aitherboard/src/lib/services/auth/relay-list-fetcher.ts

/**
 * Relay list fetcher (kind 10002 and 10432)
 */

import { nostrClient } from '../nostr/nostr-client.js';
import { config } from '../nostr/config.js';
import type { NostrEvent } from '../../types/nostr.js';

export interface RelayInfo {
  url: string;
  read: boolean;
  write: boolean;
}

/**
 * Parse relay list from event
 */
export function parseRelayList(event: NostrEvent): RelayInfo[] {
  const relays: RelayInfo[] = [];

  for (const tag of event.tags) {
    if (tag[0] === 'r' && tag[1]) {
      const url = tag[1];
      const markers = tag.slice(2);

      // If no markers, relay is both read and write
      if (markers.length === 0) {
        relays.push({ url, read: true, write: true });
        continue;
      }

      // Check for explicit markers
      const hasRead = markers.includes('read');
      const hasWrite = markers.includes('write');

      // If only 'read' marker: read=true, write=false
      // If only 'write' marker: read=false, write=true
      // If both or neither explicitly: both true (default behavior)
      const read = hasRead || (!hasRead && !hasWrite);
      const write = hasWrite || (!hasRead && !hasWrite);

      relays.push({ url, read, write });
    }
  }

  return relays;
}

/**
 * Fetch relay lists for a pubkey (kind 10002 and 10432)
 */
export async function fetchRelayLists(
  pubkey: string,
  relays?: string[]
): Promise<{
  inbox: string[];
  outbox: string[];
}> {
  const relayList = relays || [
    ...config.defaultRelays,
    ...config.profileRelays
  ];

  // Fetch both kind 10002 and 10432
  const events = await nostrClient.fetchEvents(
    [
      { kinds: [10002], authors: [pubkey], limit: 1 },
      { kinds: [10432], authors: [pubkey], limit: 1 }
    ],
    relayList,
    { useCache: true, cacheResults: true }
  );

  const inbox: string[] = [];
  const outbox: string[] = [];

  for (const event of events) {
    const relayInfos = parseRelayList(event);
    for (const info of relayInfos) {
      if (info.read && !inbox.includes(info.url)) {
        inbox.push(info.url);
      }
      if (info.write && !outbox.includes(info.url)) {
        outbox.push(info.url);
      }
    }
  }

  // Deduplicate
  return {
    inbox: [...new Set(inbox)],
    outbox: [...new Set(outbox)]
  };
}