Remove timezone from User model and pass as request parameter

Timezone is now sent from the client on each request that needs it,
instead of storing it in the database. This simplifies the model and
allows timezone to be dynamic (useful for traveling users).

Changes:
- Remove timezone field from User entity
- Remove timezone from user registration
- GET /habits/today now requires ?timezone= query param
- Add migration to drop timezone column from database
- Update related tests

cmd/api/main.go

@@ -114,7 +114,7 @@ func main() {
 	unmarkHandler := commands.NewUnmarkHabitHandler(habitRepo, entryRepo)
 
 	authHandlers := httpInfra.NewAuthHandlers(registerHandler, loginHandler, refreshTokenHandler, revokeTokenHandler, revokeAllTokensHandler, verifyEmailHandler, resendVerificationEmailHandler, requestPasswordResetHandler, resetPasswordHandler, jwtService, refreshTokenRepo, refreshTokenExpiry, translator)
-	habitHandlers := httpInfra.NewHabitHandlers(createHandler, getTodaysHandler, getUserHabitsHandler, getHabitByIDHandler, getHabitEntriesHandler, updateHandler, archiveHandler, markHandler, unmarkHandler, userRepo, translator)
+	habitHandlers := httpInfra.NewHabitHandlers(createHandler, getTodaysHandler, getUserHabitsHandler, getHabitByIDHandler, getHabitEntriesHandler, updateHandler, archiveHandler, markHandler, unmarkHandler, translator)
 	statsHandlers := httpInfra.NewStatsHandlers(getHabitStatsHandler, translator)
 	healthHandlers := httpInfra.NewHealthHandlers(db.Conn())
 	userHandlers := httpInfra.NewUserHandlers(deleteUserHandler, translator)

internal/application/commands/delete_user_test.go

@@ -48,7 +48,7 @@ func TestDeleteUserHandler_Success(t *testing.T) {
 
 	repo := &mockDeleteUserRepo{
 		findByIDFunc: func(ctx context.Context, id string) (*entities.User, error) {
-			user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+			user := entities.NewUser("test@example.com", "hashedPassword")
 			user.ID = id
 			return user, nil
 		},
@@ -112,7 +112,7 @@ func TestDeleteUserHandler_DeleteError(t *testing.T) {
 
 	repo := &mockDeleteUserRepo{
 		findByIDFunc: func(ctx context.Context, id string) (*entities.User, error) {
-			user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+			user := entities.NewUser("test@example.com", "hashedPassword")
 			user.ID = id
 			return user, nil
 		},

internal/application/commands/register_user.go

@@ -17,7 +17,6 @@ import (
 type RegisterUserCommand struct {
 	Email    string
 	Password string
-	Timezone string
 }
 
 type RegisterUserResult struct {
@@ -57,7 +56,7 @@ func (h *RegisterUserHandler) Handle(ctx context.Context, cmd RegisterUserComman
 		return nil, errors.ErrRegistrationClosed
 	}
 
-	if err := validation.ValidateRegistration(cmd.Email, cmd.Password, cmd.Timezone); err != nil {
+	if err := validation.ValidateRegistration(cmd.Email, cmd.Password); err != nil {
 		return nil, fmt.Errorf("%w: %v", errors.ErrInvalidInput, err)
 	}
 
@@ -71,7 +70,7 @@ func (h *RegisterUserHandler) Handle(ctx context.Context, cmd RegisterUserComman
 		return nil, err
 	}
 
-	user := entities.NewUser(cmd.Email, hashedPassword, cmd.Timezone)
+	user := entities.NewUser(cmd.Email, hashedPassword)
 
 	emailVerificationRequired := false
 	if h.emailService != nil {

internal/application/commands/register_user_test.go

@@ -74,7 +74,6 @@ func TestRegisterUserHandler_Success(t *testing.T) {
 	cmd := RegisterUserCommand{
 		Email:    "test@example.com",
 		Password: "Secure123!",
-		Timezone: "UTC",
 	}
 
 	result, err := handler.Handle(context.Background(), cmd)
@@ -97,10 +96,6 @@ func TestRegisterUserHandler_Success(t *testing.T) {
 	if createdUser.Email != cmd.Email {
 		t.Errorf("expected email %q, got %q", cmd.Email, createdUser.Email)
 	}
-
-	if createdUser.Timezone != cmd.Timezone {
-		t.Errorf("expected timezone %q, got %q", cmd.Timezone, createdUser.Timezone)
-	}
 }
 
 func TestRegisterUserHandler_InvalidEmail(t *testing.T) {
@@ -125,7 +120,6 @@ func TestRegisterUserHandler_InvalidEmail(t *testing.T) {
 			cmd := RegisterUserCommand{
 				Email:    tt.email,
 				Password: "Secure123!",
-				Timezone: "UTC",
 			}
 
 			_, err := handler.Handle(context.Background(), cmd)
@@ -160,38 +154,6 @@ func TestRegisterUserHandler_InvalidPassword(t *testing.T) {
 			cmd := RegisterUserCommand{
 				Email:    "test@example.com",
 				Password: tt.password,
-				Timezone: "UTC",
-			}
-
-			_, err := handler.Handle(context.Background(), cmd)
-			if !errors.Is(err, appErrors.ErrInvalidInput) {
-				t.Errorf("expected ErrInvalidInput, got %v", err)
-			}
-		})
-	}
-}
-
-func TestRegisterUserHandler_InvalidTimezone(t *testing.T) {
-	repo := &mockUserRepo{}
-	hasher := &mockPasswordHasher{}
-	handler := NewRegisterUserHandler(repo, hasher, nil, "", "open", false)
-
-	tests := []struct {
-		name     string
-		timezone string
-	}{
-		{"empty timezone", ""},
-		{"invalid timezone", "InvalidTimezone"},
-		{"numeric format", "GMT+1"},
-		{"partial timezone", "America"},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			cmd := RegisterUserCommand{
-				Email:    "test@example.com",
-				Password: "Secure123!",
-				Timezone: tt.timezone,
 			}
 
 			_, err := handler.Handle(context.Background(), cmd)
@@ -203,7 +165,7 @@ func TestRegisterUserHandler_InvalidTimezone(t *testing.T) {
 }
 
 func TestRegisterUserHandler_EmailAlreadyExists(t *testing.T) {
-	existingUser := entities.NewUser("test@example.com", "hashed", "UTC")
+	existingUser := entities.NewUser("test@example.com", "hashed")
 	repo := &mockUserRepo{
 		findByEmailFunc: func(ctx context.Context, email string) (*entities.User, error) {
 			return existingUser, nil
@@ -215,7 +177,6 @@ func TestRegisterUserHandler_EmailAlreadyExists(t *testing.T) {
 	cmd := RegisterUserCommand{
 		Email:    "test@example.com",
 		Password: "Secure123!",
-		Timezone: "UTC",
 	}
 
 	_, err := handler.Handle(context.Background(), cmd)
@@ -237,7 +198,6 @@ func TestRegisterUserHandler_PasswordHashingError(t *testing.T) {
 	cmd := RegisterUserCommand{
 		Email:    "test@example.com",
 		Password: "Secure123!",
-		Timezone: "UTC",
 	}
 
 	_, err := handler.Handle(context.Background(), cmd)
@@ -259,7 +219,6 @@ func TestRegisterUserHandler_RepositoryError(t *testing.T) {
 	cmd := RegisterUserCommand{
 		Email:    "test@example.com",
 		Password: "Secure123!",
-		Timezone: "UTC",
 	}
 
 	_, err := handler.Handle(context.Background(), cmd)
@@ -283,7 +242,6 @@ func TestRegisterUserHandler_EdgeCases(t *testing.T) {
 			RegisterUserCommand{
 				Email:    "user+tag@example.com",
 				Password: "Secure123!",
-				Timezone: "UTC",
 			},
 			nil,
 		},
@@ -292,16 +250,6 @@ func TestRegisterUserHandler_EdgeCases(t *testing.T) {
 			RegisterUserCommand{
 				Email:    "user@mail.example.com",
 				Password: "Secure123!",
-				Timezone: "UTC",
-			},
-			nil,
-		},
-		{
-			"complex timezone",
-			RegisterUserCommand{
-				Email:    "user@example.com",
-				Password: "Secure123!",
-				Timezone: "America/Argentina/Buenos_Aires",
 			},
 			nil,
 		},
@@ -310,7 +258,6 @@ func TestRegisterUserHandler_EdgeCases(t *testing.T) {
 			RegisterUserCommand{
 				Email:    "user@example.com",
 				Password: "Sëcure123!",
-				Timezone: "UTC",
 			},
 			nil,
 		},
@@ -319,7 +266,6 @@ func TestRegisterUserHandler_EdgeCases(t *testing.T) {
 			RegisterUserCommand{
 				Email:    "user@example.com",
 				Password: "ValidP@ss1" + string(make([]byte, 100)),
-				Timezone: "UTC",
 			},
 			nil,
 		},
@@ -342,7 +288,6 @@ func TestRegisterUserHandler_ClosedRegistration(t *testing.T) {
 	cmd := RegisterUserCommand{
 		Email:    "test@example.com",
 		Password: "Secure123!",
-		Timezone: "UTC",
 	}
 
 	_, err := handler.Handle(context.Background(), cmd)

internal/application/commands/reset_password_test.go

@@ -98,7 +98,7 @@ func (m *mockResetPasswordHasher) Compare(hashedPassword, password string) error
 }
 
 func TestResetPasswordHandler_Success(t *testing.T) {
-	user := entities.NewUser("test@example.com", "old_hash", "UTC")
+	user := entities.NewUser("test@example.com", "old_hash")
 	user.ID = "user-123"
 
 	resetToken := entities.NewPasswordResetToken(
@@ -340,7 +340,7 @@ func TestResetPasswordHandler_UserNotFound(t *testing.T) {
 }
 
 func TestResetPasswordHandler_HashingError(t *testing.T) {
-	user := entities.NewUser("test@example.com", "old_hash", "UTC")
+	user := entities.NewUser("test@example.com", "old_hash")
 	user.ID = "user-123"
 
 	resetToken := entities.NewPasswordResetToken(

internal/application/commands/verify_email_test.go

@@ -67,7 +67,7 @@ func TestVerifyEmailHandler_Success(t *testing.T) {
 	token := "valid-token"
 	expiry := time.Now().Add(24 * time.Hour)
 
-	user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+	user := entities.NewUser("test@example.com", "hashedPassword")
 	user.ID = "user-123"
 	user.EmailVerified = false
 	user.EmailVerificationToken = &token
@@ -148,7 +148,7 @@ func TestVerifyEmailHandler_AlreadyVerified(t *testing.T) {
 	token := "valid-token"
 	expiry := time.Now().Add(24 * time.Hour)
 
-	user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+	user := entities.NewUser("test@example.com", "hashedPassword")
 	user.ID = "user-123"
 	user.EmailVerified = true
 	user.EmailVerificationToken = &token
@@ -176,7 +176,7 @@ func TestVerifyEmailHandler_ExpiredToken(t *testing.T) {
 	token := "expired-token"
 	expiry := time.Now().Add(-1 * time.Hour)
 
-	user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+	user := entities.NewUser("test@example.com", "hashedPassword")
 	user.ID = "user-123"
 	user.EmailVerified = false
 	user.EmailVerificationToken = &token
@@ -203,7 +203,7 @@ func TestVerifyEmailHandler_ExpiredToken(t *testing.T) {
 func TestVerifyEmailHandler_NilExpiry(t *testing.T) {
 	token := "valid-token"
 
-	user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+	user := entities.NewUser("test@example.com", "hashedPassword")
 	user.ID = "user-123"
 	user.EmailVerified = false
 	user.EmailVerificationToken = &token
@@ -231,7 +231,7 @@ func TestVerifyEmailHandler_WithWelcomeEmail(t *testing.T) {
 	token := "valid-token"
 	expiry := time.Now().Add(24 * time.Hour)
 
-	user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+	user := entities.NewUser("test@example.com", "hashedPassword")
 	user.ID = "user-123"
 	user.EmailVerified = false
 	user.EmailVerificationToken = &token
@@ -277,7 +277,7 @@ func TestVerifyEmailHandler_WithoutWelcomeEmail(t *testing.T) {
 	token := "valid-token"
 	expiry := time.Now().Add(24 * time.Hour)
 
-	user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+	user := entities.NewUser("test@example.com", "hashedPassword")
 	user.ID = "user-123"
 	user.EmailVerified = false
 	user.EmailVerificationToken = &token
@@ -310,7 +310,7 @@ func TestVerifyEmailHandler_UpdateError(t *testing.T) {
 	token := "valid-token"
 	expiry := time.Now().Add(24 * time.Hour)
 
-	user := entities.NewUser("test@example.com", "hashedPassword", "UTC")
+	user := entities.NewUser("test@example.com", "hashedPassword")
 	user.ID = "user-123"
 	user.EmailVerified = false
 	user.EmailVerificationToken = &token

internal/application/queries/login_user.go

@@ -16,7 +16,6 @@ type LoginUserQuery struct {
 type LoginUserResult struct {
 	UserID string
 	Email  string
-	Timezone string
 }
 
 type LoginUserHandler struct {
@@ -52,6 +51,5 @@ func (h *LoginUserHandler) Handle(ctx context.Context, query LoginUserQuery) (*L
 	return &LoginUserResult{
 		UserID: user.ID,
 		Email:  user.Email,
-		Timezone: user.Timezone,
 	}, nil
 }

internal/application/queries/login_user_test.go

@@ -55,7 +55,7 @@ func (m *mockLoginPasswordHasher) Compare(hashedPassword, password string) error
 }
 
 func TestLoginUserHandler_Success(t *testing.T) {
-	user := entities.NewUser("test@example.com", "hashed_password", "UTC")
+	user := entities.NewUser("test@example.com", "hashed_password")
 	user.ID = "user-123"
 	user.EmailVerified = true
 
@@ -150,7 +150,7 @@ func TestLoginUserHandler_UserNotFound(t *testing.T) {
 }
 
 func TestLoginUserHandler_InvalidPassword(t *testing.T) {
-	user := entities.NewUser("test@example.com", "hashed_password", "UTC")
+	user := entities.NewUser("test@example.com", "hashed_password")
 	user.ID = "user-123"
 	user.EmailVerified = true
 
@@ -180,7 +180,7 @@ func TestLoginUserHandler_InvalidPassword(t *testing.T) {
 }
 
 func TestLoginUserHandler_EmailNotVerified(t *testing.T) {
-	user := entities.NewUser("test@example.com", "hashed_password", "UTC")
+	user := entities.NewUser("test@example.com", "hashed_password")
 	user.ID = "user-123"
 	user.EmailVerified = false
 

internal/application/queries/refresh_token.go

@@ -19,7 +19,6 @@ type RefreshTokenQuery struct {
 type RefreshTokenResult struct {
 	UserID string
 	Email  string
-	Timezone string
 }
 
 type RefreshTokenHandler struct {
@@ -59,7 +58,6 @@ func (h *RefreshTokenHandler) Handle(ctx context.Context, query RefreshTokenQuer
 	return &RefreshTokenResult{
 		UserID: user.ID,
 		Email:  user.Email,
-		Timezone: user.Timezone,
 	}, nil
 }
 

internal/application/queries/refresh_token_test.go

@@ -80,7 +80,7 @@ func TestRefreshTokenHandler_Success(t *testing.T) {
 
 	userRepo := &mockUserRepositoryForRefresh{
 		findByIDFunc: func(ctx context.Context, id string) (*entities.User, error) {
-			user := entities.NewUser("test@example.com", "hash", "UTC")
+			user := entities.NewUser("test@example.com", "hash")
 			user.ID = id
 			return user, nil
 		},

internal/domain/entities/user.go

@@ -6,7 +6,6 @@ type User struct {
 	ID                      string
 	Email                   string
 	PasswordHash            string
-	Timezone                string
 	EmailVerified           bool
 	EmailVerificationToken  *string
 	EmailVerificationExpiry *time.Time
@@ -14,15 +13,11 @@ type User struct {
 	UpdatedAt               time.Time
 }
 
-func NewUser(email, passwordHash, timezone string) *User {
+func NewUser(email, passwordHash string) *User {
 	now := time.Now()
-	if timezone == "" {
-		timezone = "UTC"
-	}
 	return &User{
 		Email:        email,
 		PasswordHash: passwordHash,
-		Timezone:     timezone,
 		CreatedAt:    now,
 		UpdatedAt:    now,
 	}

internal/domain/entities/user_test.go

@@ -8,9 +8,8 @@ import (
 func TestNewUser(t *testing.T) {
 	email := "test@example.com"
 	passwordHash := "hashed_password_123"
-	timezone := "Europe/Madrid"
 
-	user := NewUser(email, passwordHash, timezone)
+	user := NewUser(email, passwordHash)
 
 	if user.Email != email {
 		t.Errorf("Expected email %s, got %s", email, user.Email)
@@ -20,10 +19,6 @@ func TestNewUser(t *testing.T) {
 		t.Errorf("Expected password hash %s, got %s", passwordHash, user.PasswordHash)
 	}
 
-	if user.Timezone != timezone {
-		t.Errorf("Expected timezone %s, got %s", timezone, user.Timezone)
-	}
-
 	if user.CreatedAt.IsZero() {
 		t.Error("CreatedAt should not be zero")
 	}
@@ -37,11 +32,3 @@ func TestNewUser(t *testing.T) {
 		t.Errorf("CreatedAt and UpdatedAt should be nearly identical, diff: %v", diff)
 	}
 }
-
-func TestUser_DefaultTimezone(t *testing.T) {
-	user := NewUser("test@example.com", "hash", "")
-
-	if user.Timezone != "UTC" {
-		t.Errorf("Expected default timezone UTC, got %s", user.Timezone)
-	}
-}

internal/i18n/locales/en.json

@@ -46,7 +46,9 @@
     "invalid_token_or_password": "Invalid or expired token, or password requirements not met",
     "failed_reset_password": "Failed to reset password",
     "failed_delete_user": "Failed to delete user",
-    "failed_get_stats": "Failed to get statistics"
+    "failed_get_stats": "Failed to get statistics",
+    "timezone_required": "Timezone is required",
+    "invalid_timezone": "Invalid timezone (must be a valid IANA timezone)"
   },
   "success": {
     "registration_with_verification": "Registration successful. Please check your email to verify your account.",

internal/i18n/locales/es.json

@@ -46,7 +46,9 @@
     "invalid_token_or_password": "Token inválido o expirado, o no se cumplen los requisitos de contraseña",
     "failed_reset_password": "Error al restablecer contraseña",
     "failed_delete_user": "Error al eliminar usuario",
-    "failed_get_stats": "Error al obtener estadísticas"
+    "failed_get_stats": "Error al obtener estadísticas",
+    "timezone_required": "La zona horaria es requerida",
+    "invalid_timezone": "Zona horaria inválida (debe ser una zona horaria IANA válida)"
   },
   "success": {
     "registration_with_verification": "Registro exitoso. Por favor revisa tu correo electrónico para verificar tu cuenta.",

internal/infrastructure/http/auth_handlers.go

@@ -65,7 +65,6 @@ func NewAuthHandlers(
 type RegisterRequest struct {
 	Email    string `json:"email"`
 	Password string `json:"password"`
-	Timezone string `json:"timezone"`
 }
 
 type LoginRequest struct {
@@ -100,7 +99,7 @@ type LogoutRequest struct {
 // @Produce json
 // @Param request body RegisterRequest true "Registration data (password requires: min 8 chars, uppercase, lowercase, digit, special char)"
 // @Success 201 {object} RegisterResponse "Returns user ID and message about next steps"
-// @Failure 400 {object} ValidationErrorResponse "Invalid input: email format, password requirements, or timezone"
+// @Failure 400 {object} ValidationErrorResponse "Invalid input: email format or password requirements"
 // @Failure 403 {object} ErrorResponse "Registration is closed"
 // @Failure 409 {object} ErrorResponse "Email already registered"
 // @Failure 500 {object} ErrorResponse "Internal server error"
@@ -115,7 +114,6 @@ func (h *AuthHandlers) Register(w http.ResponseWriter, r *http.Request) {
 	cmd := commands.RegisterUserCommand{
 		Email:    req.Email,
 		Password: req.Password,
-		Timezone: req.Timezone,
 	}
 
 	result, err := h.registerHandler.Handle(r.Context(), cmd)

internal/infrastructure/http/habit_handlers.go

@@ -9,7 +9,6 @@ import (
 
 	"apocapoc-api/internal/application/commands"
 	"apocapoc-api/internal/application/queries"
-	"apocapoc-api/internal/domain/repositories"
 	"apocapoc-api/internal/i18n"
 	"apocapoc-api/internal/shared/errors"
 
@@ -26,7 +25,6 @@ type HabitHandlers struct {
 	archiveHandler         *commands.ArchiveHabitHandler
 	markHandler            *commands.MarkHabitHandler
 	unmarkHandler          *commands.UnmarkHabitHandler
-	userRepo               repositories.UserRepository
 	translator             *i18n.Translator
 }
 
@@ -40,7 +38,6 @@ func NewHabitHandlers(
 	archiveHandler *commands.ArchiveHabitHandler,
 	markHandler *commands.MarkHabitHandler,
 	unmarkHandler *commands.UnmarkHabitHandler,
-	userRepo repositories.UserRepository,
 	translator *i18n.Translator,
 ) *HabitHandlers {
 	return &HabitHandlers{
@@ -53,7 +50,6 @@ func NewHabitHandlers(
 		archiveHandler:         archiveHandler,
 		markHandler:            markHandler,
 		unmarkHandler:          unmarkHandler,
-		userRepo:               userRepo,
 		translator:             translator,
 	}
 }
@@ -440,11 +436,13 @@ func (h *HabitHandlers) GetHabitEntries(w http.ResponseWriter, r *http.Request)
 
 // GetTodaysHabits godoc
 // @Summary Get today's habits
-// @Description Get all habits scheduled for today for the authenticated user. Includes the entry for today if it exists.
+// @Description Get all habits scheduled for today for the authenticated user. Includes the entry for today if it exists. Requires timezone as query parameter (e.g., ?timezone=America/New_York).
 // @Tags habits
 // @Produce json
 // @Security BearerAuth
+// @Param timezone query string true "IANA timezone (e.g., 'America/New_York', 'Europe/Madrid', 'UTC')"
 // @Success 200 {array} TodaysHabitResponse
+// @Failure 400 {object} ErrorResponse "Invalid or missing timezone"
 // @Failure 401 {object} ErrorResponse
 // @Failure 500 {object} ErrorResponse
 // @Router /habits/today [get]
@@ -455,15 +453,16 @@ func (h *HabitHandlers) GetTodaysHabits(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
-	user, err := h.userRepo.FindByID(r.Context(), userID)
+	timezone := r.URL.Query().Get("timezone")
-	if err != nil {
+	if timezone == "" {
-		respondErrorI18n(w, r, h.translator, http.StatusInternalServerError, "failed_get_user")
+		respondErrorI18n(w, r, h.translator, http.StatusBadRequest, "timezone_required")
 		return
 	}
 
-	loc, err := time.LoadLocation(user.Timezone)
+	loc, err := time.LoadLocation(timezone)
 	if err != nil {
-		loc = time.UTC
+		respondErrorI18n(w, r, h.translator, http.StatusBadRequest, "invalid_timezone")
+		return
 	}
 
 	today := time.Now().In(loc)
@@ -471,7 +470,7 @@ func (h *HabitHandlers) GetTodaysHabits(w http.ResponseWriter, r *http.Request)
 
 	query := queries.GetTodaysHabitsQuery{
 		UserID:   userID,
-		Timezone: user.Timezone,
+		Timezone: timezone,
 		Date:     todayDate,
 	}
 

internal/infrastructure/http/integration_test.go

@@ -70,7 +70,7 @@ func setupTestServer(t *testing.T) *TestServer {
 	translator, _ := i18n.NewTranslator()
 
 	authHandlers := NewAuthHandlers(registerHandler, loginHandler, refreshTokenHandler, revokeTokenHandler, revokeAllTokensHandler, verifyEmailHandler, resendVerificationEmailHandler, requestPasswordResetHandler, resetPasswordHandler, jwtService, refreshTokenRepo, refreshTokenExpiry, translator)
-	habitHandlers := NewHabitHandlers(createHandler, getTodaysHandler, getUserHabitsHandler, getHabitByIDHandler, getHabitEntriesHandler, updateHandler, archiveHandler, markHandler, unmarkHandler, userRepo, translator)
+	habitHandlers := NewHabitHandlers(createHandler, getTodaysHandler, getUserHabitsHandler, getHabitByIDHandler, getHabitEntriesHandler, updateHandler, archiveHandler, markHandler, unmarkHandler, translator)
 	statsHandlers := NewStatsHandlers(getHabitStatsHandler, translator)
 	healthHandlers := NewHealthHandlers(db)
 	userHandlers := NewUserHandlers(deleteUserHandler, translator)

internal/infrastructure/persistence/sqlite/migrations.go

@@ -25,6 +25,10 @@ func RunMigrations(db *sql.DB) error {
 		return err
 	}
 
+	if err := removeTimezoneColumn(db); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -54,6 +58,23 @@ func addEmailVerificationColumns(db *sql.DB) error {
 	return nil
 }
 
+func removeTimezoneColumn(db *sql.DB) error {
+	exists, err := columnExists(db, "users", "timezone")
+	if err != nil {
+		return err
+	}
+
+	if !exists {
+		return nil
+	}
+
+	if _, err := db.Exec("ALTER TABLE users DROP COLUMN timezone"); err != nil {
+		return fmt.Errorf("failed to drop timezone column: %w", err)
+	}
+
+	return nil
+}
+
 func columnExists(db *sql.DB, table, column string) (bool, error) {
 	query := fmt.Sprintf("SELECT COUNT(*) FROM pragma_table_info('%s') WHERE name = ?", table)
 	var count int
@@ -69,7 +90,6 @@ CREATE TABLE IF NOT EXISTS users (
 	id TEXT PRIMARY KEY,
 	email TEXT UNIQUE NOT NULL,
 	password_hash TEXT NOT NULL,
-	timezone TEXT DEFAULT 'UTC',
 	created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
 	updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
 );

internal/infrastructure/persistence/sqlite/user_repository.go

@@ -24,15 +24,14 @@ func (r *UserRepository) Create(ctx context.Context, user *entities.User) error
 	user.ID = uuid.New().String()
 
 	query := `
-		INSERT INTO users (id, email, password_hash, timezone, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at)
+		INSERT INTO users (id, email, password_hash, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at)
-		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?)
 	`
 
 	_, err := r.db.ExecContext(ctx, query,
 		user.ID,
 		user.Email,
 		user.PasswordHash,
-		user.Timezone,
 		user.EmailVerified,
 		user.EmailVerificationToken,
 		user.EmailVerificationExpiry,
@@ -52,7 +51,7 @@ func (r *UserRepository) Create(ctx context.Context, user *entities.User) error
 
 func (r *UserRepository) FindByID(ctx context.Context, id string) (*entities.User, error) {
 	query := `
-		SELECT id, email, password_hash, timezone, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at
+		SELECT id, email, password_hash, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at
 		FROM users
 		WHERE id = ?
 	`
@@ -62,7 +61,6 @@ func (r *UserRepository) FindByID(ctx context.Context, id string) (*entities.Use
 		&user.ID,
 		&user.Email,
 		&user.PasswordHash,
-		&user.Timezone,
 		&user.EmailVerified,
 		&user.EmailVerificationToken,
 		&user.EmailVerificationExpiry,
@@ -82,7 +80,7 @@ func (r *UserRepository) FindByID(ctx context.Context, id string) (*entities.Use
 
 func (r *UserRepository) FindByEmail(ctx context.Context, email string) (*entities.User, error) {
 	query := `
-		SELECT id, email, password_hash, timezone, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at
+		SELECT id, email, password_hash, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at
 		FROM users
 		WHERE email = ?
 	`
@@ -92,7 +90,6 @@ func (r *UserRepository) FindByEmail(ctx context.Context, email string) (*entiti
 		&user.ID,
 		&user.Email,
 		&user.PasswordHash,
-		&user.Timezone,
 		&user.EmailVerified,
 		&user.EmailVerificationToken,
 		&user.EmailVerificationExpiry,
@@ -112,7 +109,7 @@ func (r *UserRepository) FindByEmail(ctx context.Context, email string) (*entiti
 
 func (r *UserRepository) FindByVerificationToken(ctx context.Context, token string) (*entities.User, error) {
 	query := `
-		SELECT id, email, password_hash, timezone, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at
+		SELECT id, email, password_hash, email_verified, email_verification_token, email_verification_expiry, created_at, updated_at
 		FROM users
 		WHERE email_verification_token = ?
 	`
@@ -122,7 +119,6 @@ func (r *UserRepository) FindByVerificationToken(ctx context.Context, token stri
 		&user.ID,
 		&user.Email,
 		&user.PasswordHash,
-		&user.Timezone,
 		&user.EmailVerified,
 		&user.EmailVerificationToken,
 		&user.EmailVerificationExpiry,
@@ -143,14 +139,13 @@ func (r *UserRepository) FindByVerificationToken(ctx context.Context, token stri
 func (r *UserRepository) Update(ctx context.Context, user *entities.User) error {
 	query := `
 		UPDATE users
-		SET email = ?, password_hash = ?, timezone = ?, email_verified = ?, email_verification_token = ?, email_verification_expiry = ?, updated_at = ?
+		SET email = ?, password_hash = ?, email_verified = ?, email_verification_token = ?, email_verification_expiry = ?, updated_at = ?
 		WHERE id = ?
 	`
 
 	result, err := r.db.ExecContext(ctx, query,
 		user.Email,
 		user.PasswordHash,
-		user.Timezone,
 		user.EmailVerified,
 		user.EmailVerificationToken,
 		user.EmailVerificationExpiry,

internal/infrastructure/persistence/sqlite/user_repository_test.go

@@ -35,7 +35,6 @@ func TestUserRepositoryCreate(t *testing.T) {
 	user := &entities.User{
 		Email:        "test@example.com",
 		PasswordHash: "hashed_password",
-		Timezone:     "UTC",
 		CreatedAt:    time.Now(),
 		UpdatedAt:    time.Now(),
 	}
@@ -60,7 +59,6 @@ func TestUserRepositoryCreateDuplicateEmail(t *testing.T) {
 	user1 := &entities.User{
 		Email:        "duplicate@example.com",
 		PasswordHash: "hash1",
-		Timezone:     "UTC",
 		CreatedAt:    time.Now(),
 		UpdatedAt:    time.Now(),
 	}
@@ -73,7 +71,6 @@ func TestUserRepositoryCreateDuplicateEmail(t *testing.T) {
 	user2 := &entities.User{
 		Email:        "duplicate@example.com",
 		PasswordHash: "hash2",
-		Timezone:     "UTC",
 		CreatedAt:    time.Now(),
 		UpdatedAt:    time.Now(),
 	}
@@ -94,7 +91,6 @@ func TestUserRepositoryFindByID(t *testing.T) {
 	user := &entities.User{
 		Email:        "find@example.com",
 		PasswordHash: "hashed",
-		Timezone:     "America/New_York",
 		CreatedAt:    time.Now(),
 		UpdatedAt:    time.Now(),
 	}
@@ -115,8 +111,6 @@ func TestUserRepositoryFindByID(t *testing.T) {
 	if found.Email != user.Email {
 		t.Errorf("Expected email %s, got %s", user.Email, found.Email)
 	}
-	if found.Timezone != user.Timezone {
-		t.Errorf("Expected timezone %s, got %s", user.Timezone, found.Timezone)
 	}
 }
 
@@ -143,7 +137,6 @@ func TestUserRepositoryFindByEmail(t *testing.T) {
 	user := &entities.User{
 		Email:        "email@test.com",
 		PasswordHash: "hashed",
-		Timezone:     "UTC",
 		CreatedAt:    time.Now(),
 		UpdatedAt:    time.Now(),
 	}
@@ -189,7 +182,6 @@ func TestUserRepositoryUpdate(t *testing.T) {
 	user := &entities.User{
 		Email:        "original@example.com",
 		PasswordHash: "hash1",
-		Timezone:     "UTC",
 		CreatedAt:    time.Now(),
 		UpdatedAt:    time.Now(),
 	}
@@ -200,7 +192,6 @@ func TestUserRepositoryUpdate(t *testing.T) {
 	}
 
 	user.Email = "updated@example.com"
-	user.Timezone = "Europe/Madrid"
 	user.UpdatedAt = time.Now()
 
 	err = repo.Update(ctx, user)
@@ -216,8 +207,6 @@ func TestUserRepositoryUpdate(t *testing.T) {
 	if found.Email != "updated@example.com" {
 		t.Errorf("Expected email updated@example.com, got %s", found.Email)
 	}
-	if found.Timezone != "Europe/Madrid" {
-		t.Errorf("Expected timezone Europe/Madrid, got %s", found.Timezone)
 	}
 }
 
@@ -232,7 +221,6 @@ func TestUserRepositoryUpdateNotFound(t *testing.T) {
 		ID:           "non-existent",
 		Email:        "test@example.com",
 		PasswordHash: "hash",
-		Timezone:     "UTC",
 		CreatedAt:    time.Now(),
 		UpdatedAt:    time.Now(),
 	}

internal/shared/validation/validator.go

@@ -114,7 +114,7 @@ func ValidateTimezone(timezone string) error {
 	return nil
 }
 
-func ValidateRegistration(email, password, timezone string) error {
+func ValidateRegistration(email, password string) error {
 	if err := ValidateEmail(email); err != nil {
 		return err
 	}
@@ -123,9 +123,5 @@ func ValidateRegistration(email, password, timezone string) error {
 		return err
 	}
 
-	if err := ValidateTimezone(timezone); err != nil {
-		return err
-	}
-
 	return nil
 }