teTo = null) {
  const { width: deviceWidth, height: deviceHeight } = device;
  const { width: viewportWidth, height: viewportHeight } = viewport;

  // Determine the primary orientation of the device screen.
  const primaryOrientation =
    deviceHeight >= deviceWidth ? PORTRAIT_PRIMARY : LANDSCAPE_PRIMARY;

  // Determine the current orientation of the device screen.
  const currentOrientation =
    viewportHeight >= viewportWidth ? PORTRAIT_PRIMARY : LANDSCAPE_PRIMARY;

  // Calculate the orientation angle of the device.
  let angle;

  if (typeof angleToRotateTo === "number") {
    angle = angleToRotateTo;
  } else if (currentOrientation !== primaryOrientation) {
    angle = 90;
  } else {
    angle = 0;
  }

  // Calculate the orientation type of the device.
  let orientationType = currentOrientation;

  // If the viewport orientation is different from the primary orientation and the angle
  // to rotate to is 0, then we are moving the device orientation back to its primary
  // orientation.
  if (currentOrientation !== primaryOrientation && angleToRotateTo === 0) {
    orientationType = primaryOrientation;
  } else if (angleToRotateTo === 90 || angleToRotateTo === 270) {
    if (currentOrientation.includes("portrait")) {
      orientationType = LANDSCAPE_PRIMARY;
    } else if (currentOrientation.includes("landscape")) {
      orientationType = PORTRAIT_PRIMARY;
    }
  }

  return {
    type: orientationType,
    angle,
  };
}

exports.getOrientation = getOrientation;
PK