Enhance Customer Service with Company Loading Logic

- Added functionality to load associated companies for customers during registration and updates, improving the completeness of customer responses.
- Implemented error logging for failures in loading companies, ensuring better traceability of issues.
- Updated the response structure to include company information in customer responses, enhancing the API's usability and data richness.
- Removed the unused GetProfile method to streamline the service layer and improve code maintainability.

internal/customer/service.go

@@ -130,6 +130,13 @@ func (s *customerService) Register(ctx context.Context, form *CreateCustomerForm
 		})
 		return nil, err
 	}
+	companies, err := s.loadCompaniesForCustomer(ctx, customer)
+	if err != nil {
+		s.logger.Error("Failed to load companies for customer", map[string]interface{}{
+			"error":       err.Error(),
+			"customer_id": customer.ID,
+		})
+	}
 
 	s.logger.Info("Customer created successfully", map[string]interface{}{
 		"customer_id": customer.ID,
@@ -147,7 +154,7 @@ func (s *customerService) Register(ctx context.Context, form *CreateCustomerForm
 		UserID:    customer.ID.Hex(),
 	})
 
-	return customer.ToResponse(nil), nil
+	return customer.ToResponse(companies), nil
 }
 
 // GetByID retrieves a customer by ID
@@ -260,7 +267,17 @@ func (s *customerService) GetCustomersByCompanies(ctx context.Context, companies
 
 	var customerResponses []*CustomerResponse
 	for _, customer := range customers {
-		customerResponses = append(customerResponses, customer.ToResponse(nil))
+		companies := make([]*CompanySummary, 0)
+		if len(customer.Companies) > 0 {
+			companies, err = s.loadCompaniesForCustomer(ctx, &customer)
+			if err != nil {
+				s.logger.Error("Failed to load companies for customer", map[string]interface{}{
+					"error":       err.Error(),
+					"customer_id": customer.ID,
+				})
+			}
+		}
+		customerResponses = append(customerResponses, customer.ToResponse(companies))
 	}
 
 	return &CustomerListResponse{
@@ -299,21 +316,15 @@ func (s *customerService) Update(ctx context.Context, id string, form *UpdateCus
 	}
 
 	// Handle company assignments
+	companies := make([]*CompanySummary, 0)
 	if len(form.Companies) > 0 {
-		// Verify that all company IDs exist
-		var validCompanies []string
-		for _, companyID := range form.Companies {
-			_, err := s.companyService.GetByID(ctx, companyID)
-			if err != nil {
-				s.logger.Error("Invalid company ID provided in update", map[string]interface{}{
-					"error":      err.Error(),
-					"company_id": companyID,
-				})
-				return nil, errors.New("invalid company ID: " + companyID)
-			}
-			validCompanies = append(validCompanies, companyID)
+		companies, err = s.loadCompaniesForCustomer(ctx, customer)
+		if err != nil {
+			s.logger.Error("Failed to load companies for customer", map[string]interface{}{
+				"error":       err.Error(),
+				"customer_id": customer.ID,
+			})
 		}
-		customer.Companies = validCompanies
 	}
 
 	if form.FullName != nil {
@@ -344,7 +355,7 @@ func (s *customerService) Update(ctx context.Context, id string, form *UpdateCus
 		"email":       customer.Email,
 	})
 
-	return customer.ToResponse(nil), nil
+	return customer.ToResponse(companies), nil
 }
 
 // Delete deletes a customer (soft delete)
@@ -718,29 +729,6 @@ func (s *customerService) RefreshToken(ctx context.Context, refreshToken string)
 	}, nil
 }
 
-// GetProfile retrieves customer profile information
-func (s *customerService) GetProfile(ctx context.Context, customerID string) (*Customer, error) {
-	s.logger.Info("Getting customer profile", map[string]interface{}{
-		"customer_id": customerID,
-	})
-
-	customer, err := s.repository.GetByID(ctx, customerID)
-	if err != nil {
-		s.logger.Error("Failed to get customer profile", map[string]interface{}{
-			"error":       err.Error(),
-			"customer_id": customerID,
-		})
-		return nil, errors.New("customer not found")
-	}
-
-	s.logger.Info("Customer profile retrieved successfully", map[string]interface{}{
-		"customer_id":   customerID,
-		"customer_type": string(customer.Type),
-	})
-
-	return customer, nil
-}
-
 // GetProfileWithCompanies retrieves customer profile information including companies
 func (s *customerService) GetProfileWithCompanies(ctx context.Context, customerID string) (*CustomerResponse, error) {
 	s.logger.Info("Getting customer profile with companies", map[string]interface{}{