import { fetchUserList } from '@/api/admin'

/** 生产任务步骤负责人须具备的角色（与 sys_role.role_name 精确匹配） */
export const PRODUCTION_STEP_ASSIGNEE_ROLE = '实验专员'

export function productionStepAssigneeUserListParams(query?: string) {
  return {
    page: 1,
    pageSize: 50,
    keyword: query?.trim() || undefined,
    status: '1',
    roleName: PRODUCTION_STEP_ASSIGNEE_ROLE
  }
}

let cachedDefaultUsers: Api.User.UserItem[] | null = null
const cacheByKeyword = new Map<string, Api.User.UserItem[]>()
let inflightDefault: Promise<Api.User.UserItem[]> | null = null
const inflightByKeyword = new Map<string, Promise<Api.User.UserItem[]>>()

/** 带会话内缓存的实验专员用户列表（派发/编辑步骤负责人下拉共用） */
export async function fetchProductionStepAssigneeUsers(query?: string) {
  const kw = (query || '').trim()

  if (!kw) {
    if (cachedDefaultUsers) {
      return { list: cachedDefaultUsers, total: cachedDefaultUsers.length }
    }
    if (!inflightDefault) {
      inflightDefault = fetchUserList(productionStepAssigneeUserListParams(''))
        .then((res) => {
          cachedDefaultUsers = res.list || []
          return cachedDefaultUsers
        })
        .finally(() => {
          inflightDefault = null
        })
    }
    const list = await inflightDefault
    return { list, total: list.length }
  }

  if (cacheByKeyword.has(kw)) {
    const list = cacheByKeyword.get(kw)!
    return { list, total: list.length }
  }

  let inflight = inflightByKeyword.get(kw)
  if (!inflight) {
    inflight = fetchUserList(productionStepAssigneeUserListParams(kw))
      .then((res) => {
        const list = res.list || []
        cacheByKeyword.set(kw, list)
        return list
      })
      .finally(() => {
        inflightByKeyword.delete(kw)
      })
    inflightByKeyword.set(kw, inflight)
  }
  const list = await inflight
  return { list, total: list.length }
}

export function invalidateProductionStepAssigneeUserCache() {
  cachedDefaultUsers = null
  cacheByKeyword.clear()
}