@sveltek/unplugins/dist/index.mjs

Sveltek's Unified plugins for Markdown preprocessor.

import { visit } from 'unist-util-visit';

const remarkToc = (options = {}) => {
  const { depth = 3, links = true } = options;
  return (tree, vfile) => {
    const frontmatter = vfile.data.frontmatter;
    const toc = [];
    let i = 0;
    visit(tree, "heading", (node) => {
      const [child] = node.children;
      let value = "";
      let id = "";
      if (child.type === "text") {
        value = child.value;
        id = value.toLowerCase().replace(/[^a-z0-9\s-]/g, "").trim().replace(/\s+/g, "-");
      }
      if (links) {
        node.children = [];
        node.children.push({
          type: "link",
          url: `#${id}`,
          children: [{ type: "text", value }]
        });
      }
      const data = node.data || (node.data = {});
      const props = data.hProperties || (data.hProperties = {});
      if (node.depth > 1 && node.depth <= depth) {
        if (toc.some((h) => h.id === id)) id = `${id}-${i + 1}`;
        if (!props.id) props.id = id;
        toc.push({ id, depth: node.depth, value });
      }
    });
    frontmatter.toc = toc;
  };
};

const countWords = (text) => (text.match(/\S+/g) || []).length;
const readingStats = (text, { wordsPerMinute = 200 } = {}) => {
  const words = countWords(text);
  const min = words / wordsPerMinute;
  const minutes = min < 1 ? 1 : Math.round(min * 10) / 10;
  return { minutes, words, text: `${minutes} min read` };
};

const remarkReadingStats = (options = {}) => {
  const { wordsPerMinute } = options;
  return (tree, vfile) => {
    const frontmatter = vfile.data.frontmatter;
    let text = "";
    visit(tree, "text", (node) => {
      text += node.value;
    });
    frontmatter.readingStats = readingStats(text, { wordsPerMinute });
  };
};

const isFunction = (v) => v instanceof Function;

const rehypeShiki = function(options = {}) {
  const {
    theme,
    themes,
    langs,
    highlighter,
    codeToHtml: codeHtmlOptions,
    root = (node) => {
      node.tagName = "div";
    }
  } = options;
  const defaultTheme = theme || "github-dark-default";
  const defaultLangs = langs || ["javascript", "typescript", "svelte"];
  return async (tree, file) => {
    const { rehypeHighlight } = await import('@sveltek/markdown');
    const { getSingletonHighlighter } = await import('shiki');
    const shikiHighlighter = getSingletonHighlighter({
      ...highlighter,
      themes: highlighter?.themes || themes && Object.values(themes) || [defaultTheme],
      langs: highlighter?.langs || defaultLangs
    });
    const { codeToHtml } = await shikiHighlighter;
    const highlightOptions = {
      highlighter: async ({ code, lang, meta }) => {
        const parsedMeta = options.parseMeta?.(meta);
        if (parsedMeta) meta = parsedMeta;
        const codeHtml = isFunction(codeHtmlOptions) ? codeHtmlOptions({ code, lang, meta }) : codeHtmlOptions;
        if (code) {
          return codeToHtml(code, {
            ...codeHtml,
            lang: lang || "text",
            ...themes ? { themes: codeHtml?.themes || themes } : { theme: codeHtml?.theme || defaultTheme }
          });
        }
      },
      root
    };
    const transformer = rehypeHighlight.call(this, highlightOptions);
    return transformer?.(tree, file, () => {
    });
  };
};

export { rehypeShiki, remarkReadingStats, remarkToc };