const all = [
  {
    name: 'Folder1',
    children: [
      {
        name: 'subfolder 1.1',
        children: [
          {
            name: 'item 1.1.1',
          }, {
            name: 'item 1.1.2',
          },
        ],
      },
      {
        name: 'subfolder 1.2',
        children: [
          {
            name: 'item 1.2.1',
          },
          {
            name: 'item 1.2.2',
          },
        ],
      },
    ],
  },
  {
    name: 'Folder2',
    children: [
      {
        name: 'subfolder 2.1',
        children: [
          {
            name: 'Item 2.1.1',
          },
          {
            name: 'Item 2.1.2',
          },
        ],
      },
      {
        name: 'subfolder 2.2',
        children: [
          {
            name: 'Item 2.2.1',
          },
          {
            name: 'Item 2.2.2',
          },
        ],
      },
    ],
  },
  {
    name: 'Folder3',
    children: [
      {
        name: 'subfolder 3.1',
        children: [
          {
            name: 'Item 3.1.1',
          },
          {
            name: 'Item 3.1.2',
          },
        ],
      },
      {
        name: 'subfolder 3.2',
        children: [
          {
            name: 'Item 3.2.1',
          },
          {
            name: 'Item 3.2.2',
          },
        ],
      },
    ],
  },
]

function applyFilters(data, filters) {
  function applyFilter(items = [], filter) {
    const filtered = []

    for (const item of items) {
      if (item.name.indexOf(filter) !== -1) {
        filtered.push(item)
      } else {
        const children = applyFilter(item.children, filter)

        if (children.length) {
          filtered.push({
            ...item,
            children,
          })
        }
      }
    }

    return filtered
  }

  let result = data

  for (const filter of filters) {
    result = applyFilter(result, filter)
  }

  return result
}


// test suites

function it(message, expression, result) {
  if (expression === result) {
    return console.log(`${message}: passed. Result: ${expression}\n\n`)
  }

  throw Error(`${message}: failed. Expected: "${result}". Actual: "${expression}"`)
}

it('JSON.stringify(applyFilters(all, [\'3.2.2\']))', JSON.stringify(applyFilters(all, ['3.2.2'])), '[{"name":"Folder3","children":[{"name":"subfolder 3.2","children":[{"name":"Item 3.2.2"}]}]}]')

it('JSON.stringify(applyFilters(all, [\'3\', \'2\']).filter(f => f.children.length))', JSON.stringify(applyFilters(all, ['3', '2']).filter(f => f.children.length)), '[{"name":"Folder3","children":[{"name":"subfolder 3.1","children":[{"name":"Item 3.1.2"}]},{"name":"subfolder 3.2","children":[{"name":"Item 3.2.1"},{"name":"Item 3.2.2"}]}]}]')

it('JSON.stringify(applyFilters(all, [\'.1\']).filter(f => f.children.length))', JSON.stringify(applyFilters(all, ['.1']).filter(f => f.children.length)), '[{"name":"Folder1","children":[{"name":"subfolder 1.1","children":[{"name":"item 1.1.1"},{"name":"item 1.1.2"}]},{"name":"subfolder 1.2","children":[{"name":"item 1.2.1"}]}]},{"name":"Folder2","children":[{"name":"subfolder 2.1","children":[{"name":"Item 2.1.1"},{"name":"Item 2.1.2"}]},{"name":"subfolder 2.2","children":[{"name":"Item 2.2.1"}]}]},{"name":"Folder3","children":[{"name":"subfolder 3.1","children":[{"name":"Item 3.1.1"},{"name":"Item 3.1.2"}]},{"name":"subfolder 3.2","children":[{"name":"Item 3.2.1"}]}]}]')

it('JSON.stringify(applyFilters(all, [\'Folder2\', \'1.1\']).filter(f => f.children.length))', JSON.stringify(applyFilters(all, ['Folder2', '1.1']).filter(f => f.children.length)), '[{"name":"Folder2","children":[{"name":"subfolder 2.1","children":[{"name":"Item 2.1.1"}]}]}]')

it('JSON.stringify(applyFilters(all, [\'Folder2\', \'2.1\']).filter(f => f.children.length))', JSON.stringify(applyFilters(all, ['Folder2', '2.1']).filter(f => f.children.length)), '[{"name":"Folder2","children":[{"name":"subfolder 2.1","children":[{"name":"Item 2.1.1"},{"name":"Item 2.1.2"}]},{"name":"subfolder 2.2","children":[{"name":"Item 2.2.1"}]}]}]')