fix: repair user password reset and recreate flow

internal/service/auth.go

@@ -95,6 +95,9 @@ func (s *AuthService) Register(ctx context.Context, username, password string) (
 	} else if existing != nil {
 		return nil, nil, ErrUsernameTaken
 	}
+	if err := s.repo.User.ReleaseDeletedUsername(ctx, username); err != nil {
+		return nil, nil, err
+	}
 	if n, err := s.repo.User.Count(ctx); err != nil {
 		return nil, nil, err
 	} else if n >= LicensedMaxUsers(ctx, s.repo) {
@@ -181,6 +184,29 @@ func (s *AuthService) ChangePassword(ctx context.Context, userID, oldPwd, newPwd
 	return s.repo.User.UpdatePassword(ctx, userID, hash)
 }
 
+// ResetPassword lets an administrator set a new password without knowing the
+// user's old password.
+func (s *AuthService) ResetPassword(ctx context.Context, userID, newPwd string) error {
+	if strings.TrimSpace(userID) == "" {
+		return errors.New("missing user id")
+	}
+	if strings.TrimSpace(newPwd) == "" || len(newPwd) < 6 {
+		return errors.New("new password must be at least 6 characters")
+	}
+	u, err := s.repo.User.FindByID(ctx, userID)
+	if err != nil {
+		return err
+	}
+	if u == nil {
+		return errors.New("user not found")
+	}
+	hash, err := hashPassword(newPwd)
+	if err != nil {
+		return err
+	}
+	return s.repo.User.UpdatePassword(ctx, userID, hash)
+}
+
 // VerifyPassword checks a user's current password without mutating account
 // state. It is used for sensitive self-service actions such as hiding adult
 // libraries or deleting play profiles.

internal/service/auth_user_limits_test.go

@@ -21,7 +21,7 @@ func newAuthTestServices(t *testing.T) (*repository.Container, *AuthService, *Pr
 	if err != nil {
 		t.Fatal(err)
 	}
-	if err := db.AutoMigrate(&model.User{}, &model.UserPermission{}, &model.RefreshToken{}); err != nil {
+	if err := db.AutoMigrate(&model.User{}, &model.UserPermission{}, &model.RefreshToken{}, &model.TelegramBinding{}); err != nil {
 		t.Fatal(err)
 	}
 	repos := repository.New(db)
@@ -66,6 +66,87 @@ func TestRegisterDefaultsAdultLibrariesHidden(t *testing.T) {
 	}
 }
 
+func TestDeletedUserCanBeRecreatedWithSameUsername(t *testing.T) {
+	ctx := context.Background()
+	repos, auth, _, _ := newAuthTestServices(t)
+	user, _, err := auth.Register(ctx, "viewer", "old-password")
+	if err != nil {
+		t.Fatalf("register old user: %v", err)
+	}
+	if err := repos.DB.Create(&model.TelegramBinding{
+		TelegramUserID: 10001,
+		TelegramName:   "@viewer",
+		ChatID:         10001,
+		UserID:         user.ID,
+	}).Error; err != nil {
+		t.Fatalf("create telegram binding: %v", err)
+	}
+	if err := repos.User.Delete(ctx, user.ID); err != nil {
+		t.Fatalf("delete user: %v", err)
+	}
+
+	next, _, err := auth.Register(ctx, "viewer", "new-password")
+	if err != nil {
+		t.Fatalf("register same username after delete: %v", err)
+	}
+	if next.ID == user.ID {
+		t.Fatal("recreated user should be a new account row")
+	}
+	if _, err := auth.Login(ctx, "viewer", "new-password"); err != nil {
+		t.Fatalf("login recreated user: %v", err)
+	}
+	var bindings int64
+	if err := repos.DB.Model(&model.TelegramBinding{}).Where("telegram_user_id = ?", 10001).Count(&bindings).Error; err != nil {
+		t.Fatalf("count bindings: %v", err)
+	}
+	if bindings != 0 {
+		t.Fatalf("deleted user telegram bindings should be removed, got %d", bindings)
+	}
+}
+
+func TestRegisterReleasesLegacySoftDeletedUsername(t *testing.T) {
+	ctx := context.Background()
+	repos, auth, _, _ := newAuthTestServices(t)
+	if err := repos.User.Create(ctx, &model.User{
+		Username:     "legacy",
+		PasswordHash: "hash",
+		Role:         "user",
+		Tier:         "free",
+	}); err != nil {
+		t.Fatal(err)
+	}
+	legacy, err := repos.User.FindByUsername(ctx, "legacy")
+	if err != nil || legacy == nil {
+		t.Fatalf("find legacy user: %v", err)
+	}
+	if err := repos.DB.Delete(&model.User{}, "id = ?", legacy.ID).Error; err != nil {
+		t.Fatalf("legacy soft delete: %v", err)
+	}
+
+	if _, _, err := auth.Register(ctx, "legacy", "new-password"); err != nil {
+		t.Fatalf("register should release old soft-deleted username: %v", err)
+	}
+}
+
+func TestAdminResetPasswordAllowsLoginWithNewPassword(t *testing.T) {
+	ctx := context.Background()
+	_, auth, _, _ := newAuthTestServices(t)
+	user, _, err := auth.Register(ctx, "viewer", "old-password")
+	if err != nil {
+		t.Fatalf("register: %v", err)
+	}
+
+	if err := auth.ResetPassword(ctx, user.ID, "new-password"); err != nil {
+		t.Fatalf("reset password: %v", err)
+	}
+	if _, err := auth.Login(ctx, "viewer", "old-password"); !errors.Is(err, ErrInvalidCredentials) {
+		t.Fatalf("old password should fail, got %v", err)
+	}
+	if _, err := auth.Login(ctx, "viewer", "new-password"); err != nil {
+		t.Fatalf("new password should login: %v", err)
+	}
+}
+
 func TestDefaultPermissionsAreViewerOnly(t *testing.T) {
 	perms := DefaultPermissions("user-1")
 	if !perms.CanViewDashboard || !perms.CanPlayMedia || !perms.CanExternalPlayer {

internal/service/telegram_bot.go

@@ -231,14 +231,18 @@ func (s *TelegramBotService) cmdStart(ctx context.Context, msg *TelegramMessage,
 	if len(args) == 0 {
 		if binding := s.telegramBinding(ctx, msg.From.ID); binding != nil {
 			user, _ := s.repo.User.FindByID(ctx, binding.UserID)
+			if user == nil {
+				_ = s.repo.DB.WithContext(ctx).Unscoped().Delete(&model.TelegramBinding{}, "id = ?", binding.ID).Error
+				return telegramCommandReply{Text: "之前绑定的媒体中心账号已不存在，请重新绑定：\n<code>/start 用户名 密码</code>"}
+			}
 			status := "未隐藏"
-			if user != nil && user.HideAdult {
+			if user.HideAdult {
 				status = "已隐藏"
 			}
 			return telegramCommandReply{
 				Text: fmt.Sprintf("<b>MediaStationGo 已绑定</b>\n\n你好 %s，当前账号：<b>%s</b>\n成人目录：<b>%s</b>", name, userNameOrFallback(user), status),
 				Buttons: [][]telegramInlineButton{{{
-					Text: map[bool]string{true: "显示成人目录", false: "隐藏成人目录"}[user != nil && user.HideAdult],
+					Text: map[bool]string{true: "显示成人目录", false: "隐藏成人目录"}[user.HideAdult],
 					Data: "adult_toggle",
 				}}},
 			}
@@ -895,6 +899,9 @@ func (s *TelegramBotService) upsertTelegramBinding(ctx context.Context, msg *Tel
 	if err != nil && err != gorm.ErrRecordNotFound {
 		return err
 	}
+	if err := s.repo.DB.WithContext(ctx).Unscoped().Where("telegram_user_id = ?", int64(msg.From.ID)).Delete(&model.TelegramBinding{}).Error; err != nil {
+		return err
+	}
 	return s.repo.DB.WithContext(ctx).Create(&model.TelegramBinding{
 		TelegramUserID: int64(msg.From.ID),
 		TelegramName:   name,

internal/service/telegram_bot_user_test.go

@@ -0,0 +1,39 @@
+package service
+
+import (
+	"strings"
+	"testing"
+
+	"go.uber.org/zap"
+
+	"github.com/ShukeBta/MediaStationGo/internal/model"
+)
+
+func TestTelegramStartClearsStaleUserBinding(t *testing.T) {
+	repos, _, _, _ := newAuthTestServices(t)
+	if err := repos.DB.Create(&model.TelegramBinding{
+		TelegramUserID: 20001,
+		TelegramName:   "@viewer",
+		ChatID:         20001,
+		UserID:         "deleted-user",
+	}).Error; err != nil {
+		t.Fatalf("create binding: %v", err)
+	}
+	bot := NewTelegramBotService(zap.NewNop(), repos, nil)
+
+	reply := bot.cmdStart(t.Context(), &TelegramMessage{
+		From: TelegramUser{ID: 20001, Username: "viewer", FirstName: "Viewer"},
+		Chat: TelegramChat{ID: 20001, Type: "private"},
+	}, nil)
+
+	if !strings.Contains(reply.Text, "已不存在") {
+		t.Fatalf("expected stale binding message, got %q", reply.Text)
+	}
+	var count int64
+	if err := repos.DB.Model(&model.TelegramBinding{}).Where("telegram_user_id = ?", 20001).Count(&count).Error; err != nil {
+		t.Fatalf("count binding: %v", err)
+	}
+	if count != 0 {
+		t.Fatalf("stale binding should be removed, got %d", count)
+	}
+}