${callouts[calloutType]}
                  ${title}
                  ${collapse ? toggleIcon : ""}
                
 `,
                }
                const blockquoteContent: (BlockContent | DefinitionContent)[] = [titleHtml]
                if (remainingText.length > 0) {
                  blockquoteContent.push({
                    type: "paragraph",
                    children: [
                      {
                        type: "text",
                        value: remainingText,
                      },
                    ],
                  })
                }
                // replace first line of blockquote with title and rest of the paragraph text
                node.children.splice(0, 1, ...blockquoteContent)
                // add properties to base blockquote
                node.data = {
                  hProperties: {
                    ...(node.data?.hProperties ?? {}),
                    className: `callout ${collapse ? "is-collapsible" : ""} ${
                      defaultState === "collapsed" ? "is-collapsed" : ""
                    }`,
                    "data-callout": calloutType,
                    "data-callout-fold": collapse,
                  },
                }
              }
            })
          }
        })
      }
      if (opts.mermaid) {
        plugins.push(() => {
          return (tree: Root, _file) => {
            visit(tree, "code", (node: Code) => {
              if (node.lang === "mermaid") {
                node.data = {
                  hProperties: {
                    className: ["mermaid"],
                  },
                }
              }
            })
          }
        })
      }
      return plugins
    },
    htmlPlugins() {
      const plugins: PluggableList = [rehypeRaw]
      if (opts.parseBlockReferences) {
        plugins.push(() => {
          const inlineTagTypes = new Set(["p", "li"])
          const blockTagTypes = new Set(["blockquote"])
          return (tree: HtmlRoot, file) => {
            file.data.blocks = {}
            visit(tree, "element", (node, index, parent) => {
              if (blockTagTypes.has(node.tagName)) {
                const nextChild = parent?.children.at(index! + 2) as Element
                if (nextChild && nextChild.tagName === "p") {
                  const text = nextChild.children.at(0) as Literal
                  if (text && text.value && text.type === "text") {
                    const matches = text.value.match(blockReferenceRegex)
                    if (matches && matches.length >= 1) {
                      parent!.children.splice(index! + 2, 1)
                      const block = matches[0].slice(1)
                      if (!Object.keys(file.data.blocks!).includes(block)) {
                        node.properties = {
                          ...node.properties,
                          id: block,
                        }
                        file.data.blocks![block] = node
                      }
                    }
                  }
                }
              } else if (inlineTagTypes.has(node.tagName)) {
                const last = node.children.at(-1) as Literal
                if (last && last.value && typeof last.value === "string") {
                  const matches = last.value.match(blockReferenceRegex)
                  if (matches && matches.length >= 1) {
                    last.value = last.value.slice(0, -matches[0].length)
                    const block = matches[0].slice(1)
                    if (!Object.keys(file.data.blocks!).includes(block)) {
                      node.properties = {
                        ...node.properties,
                        id: block,
                      }
                      file.data.blocks![block] = node
                    }
                  }
                }
              }
            })
            file.data.htmlAst = tree
          }
        })
      }
      if (opts.enableYouTubeEmbed) {
        plugins.push(() => {
          return (tree: HtmlRoot) => {
            visit(tree, "element", (node) => {
              if (node.tagName === "img" && typeof node.properties.src === "string") {
                const match = node.properties.src.match(ytLinkRegex)
                const videoId = match && match[2].length == 11 ? match[2] : null
                if (videoId) {
                  node.tagName = "iframe"
                  node.properties = {
                    class: "external-embed",
                    allow: "fullscreen",
                    frameborder: 0,
                    width: "600px",
                    height: "350px",
                    src: `https://www.youtube.com/embed/${videoId}`,
                  }
                }
              }
            })
          }
        })
      }
      return plugins
    },
    externalResources() {
      const js: JSResource[] = []
      if (opts.callouts) {
        js.push({
          script: calloutScript,
          loadTime: "afterDOMReady",
          contentType: "inline",
        })
      }
      if (opts.mermaid) {
        js.push({
          script: `
          import mermaid from 'https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.esm.min.mjs';
          const darkMode = document.documentElement.getAttribute('saved-theme') === 'dark'
          mermaid.initialize({
            startOnLoad: false,
            securityLevel: 'loose',
            theme: darkMode ? 'dark' : 'default'
          });
          document.addEventListener('nav', async () => {
            await mermaid.run({
              querySelector: '.mermaid'
            })
          });
          `,
          loadTime: "afterDOMReady",
          moduleType: "module",
          contentType: "inline",
        })
      }
      return { js }
    },
  }
}
declare module "vfile" {
  interface DataMap {
    blocks: Record