Alter array of object using map in javascript-CodePudding

I have an array of object: Note: I want to use map javascript method to add new object inside inner categories which will contain new object subcat3 which further contains all group object inside "group".

[
   {
      "id":"presentation",
      "categories":[
         {
            "id":"cat1",
            "categories":[
               {
                  "id":"subcat1",
                  "name":"subcat1",
                  "group":[
                     {
                        "id":"group1",
                        "name":"group1"
                     },
                     {
                        "id":"group2",
                        "name":"group2"
                     }
                  ]
               },
               {
                  "id":"subcat2",
                  "name":"subcat2",
                  "group":[
                     {
                        "id":"group3",
                        "name":"group3"
                     }
                  ]
               }
            ]
         }
      ]
   }
]

And the result I need::

[
   {
      "id":"presentation",
      "categories":[
         {
            "id":"cat1",
            "categories":[
               {
                  "id":"subcat1",
                  "name":"subcat1",
                  "group":[
                     {
                        "id":"group1",
                        "name":"group1"
                     },
                     {
                        "id":"group2",
                        "name":"group2"
                     }
                  ]
               },
               {
                  "id":"subcat2",
                  "name":"subcat2",
                  "group":[
                     {
                        "id":"group3",
                        "name":"group3"
                     }
                  ]
               },
               {
                  "id":"subcat3",
                  "name":"subcat3",
                  "group":[
                     {
                        "id":"group1",
                        "name":"group1"
                     },
                     {
                        "id":"group2",
                        "name":"group2"
                     },
                     {
                        "id":"group3",
                        "name":"group3"
                     }
                  ]
               }
            ]
         }
      ]
   }
]

CodePudding user response：

If you want to use map for sure, then you can follow below approach.

Logic

Map throgh the nodes in input array
Map through categories in each node
Map through categories in each category
Map through each group in that category.

From the array generated bu that, flat that array with level 3 and push to your desired node.

const input = [{"id":"presentation","categories":[{"id":"cat1","categories":[{"id":"subcat1","name":"subcat1","group":[{"id":"group1","name":"group1"},{"id":"group2","name":"group2"}]},{"id":"subcat2","name":"subcat2","group":[{"id":"group3","name":"group3"}]}]}]}];
const newCat = input.map((ipCategory) => ipCategory.categories.map((category) => category.categories.map((innerCategory) => innerCategory.group.map((group) => group))));
const groups = newCat.flat(3);
input[0].categories[0].categories.push({
  id:"subcat3",
  name:"subcat3",
  group: groups
});
console.log(input);

CodePudding user response：

const input = [{"id":"presentation","categories":[{"id":"cat1","categories":[{"id":"subcat1","name":"subcat1","group":[{"id":"group1","name":"group1"},{"id":"group2","name":"group2"}]},{"id":"subcat2","name":"subcat2","group":[{"id":"group3","name":"group3"}]}]}]}];

const newInput = input.reduce((a,c) => {
    const modified = c.categories.map((category, id) => {
    return({
        ...category,
        'categories': [
            ...category.categories,
            { id: 'subcat3', name: 'subcat3', groupings: category.categories.flatMap(({ group }) => group) }
        ]
       });
    });
    return [{
        ...c,
        categories: c.categories.map((i, ind) => ({ ...modified[ind]}))
    }];
}, []);