Code

editor.tsx

import 'prosekit/basic/style.css'

import { createEditor, jsonFromNode, type NodeJSON } from 'prosekit/core'
import type { ProseMirrorNode } from 'prosekit/pm/model'
import { ProseKit, useDocChange } from 'prosekit/react'
import { useCallback, useMemo } from 'react'

import { defineExtension } from './extension'

export default function Editor({
  defaultContent,
  onDocUpdate,
}: {
  defaultContent?: NodeJSON
  onDocUpdate?: (doc: NodeJSON) => void
}) {
  const editor = useMemo(() => {
    const extension = defineExtension()
    return createEditor({ extension, defaultContent })
  }, [defaultContent])

  const handleDocChange = useCallback(
    (doc: ProseMirrorNode) => onDocUpdate?.(jsonFromNode(doc)),
    [onDocUpdate],
  )
  useDocChange(handleDocChange, { editor })

  return (
    <ProseKit editor={editor}>
      <div className='box-border h-full w-full min-h-36 overflow-y-hidden overflow-x-hidden rounded-md border border-solid border-gray-200 shadow dark:border-zinc-700 flex flex-col bg-white dark:bg-neutral-900'>
        <div className='relative w-full flex-1 box-border overflow-y-scroll'>
          <div ref={editor.mount} className='ProseMirror box-border min-h-full px-[max(4rem,_calc(50%-20rem))] py-8 outline-none outline-0 [&_span[data-mention="user"]]:text-blue-500 [&_span[data-mention="tag"]]:text-violet-500 [&_pre]:text-white [&_pre]:bg-zinc-800'></div>
        </div>
      </div>
    </ProseKit>
  )
}

extension.ts

import { defineBasicExtension } from 'prosekit/basic'
import { union } from 'prosekit/core'
import { definePlaceholder } from 'prosekit/extensions/placeholder'

export function defineExtension() {
  return union(
    defineBasicExtension(),
    definePlaceholder({ placeholder: 'Type something...' }),
  )
}

export type EditorExtension = ReturnType<typeof defineExtension>