export type RdfNode = RdfIri | RdfLiteral | RdfBlank;

export interface RdfIri {
  type: "uri";
  value: string;
}

export interface RdfBlank {
  type: "bnode";
  value: string;
}

export interface RdfLiteral {
  type: "literal";
  value: string;
  datatype?: string;
  "xml:lang": string;
}

export interface Triple {
  subject: RdfNode;
  predicate: RdfNode;
  object: RdfNode;
}

export function isRdfBlank(e: RdfNode): e is RdfBlank {
  return e && e.type === "bnode";
}

export function isRdfIri(e: RdfNode): e is RdfIri {
  return e && e.type === "uri";
}

export function isRdfLiteral(e: RdfNode): e is RdfLiteral {
  return e && e.type === "literal";
}

export interface BlankBinding extends ElementBinding {
  blankType: {
    value: "listHead" | "blankNode";
  };
  blankTrgProp: RdfNode;
  blankTrg: RdfNode;
  blankSrc?: RdfNode;
  blankSrcProp?: RdfNode;
  newInst?: RdfIri | RdfBlank;
}

export function isBlankBinding(
  binding: ElementBinding | BlankBinding
): binding is BlankBinding {
  const blank = binding as BlankBinding;
  return (
    blank.blankTrgProp !== undefined ||
    blank.blankTrg !== undefined ||
    blank.blankSrcProp !== undefined ||
    blank.blankSrc !== undefined
  );
}

export interface ElementBinding {
  inst: RdfIri | RdfBlank;
  class?: RdfIri;
  label?: RdfLiteral;
  propType?: RdfIri;
  propValue?: RdfIri | RdfLiteral;
}

export interface ClassBinding {
  class: RdfIri;
  instcount?: RdfLiteral;
  label?: RdfLiteral;
  parent?: RdfIri;
}

export interface PropertyBinding {
  property: RdfIri;
  label?: RdfLiteral;
}

export interface LinkBinding {
  source: RdfIri | RdfBlank;
  type: RdfIri;
  target: RdfIri | RdfBlank;
  propType?: RdfIri;
  propValue?: RdfLiteral;
}

export interface LinkCountBinding {
  link: RdfIri | RdfBlank;
  inCount: RdfLiteral;
  outCount: RdfLiteral;
}

export interface LinkTypeBinding {
  link: RdfIri;
  label?: RdfLiteral;
  instcount?: RdfLiteral;
}

export interface ElementImageBinding {
  inst: RdfIri;
  linkType: RdfIri;
  image: RdfIri;
}

export interface ElementTypeBinding {
  inst: RdfIri;
  class: RdfIri;
}

export interface FilterBinding {
  classAll?: RdfIri;
  link?: RdfIri;
  direction?: RdfLiteral;
}

export interface SparqlResponse<Binding> {
  head: { vars: string[] };
  results: { bindings: Binding[] };
}