BASE <https://graphcentric.com/>
PREFIX schema: <https://schema.org/>
PREFIX gcs: <https://graphcentric.com/schema/>
PREFIX dcterms: <http://purl.org/dc/terms/>

CONSTRUCT {
  ?_subject
    dcterms:title "Olney Church";
    gcs:image ?image.

  ?image
    a schema:ImageObject;
    schema:name ?imageName;
    schema:description ?altText;
    schema:caption ?caption;
    schema:contentUrl ?image;
    schema:creator ?creator.

  ?creator
    a schema:Person;
    schema:name ?creatorName.
}
WHERE {
  BIND(<media/decks/access-control/olney-church.jpg> AS ?image)
  BIND("Olney church photo" AS ?altText)

  GRAPH <graphs/internal-decks> {
    ?image schema:name ?imageName.
    OPTIONAL { ?image schema:creator ?creator. }
    OPTIONAL { ?image schema:creditText ?creditText. }
  }

  OPTIONAL {
    FILTER(BOUND(?creator))
    GRAPH <graphs/cms> {
      ?creator schema:name ?creatorName.
    }
  }

  BIND(IF(BOUND(?creatorName), CONCAT("Photo: ", ?creatorName), ?creditText) AS ?caption)
}