	    setOutput(sum);
	  }
	`,
  };

  return kernel;
};

export default upsampleBilinear;