/**
  * {@inheritdoc}
  */
 public function getChart($chartIdentifier, DateTime $edd, ImageConfig $imageConfig)
 {
     $url = $this->buildQuery(sprintf('/api/Storage/Chart/%s/', $chartIdentifier), array('EDD' => $edd->format('Y-m-d'), 'ImageConfig' => array('Greyscale' => $imageConfig->getGreyscale() ? 'true' : 'false', 'ShowExtraCentiles' => $imageConfig->getShowExtraCentiles() ? 'true' : 'false', 'GridlinesByWeight' => $imageConfig->getGridlinesByWeight() ? 'true' : 'false', 'ScalePercent' => (int) $imageConfig->getScalePercent())));
     $data = $this->doRequest($url);
     return Chart::createFromJson($data)->setChartIdentifier($chartIdentifier);
 }