import type { SlashMenuState } from '@admin/utils/editor/slash-menu-state'
import type { Editor } from '@tiptap/react'

const SLASH_QUERY_LIMIT = 48

export function getSlashMenuState(editor: Editor): SlashMenuState | null {
  const { selection } = editor.state

  if (!selection.empty || !editor.isEditable) return null

  const { $from } = selection
  const parent = $from.parent

  if (!parent.isTextblock || parent.type.name === 'codeBlock') return null

  const textBeforeCursor = parent.textBetween(0, $from.parentOffset, '\n', '\ufffc')
  const slashIndex = textBeforeCursor.lastIndexOf('/')

  if (slashIndex === -1) return null
  if (slashIndex > 0 && !/\s/.test(textBeforeCursor[slashIndex - 1])) {
    return null
  }

  const query = textBeforeCursor.slice(slashIndex + 1)

  if (query.includes('/') || query.length > SLASH_QUERY_LIMIT) return null

  const from = $from.start() + slashIndex
  const to = selection.from

  try {
    const coords = editor.view.coordsAtPos(from)
    return {
      from,
      to,
      query,
      rect: new DOMRect(
        coords.left,
        coords.top,
        Math.max(1, coords.right - coords.left),
        Math.max(1, coords.bottom - coords.top)
      )
    }
  } catch {
    return null
  }
}