endpoint returning tree of categories

app/service/menuService/menuService.go

@@ -1,6 +1,12 @@
 package menuService
 
-import "git.ma-al.com/goc_daniel/b2b/repository/categoriesRepo"
+import (
+	"sort"
+
+	"git.ma-al.com/goc_daniel/b2b/app/model"
+	"git.ma-al.com/goc_daniel/b2b/app/utils/responseErrors"
+	"git.ma-al.com/goc_daniel/b2b/repository/categoriesRepo"
+)
 
 type MenuService struct {
 	categoriesRepo categoriesRepo.UICategoriesRepo
@@ -12,35 +18,73 @@ func New() *MenuService {
 	}
 }
 
-func (s *MenuService) GetMenu() (string, error) {
-	// var menu_json string
+func (s *MenuService) GetMenu(id_shop uint, id_lang uint) (model.Category, error) {
+	all_categories, err := s.categoriesRepo.GetAllCategories(id_shop, id_lang)
+	if err != nil {
+		return model.Category{}, err
+	}
 
-	// products, err := s.listProductsRepo.GetListing(id_shop, id_lang, p, filters)
-	// if err != nil {
-	// 	return products, err
-	// }
+	// find the root
+	root_index := 0
+	root_found := false
+	for i := 0; i < len(all_categories); i++ {
+		if all_categories[i].IsRoot == 1 {
+			root_index = i
+			root_found = true
+			break
+		}
+	}
+	if !root_found {
+		return model.Category{}, responseErrors.ErrNoRootFound
+	}
 
-	// var loopErr error
-	// parallel.ForEach(products.Items, func(t model.Product, i int) {
-	// 	// products.Items[i].PriceTaxed *= currRate.Rate.InexactFloat64()
-	// 	// products.Items[i].PriceTaxed = tiny_util.RoundUpMonetary(products.Items[i].PriceTaxed)
+	// now create the children and reorder them according to position
+	id_to_index := make(map[uint]int)
+	for i := 0; i < len(all_categories); i++ {
+		id_to_index[all_categories[i].CategoryID] = i
+	}
 
-	// 	if products.Items[i].Name.IsNull() {
-	// 		translation, err := s.listProductsRepo.GetTranslation(ctx, products.Items[i].ID, defaults.DefaultLanguageID)
-	// 		if err != nil {
-	// 			loopErr = err
-	// 			return
-	// 		}
-	// 		products.Items[i].Name = nullable.FromPrimitiveString(translation.Name)
-	// 		products.Items[i].DescriptionShort = nullable.FromPrimitiveString(translation.DescriptionShort)
-	// 		products.Items[i].LinkRewrite = nullable.FromPrimitiveString(translation.LinkRewrite)
-	// 	}
-	// })
-	// if loopErr != nil {
-	// 	return products, errs.Handled(span, loopErr, errs.InternalError, errs.ERR_TODO)
-	// }
+	children_indices := make(map[int][]ChildWithPosition)
+	for i := 0; i < len(all_categories); i++ {
+		parent_index := id_to_index[all_categories[i].ParentID]
+		children_indices[parent_index] = append(children_indices[parent_index], ChildWithPosition{Index: i, Position: all_categories[i].Position})
+	}
 
-	// return products, nil
+	for key := range children_indices {
+		sort.Sort(ByPosition(children_indices[key]))
+	}
 
-	return "", nil
+	// finally, create the tree
+	tree := s.createTree(root_index, &all_categories, &children_indices)
+
+	return tree, nil
 }
+
+func (s *MenuService) createTree(index int, all_categories *([]model.ScannedCategory), children_indices *(map[int][]ChildWithPosition)) model.Category {
+	node := s.scannedToNormalCategory((*all_categories)[index])
+
+	for i := 0; i < len((*children_indices)[index]); i++ {
+		node.Subcategories = append(node.Subcategories, s.createTree((*children_indices)[index][i].Index, all_categories, children_indices))
+	}
+
+	return node
+}
+
+func (s *MenuService) scannedToNormalCategory(scanned model.ScannedCategory) model.Category {
+	var normal model.Category
+	normal.Active = scanned.Active
+	normal.CategoryID = scanned.CategoryID
+	normal.Name = scanned.Name
+	normal.Subcategories = []model.Category{}
+	return normal
+}
+
+type ChildWithPosition struct {
+	Index    int
+	Position uint
+}
+type ByPosition []ChildWithPosition
+
+func (a ByPosition) Len() int           { return len(a) }
+func (a ByPosition) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a ByPosition) Less(i, j int) bool { return a[i].Position < a[j].Position }