dify/web/app/components/base/prompt-editor/plugins/history-block/index.tsx

import type { FC } from 'react'
import { useEffect } from 'react'
import {
  $insertNodes,
  COMMAND_PRIORITY_EDITOR,
  createCommand,
} from 'lexical'
import { mergeRegister } from '@lexical/utils'
import { useLexicalComposerContext } from '@lexical/react/LexicalComposerContext'
import {
  $createHistoryBlockNode,
  HistoryBlockNode,
} from './node'

export const INSERT_HISTORY_BLOCK_COMMAND = createCommand('INSERT_HISTORY_BLOCK_COMMAND')
export const DELETE_HISTORY_BLOCK_COMMAND = createCommand('DELETE_HISTORY_BLOCK_COMMAND')

export type RoleName = {
  user: string
  assistant: string
}

export type HistoryBlockProps = {
  roleName: RoleName
  onEditRole: () => void
  onInsert?: () => void
  onDelete?: () => void
}

const HistoryBlock: FC<HistoryBlockProps> = ({
  roleName,
  onEditRole,
  onInsert,
  onDelete,
}) => {
  const [editor] = useLexicalComposerContext()

  useEffect(() => {
    if (!editor.hasNodes([HistoryBlockNode]))
      throw new Error('HistoryBlockPlugin: HistoryBlock not registered on editor')

    return mergeRegister(
      editor.registerCommand(
        INSERT_HISTORY_BLOCK_COMMAND,
        () => {
          const historyBlockNode = $createHistoryBlockNode(roleName, onEditRole)

          $insertNodes([historyBlockNode])

          if (onInsert)
            onInsert()

          return true
        },
        COMMAND_PRIORITY_EDITOR,
      ),
      editor.registerCommand(
        DELETE_HISTORY_BLOCK_COMMAND,
        () => {
          if (onDelete)
            onDelete()

          return true
        },
        COMMAND_PRIORITY_EDITOR,
      ),
    )
  }, [editor, roleName, onEditRole, onInsert, onDelete])

  return null
}

export default HistoryBlock