Subset-Sum Solution in javascript

subsetsum.js

var subset_sum = function(items, target) {
    var perms = [], layer = 0, depth = 4, attempts = 0, sum, perm,
    ss = function(items) {
        var item = items.shift();
        for (i = 0; i < items.length; i++) {
            attempts = attempts + 1;
            if (attempts <= items.length * items.length) {
                if (layer === 0) {
                    perm = [items[0], items[i]];
                } else {
                    perm = perms.shift();
                    perm.push(items[0]);
                }
                sum = 0;
                for(j = 0;j < perm.length; j++){
                    sum += perm[j];
                }
                perms.push(perm);
                if (sum == target){
                    return perm;
                }
            } else {
                if (layer < depth) {
                    attempts = 0;
                    layer = layer + 1;
                } else {
                    return null;
                }
            }
        }
        items.push(item);
        return ss(items);
    }
    return ss(items)
}

items = [1, 2, 3, 4, 5];

target = 15;

result = subset_sum(items, target);

console.log(result);

subset_sum([1, 2], 3) // returns null

need to optimize it brooo, dunno how 😞