contentlayer.config.js

import rehypeAutolinkHeadings from 'rehype-autolink-headings'
import rehypePrettyCode from 'rehype-pretty-code'
import rehypeSlug from 'rehype-slug'
import remarkGfm from 'remark-gfm'
import { rehypePrettyCodeOptions } from './lib/rehypePrettyCode'
import { codeImport } from 'remark-code-import'
import { visit } from 'unist-util-visit'

import { defineDocumentType, makeSource } from 'contentlayer/source-files'

/** @type {import('contentlayer/source-files').ComputedFields} */
const computedFields = {
  slug: {
    type: 'string',
    resolve: (doc) => `/${doc._raw.flattenedPath.toLowerCase()}`,
  },
  slugAsParams: {
    type: 'string',
    resolve: (doc) => doc._raw.flattenedPath.split('/')[0].toLowerCase(),
  },
}

export const Blog = defineDocumentType(() => ({
  name: 'Blog',
  filePathPattern: `**/*.mdx`,
  contentType: 'mdx',
  fields: {
    title: {
      type: 'string',
      required: true,
    },
    publishedAt: {
      type: 'string',
      default: true,
    },
    description: {
      type: 'string',
      default: '',
      required: true,
    },
    author: {
      type: 'string',
      required: true,
    },
    keyWords: {
      type: 'string',
      required: true,
    },
    blog_count: {
      type: 'string',
      required: true,
    },
  },
  computedFields,
}))

export default makeSource({
  contentDirPath: 'content',
  documentTypes: [Blog],
  mdx: {
    remarkPlugins: [remarkGfm, codeImport],
    rehypePlugins: [
      rehypeSlug,
      () => (tree) => {
        visit(tree, (node) => {
          if (node?.type === 'element' && node?.tagName === 'pre') {
            const [codeEl] = node.children
            if (codeEl.tagName !== 'code') {
              return
            }

            if (codeEl.data?.meta) {
              // Extract event from meta and pass it down the tree.
              const regex = /event="([^"]*)"/
              const match = codeEl.data?.meta.match(regex)
              if (match) {
                node.__event__ = match ? match[1] : null
                codeEl.data.meta = codeEl.data.meta.replace(regex, '')
              }
            }

            node.__rawString__ = codeEl.children?.[0].value
            node.__src__ = node.properties?.__src__
            node.__style__ = node.properties?.__style__
          }
        })
      },
      rehypePrettyCode,
      rehypePrettyCodeOptions,
      () => (tree) => {
        visit(tree, (node) => {
          if (node?.type === 'element' && node?.tagName === 'div') {
            if (!('data-rehype-pretty-code-fragment' in node.properties)) {
              return
            }

            const preElement = node.children.at(-1)
            if (preElement.tagName !== 'pre') {
              return
            }

            preElement.properties['__withMeta__'] =
              node.children.at(0).tagName === 'div'
            preElement.properties['__rawString__'] = node.__rawString__

            if (node.__src__) {
              preElement.properties['__src__'] = node.__src__
            }

            if (node.__event__) {
              preElement.properties['__event__'] = node.__event__
            }

            if (node.__style__) {
              preElement.properties['__style__'] = node.__style__
            }
          }
        })
      },
      [
        rehypeAutolinkHeadings,
        {
          properties: {
            className: ['subheading-anchor'],
            ariaLabel: 'Link to section',
          },
        },
      ],
    ],
  },
})