import areaData from 'china-area-data';

export interface CascadeOption {
  value: string;
  label: string;
  children?: CascadeOption[];
}

/**
 * 将 china-area-data 原始数据转换为 antd Cascader 所需的 options 格式
 *
 * 原始数据格式: { '86': { '110000': '北京' }, '110000': { '110100': '市辖区' }, ... }
 * 目标格式: [{ value: '110000', label: '北京', children: [...] }]
 */
function buildTree(parentCode: string): CascadeOption[] {
  const nodes = areaData[parentCode];
  if (!nodes) return [];

  return Object.entries(nodes).map(([code, name]) => {
    const node: CascadeOption = {
      value: code,
      label: name as string,
    };
    const children = buildTree(code);
    if (children.length > 0) {
      node.children = children;
    }
    return node;
  });
}

/** 省市区三级联动数据 */
export const regionOptions: CascadeOption[] = buildTree('86');