import { isMarkdownLineStart } from '@admin/utils/editor/is-markdown-line-start'

export function matchMarkdownBlockPrefix(markdown: string, index: number): number | null {
  if (!isMarkdownLineStart(markdown, index)) return null

  const match = /^(?: {0,3}(?:#{1,6}\s+|>\s?|[-*+]\s+\[[ xX]\]\s+|[-*+]\s+|\d+[.)]\s+))/.exec(
    markdown.slice(index)
  )

  return match ? index + match[0].length : null
}