How to group by and sum an array of objects javascript?

const array = [
  {
      "data": {
          "qty": "5",
          "toy": {
              "id": 3,
          },
          "available": "yes",
      }
  },
  {
      "data": {
          "qty": "5",
          "toy": {
              "id": 10,
          },
          "available": "no"
      }
  },
  {
      "data": {
          "qty": "59",
          "toy": {
              "id": 10,
          },
          "available": "yes",
      }
  },
  {
      "data": {
          "qty": "5",
          "toy": {
              "id": 3,
          },
          "available": "yes",
      }
  }
]


var result = [];
array.reduce(function(res, value) {
  if (!res['data']['toy'] || !res['data']['toy']['data']) {
    res['data'] = {...value['data'] };
    result.push(res['data'])
  }
  if (res['data']['available'] === value['data']['available'] && res['data']['toy']['id'] === value['data']['toy']['id']) {
    res['data']['qty'] = parseInt(res['data']['qty']) + parseInt(value['data'].qty)
  }
  return res;
}, {'data': {}});

console.log(result)

I am working on a js project and I need a bit of help here. From the array, How to get a new array that has qty as the sum of the other qty value which data.toy.id and available same. i.e. I want the below array. My code is not working as excepted. Changes to the same or new code are also fine. Thank you.

const array = [
  {
      "data": {
          "qty": "10",
          "toy": {
              "id": 3,
          },
          "available": "yes",
      }
  },
  {
      "data": {
          "qty": "5",
          "toy": {
              "id": 10,
          },
          "available": "no"
      }
  },
  {
      "data": {
          "qty": "59",
          "toy": {
              "id": 10,
          },
          "available": "yes",
      }
  }
]

>Solution :

You group the array into an object, where the keys are concatenation of available and id properties and finally transform the object back to an array using Object.values.

const 
  array = [
    { data: { qty: "5", toy: { id: 3 }, available: "yes" } },
    { data: { qty: "5", toy: { id: 10 }, available: "no" } },
    { data: { qty: "59", toy: { id: 10 }, available: "yes" } },
    { data: { qty: "5", toy: { id: 3 }, available: "yes" } },
  ],
  result = Object.values(
    array.reduce((r, { data }) => {
      const k = data.available + data.toy.id;
      if (r[k]) {
        r[k].data.qty = String(Number(r[k].data.qty) + Number(data.qty));
      } else {
        r[k] = { data };
      }
      return r;
    }, {})
  );

console.log(result);