/**
 * 功能：为资源表单和详情页加载、缓存并搜索关联资源选项。
 * 版本：v1.0.0
 */
import { Message } from '@arco-design/web-vue';
import { reactive } from 'vue';
import { resourceApi } from '@/api/resource';
import type { ResourceField } from '@/api/resources';
import type { ResourceRow } from '@/api/resource-page-rules';

export function useResourceRelations() {
  const options = reactive<Record<string, ResourceRow[]>>({});
  const loading = reactive<Record<string, boolean>>({});
  const timers = new Map<string, ReturnType<typeof setTimeout>>();

  /** 加载一类关联资源，工作人员关系默认只选择配送人员。 */
  async function load(resource: string, keyword = '') {
    loading[resource] = true;
    try {
      const filters: Record<string, string> = keyword ? { keyword } : {};
      if (resource === '/staff_account') filters.role_code = 'delivery';
      options[resource] = (
        await resourceApi.list<ResourceRow>(resource, 1, 100, filters)
      ).list;
    } catch (error) {
      Message.error(`关联数据加载失败：${(error as Error).message}`);
    } finally {
      loading[resource] = false;
    }
  }

  /** 预加载当前页面实际使用的全部关系字段。 */
  async function preload(fields: ResourceField[]) {
    const resources = new Set(
      fields
        .map((field) => field.relation)
        .filter((value): value is string => Boolean(value)),
    );
    await Promise.all([...resources].map((resource) => load(resource)));
  }

  /** 对远程关系选项进行防抖搜索。 */
  function search(resource: string | undefined, keyword: string) {
    if (!resource) return;
    const timer = timers.get(resource);
    if (timer) clearTimeout(timer);
    timers.set(
      resource,
      setTimeout(() => load(resource, keyword.trim()), 250),
    );
  }

  return { options, loading, load, preload, search };
}