var getStructureTree = function getStructureTree(highLevelArray, leftArray) {
  if (leftArray.length) {
  	var subLeft = leftArray;
    
    highLevelArray.map(function(v) {
    	v.subcategories.map(function(value, key) {
      	v.subcategories[key].subcategories = leftArray.filter(function(subValue) {
          if (subValue.parent === value.id) {
            _.remove(subLeft, subValue);
          }
        	return subValue.parent === value.id;
      	});
    	})
    });

    console.log('subLeft', subLeft);
		//getStructureTree(highLevelArray, subLeft);
  }
  return highLevelArray;
}

var categories = [{id:1, parent:null},{id:2, parent:1},{id:3, parent:null},
                 {id:4, parent:2},{id:5, parent:2},{id:6, parent:3},
                 {id:7, parent:null},{id:8, parent:7},{id:9, parent:5}];

var topParentCategories = categories.filter(function(value) {  return value.parent === null; });
var categoriesLeft = categories.filter(function(value) {  return value.parent !== null; });

var subLeft = categoriesLeft;

topParentCategories.map(function(value, key) {   
  topParentCategories[key].subcategories = categoriesLeft.filter(function(subValue) {
    if (subValue.parent === value.id) {
      _.remove(subLeft, subValue);
    }

    return subValue.parent === value.id;
  });
});

console.log('subLeft', subLeft);
getStructureTree(topParentCategories, subLeft);
console.log('topParentCategories', topParentCategories);