import { CONTENT_EDITOR_HIGHLIGHT_COLOR_NAME_PATTERN } from '@admin/utils/editor/content-editor-highlight-color-name-pattern'

const HIGHLIGHT_SPAN_OPEN_PATTERN = new RegExp(
  `^<span\\s+data-highlight-color="(?:${CONTENT_EDITOR_HIGHLIGHT_COLOR_NAME_PATTERN})">`,
  'i'
)

export function matchHtmlMarkSyntax(markdown: string, index: number): number | null {
  const remaining = markdown.slice(index)
  const match =
    /^<\/?(?:u|sub|sup|kbd)>/i.exec(remaining) ??
    HIGHLIGHT_SPAN_OPEN_PATTERN.exec(remaining) ??
    /^<\/span>/i.exec(remaining)

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