interface TreeHelperConfig {
  id: string;
  children: string;
  pid: string;
}
const DEFAULT_CONFIG: TreeHelperConfig = {
  id: 'id',
  children: 'children',
  pid: 'pid'
};
export const defaultProps = {
  children: 'children',
  label: 'name',
  value: 'id'
};

const getConfig = (config: Partial<TreeHelperConfig>) => Object.assign({}, DEFAULT_CONFIG, config);


/**
 * 构造树型结构数据
 * @param {*} data 数据源
 * @param {*} id id字段 默认 'id'
 * @param {*} parentId 父节点字段 默认 'parentId'
 * @param {*} children 孩子节点字段 默认 'children'
 */
export function handleTree(data: any[], id?: string, parentId?: string, children?: string) {
  if (!Array.isArray(data)) {
    console.warn('data must be an array');
    return [];
  }
  const config = {
    id: id || 'id',
    parentId: parentId || 'parentId',
    childrenList: children || 'children'
  };

  const childrenListMap = {};
  const nodeIds = {};
  const tree: any[] = [];

  for (const d of data) {
    const parentId = d[config.parentId];
    if (childrenListMap[parentId] == null) childrenListMap[parentId] = [];

    nodeIds[d[config.id]] = d;
    childrenListMap[parentId].push(d);
  }

  for (const d of data) {
    const parentId = d[config.parentId];
    if (nodeIds[parentId] == null) tree.push(d);
  }

  for (const t of tree) adaptToChildrenList(t);

  function adaptToChildrenList(o) {
    if (childrenListMap[o[config.id]] !== null) o[config.childrenList] = childrenListMap[o[config.id]];

    if (o[config.childrenList]) {
      for (const c of o[config.childrenList]) adaptToChildrenList(c);
    }
  }
  return tree;
}

/**
 * 构造树型结构数据
 * @param {*} data 数据源
 * @param {*} id id字段 默认 'id'
 * @param {*} parentId 父节点字段 默认 'parentId'
 * @param {*} children 孩子节点字段 默认 'children'
 * @param {*} rootId 根Id 默认 0
 */
export function handleTree2(data, id, parentId, children, rootId) {
  id = id || 'id';
  parentId = parentId || 'parentId';
  children = children || 'children';
  rootId =
    rootId ||
    Math.min(
      ...data.map((item) => {
        return item[parentId];
      })
    ) ||
    0;
  // 对源数据深度克隆
  const cloneData = JSON.parse(JSON.stringify(data));
  // 循环所有项
  const treeData = cloneData.filter((father) => {
    const branchArr = cloneData.filter((child) => {
      // 返回每一项的子级数组
      return father[id] === child[parentId];
    });
    // eslint-disable-next-line no-unused-expressions
    branchArr.length > 0 ? (father.children = branchArr) : '';
    // 返回第一层
    return father[parentId] === rootId;
  });
  return treeData !== '' ? treeData : data;
}