web/src/hooks/useD2Session.ts

import { useEffect, useState } from 'react'
import { getD2Account, getD2Csrf, onD2Change, type D2Account } from '../api/identity'

interface D2SessionState {
  account: D2Account | null
  csrf: string | null
  authed: boolean
  isOperator: boolean
}

function snapshot(): D2SessionState {
  const account = getD2Account()
  return {
    account,
    csrf: getD2Csrf(),
    authed: account !== null,
    isOperator: account?.role === 'operator',
  }
}

/** Subscribes to the in-memory D2 account/csrf store (api/identity.ts). */
export function useD2Session(): D2SessionState {
  const [state, setState] = useState<D2SessionState>(snapshot)
  useEffect(() => onD2Change(() => setState(snapshot())), [])
  return state
}