familytree.js

/*
 * Who are the { parents, children, grandchildren, grandparents, siblings, ... } of { name }?
 *
 * Let's start with just a small set:
 *    Amy and Bob have children Carol, Doug, Erin
 *    Carol and Xavier have children Mike, Nina
 *
 *       Amy + Bob  <- we only care about genetic relations, don't fuss about the "+" as something we need!
 *       /   |  \
 *   Doug  Erin  Carol + Xavier
 *     /              / \
 *   Ralphie       Mike Nina
 */


class Person{
    constructor(name, parents, siblings, children){
        this.name = name;
        this.parents = parents || [];
        this.siblings = siblings || [];
        this.children = children || [];
    }
    addParent(parent){
        this.parents.push(parent);
    }
    addSibling(sibling){
        if(this === sibling) {
            return;
        }
        if(this.siblings.indexOf(sibling) === -1) {
            this.siblings.push(sibling);
        }
        for(let s in this.siblings) {
            if(this.siblings[s].siblings.indexOf(this) === -1) {
                this.siblings[s].addSibling(this);
            }
        }
    }
    addChild(child){
        this.children.push(child);
        child.addParent(this);
        for(let c in this.children) {
            this.children[c].addSibling(child);
            child.addSibling(this.children[c])
        }
    }
    getGrandparents(names=false){
        const grandparents = [];
        for(let p in this.parents) {
            if(this.parents[p].parents) {
                grandparents.push(...this.parents[p].parents);
            }
        }
        return grandparents;
    }
    getGrandchildren(names=false){
        const grandchildren = [];
        for(let c in this.children) {
            if(this.children[c].children) {
                grandchildren.push(...this.children[c].children);
            }
        }
        return grandchildren;
    }
    getCousins(){
        const cousins = [];
        for(let p in this.parents) {
            for(let s in this.parents[p].siblings){
                cousins.push(...this.parents[p].siblings[s].children)
            }
        }
        return cousins;
    }
}

const Amy = new Person("Amy");
const Bob = new Person("Bob");
const Doug = new Person("Doug");
const Erin = new Person("Erin");
const Carol = new Person("Carol");
const Xavier = new Person("Xavier");
const Mike = new Person("Mike");
const Nina = new Person("Nina");
const Ralphie = new Person("Ralphie");

Amy.addChild(Doug)
Amy.addChild(Erin)
Amy.addChild(Carol)
Bob.addChild(Doug)
Bob.addChild(Erin)
Bob.addChild(Carol)
Carol.addChild(Mike)
Carol.addChild(Nina)
Xavier.addChild(Mike)
Xavier.addChild(Nina)
Doug.addChild(Ralphie)

console.log(Mike.getCousins().map((ar)=>{return ar.name}));
console.log(Nina.getCousins().map((ar)=>{return ar.name}));
console.log(Nina.getGrandparents().map((ar)=>{return ar.name}));
console.log(Ralphie.getCousins().map((ar)=>{return ar.name}));
console.log(Amy.getGrandchildren().map((ar)=>{return ar.name}));