Crude Built-in-five-minute tree generator (only two layers) (do not use, code is shit and could break!)

puumalligen.js

let main = ["vanilja", "mansikka", "sulkaa", "päärynä"];

let sub = ["sulkaa", "kinuski"];

let tree = {};

main.forEach(item => {
    tree[item] = sub;
})

let spacing = "  ";

let layers = ["", "", ""];

Object.keys(tree).forEach(key => {
    let items = tree[key];
    let length = spacing.length;
    //layers[2] = layers[2].substr(0, layers[1].length-1)
    items.forEach(item => {
        length+=item.length+spacing.length;
        layers[1] += " ".repeat(item.length+spacing.length-1)+"|"+" ".repeat(item.length+spacing.length-1)
        let calculated = (" ".repeat(((item.length+spacing.length)-(item.length/2))-1));
        let end = (" ".repeat((item.length+spacing.length)-(item.length/2)));
        layers[2] += end+item+calculated;
        layers[2] = layers[2].substr(0, layers[1].length-1)
        //layers[2] += " ";
    });
    layers[1] = layers[1].substr(0, layers[1].length-1)
    let distance = Math.abs(length-key.length);
    layers[0] += " ".repeat(distance)+key+" ".repeat(distance);
});

layers.forEach((item, index) => {
    if (index === 0 || index === layers.length-1)
        console.log("\n"+item);
    else {
        console.log(("\n"+item).repeat(3));
    }
})

console.log("\n".repeat(2));
console.log("Erilaisia yhdistelmiä saa muodosteltua: "+main.length+"x"+sub.length+"="+(main.length*sub.length));