feat: Introduce Nullable type for optional fields and update user DTOs accordingly

backend/Makefile

@@ -99,6 +99,6 @@ swagger:
 # Generate TypeScript types
 generate-ts:
 	@echo "Generating TypeScript types..."
-	@tygo generate
+	@go run scripts/fix_tygo.go
 	@echo "TypeScript types generated"
 

backend/internal/api/handlers/user_handler.go

@@ -182,12 +182,17 @@ func (h *UserHandler) UpdateUser(c *gin.Context) {
 		update.Role = userUpdateDTO.Role
 	}
 	if userUpdateDTO.CompanyID != nil {
-		companyID, err := models.ULIDWrapperFromString(*userUpdateDTO.CompanyID)
+		if userUpdateDTO.CompanyID.Valid {
+			companyID, err := models.ULIDWrapperFromString(*userUpdateDTO.CompanyID.Value)
 			if err != nil {
 				utils.BadRequestResponse(c, "Invalid company ID format")
 				return
 			}
 			update.CompanyID = &companyID
+		} else {
+			update.CompanyID = nil
+
+		}
 	}
 	if userUpdateDTO.HourlyRate != nil {
 		update.HourlyRate = userUpdateDTO.HourlyRate
@@ -393,8 +398,8 @@ func convertUserToDTO(user *models.User) dto.UserDto {
 
 func convertCreateDTOToModel(dto dto.UserCreateDto) models.UserCreate {
 	var companyID models.ULIDWrapper
-	if dto.CompanyID != nil {
+	if dto.CompanyID != nil && dto.CompanyID.Valid {
-		companyID, _ = models.ULIDWrapperFromString(*dto.CompanyID) // Ignoring error, validation happens in the model
+		companyID, _ = models.ULIDWrapperFromString(*dto.CompanyID.Value) // Ignoring error, validation happens in the model
 	}
 
 	return models.UserCreate{

backend/internal/dtos/helper/nullstring.go

@@ -1,4 +1,4 @@
-package dto
+package helper
 
 import "encoding/json"
 

backend/internal/dtos/user_dto.go

@@ -2,6 +2,8 @@ package dto
 
 import (
 	"time"
+
+	"github.com/timetracker/backend/internal/types"
 )
 
 type UserDto struct {
@@ -19,7 +21,7 @@ type UserCreateDto struct {
 	Email      string                  `json:"email" example:"test@example.com"`
 	Password   string                  `json:"password" example:"password123"`
 	Role       string                  `json:"role" example:"admin"`
-	CompanyID  *string `json:"companyId" example:"01HGW2BBG0000000000000000"`
+	CompanyID  *types.Nullable[string] `json:"companyId" example:"01HGW2BBG0000000000000000"`
 	HourlyRate float64                 `json:"hourlyRate" example:"50.00"`
 }
 
@@ -31,6 +33,6 @@ type UserUpdateDto struct {
 	Email        *string                 `json:"email" example:"test@example.com"`
 	Password     *string                 `json:"password" example:"password123"`
 	Role         *string                 `json:"role" example:"admin"`
-	CompanyID    *string    `json:"companyId" example:"01HGW2BBG0000000000000000"`
+	CompanyID    *types.Nullable[string] `json:"companyId" example:"01HGW2BBG0000000000000000"`
 	HourlyRate   *float64                `json:"hourlyRate" example:"50.00"`
 }

backend/internal/types/nullable.go

@@ -0,0 +1,48 @@
+package types
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+// Nullable[T] - Generischer Typ für optionale Werte (nullable fields)
+type Nullable[T any] struct {
+	Value *T   // Der tatsächliche Wert (kann nil sein)
+	Valid bool // Gibt an, ob der Wert gesetzt wurde
+}
+
+// NewNullable erstellt eine gültige Nullable-Instanz
+func NewNullable[T any](value T) Nullable[T] {
+	return Nullable[T]{Value: &value, Valid: true}
+}
+
+// Null erstellt eine leere Nullable-Instanz (ungesetzt)
+func Null[T any]() Nullable[T] {
+	return Nullable[T]{Valid: false}
+}
+
+// MarshalJSON - Serialisiert `Nullable[T]` korrekt ins JSON-Format
+func (n Nullable[T]) MarshalJSON() ([]byte, error) {
+	if !n.Valid {
+		return []byte("null"), nil // Wenn nicht valid, dann NULL
+	}
+	return json.Marshal(n.Value) // Serialisiert den tatsächlichen Wert
+}
+
+// UnmarshalJSON - Deserialisiert JSON in `Nullable[T]`
+func (n *Nullable[T]) UnmarshalJSON(data []byte) error {
+	if string(data) == "null" {
+		n.Valid = true // Wert wurde gesetzt, aber auf NULL
+		n.Value = nil  // Explizit NULL setzen
+		return nil
+	}
+
+	var v T
+	if err := json.Unmarshal(data, &v); err != nil {
+		return fmt.Errorf("invalid JSON for Nullable: %w", err)
+	}
+
+	n.Value = &v
+	n.Valid = true
+	return nil
+}

backend/scripts/fix_tygo.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+const (
+	dtoFilePath     = "../frontend/src/types/dto.ts"
+	importStatement = `import { Nullable } from "./nullable";`
+)
+
+func main() {
+	// Run Tygo first
+	fmt.Println("🔄 Running tygo...")
+	if err := runTygo(); err != nil {
+		fmt.Println("❌ Error running tygo:", err)
+		os.Exit(1)
+	}
+
+	// Read dto.ts file
+	content, err := os.ReadFile(dtoFilePath)
+	if err != nil {
+		fmt.Println("❌ Could not read dto.ts:", err)
+		os.Exit(1)
+	}
+
+	// Convert to string
+	dtoContent := string(content)
+
+	// Check if import already exists
+	if strings.Contains(dtoContent, importStatement) {
+		fmt.Println("ℹ️ Import already exists in dto.ts, skipping.")
+		return
+	}
+
+	// Add import statement at the beginning
+	newContent := importStatement + "\n" + dtoContent
+	if err := os.WriteFile(dtoFilePath, []byte(newContent), 0644); err != nil {
+		fmt.Println("❌ Error writing dto.ts:", err)
+		os.Exit(1)
+	}
+
+	fmt.Println("✅ Successfully added Nullable<T> import to dto.ts")
+}
+
+// Runs Tygo command
+func runTygo() error {
+	cmd := "tygo"
+	output, err := exec.Command(cmd, "generate").CombinedOutput()
+	if err != nil {
+		fmt.Println("Tygo output:", string(output))
+		return err
+	}
+	if len(output) > 0 {
+		fmt.Println("Tygo output:", string(output))
+		return nil
+	}
+	return nil
+}

backend/tygo.yaml

@@ -3,5 +3,5 @@ packages:
     type_mappings:
       "time.Time": "string"
       "ulid.ULID": "string"
-      "null.String": "null | string"
+      "types.Nullable": "Nullable"
     output_path: ../frontend/src/types/dto.ts

frontend/src/types/dto.ts

@@ -1,3 +1,4 @@
+import { Nullable } from "./nullable";
 // Code generated by tygo. DO NOT EDIT.
 
 //////////
@@ -167,7 +168,7 @@ export interface UserCreateDto {
   email: string;
   password: string;
   role: string;
-  companyId?: string;
+  companyId?: Nullable<string>;
   hourlyRate: number /* float64 */;
 }
 export interface UserUpdateDto {
@@ -178,6 +179,6 @@ export interface UserUpdateDto {
   email?: string;
   password?: string;
   role?: string;
-  companyId?: string;
+  companyId?: Nullable<string>;
   hourlyRate?: number /* float64 */;
 }

frontend/src/types/nullable.ts

@@ -0,0 +1 @@
+export type Nullable<T> = T | null;