add get card method

internal/modules/storage/storage_file/storage.go

@@ -0,0 +1,97 @@
+package storage_file
+
+import (
+	"cake_crm/internal/modules/storage"
+	crm "cake_crm/proto"
+	"context"
+	"encoding/json"
+	"errors"
+	"os"
+)
+
+var (
+	ErrProductNotFound = errors.New("product not found")
+)
+
+type storageFile struct{}
+
+func NewStorageFile() storage.IStorage {
+	return &storageFile{}
+}
+
+func (s *storageFile) GetCatalog(_ context.Context) ([]*crm.Category, error) {
+	data, err := os.ReadFile("resources/catalog.json")
+	if err != nil {
+		return nil, err
+	}
+	var res []*crm.Category
+	if err := json.Unmarshal(data, &res); err != nil {
+		return nil, err
+	}
+	return res, nil
+}
+
+func (s *storageFile) GetPositions(_ context.Context, id int64) ([]*crm.Product, error) {
+	data, err := os.ReadFile("resources/products.json")
+	if err != nil {
+		return nil, err
+	}
+	var products []*crm.Product
+	if err := json.Unmarshal(data, &products); err != nil {
+		return nil, err
+	}
+	res := make([]*crm.Product, 0, len(products))
+	for _, product := range products {
+		if id == 0 || product.Category == id {
+			res = append(res, product)
+		}
+	}
+	return res, nil
+}
+
+func (s *storageFile) GetProduct(_ context.Context, id int64) (*crm.Product, error) {
+	data, err := os.ReadFile("resources/products.json")
+	if err != nil {
+		return nil, err
+	}
+	var products []*crm.Product
+	if err := json.Unmarshal(data, &products); err != nil {
+		return nil, err
+	}
+	for _, product := range products {
+		if product.Id == id {
+			return product, nil
+		}
+	}
+	return nil, ErrProductNotFound
+}
+
+func (s *storageFile) GetBreadcrumbs(_ context.Context, id int64) ([]*crm.Category, error) {
+	data, err := os.ReadFile("resources/catalog.json")
+	if err != nil {
+		return nil, err
+	}
+	var categories []*crm.Category
+	if err := json.Unmarshal(data, &categories); err != nil {
+		return nil, err
+	}
+	return getBreadcrumbs(categories, id), nil
+}
+
+func getBreadcrumbs(categories []*crm.Category, id int64) []*crm.Category {
+	for _, category := range categories {
+		if category.Id == id {
+			category.Children = nil
+			return []*crm.Category{category}
+		}
+		breadcrumbs := getBreadcrumbs(category.Children, id)
+		if len(breadcrumbs) != 0 {
+			res := make([]*crm.Category, 0, len(breadcrumbs)+1)
+			category.Children = nil
+			res = append(res, category)
+			res = append(res, breadcrumbs...)
+			return res
+		}
+	}
+	return nil
+}