树结构中查找最高父节点（顶层leader）的算法实现问题

输入任意人员的_id值，无论该人员是leader还是子节点，都需要返回对应的顶层leader的id。
示例：输入Rahman的id "615e8215c3055d1addc216b0" 或者Aaron Aziz的id "61164b4bc08f86505e7dcdd8"，都应该返回Aaron Aziz的id（他是该树的顶层leader）。

数据结构说明 #

数据本质为两层结构，每个顶层条目存储其直接子节点的引用，部分子节点可作为顶层条目的leader，以此构建更深层级的关联，完整数据如下：

"families": [
    {
        "datecreated": "2021-10-06T07:39:28.988Z",
        "_id": "615d52cb7cc6d32978afa694",
        "leader": {
            "_id": "61164b4bc08f86505e7dcdd8",
            "name": "Aaron Aziz"
        },
        "children": [
            {
                "datejoined": "2021-10-06T07:39:28.988Z",
                "_id": "615d52cb7cc6d32978afa695",
                "child": {
                    "_id": "615c15c66dd91a2d4385ac84",
                    "name": "Amirul Adha"
                }
            },
            {
                "datejoined": "2021-10-06T08:04:52.122Z",
                "_id": "615d58cf0f045f320cb28706",
                "child": {
                    "_id": "615d58b40f045f320cb28701",
                    "name": "Samirul Ali"
                }
            }
        ]
    },
    {
        "datecreated": "2021-10-07T05:12:22.671Z",
        "_id": "615e8475c3055d1addc216b5",
        "leader": {
            "_id": "615c15c66dd91a2d4385ac84",
            "name": "Amirul Adha"
        },
        "children": [
            {
                "datejoined": "2021-10-07T05:12:22.671Z",
                "_id": "615e8475c3055d1addc216b6",
                "child": {
                    "_id": "615e8215c3055d1addc216b0",
                    "name": "Rahman"
                }
            }
        ]
    },
    {
        "datecreated": "2021-10-07T08:52:47.840Z",
        "_id": "615eb630e0cc0d22281bb282",
        "leader": {
            "_id": "615e8215c3055d1addc216b0",
            "name": "Rahman"
        },
        "children": [
            {
                "datejoined": "2021-10-07T08:52:47.840Z",
                "_id": "615eb630e0cc0d22281bb283",
                "child": {
                    "_id": "615eb60de0cc0d22281bb27d",
                    "name": "Aizi"
                }
            }
        ]
    }
]

1. 递归调用的返回值没有被接收，向上查询父leader的结果直接丢失
2. 逻辑顺序错误：未确认当前id属于该family的子节点就直接赋值leader，且匹配失败时直接返回当前遍历的family的leader，逻辑完全不符合需求
3. 没有处理输入id本身就是顶层leader的场景

const findLeader = (currentId) => {
  // 遍历所有family，找currentId是不是某个family的子节点
  for (const family of familiesCopy) {
    const isChild = family.children.find(item => item.child._id === currentId);
    if (isChild) {
      // 找到父family，递归查询父leader的顶层id并直接返回
      return findLeader(family.leader._id);
    }
  }
  // 遍历完所有family都没找到父family，说明当前id就是顶层leader
  return currentId;
}

// 输入Aizi的id，返回Aaron Aziz的id：61164b4bc08f86505e7dcdd8
console.log(findLeader("615eb60de0cc0d22281bb27d")) 
// 输入Rahman的id，返回Aaron Aziz的id：61164b4bc08f86505e7dcdd8
console.log(findLeader("615e8215c3055d1addc216b0")) 
// 输入Aaron Aziz的id，返回自己的id
console.log(findLeader("61164b4bc08f86505e7dcdd8"))

内容的提问来源于stack exchange，提问作者Faris Malik