export default function extendFenceLineNumbers(md: any, alt?: string): void {
  const fence = md.renderer.rules.fence
  md.renderer.rules.fence = (...args: any[]) => {
    const rawCode = fence(...args)
    const code = rawCode.slice(rawCode.indexOf('<code>') + 6, rawCode.indexOf('</code>'))

    const lines = code.trim().split('\n')

    const lineNumbersCode = [...Array(lines.length)]
      .map(
        (line, index) =>
          `<div class="q-markdown--line-number">${alt === void 0 ? index + 1 : alt}</div>`,
      )
      .join('')

    const lineNumbersWrapperCode = `<div class="q-markdown--line-numbers non-selectable">${lineNumbersCode}</div><div class="q-markdown--code-wrapper">${rawCode}</div>`

    const finalCode = `<div class="q-markdown--line-numbers-wrapper">${lines.length < 3 ? rawCode : lineNumbersWrapperCode}</div>`

    return finalCode
  }
}