/* @flow */

import { InterfaceTypeComposer, type SchemaComposer } from 'graphql-compose';

const NodeTC = InterfaceTypeComposer.createTemp({
  name: 'Node',
  description: 'An object, that can be fetched by the globally unique ID among all types.',
  fields: {
    id: {
      type: 'ID!',
      description: 'The globally unique ID among all types.',
    },
  },
  resolveType: payload => {
    // `payload.__nodeType` was added to payload via nodeFieldConfig.resolve
    return payload.__nodeType ? payload.__nodeType : null;
  },
});

export const NodeInterface = NodeTC.getType();

export function getNodeInterface<TContex>(
  sc: SchemaComposer<TContex>
): InterfaceTypeComposer<any, TContex> {
  if (sc.hasInstance('Node', InterfaceTypeComposer)) {
    return (sc.get('Node'): any);
  }
  sc.set('Node', (NodeTC: any));
  return (NodeTC: any);
}