const deckBase = (import.meta as ImportMeta & { env: { BASE_URL: string } }).env.BASE_URL

export function resolveImageSource(source: string | undefined, base = deckBase) {
  if (!source || isAbsoluteSource(source))
    return source

  const normalizedBase = base.endsWith('/') ? base : `${base}/`
  return `${normalizedBase}${source.replace(/^\.\//, '')}`
}

function isAbsoluteSource(source: string) {
  return source.startsWith('/')
    || source.startsWith('#')
    || /^[a-z][a-z\d+.-]*:/i.test(source)
}