/**
 * The discovery port over the local index. It answers the same question
 * Constellation answers, from records the appview indexed itself: which
 * records, in which accounts, name this repository at this path.
 *
 * Whoever answers can add noise or omit; they cannot forge a word, because
 * the caller reads each record from its author.
 */

import { linksOf } from './store.js';

/** One record about the subject, by its address. */
export { linksOf };

/**
 * @typedef {Object} DiscoveryPort
 * @property {(subjectUri: string, collection: string, path?: string) => Promise<{did: string, collection: string, rkey: string}[]>} about -
 *   every record of the collection naming the subject at the path, which is
 *   `subject.uri` unless given.
 */

/**
 * @param {import('./store.js').AppViewStore} store
 * @returns {DiscoveryPort}
 */
export function createIndexedDiscovery(store) {
  return {
    async about(subjectUri, collection, path = 'subject.uri') {
      const rows = store.about(subjectUri, collection, path);
      return rows.map((row) => ({
        did: row.did,
        collection: row.collection,
        rkey: row.rkey,
      }));
    },
  };
}