import * as nodeHtmlParser from 'node-html-parser'
import Turndown from 'turndown'

// @ts-ignore
import * as turndownPluginGfm from 'turndown-plugin-gfm'
import { PageMetadata } from '../../shared/lib/PagesMetadata'
import { TransformerConfig } from '../types/config.types'

const turndown = new Turndown({
  headingStyle: 'atx',
  fence: '```',
  emDelimiter: '_',
  strongDelimiter: '**',
  linkStyle: 'inlined',
  linkReferenceStyle: 'full',
  codeBlockStyle: 'fenced',
  bulletListMarker: '-',
})

turndown.use([turndownPluginGfm.tables, turndownPluginGfm.strikethrough])

const removeElement = (
  node: nodeHtmlParser.HTMLElement,
  ...selectors: string[]
) => {
  for (const selector of selectors) {
    const elements = node.querySelectorAll(selector)

    elements.forEach((el) => el.remove())
  }
}

export const parsePageHtmlContent = async (
  html: string,
  pageMetadata: PageMetadata,
  config: TransformerConfig,
) => {
  const parsed = nodeHtmlParser.parse(html, {
    blockTextElements: {
      script: false,
      style: false,
    },
  })
  // const head = parsed.querySelector('head')

  const article = parsed.querySelector('body article')

  if (!article) {
    return null
  }

  removeElement(article, '.nextra-breadcrumb', 'svg', 'img')

  article.querySelectorAll('h1, h2, h3, h4, h5, h6').forEach((el) => {
    removeElement(el, 'a')
  })

  article.querySelectorAll('a').forEach((el) => {
    el.innerHTML = el.textContent.replaceAll('\n', ' ')
  })

  const metadata: Record<string, any> = pageMetadata.frontMatter || {}
  metadata.title = pageMetadata.title
  metadata.__path__ = JSON.stringify(pageMetadata.path)

  if (metadata.keywords) {
    metadata.keywords = metadata.keywords
      .split(',')
      .map((keyword: string) => keyword.trim())
  }

  return {
    metadata,
    html: article.outerHTML,
  }
}