interface SeoEventQualityCandidate {
  slug?: string | null
  title?: string | null
  shortDescription?: string | null
  description?: string | null
}

const PLACEHOLDER_SLUG_PATTERNS = [/^generated-[a-z0-9]+$/i, /(?:^|-)copy(?:-|$)/i, /^bag+$/i, /^event-[0-9a-f]{8}$/i]

const PLACEHOLDER_TEXT_PATTERNS = [/^رویداد جدید\s*\d+$/u, /seed factory/i]

/** Excludes obvious seed/clone placeholders from public SEO discovery surfaces. */
export function isSeoEligibleEvent(event: SeoEventQualityCandidate): boolean {
  const slug = event.slug?.trim() ?? ''
  const text = [event.title, event.shortDescription, event.description].filter(Boolean).join(' ')

  if (!slug) return false
  if (PLACEHOLDER_SLUG_PATTERNS.some((pattern) => pattern.test(slug))) return false
  if (PLACEHOLDER_TEXT_PATTERNS.some((pattern) => pattern.test(text))) return false

  return true
}