import { defineStore } from 'pinia'
import { getOrganizationTreeApi, type OrganizationNode } from '@/api/organization'
import { useUserStore } from '@/stores/user'

const CACHE_MAX_AGE = 24 * 60 * 60 * 1000
const CACHE_SCHEMA_VERSION = 1

let requestPromise: Promise<OrganizationNode[]> | null = null

/**
 * 机构树共享缓存。
 *
 * 只持久化精简后的 code/name/children，并按登录账号隔离，
 * 避免不同账号共用可能存在权限差异的机构数据。
 */
export const useOrganizationStore = defineStore(
  'organization',
  () => {
    const tree = ref<OrganizationNode[]>([])
    const cachedAt = ref(0)
    const cacheOwner = ref('')
    const schemaVersion = ref(CACHE_SCHEMA_VERSION)
    const loading = ref(false)

    const hasCache = computed(() => tree.value.length > 0)
    const organizationNameMap = computed(() => {
      const nameMap = new Map<string, string>()
      const nodes = [...tree.value]

      while (nodes.length) {
        const node = nodes.pop()
        if (!node) continue

        nameMap.set(node.code, node.name)
        if (node.children?.length) nodes.push(...node.children)
      }

      return nameMap
    })

    /** 根据机构号从缓存的机构树中获取机构名称。 */
    function getOrganizationName(code?: string) {
      const organizationCode = code?.trim()
      return organizationCode ? organizationNameMap.value.get(organizationCode) || '' : ''
    }

    async function ensureOrganizationTree(force = false) {
      const owner = useUserStore().username.trim()

      if (cacheOwner.value !== owner || schemaVersion.value !== CACHE_SCHEMA_VERSION) {
        clearOrganizationCache()
      }

      const cacheFresh = Date.now() - cachedAt.value < CACHE_MAX_AGE
      if (!force && hasCache.value && cacheFresh) return tree.value
      if (requestPromise) return requestPromise

      loading.value = true
      requestPromise = getOrganizationTreeApi()
        .then((result) => {
          if (!result.length) throw new Error('机构树数据为空')

          tree.value = result
          cachedAt.value = Date.now()
          cacheOwner.value = owner
          schemaVersion.value = CACHE_SCHEMA_VERSION
          return tree.value
        })
        .catch((error) => {
          // 过期缓存仍可作为断网降级数据，首次加载失败则交给页面展示重试。
          if (hasCache.value) return tree.value
          throw error
        })
        .finally(() => {
          loading.value = false
          requestPromise = null
        })

      return requestPromise
    }

    function refreshOrganizationTree() {
      return ensureOrganizationTree(true)
    }

    function clearOrganizationCache() {
      tree.value = []
      cachedAt.value = 0
      cacheOwner.value = ''
      schemaVersion.value = CACHE_SCHEMA_VERSION
    }

    return {
      tree,
      cachedAt,
      cacheOwner,
      schemaVersion,
      loading,
      hasCache,
      getOrganizationName,
      ensureOrganizationTree,
      refreshOrganizationTree,
      clearOrganizationCache,
    }
  },
  {
    persist: {
      key: 'mini2_organization_cache',
      pick: ['tree', 'cachedAt', 'cacheOwner', 'schemaVersion'],
    },
  },
)