/**
 * Extra personal NIP-05 handles for a profile.
 *
 * A kind-0 profile has ONE standard `nip05` field, and other clients editing it
 * may drop anything non-standard. So the extra handles live in a **separate
 * NIP-78 record** (kind 30078, `d=skatespots:profile-handles`) authored by the
 * user — the primary stays in `nip05` (works everywhere), the extras ride here
 * (SkateSpots-only, but durable against another client re-saving the profile).
 *
 * Each handle must resolve (via `/.well-known/nostr.json`) to the **owner's own**
 * pubkey — verified the same way as a crew handle, just against the profile key.
 */
import { APP_DATA_KIND } from '@/lib/types';

export { APP_DATA_KIND };

/** `d` identifier for the per-user extra-handles record. */
export const PROFILE_HANDLES_D = 'skatespots:profile-handles';

export const MAX_PROFILE_HANDLES = 5;

/** `local@domain.tld` per NIP-05 (local part is `[a-z0-9-_.]`). */
export const NIP05_HANDLE_RE = /^[a-z0-9\-_.]+@[a-z0-9.-]+\.[a-z]{2,}$/;

/** Normalise a raw handle; returns null when it isn't a valid `local@domain`. */
export function normalizeHandle(raw: string): string | null {
  const value = raw.trim().toLowerCase();
  return NIP05_HANDLE_RE.test(value) ? value : null;
}

/** All extra handles stored on a profile-handles event (deduped, ordered, capped). */
export function parseProfileHandles(event: { tags: string[][] }): string[] {
  const handles = event.tags
    .filter(([name, value]) => name === 'nip05' && !!value?.trim())
    .map(([, value]) => value.trim().toLowerCase())
    .filter((value) => NIP05_HANDLE_RE.test(value));
  return [...new Set(handles)].slice(0, MAX_PROFILE_HANDLES);
}

/** Tags for the addressable record. An empty list clears the extras (replace). */
export function profileHandlesTags(handles: string[]): string[][] {
  const clean = [
    ...new Set(handles.map((h) => h.trim().toLowerCase()).filter((h) => NIP05_HANDLE_RE.test(h))),
  ].slice(0, MAX_PROFILE_HANDLES);
  const tags: string[][] = [
    ['d', PROFILE_HANDLES_D],
    ['alt', 'SkateSpots profile handles'],
  ];
  for (const handle of clean) tags.push(['nip05', handle]);
  return tags;
}