问创建层次结构-JavaScript的树结构

EN

const staffMembers = [
    { 
        "_id" :0, 
        "name" : "David", 
        "surname" : "Smith", 
        "slug": "david-smith",
        "category" : "operations",
        "title": "Head of Development",
        "reportsTo": "bruce-davids"
    },
    { 
        "_id" :1, 
        "name" : "John", 
        "surname" : "Jones", 
        "slug": "john-jones",
        "category" : "operations",
        "title": "Head of Marketing",
        "reportsTo": "bruce-davids"
    },
    { 
        "_id" :3, 
        "name" : "Nick", 
        "surname" : "Thompson", 
        "slug": "nick-thompson",
        "category" : "operations",
        "title": "Head of Design",
        "reportsTo": "terry-cats"
    },
    { 
        "_id" :4, 
        "name" : "Nick", 
        "surname" : "Jenson", 
        "slug": "nick-jenson",
        "category" : "interns",
        "title": "Intern designer",
        "reportsTo": "nick-thompson" 
    },
    { 
        "_id" :6, 
        "name" : "Terry", 
        "surname" : "Cats", 
        "slug": "terry-cats",
        "category" : "c-suite",
        "title": "Chief Creative Officer",
        "reportsTo": "" 
    },
    { 
        "_id" :7, 
        "name" : "Bruce", 
        "surname" : "Davids", 
        "slug": "bruce-davids",
        "category" : "c-suite",
        "title": "Chief Strategy Officer",
        "reportsTo": "" 
    },
    { 
        "_id" :8, 
        "name" : "Bill", 
        "surname" : "Bass", 
        "slug": "bill-bass",
        "category" : "c-suite",
        "title": "Chief Executive Officer",
        "reportsTo": "" 
    }
]

const categories = [
    { 
        "_id" :0, 
        "name" : "Executive", 
        "parent" : "", 
        "slug" : "c-suite" 
    },
    { 
        "_id" :1, 
        "name" : "Operations", 
        "parent" : "c-suite", 
        "slug" : "operations" 
    },
    { 
        "_id" :2, 
        "name" : "Interns", 
        "parent" : "operations", 
        "slug" : "interns" 
    },
];

const hierarchy = (data) => {
    const tree = [];
    const childOf = {};
    let results = [];
        let cat = "";
        let childrens = [];
    data.forEach((item,index) => {
        const { slug, reportsTo, category } = item;
        // console.log(category);
        childOf[slug] = childOf[slug] || [];
        item.children = childOf[slug];
        reportsTo ? (childOf[reportsTo] = childOf[reportsTo] || []).push(item) : tree.push(item);
        // if(category == categories.slug ){
            cat = category;
            const indexs = categories.findIndex(object => {
                return object._id;
            });
        // }
        });
  
  for(let i = 0;i < tree.length;i++){
    for(let j = 0;j < tree[i].children.length;j++){

        childrens = (tree[i].children[j]);
    }
    results.push(tree[i].name + " " + tree[i].surname + " - " + tree[i].title +": " 
    + cat + '*' + childrens.name + " " + childrens.surname + " - " + childrens.title + ": " + "cat"+cat);
  }
    return results;

};