Function resolveInternalNoteHref

packages/app-core/src/lib/internal-links.ts:81–107

(
  notePath: string | null | undefined,
  href: string,
  notes: NoteRef[]
)

 * Returns null for external links, in-page anchors, assets, or no match.
 */
export function resolveInternalNoteHref(
  notePath: string | null | undefined,
  href: string,
  notes: NoteRef[]
): InternalNoteLink | null {
  if (!notePath) return null
  const raw = href.trim()
  if (!raw || isExternalHref(raw)) return null

  const hashIdx = raw.indexOf('#')
  const rawPath = hashIdx >= 0 ? raw.slice(0, hashIdx) : raw
  if (!rawPath) return null // pure "#heading" — same note, handled elsewhere
  const heading = hashIdx >= 0 ? decode(raw.slice(hashIdx + 1)).trim() || null : null

  const decoded = decode(rawPath)
  const noteDir = notePath.includes('/') ? notePath.slice(0, notePath.lastIndexOf('/')) : ''
  let target = decoded.startsWith('/')
    ? decoded.replace(/^\/+/, '')
    : noteDir
      ? posixJoin(noteDir, decoded)
      : decoded
  target = posixNormalize(target)
  if (!target || target === '..' || target.startsWith('../')) return null

  const match = matchNote(notes, target)
  return match ? { path: match, heading } : null
}

function unwrapMdUrl(url: string): string {
  // Markdown wraps URLs containing spaces in angle brackets: `[x](<a b.pdf>)`.