merge: 合并 upstream/main

backend/internal/service/concurrency_service.go

@@ -18,6 +18,11 @@ type ConcurrencyCache interface {
 	ReleaseAccountSlot(ctx context.Context, accountID int64, requestID string) error
 	GetAccountConcurrency(ctx context.Context, accountID int64) (int, error)
 
+	// 账号等待队列（账号级）
+	IncrementAccountWaitCount(ctx context.Context, accountID int64, maxWait int) (bool, error)
+	DecrementAccountWaitCount(ctx context.Context, accountID int64) error
+	GetAccountWaitingCount(ctx context.Context, accountID int64) (int, error)
+
 	// 用户槽位管理
 	// 键格式: concurrency:user:{userID}（有序集合，成员为 requestID）
 	AcquireUserSlot(ctx context.Context, userID int64, maxConcurrency int, requestID string) (bool, error)
@@ -27,6 +32,12 @@ type ConcurrencyCache interface {
 	// 等待队列计数（只在首次创建时设置 TTL）
 	IncrementWaitCount(ctx context.Context, userID int64, maxWait int) (bool, error)
 	DecrementWaitCount(ctx context.Context, userID int64) error
+
+	// 批量负载查询（只读）
+	GetAccountsLoadBatch(ctx context.Context, accounts []AccountWithConcurrency) (map[int64]*AccountLoadInfo, error)
+
+	// 清理过期槽位（后台任务）
+	CleanupExpiredAccountSlots(ctx context.Context, accountID int64) error
 }
 
 // generateRequestID generates a unique request ID for concurrency slot tracking
@@ -61,6 +72,18 @@ type AcquireResult struct {
 	ReleaseFunc func() // Must be called when done (typically via defer)
 }
 
+type AccountWithConcurrency struct {
+	ID             int64
+	MaxConcurrency int
+}
+
+type AccountLoadInfo struct {
+	AccountID          int64
+	CurrentConcurrency int
+	WaitingCount       int
+	LoadRate           int // 0-100+ (percent)
+}
+
 // AcquireAccountSlot attempts to acquire a concurrency slot for an account.
 // If the account is at max concurrency, it waits until a slot is available or timeout.
 // Returns a release function that MUST be called when the request completes.
@@ -177,6 +200,42 @@ func (s *ConcurrencyService) DecrementWaitCount(ctx context.Context, userID int6
 	}
 }
 
+// IncrementAccountWaitCount increments the wait queue counter for an account.
+func (s *ConcurrencyService) IncrementAccountWaitCount(ctx context.Context, accountID int64, maxWait int) (bool, error) {
+	if s.cache == nil {
+		return true, nil
+	}
+
+	result, err := s.cache.IncrementAccountWaitCount(ctx, accountID, maxWait)
+	if err != nil {
+		log.Printf("Warning: increment wait count failed for account %d: %v", accountID, err)
+		return true, nil
+	}
+	return result, nil
+}
+
+// DecrementAccountWaitCount decrements the wait queue counter for an account.
+func (s *ConcurrencyService) DecrementAccountWaitCount(ctx context.Context, accountID int64) {
+	if s.cache == nil {
+		return
+	}
+
+	bgCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := s.cache.DecrementAccountWaitCount(bgCtx, accountID); err != nil {
+		log.Printf("Warning: decrement wait count failed for account %d: %v", accountID, err)
+	}
+}
+
+// GetAccountWaitingCount gets current wait queue count for an account.
+func (s *ConcurrencyService) GetAccountWaitingCount(ctx context.Context, accountID int64) (int, error) {
+	if s.cache == nil {
+		return 0, nil
+	}
+	return s.cache.GetAccountWaitingCount(ctx, accountID)
+}
+
 // CalculateMaxWait calculates the maximum wait queue size for a user
 // maxWait = userConcurrency + defaultExtraWaitSlots
 func CalculateMaxWait(userConcurrency int) int {
@@ -186,6 +245,57 @@ func CalculateMaxWait(userConcurrency int) int {
 	return userConcurrency + defaultExtraWaitSlots
 }
 
+// GetAccountsLoadBatch returns load info for multiple accounts.
+func (s *ConcurrencyService) GetAccountsLoadBatch(ctx context.Context, accounts []AccountWithConcurrency) (map[int64]*AccountLoadInfo, error) {
+	if s.cache == nil {
+		return map[int64]*AccountLoadInfo{}, nil
+	}
+	return s.cache.GetAccountsLoadBatch(ctx, accounts)
+}
+
+// CleanupExpiredAccountSlots removes expired slots for one account (background task).
+func (s *ConcurrencyService) CleanupExpiredAccountSlots(ctx context.Context, accountID int64) error {
+	if s.cache == nil {
+		return nil
+	}
+	return s.cache.CleanupExpiredAccountSlots(ctx, accountID)
+}
+
+// StartSlotCleanupWorker starts a background cleanup worker for expired account slots.
+func (s *ConcurrencyService) StartSlotCleanupWorker(accountRepo AccountRepository, interval time.Duration) {
+	if s == nil || s.cache == nil || accountRepo == nil || interval <= 0 {
+		return
+	}
+
+	runCleanup := func() {
+		listCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		accounts, err := accountRepo.ListSchedulable(listCtx)
+		cancel()
+		if err != nil {
+			log.Printf("Warning: list schedulable accounts failed: %v", err)
+			return
+		}
+		for _, account := range accounts {
+			accountCtx, accountCancel := context.WithTimeout(context.Background(), 2*time.Second)
+			err := s.cache.CleanupExpiredAccountSlots(accountCtx, account.ID)
+			accountCancel()
+			if err != nil {
+				log.Printf("Warning: cleanup expired slots failed for account %d: %v", account.ID, err)
+			}
+		}
+	}
+
+	go func() {
+		ticker := time.NewTicker(interval)
+		defer ticker.Stop()
+
+		runCleanup()
+		for range ticker.C {
+			runCleanup()
+		}
+	}()
+}
+
 // GetAccountConcurrencyBatch gets current concurrency counts for multiple accounts
 // Returns a map of accountID -> current concurrency count
 func (s *ConcurrencyService) GetAccountConcurrencyBatch(ctx context.Context, accountIDs []int64) (map[int64]int, error) {

backend/internal/service/domain_constants.go

@@ -91,6 +91,9 @@ const (
 
 	// 管理员 API Key
 	SettingKeyAdminApiKey = "admin_api_key" // 全局管理员 API Key（用于外部系统集成）
+
+	// Gemini 配额策略（JSON）
+	SettingKeyGeminiQuotaPolicy = "gemini_quota_policy"
 )
 
 // Admin API Key prefix (distinct from user "sk-" keys)

backend/internal/service/gateway_multiplatform_test.go

@@ -32,6 +32,16 @@ func (m *mockAccountRepoForPlatform) GetByID(ctx context.Context, id int64) (*Ac
 	return nil, errors.New("account not found")
 }
 
+func (m *mockAccountRepoForPlatform) GetByIDs(ctx context.Context, ids []int64) ([]*Account, error) {
+	var result []*Account
+	for _, id := range ids {
+		if acc, ok := m.accountsByID[id]; ok {
+			result = append(result, acc)
+		}
+	}
+	return result, nil
+}
+
 func (m *mockAccountRepoForPlatform) ExistsByID(ctx context.Context, id int64) (bool, error) {
 	if m.accountsByID == nil {
 		return false, nil
@@ -261,6 +271,34 @@ func TestGatewayService_SelectAccountForModelWithPlatform_PriorityAndLastUsed(t
 	require.Equal(t, int64(2), acc.ID, "同优先级应选择最久未用的账户")
 }
 
+func TestGatewayService_SelectAccountForModelWithPlatform_GeminiOAuthPreference(t *testing.T) {
+	ctx := context.Background()
+
+	repo := &mockAccountRepoForPlatform{
+		accounts: []Account{
+			{ID: 1, Platform: PlatformGemini, Priority: 1, Status: StatusActive, Schedulable: true, Type: AccountTypeApiKey},
+			{ID: 2, Platform: PlatformGemini, Priority: 1, Status: StatusActive, Schedulable: true, Type: AccountTypeOAuth},
+		},
+		accountsByID: map[int64]*Account{},
+	}
+	for i := range repo.accounts {
+		repo.accountsByID[repo.accounts[i].ID] = &repo.accounts[i]
+	}
+
+	cache := &mockGatewayCacheForPlatform{}
+
+	svc := &GatewayService{
+		accountRepo: repo,
+		cache:       cache,
+		cfg:         testConfig(),
+	}
+
+	acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "", "gemini-2.5-pro", nil, PlatformGemini)
+	require.NoError(t, err)
+	require.NotNil(t, acc)
+	require.Equal(t, int64(2), acc.ID, "同优先级且未使用时应优先选择OAuth账户")
+}
+
 // TestGatewayService_SelectAccountForModelWithPlatform_NoAvailableAccounts 测试无可用账户
 func TestGatewayService_SelectAccountForModelWithPlatform_NoAvailableAccounts(t *testing.T) {
 	ctx := context.Background()
@@ -576,6 +614,32 @@ func TestGatewayService_isModelSupportedByAccount(t *testing.T) {
 func TestGatewayService_selectAccountWithMixedScheduling(t *testing.T) {
 	ctx := context.Background()
 
+	t.Run("混合调度-Gemini优先选择OAuth账户", func(t *testing.T) {
+		repo := &mockAccountRepoForPlatform{
+			accounts: []Account{
+				{ID: 1, Platform: PlatformGemini, Priority: 1, Status: StatusActive, Schedulable: true, Type: AccountTypeApiKey},
+				{ID: 2, Platform: PlatformGemini, Priority: 1, Status: StatusActive, Schedulable: true, Type: AccountTypeOAuth},
+			},
+			accountsByID: map[int64]*Account{},
+		}
+		for i := range repo.accounts {
+			repo.accountsByID[repo.accounts[i].ID] = &repo.accounts[i]
+		}
+
+		cache := &mockGatewayCacheForPlatform{}
+
+		svc := &GatewayService{
+			accountRepo: repo,
+			cache:       cache,
+			cfg:         testConfig(),
+		}
+
+		acc, err := svc.selectAccountWithMixedScheduling(ctx, nil, "", "gemini-2.5-pro", nil, PlatformGemini)
+		require.NoError(t, err)
+		require.NotNil(t, acc)
+		require.Equal(t, int64(2), acc.ID, "同优先级且未使用时应优先选择OAuth账户")
+	})
+
 	t.Run("混合调度-包含启用mixed_scheduling的antigravity账户", func(t *testing.T) {
 		repo := &mockAccountRepoForPlatform{
 			accounts: []Account{
@@ -783,3 +847,160 @@ func TestAccount_IsMixedSchedulingEnabled(t *testing.T) {
 		})
 	}
 }
+
+// mockConcurrencyService for testing
+type mockConcurrencyService struct {
+	accountLoads      map[int64]*AccountLoadInfo
+	accountWaitCounts map[int64]int
+	acquireResults    map[int64]bool
+}
+
+func (m *mockConcurrencyService) GetAccountsLoadBatch(ctx context.Context, accounts []AccountWithConcurrency) (map[int64]*AccountLoadInfo, error) {
+	if m.accountLoads == nil {
+		return map[int64]*AccountLoadInfo{}, nil
+	}
+	result := make(map[int64]*AccountLoadInfo)
+	for _, acc := range accounts {
+		if load, ok := m.accountLoads[acc.ID]; ok {
+			result[acc.ID] = load
+		} else {
+			result[acc.ID] = &AccountLoadInfo{
+				AccountID:          acc.ID,
+				CurrentConcurrency: 0,
+				WaitingCount:       0,
+				LoadRate:           0,
+			}
+		}
+	}
+	return result, nil
+}
+
+func (m *mockConcurrencyService) GetAccountWaitingCount(ctx context.Context, accountID int64) (int, error) {
+	if m.accountWaitCounts == nil {
+		return 0, nil
+	}
+	return m.accountWaitCounts[accountID], nil
+}
+
+// TestGatewayService_SelectAccountWithLoadAwareness tests load-aware account selection
+func TestGatewayService_SelectAccountWithLoadAwareness(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("禁用负载批量查询-降级到传统选择", func(t *testing.T) {
+		repo := &mockAccountRepoForPlatform{
+			accounts: []Account{
+				{ID: 1, Platform: PlatformAnthropic, Priority: 1, Status: StatusActive, Schedulable: true, Concurrency: 5},
+				{ID: 2, Platform: PlatformAnthropic, Priority: 2, Status: StatusActive, Schedulable: true, Concurrency: 5},
+			},
+			accountsByID: map[int64]*Account{},
+		}
+		for i := range repo.accounts {
+			repo.accountsByID[repo.accounts[i].ID] = &repo.accounts[i]
+		}
+
+		cache := &mockGatewayCacheForPlatform{}
+
+		cfg := testConfig()
+		cfg.Gateway.Scheduling.LoadBatchEnabled = false
+
+		svc := &GatewayService{
+			accountRepo:        repo,
+			cache:              cache,
+			cfg:                cfg,
+			concurrencyService: nil, // No concurrency service
+		}
+
+		result, err := svc.SelectAccountWithLoadAwareness(ctx, nil, "", "claude-3-5-sonnet-20241022", nil)
+		require.NoError(t, err)
+		require.NotNil(t, result)
+		require.NotNil(t, result.Account)
+		require.Equal(t, int64(1), result.Account.ID, "应选择优先级最高的账号")
+	})
+
+	t.Run("无ConcurrencyService-降级到传统选择", func(t *testing.T) {
+		repo := &mockAccountRepoForPlatform{
+			accounts: []Account{
+				{ID: 1, Platform: PlatformAnthropic, Priority: 2, Status: StatusActive, Schedulable: true, Concurrency: 5},
+				{ID: 2, Platform: PlatformAnthropic, Priority: 1, Status: StatusActive, Schedulable: true, Concurrency: 5},
+			},
+			accountsByID: map[int64]*Account{},
+		}
+		for i := range repo.accounts {
+			repo.accountsByID[repo.accounts[i].ID] = &repo.accounts[i]
+		}
+
+		cache := &mockGatewayCacheForPlatform{}
+
+		cfg := testConfig()
+		cfg.Gateway.Scheduling.LoadBatchEnabled = true
+
+		svc := &GatewayService{
+			accountRepo:        repo,
+			cache:              cache,
+			cfg:                cfg,
+			concurrencyService: nil,
+		}
+
+		result, err := svc.SelectAccountWithLoadAwareness(ctx, nil, "", "claude-3-5-sonnet-20241022", nil)
+		require.NoError(t, err)
+		require.NotNil(t, result)
+		require.NotNil(t, result.Account)
+		require.Equal(t, int64(2), result.Account.ID, "应选择优先级最高的账号")
+	})
+
+	t.Run("排除账号-不选择被排除的账号", func(t *testing.T) {
+		repo := &mockAccountRepoForPlatform{
+			accounts: []Account{
+				{ID: 1, Platform: PlatformAnthropic, Priority: 1, Status: StatusActive, Schedulable: true, Concurrency: 5},
+				{ID: 2, Platform: PlatformAnthropic, Priority: 2, Status: StatusActive, Schedulable: true, Concurrency: 5},
+			},
+			accountsByID: map[int64]*Account{},
+		}
+		for i := range repo.accounts {
+			repo.accountsByID[repo.accounts[i].ID] = &repo.accounts[i]
+		}
+
+		cache := &mockGatewayCacheForPlatform{}
+
+		cfg := testConfig()
+		cfg.Gateway.Scheduling.LoadBatchEnabled = false
+
+		svc := &GatewayService{
+			accountRepo:        repo,
+			cache:              cache,
+			cfg:                cfg,
+			concurrencyService: nil,
+		}
+
+		excludedIDs := map[int64]struct{}{1: {}}
+		result, err := svc.SelectAccountWithLoadAwareness(ctx, nil, "", "claude-3-5-sonnet-20241022", excludedIDs)
+		require.NoError(t, err)
+		require.NotNil(t, result)
+		require.NotNil(t, result.Account)
+		require.Equal(t, int64(2), result.Account.ID, "不应选择被排除的账号")
+	})
+
+	t.Run("无可用账号-返回错误", func(t *testing.T) {
+		repo := &mockAccountRepoForPlatform{
+			accounts:     []Account{},
+			accountsByID: map[int64]*Account{},
+		}
+
+		cache := &mockGatewayCacheForPlatform{}
+
+		cfg := testConfig()
+		cfg.Gateway.Scheduling.LoadBatchEnabled = false
+
+		svc := &GatewayService{
+			accountRepo:        repo,
+			cache:              cache,
+			cfg:                cfg,
+			concurrencyService: nil,
+		}
+
+		result, err := svc.SelectAccountWithLoadAwareness(ctx, nil, "", "claude-3-5-sonnet-20241022", nil)
+		require.Error(t, err)
+		require.Nil(t, result)
+		require.Contains(t, err.Error(), "no available accounts")
+	})
+}

backend/internal/service/gateway_service.go

@@ -13,12 +13,14 @@ import (
 	"log"
 	"net/http"
 	"regexp"
+	"sort"
 	"strings"
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/claude"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
+	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
 
 	"github.com/gin-gonic/gin"
@@ -66,6 +68,20 @@ type GatewayCache interface {
 	RefreshSessionTTL(ctx context.Context, sessionHash string, ttl time.Duration) error
 }
 
+type AccountWaitPlan struct {
+	AccountID      int64
+	MaxConcurrency int
+	Timeout        time.Duration
+	MaxWaiting     int
+}
+
+type AccountSelectionResult struct {
+	Account     *Account
+	Acquired    bool
+	ReleaseFunc func()
+	WaitPlan    *AccountWaitPlan // nil means no wait allowed
+}
+
 // ClaudeUsage 表示Claude API返回的usage信息
 type ClaudeUsage struct {
 	InputTokens              int `json:"input_tokens"`
@@ -108,6 +124,7 @@ type GatewayService struct {
 	identityService     *IdentityService
 	httpUpstream        HTTPUpstream
 	deferredService     *DeferredService
+	concurrencyService  *ConcurrencyService
 }
 
 // NewGatewayService creates a new GatewayService
@@ -119,6 +136,7 @@ func NewGatewayService(
 	userSubRepo UserSubscriptionRepository,
 	cache GatewayCache,
 	cfg *config.Config,
+	concurrencyService *ConcurrencyService,
 	billingService *BillingService,
 	rateLimitService *RateLimitService,
 	billingCacheService *BillingCacheService,
@@ -134,6 +152,7 @@ func NewGatewayService(
 		userSubRepo:         userSubRepo,
 		cache:               cache,
 		cfg:                 cfg,
+		concurrencyService:  concurrencyService,
 		billingService:      billingService,
 		rateLimitService:    rateLimitService,
 		billingCacheService: billingCacheService,
@@ -183,6 +202,14 @@ func (s *GatewayService) GenerateSessionHash(parsed *ParsedRequest) string {
 	return ""
 }
 
+// BindStickySession sets session -> account binding with standard TTL.
+func (s *GatewayService) BindStickySession(ctx context.Context, sessionHash string, accountID int64) error {
+	if sessionHash == "" || accountID <= 0 {
+		return nil
+	}
+	return s.cache.SetSessionAccountID(ctx, sessionHash, accountID, stickySessionTTL)
+}
+
 func (s *GatewayService) extractCacheableContent(parsed *ParsedRequest) string {
 	if parsed == nil {
 		return ""
@@ -332,8 +359,354 @@ func (s *GatewayService) SelectAccountForModelWithExclusions(ctx context.Context
 	return s.selectAccountForModelWithPlatform(ctx, groupID, sessionHash, requestedModel, excludedIDs, platform)
 }
 
+// SelectAccountWithLoadAwareness selects account with load-awareness and wait plan.
+func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}) (*AccountSelectionResult, error) {
+	cfg := s.schedulingConfig()
+	var stickyAccountID int64
+	if sessionHash != "" && s.cache != nil {
+		if accountID, err := s.cache.GetSessionAccountID(ctx, sessionHash); err == nil {
+			stickyAccountID = accountID
+		}
+	}
+	if s.concurrencyService == nil || !cfg.LoadBatchEnabled {
+		account, err := s.SelectAccountForModelWithExclusions(ctx, groupID, sessionHash, requestedModel, excludedIDs)
+		if err != nil {
+			return nil, err
+		}
+		result, err := s.tryAcquireAccountSlot(ctx, account.ID, account.Concurrency)
+		if err == nil && result.Acquired {
+			return &AccountSelectionResult{
+				Account:     account,
+				Acquired:    true,
+				ReleaseFunc: result.ReleaseFunc,
+			}, nil
+		}
+		if stickyAccountID > 0 && stickyAccountID == account.ID && s.concurrencyService != nil {
+			waitingCount, _ := s.concurrencyService.GetAccountWaitingCount(ctx, account.ID)
+			if waitingCount < cfg.StickySessionMaxWaiting {
+				return &AccountSelectionResult{
+					Account: account,
+					WaitPlan: &AccountWaitPlan{
+						AccountID:      account.ID,
+						MaxConcurrency: account.Concurrency,
+						Timeout:        cfg.StickySessionWaitTimeout,
+						MaxWaiting:     cfg.StickySessionMaxWaiting,
+					},
+				}, nil
+			}
+		}
+		return &AccountSelectionResult{
+			Account: account,
+			WaitPlan: &AccountWaitPlan{
+				AccountID:      account.ID,
+				MaxConcurrency: account.Concurrency,
+				Timeout:        cfg.FallbackWaitTimeout,
+				MaxWaiting:     cfg.FallbackMaxWaiting,
+			},
+		}, nil
+	}
+
+	platform, hasForcePlatform, err := s.resolvePlatform(ctx, groupID)
+	if err != nil {
+		return nil, err
+	}
+	preferOAuth := platform == PlatformGemini
+
+	accounts, useMixed, err := s.listSchedulableAccounts(ctx, groupID, platform, hasForcePlatform)
+	if err != nil {
+		return nil, err
+	}
+	if len(accounts) == 0 {
+		return nil, errors.New("no available accounts")
+	}
+
+	isExcluded := func(accountID int64) bool {
+		if excludedIDs == nil {
+			return false
+		}
+		_, excluded := excludedIDs[accountID]
+		return excluded
+	}
+
+	// ============ Layer 1: 粘性会话优先 ============
+	if sessionHash != "" {
+		accountID, err := s.cache.GetSessionAccountID(ctx, sessionHash)
+		if err == nil && accountID > 0 && !isExcluded(accountID) {
+			account, err := s.accountRepo.GetByID(ctx, accountID)
+			if err == nil && s.isAccountAllowedForPlatform(account, platform, useMixed) &&
+				account.IsSchedulable() &&
+				(requestedModel == "" || s.isModelSupportedByAccount(account, requestedModel)) {
+				result, err := s.tryAcquireAccountSlot(ctx, accountID, account.Concurrency)
+				if err == nil && result.Acquired {
+					_ = s.cache.RefreshSessionTTL(ctx, sessionHash, stickySessionTTL)
+					return &AccountSelectionResult{
+						Account:     account,
+						Acquired:    true,
+						ReleaseFunc: result.ReleaseFunc,
+					}, nil
+				}
+
+				waitingCount, _ := s.concurrencyService.GetAccountWaitingCount(ctx, accountID)
+				if waitingCount < cfg.StickySessionMaxWaiting {
+					return &AccountSelectionResult{
+						Account: account,
+						WaitPlan: &AccountWaitPlan{
+							AccountID:      accountID,
+							MaxConcurrency: account.Concurrency,
+							Timeout:        cfg.StickySessionWaitTimeout,
+							MaxWaiting:     cfg.StickySessionMaxWaiting,
+						},
+					}, nil
+				}
+			}
+		}
+	}
+
+	// ============ Layer 2: 负载感知选择 ============
+	candidates := make([]*Account, 0, len(accounts))
+	for i := range accounts {
+		acc := &accounts[i]
+		if isExcluded(acc.ID) {
+			continue
+		}
+		if !s.isAccountAllowedForPlatform(acc, platform, useMixed) {
+			continue
+		}
+		if requestedModel != "" && !s.isModelSupportedByAccount(acc, requestedModel) {
+			continue
+		}
+		candidates = append(candidates, acc)
+	}
+
+	if len(candidates) == 0 {
+		return nil, errors.New("no available accounts")
+	}
+
+	accountLoads := make([]AccountWithConcurrency, 0, len(candidates))
+	for _, acc := range candidates {
+		accountLoads = append(accountLoads, AccountWithConcurrency{
+			ID:             acc.ID,
+			MaxConcurrency: acc.Concurrency,
+		})
+	}
+
+	loadMap, err := s.concurrencyService.GetAccountsLoadBatch(ctx, accountLoads)
+	if err != nil {
+		if result, ok := s.tryAcquireByLegacyOrder(ctx, candidates, sessionHash, preferOAuth); ok {
+			return result, nil
+		}
+	} else {
+		type accountWithLoad struct {
+			account  *Account
+			loadInfo *AccountLoadInfo
+		}
+		var available []accountWithLoad
+		for _, acc := range candidates {
+			loadInfo := loadMap[acc.ID]
+			if loadInfo == nil {
+				loadInfo = &AccountLoadInfo{AccountID: acc.ID}
+			}
+			if loadInfo.LoadRate < 100 {
+				available = append(available, accountWithLoad{
+					account:  acc,
+					loadInfo: loadInfo,
+				})
+			}
+		}
+
+		if len(available) > 0 {
+			sort.SliceStable(available, func(i, j int) bool {
+				a, b := available[i], available[j]
+				if a.account.Priority != b.account.Priority {
+					return a.account.Priority < b.account.Priority
+				}
+				if a.loadInfo.LoadRate != b.loadInfo.LoadRate {
+					return a.loadInfo.LoadRate < b.loadInfo.LoadRate
+				}
+				switch {
+				case a.account.LastUsedAt == nil && b.account.LastUsedAt != nil:
+					return true
+				case a.account.LastUsedAt != nil && b.account.LastUsedAt == nil:
+					return false
+				case a.account.LastUsedAt == nil && b.account.LastUsedAt == nil:
+					if preferOAuth && a.account.Type != b.account.Type {
+						return a.account.Type == AccountTypeOAuth
+					}
+					return false
+				default:
+					return a.account.LastUsedAt.Before(*b.account.LastUsedAt)
+				}
+			})
+
+			for _, item := range available {
+				result, err := s.tryAcquireAccountSlot(ctx, item.account.ID, item.account.Concurrency)
+				if err == nil && result.Acquired {
+					if sessionHash != "" {
+						_ = s.cache.SetSessionAccountID(ctx, sessionHash, item.account.ID, stickySessionTTL)
+					}
+					return &AccountSelectionResult{
+						Account:     item.account,
+						Acquired:    true,
+						ReleaseFunc: result.ReleaseFunc,
+					}, nil
+				}
+			}
+		}
+	}
+
+	// ============ Layer 3: 兜底排队 ============
+	sortAccountsByPriorityAndLastUsed(candidates, preferOAuth)
+	for _, acc := range candidates {
+		return &AccountSelectionResult{
+			Account: acc,
+			WaitPlan: &AccountWaitPlan{
+				AccountID:      acc.ID,
+				MaxConcurrency: acc.Concurrency,
+				Timeout:        cfg.FallbackWaitTimeout,
+				MaxWaiting:     cfg.FallbackMaxWaiting,
+			},
+		}, nil
+	}
+	return nil, errors.New("no available accounts")
+}
+
+func (s *GatewayService) tryAcquireByLegacyOrder(ctx context.Context, candidates []*Account, sessionHash string, preferOAuth bool) (*AccountSelectionResult, bool) {
+	ordered := append([]*Account(nil), candidates...)
+	sortAccountsByPriorityAndLastUsed(ordered, preferOAuth)
+
+	for _, acc := range ordered {
+		result, err := s.tryAcquireAccountSlot(ctx, acc.ID, acc.Concurrency)
+		if err == nil && result.Acquired {
+			if sessionHash != "" {
+				_ = s.cache.SetSessionAccountID(ctx, sessionHash, acc.ID, stickySessionTTL)
+			}
+			return &AccountSelectionResult{
+				Account:     acc,
+				Acquired:    true,
+				ReleaseFunc: result.ReleaseFunc,
+			}, true
+		}
+	}
+
+	return nil, false
+}
+
+func (s *GatewayService) schedulingConfig() config.GatewaySchedulingConfig {
+	if s.cfg != nil {
+		return s.cfg.Gateway.Scheduling
+	}
+	return config.GatewaySchedulingConfig{
+		StickySessionMaxWaiting:  3,
+		StickySessionWaitTimeout: 45 * time.Second,
+		FallbackWaitTimeout:      30 * time.Second,
+		FallbackMaxWaiting:       100,
+		LoadBatchEnabled:         true,
+		SlotCleanupInterval:      30 * time.Second,
+	}
+}
+
+func (s *GatewayService) resolvePlatform(ctx context.Context, groupID *int64) (string, bool, error) {
+	forcePlatform, hasForcePlatform := ctx.Value(ctxkey.ForcePlatform).(string)
+	if hasForcePlatform && forcePlatform != "" {
+		return forcePlatform, true, nil
+	}
+	if groupID != nil {
+		group, err := s.groupRepo.GetByID(ctx, *groupID)
+		if err != nil {
+			return "", false, fmt.Errorf("get group failed: %w", err)
+		}
+		return group.Platform, false, nil
+	}
+	return PlatformAnthropic, false, nil
+}
+
+func (s *GatewayService) listSchedulableAccounts(ctx context.Context, groupID *int64, platform string, hasForcePlatform bool) ([]Account, bool, error) {
+	useMixed := (platform == PlatformAnthropic || platform == PlatformGemini) && !hasForcePlatform
+	if useMixed {
+		platforms := []string{platform, PlatformAntigravity}
+		var accounts []Account
+		var err error
+		if groupID != nil {
+			accounts, err = s.accountRepo.ListSchedulableByGroupIDAndPlatforms(ctx, *groupID, platforms)
+		} else {
+			accounts, err = s.accountRepo.ListSchedulableByPlatforms(ctx, platforms)
+		}
+		if err != nil {
+			return nil, useMixed, err
+		}
+		filtered := make([]Account, 0, len(accounts))
+		for _, acc := range accounts {
+			if acc.Platform == PlatformAntigravity && !acc.IsMixedSchedulingEnabled() {
+				continue
+			}
+			filtered = append(filtered, acc)
+		}
+		return filtered, useMixed, nil
+	}
+
+	var accounts []Account
+	var err error
+	if s.cfg != nil && s.cfg.RunMode == config.RunModeSimple {
+		accounts, err = s.accountRepo.ListSchedulableByPlatform(ctx, platform)
+	} else if groupID != nil {
+		accounts, err = s.accountRepo.ListSchedulableByGroupIDAndPlatform(ctx, *groupID, platform)
+		if err == nil && len(accounts) == 0 && hasForcePlatform {
+			accounts, err = s.accountRepo.ListSchedulableByPlatform(ctx, platform)
+		}
+	} else {
+		accounts, err = s.accountRepo.ListSchedulableByPlatform(ctx, platform)
+	}
+	if err != nil {
+		return nil, useMixed, err
+	}
+	return accounts, useMixed, nil
+}
+
+func (s *GatewayService) isAccountAllowedForPlatform(account *Account, platform string, useMixed bool) bool {
+	if account == nil {
+		return false
+	}
+	if useMixed {
+		if account.Platform == platform {
+			return true
+		}
+		return account.Platform == PlatformAntigravity && account.IsMixedSchedulingEnabled()
+	}
+	return account.Platform == platform
+}
+
+func (s *GatewayService) tryAcquireAccountSlot(ctx context.Context, accountID int64, maxConcurrency int) (*AcquireResult, error) {
+	if s.concurrencyService == nil {
+		return &AcquireResult{Acquired: true, ReleaseFunc: func() {}}, nil
+	}
+	return s.concurrencyService.AcquireAccountSlot(ctx, accountID, maxConcurrency)
+}
+
+func sortAccountsByPriorityAndLastUsed(accounts []*Account, preferOAuth bool) {
+	sort.SliceStable(accounts, func(i, j int) bool {
+		a, b := accounts[i], accounts[j]
+		if a.Priority != b.Priority {
+			return a.Priority < b.Priority
+		}
+		switch {
+		case a.LastUsedAt == nil && b.LastUsedAt != nil:
+			return true
+		case a.LastUsedAt != nil && b.LastUsedAt == nil:
+			return false
+		case a.LastUsedAt == nil && b.LastUsedAt == nil:
+			if preferOAuth && a.Type != b.Type {
+				return a.Type == AccountTypeOAuth
+			}
+			return false
+		default:
+			return a.LastUsedAt.Before(*b.LastUsedAt)
+		}
+	})
+}
+
 // selectAccountForModelWithPlatform 选择单平台账户（完全隔离）
 func (s *GatewayService) selectAccountForModelWithPlatform(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}, platform string) (*Account, error) {
+	preferOAuth := platform == PlatformGemini
 	// 1. 查询粘性会话
 	if sessionHash != "" {
 		accountID, err := s.cache.GetSessionAccountID(ctx, sessionHash)
@@ -389,7 +762,9 @@ func (s *GatewayService) selectAccountForModelWithPlatform(ctx context.Context,
 			case acc.LastUsedAt != nil && selected.LastUsedAt == nil:
 				// keep selected (never used is preferred)
 			case acc.LastUsedAt == nil && selected.LastUsedAt == nil:
-				// keep selected (both never used)
+				if preferOAuth && acc.Type != selected.Type && acc.Type == AccountTypeOAuth {
+					selected = acc
+				}
 			default:
 				if acc.LastUsedAt.Before(*selected.LastUsedAt) {
 					selected = acc
@@ -419,6 +794,7 @@ func (s *GatewayService) selectAccountForModelWithPlatform(ctx context.Context,
 // 查询原生平台账户 + 启用 mixed_scheduling 的 antigravity 账户
 func (s *GatewayService) selectAccountWithMixedScheduling(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}, nativePlatform string) (*Account, error) {
 	platforms := []string{nativePlatform, PlatformAntigravity}
+	preferOAuth := nativePlatform == PlatformGemini
 
 	// 1. 查询粘性会话
 	if sessionHash != "" {
@@ -478,7 +854,9 @@ func (s *GatewayService) selectAccountWithMixedScheduling(ctx context.Context, g
 			case acc.LastUsedAt != nil && selected.LastUsedAt == nil:
 				// keep selected (never used is preferred)
 			case acc.LastUsedAt == nil && selected.LastUsedAt == nil:
-				// keep selected (both never used)
+				if preferOAuth && acc.Platform == PlatformGemini && selected.Platform == PlatformGemini && acc.Type != selected.Type && acc.Type == AccountTypeOAuth {
+					selected = acc
+				}
 			default:
 				if acc.LastUsedAt.Before(*selected.LastUsedAt) {
 					selected = acc
@@ -515,24 +893,10 @@ func (s *GatewayService) isModelSupportedByAccount(account *Account, requestedMo
 }
 
 // IsAntigravityModelSupported 检查 Antigravity 平台是否支持指定模型
+// 所有 claude- 和 gemini- 前缀的模型都能通过映射或透传支持
 func IsAntigravityModelSupported(requestedModel string) bool {
-	// 直接支持的模型
-	if antigravitySupportedModels[requestedModel] {
-		return true
-	}
-	// 可映射的模型
-	if _, ok := antigravityModelMapping[requestedModel]; ok {
-		return true
-	}
-	// Gemini 前缀透传
-	if strings.HasPrefix(requestedModel, "gemini-") {
-		return true
-	}
-	// Claude 模型支持（通过默认映射到 claude-sonnet-4-5）
-	if strings.HasPrefix(requestedModel, "claude-") {
-		return true
-	}
-	return false
+	return strings.HasPrefix(requestedModel, "claude-") ||
+		strings.HasPrefix(requestedModel, "gemini-")
 }
 
 // GetAccessToken 获取账号凭证
@@ -684,6 +1048,30 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 
 	// 处理错误响应（不可重试的错误）
 	if resp.StatusCode >= 400 {
+		// 可选：对部分 400 触发 failover（默认关闭以保持语义）
+		if resp.StatusCode == 400 && s.cfg != nil && s.cfg.Gateway.FailoverOn400 {
+			respBody, readErr := io.ReadAll(resp.Body)
+			if readErr != nil {
+				// ReadAll failed, fall back to normal error handling without consuming the stream
+				return s.handleErrorResponse(ctx, resp, c, account)
+			}
+			_ = resp.Body.Close()
+			resp.Body = io.NopCloser(bytes.NewReader(respBody))
+
+			if s.shouldFailoverOn400(respBody) {
+				if s.cfg.Gateway.LogUpstreamErrorBody {
+					log.Printf(
+						"Account %d: 400 error, attempting failover: %s",
+						account.ID,
+						truncateForLog(respBody, s.cfg.Gateway.LogUpstreamErrorBodyMaxBytes),
+					)
+				} else {
+					log.Printf("Account %d: 400 error, attempting failover", account.ID)
+				}
+				s.handleFailoverSideEffects(ctx, resp, account)
+				return nil, &UpstreamFailoverError{StatusCode: resp.StatusCode}
+			}
+		}
 		return s.handleErrorResponse(ctx, resp, c, account)
 	}
 
@@ -786,6 +1174,13 @@ func (s *GatewayService) buildUpstreamRequest(ctx context.Context, c *gin.Contex
 	// 处理anthropic-beta header（OAuth账号需要特殊处理）
 	if tokenType == "oauth" {
 		req.Header.Set("anthropic-beta", s.getBetaHeader(modelID, c.GetHeader("anthropic-beta")))
+	} else if s.cfg != nil && s.cfg.Gateway.InjectBetaForApiKey && req.Header.Get("anthropic-beta") == "" {
+		// API-key：仅在请求显式使用 beta 特性且客户端未提供时，按需补齐（默认关闭）
+		if requestNeedsBetaFeatures(body) {
+			if beta := defaultApiKeyBetaHeader(body); beta != "" {
+				req.Header.Set("anthropic-beta", beta)
+			}
+		}
 	}
 
 	return req, nil
@@ -838,6 +1233,83 @@ func (s *GatewayService) getBetaHeader(modelID string, clientBetaHeader string)
 	return claude.DefaultBetaHeader
 }
 
+func requestNeedsBetaFeatures(body []byte) bool {
+	tools := gjson.GetBytes(body, "tools")
+	if tools.Exists() && tools.IsArray() && len(tools.Array()) > 0 {
+		return true
+	}
+	if strings.EqualFold(gjson.GetBytes(body, "thinking.type").String(), "enabled") {
+		return true
+	}
+	return false
+}
+
+func defaultApiKeyBetaHeader(body []byte) string {
+	modelID := gjson.GetBytes(body, "model").String()
+	if strings.Contains(strings.ToLower(modelID), "haiku") {
+		return claude.ApiKeyHaikuBetaHeader
+	}
+	return claude.ApiKeyBetaHeader
+}
+
+func truncateForLog(b []byte, maxBytes int) string {
+	if maxBytes <= 0 {
+		maxBytes = 2048
+	}
+	if len(b) > maxBytes {
+		b = b[:maxBytes]
+	}
+	s := string(b)
+	// 保持一行，避免污染日志格式
+	s = strings.ReplaceAll(s, "\n", "\\n")
+	s = strings.ReplaceAll(s, "\r", "\\r")
+	return s
+}
+
+func (s *GatewayService) shouldFailoverOn400(respBody []byte) bool {
+	// 只对“可能是兼容性差异导致”的 400 允许切换，避免无意义重试。
+	// 默认保守：无法识别则不切换。
+	msg := strings.ToLower(strings.TrimSpace(extractUpstreamErrorMessage(respBody)))
+	if msg == "" {
+		return false
+	}
+
+	// 缺少/错误的 beta header：换账号/链路可能成功（尤其是混合调度时）。
+	// 更精确匹配 beta 相关的兼容性问题，避免误触发切换。
+	if strings.Contains(msg, "anthropic-beta") ||
+		strings.Contains(msg, "beta feature") ||
+		strings.Contains(msg, "requires beta") {
+		return true
+	}
+
+	// thinking/tool streaming 等兼容性约束（常见于中间转换链路）
+	if strings.Contains(msg, "thinking") || strings.Contains(msg, "thought_signature") || strings.Contains(msg, "signature") {
+		return true
+	}
+	if strings.Contains(msg, "tool_use") || strings.Contains(msg, "tool_result") || strings.Contains(msg, "tools") {
+		return true
+	}
+
+	return false
+}
+
+func extractUpstreamErrorMessage(body []byte) string {
+	// Claude 风格：{"type":"error","error":{"type":"...","message":"..."}}
+	if m := gjson.GetBytes(body, "error.message").String(); strings.TrimSpace(m) != "" {
+		inner := strings.TrimSpace(m)
+		// 有些上游会把完整 JSON 作为字符串塞进 message
+		if strings.HasPrefix(inner, "{") {
+			if innerMsg := gjson.Get(inner, "error.message").String(); strings.TrimSpace(innerMsg) != "" {
+				return innerMsg
+			}
+		}
+		return m
+	}
+
+	// 兜底：尝试顶层 message
+	return gjson.GetBytes(body, "message").String()
+}
+
 func (s *GatewayService) handleErrorResponse(ctx context.Context, resp *http.Response, c *gin.Context, account *Account) (*ForwardResult, error) {
 	body, _ := io.ReadAll(resp.Body)
 
@@ -850,6 +1322,16 @@ func (s *GatewayService) handleErrorResponse(ctx context.Context, resp *http.Res
 
 	switch resp.StatusCode {
 	case 400:
+		// 仅记录上游错误摘要（避免输出请求内容）；需要时可通过配置打开
+		if s.cfg != nil && s.cfg.Gateway.LogUpstreamErrorBody {
+			log.Printf(
+				"Upstream 400 error (account=%d platform=%s type=%s): %s",
+				account.ID,
+				account.Platform,
+				account.Type,
+				truncateForLog(body, s.cfg.Gateway.LogUpstreamErrorBodyMaxBytes),
+			)
+		}
 		c.Data(http.StatusBadRequest, "application/json", body)
 		return nil, fmt.Errorf("upstream error: %d", resp.StatusCode)
 	case 401:
@@ -1329,6 +1811,18 @@ func (s *GatewayService) ForwardCountTokens(ctx context.Context, c *gin.Context,
 		// 标记账号状态（429/529等）
 		s.rateLimitService.HandleUpstreamError(ctx, account, resp.StatusCode, resp.Header, respBody)
 
+		// 记录上游错误摘要便于排障（不回显请求内容）
+		if s.cfg != nil && s.cfg.Gateway.LogUpstreamErrorBody {
+			log.Printf(
+				"count_tokens upstream error %d (account=%d platform=%s type=%s): %s",
+				resp.StatusCode,
+				account.ID,
+				account.Platform,
+				account.Type,
+				truncateForLog(respBody, s.cfg.Gateway.LogUpstreamErrorBodyMaxBytes),
+			)
+		}
+
 		// 返回简化的错误响应
 		errMsg := "Upstream request failed"
 		switch resp.StatusCode {
@@ -1409,6 +1903,13 @@ func (s *GatewayService) buildCountTokensRequest(ctx context.Context, c *gin.Con
 	// OAuth 账号：处理 anthropic-beta header
 	if tokenType == "oauth" {
 		req.Header.Set("anthropic-beta", s.getBetaHeader(modelID, c.GetHeader("anthropic-beta")))
+	} else if s.cfg != nil && s.cfg.Gateway.InjectBetaForApiKey && req.Header.Get("anthropic-beta") == "" {
+		// API-key：与 messages 同步的按需 beta 注入（默认关闭）
+		if requestNeedsBetaFeatures(body) {
+			if beta := defaultApiKeyBetaHeader(body); beta != "" {
+				req.Header.Set("anthropic-beta", beta)
+			}
+		}
 	}
 
 	return req, nil
@@ -1424,3 +1925,58 @@ func (s *GatewayService) countTokensError(c *gin.Context, status int, errType, m
 		},
 	})
 }
+
+// GetAvailableModels returns the list of models available for a group
+// It aggregates model_mapping keys from all schedulable accounts in the group
+func (s *GatewayService) GetAvailableModels(ctx context.Context, groupID *int64, platform string) []string {
+	var accounts []Account
+	var err error
+
+	if groupID != nil {
+		accounts, err = s.accountRepo.ListSchedulableByGroupID(ctx, *groupID)
+	} else {
+		accounts, err = s.accountRepo.ListSchedulable(ctx)
+	}
+
+	if err != nil || len(accounts) == 0 {
+		return nil
+	}
+
+	// Filter by platform if specified
+	if platform != "" {
+		filtered := make([]Account, 0)
+		for _, acc := range accounts {
+			if acc.Platform == platform {
+				filtered = append(filtered, acc)
+			}
+		}
+		accounts = filtered
+	}
+
+	// Collect unique models from all accounts
+	modelSet := make(map[string]struct{})
+	hasAnyMapping := false
+
+	for _, acc := range accounts {
+		mapping := acc.GetModelMapping()
+		if len(mapping) > 0 {
+			hasAnyMapping = true
+			for model := range mapping {
+				modelSet[model] = struct{}{}
+			}
+		}
+	}
+
+	// If no account has model_mapping, return nil (use default)
+	if !hasAnyMapping {
+		return nil
+	}
+
+	// Convert to slice
+	models := make([]string, 0, len(modelSet))
+	for model := range modelSet {
+		models = append(models, model)
+	}
+
+	return models
+}

backend/internal/service/gemini_messages_compat_service.go

@@ -116,6 +116,17 @@ func (s *GeminiMessagesCompatService) SelectAccountForModelWithExclusions(ctx co
 						valid = true
 					}
 					if valid {
+						usable := true
+						if s.rateLimitService != nil && requestedModel != "" {
+							ok, err := s.rateLimitService.PreCheckUsage(ctx, account, requestedModel)
+							if err != nil {
+								log.Printf("[Gemini PreCheck] Account %d precheck error: %v", account.ID, err)
+							}
+							if !ok {
+								usable = false
+							}
+						}
+						if usable {
 							_ = s.cache.RefreshSessionTTL(ctx, cacheKey, geminiStickySessionTTL)
 							return account, nil
 						}
@@ -123,6 +134,7 @@ func (s *GeminiMessagesCompatService) SelectAccountForModelWithExclusions(ctx co
 				}
 			}
 		}
+	}
 
 	// 查询可调度账户（强制平台模式：优先按分组查找，找不到再查全部）
 	var accounts []Account
@@ -157,6 +169,15 @@ func (s *GeminiMessagesCompatService) SelectAccountForModelWithExclusions(ctx co
 		if requestedModel != "" && !s.isModelSupportedByAccount(acc, requestedModel) {
 			continue
 		}
+		if s.rateLimitService != nil && requestedModel != "" {
+			ok, err := s.rateLimitService.PreCheckUsage(ctx, acc, requestedModel)
+			if err != nil {
+				log.Printf("[Gemini PreCheck] Account %d precheck error: %v", acc.ID, err)
+			}
+			if !ok {
+				continue
+			}
+		}
 		if selected == nil {
 			selected = acc
 			continue
@@ -1886,13 +1907,44 @@ func (s *GeminiMessagesCompatService) handleGeminiUpstreamError(ctx context.Cont
 	if statusCode != 429 {
 		return
 	}
+
+	oauthType := account.GeminiOAuthType()
+	tierID := account.GeminiTierID()
+	projectID := strings.TrimSpace(account.GetCredential("project_id"))
+	isCodeAssist := account.IsGeminiCodeAssist()
+
 	resetAt := ParseGeminiRateLimitResetTime(body)
 	if resetAt == nil {
-		ra := time.Now().Add(5 * time.Minute)
+		// 根据账号类型使用不同的默认重置时间
+		var ra time.Time
+		if isCodeAssist {
+			// Code Assist: fallback cooldown by tier
+			cooldown := geminiCooldownForTier(tierID)
+			if s.rateLimitService != nil {
+				cooldown = s.rateLimitService.GeminiCooldown(ctx, account)
+			}
+			ra = time.Now().Add(cooldown)
+			log.Printf("[Gemini 429] Account %d (Code Assist, tier=%s, project=%s) rate limited, cooldown=%v", account.ID, tierID, projectID, time.Until(ra).Truncate(time.Second))
+		} else {
+			// API Key / AI Studio OAuth: PST 午夜
+			if ts := nextGeminiDailyResetUnix(); ts != nil {
+				ra = time.Unix(*ts, 0)
+				log.Printf("[Gemini 429] Account %d (API Key/AI Studio, type=%s) rate limited, reset at PST midnight (%v)", account.ID, account.Type, ra)
+			} else {
+				// 兜底：5 分钟
+				ra = time.Now().Add(5 * time.Minute)
+				log.Printf("[Gemini 429] Account %d rate limited, fallback to 5min", account.ID)
+			}
+		}
 		_ = s.accountRepo.SetRateLimited(ctx, account.ID, ra)
 		return
 	}
-	_ = s.accountRepo.SetRateLimited(ctx, account.ID, time.Unix(*resetAt, 0))
+
+	// 使用解析到的重置时间
+	resetTime := time.Unix(*resetAt, 0)
+	_ = s.accountRepo.SetRateLimited(ctx, account.ID, resetTime)
+	log.Printf("[Gemini 429] Account %d rate limited until %v (oauth_type=%s, tier=%s)",
+		account.ID, resetTime, oauthType, tierID)
 }
 
 // ParseGeminiRateLimitResetTime 解析 Gemini 格式的 429 响应，返回重置时间的 Unix 时间戳
@@ -1948,16 +2000,7 @@ func looksLikeGeminiDailyQuota(message string) bool {
 }
 
 func nextGeminiDailyResetUnix() *int64 {
-	loc, err := time.LoadLocation("America/Los_Angeles")
-	if err != nil {
-		// Fallback: PST without DST.
-		loc = time.FixedZone("PST", -8*3600)
-	}
-	now := time.Now().In(loc)
-	reset := time.Date(now.Year(), now.Month(), now.Day(), 0, 5, 0, 0, loc)
-	if !reset.After(now) {
-		reset = reset.Add(24 * time.Hour)
-	}
+	reset := geminiDailyResetTime(time.Now())
 	ts := reset.Unix()
 	return &ts
 }
@@ -2278,11 +2321,13 @@ func convertClaudeToolsToGeminiTools(tools any) []any {
 				"properties": map[string]any{},
 			}
 		}
+		// 清理 JSON Schema
+		cleanedParams := cleanToolSchema(params)
 
 		funcDecls = append(funcDecls, map[string]any{
 			"name":        name,
 			"description": desc,
-			"parameters":  params,
+			"parameters":  cleanedParams,
 		})
 	}
 
@@ -2296,6 +2341,41 @@ func convertClaudeToolsToGeminiTools(tools any) []any {
 	}
 }
 
+// cleanToolSchema 清理工具的 JSON Schema，移除 Gemini 不支持的字段
+func cleanToolSchema(schema any) any {
+	if schema == nil {
+		return nil
+	}
+
+	switch v := schema.(type) {
+	case map[string]any:
+		cleaned := make(map[string]any)
+		for key, value := range v {
+			// 跳过不支持的字段
+			if key == "$schema" || key == "$id" || key == "$ref" ||
+				key == "additionalProperties" || key == "minLength" ||
+				key == "maxLength" || key == "minItems" || key == "maxItems" {
+				continue
+			}
+			// 递归清理嵌套对象
+			cleaned[key] = cleanToolSchema(value)
+		}
+		// 规范化 type 字段为大写
+		if typeVal, ok := cleaned["type"].(string); ok {
+			cleaned["type"] = strings.ToUpper(typeVal)
+		}
+		return cleaned
+	case []any:
+		cleaned := make([]any, len(v))
+		for i, item := range v {
+			cleaned[i] = cleanToolSchema(item)
+		}
+		return cleaned
+	default:
+		return v
+	}
+}
+
 func convertClaudeGenerationConfig(req map[string]any) map[string]any {
 	out := make(map[string]any)
 	if mt, ok := asInt(req["max_tokens"]); ok && mt > 0 {

backend/internal/service/gemini_messages_compat_service_test.go

+package service
+
+import (
+	"testing"
+)
+
+// TestConvertClaudeToolsToGeminiTools_CustomType 测试custom类型工具转换
+func TestConvertClaudeToolsToGeminiTools_CustomType(t *testing.T) {
+	tests := []struct {
+		name        string
+		tools       any
+		expectedLen int
+		description string
+	}{
+		{
+			name: "Standard tools",
+			tools: []any{
+				map[string]any{
+					"name":         "get_weather",
+					"description":  "Get weather info",
+					"input_schema": map[string]any{"type": "object"},
+				},
+			},
+			expectedLen: 1,
+			description: "标准工具格式应该正常转换",
+		},
+		{
+			name: "Custom type tool (MCP format)",
+			tools: []any{
+				map[string]any{
+					"type": "custom",
+					"name": "mcp_tool",
+					"custom": map[string]any{
+						"description":  "MCP tool description",
+						"input_schema": map[string]any{"type": "object"},
+					},
+				},
+			},
+			expectedLen: 1,
+			description: "Custom类型工具应该从custom字段读取",
+		},
+		{
+			name: "Mixed standard and custom tools",
+			tools: []any{
+				map[string]any{
+					"name":         "standard_tool",
+					"description":  "Standard",
+					"input_schema": map[string]any{"type": "object"},
+				},
+				map[string]any{
+					"type": "custom",
+					"name": "custom_tool",
+					"custom": map[string]any{
+						"description":  "Custom",
+						"input_schema": map[string]any{"type": "object"},
+					},
+				},
+			},
+			expectedLen: 1,
+			description: "混合工具应该都能正确转换",
+		},
+		{
+			name: "Custom tool without custom field",
+			tools: []any{
+				map[string]any{
+					"type": "custom",
+					"name": "invalid_custom",
+					// 缺少 custom 字段
+				},
+			},
+			expectedLen: 0, // 应该被跳过
+			description: "缺少custom字段的custom工具应该被跳过",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := convertClaudeToolsToGeminiTools(tt.tools)
+
+			if tt.expectedLen == 0 {
+				if result != nil {
+					t.Errorf("%s: expected nil result, got %v", tt.description, result)
+				}
+				return
+			}
+
+			if result == nil {
+				t.Fatalf("%s: expected non-nil result", tt.description)
+			}
+
+			if len(result) != 1 {
+				t.Errorf("%s: expected 1 tool declaration, got %d", tt.description, len(result))
+				return
+			}
+
+			toolDecl, ok := result[0].(map[string]any)
+			if !ok {
+				t.Fatalf("%s: result[0] is not map[string]any", tt.description)
+			}
+
+			funcDecls, ok := toolDecl["functionDeclarations"].([]any)
+			if !ok {
+				t.Fatalf("%s: functionDeclarations is not []any", tt.description)
+			}
+
+			toolsArr, _ := tt.tools.([]any)
+			expectedFuncCount := 0
+			for _, tool := range toolsArr {
+				toolMap, _ := tool.(map[string]any)
+				if toolMap["name"] != "" {
+					// 检查是否为有效的custom工具
+					if toolMap["type"] == "custom" {
+						if toolMap["custom"] != nil {
+							expectedFuncCount++
+						}
+					} else {
+						expectedFuncCount++
+					}
+				}
+			}
+
+			if len(funcDecls) != expectedFuncCount {
+				t.Errorf("%s: expected %d function declarations, got %d",
+					tt.description, expectedFuncCount, len(funcDecls))
+			}
+		})
+	}
+}

backend/internal/service/gemini_multiplatform_test.go

@@ -25,6 +25,16 @@ func (m *mockAccountRepoForGemini) GetByID(ctx context.Context, id int64) (*Acco
 	return nil, errors.New("account not found")
 }
 
+func (m *mockAccountRepoForGemini) GetByIDs(ctx context.Context, ids []int64) ([]*Account, error) {
+	var result []*Account
+	for _, id := range ids {
+		if acc, ok := m.accountsByID[id]; ok {
+			result = append(result, acc)
+		}
+	}
+	return result, nil
+}
+
 func (m *mockAccountRepoForGemini) ExistsByID(ctx context.Context, id int64) (bool, error) {
 	if m.accountsByID == nil {
 		return false, nil

backend/internal/service/gemini_oauth_service.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -16,6 +17,26 @@ import (
 	"github.com/Wei-Shaw/sub2api/internal/pkg/httpclient"
 )
 
+const (
+	TierAIPremium          = "AI_PREMIUM"
+	TierGoogleOneStandard  = "GOOGLE_ONE_STANDARD"
+	TierGoogleOneBasic     = "GOOGLE_ONE_BASIC"
+	TierFree               = "FREE"
+	TierGoogleOneUnknown   = "GOOGLE_ONE_UNKNOWN"
+	TierGoogleOneUnlimited = "GOOGLE_ONE_UNLIMITED"
+)
+
+const (
+	GB = 1024 * 1024 * 1024
+	TB = 1024 * GB
+
+	StorageTierUnlimited = 100 * TB // 100TB
+	StorageTierAIPremium = 2 * TB   // 2TB
+	StorageTierStandard  = 200 * GB // 200GB
+	StorageTierBasic     = 100 * GB // 100GB
+	StorageTierFree      = 15 * GB  // 15GB
+)
+
 type GeminiOAuthService struct {
 	sessionStore *geminicli.SessionStore
 	proxyRepo    ProxyRepository
@@ -88,13 +109,14 @@ func (s *GeminiOAuthService) GenerateAuthURL(ctx context.Context, proxyID *int64
 
 	// OAuth client selection:
 	// - code_assist: always use built-in Gemini CLI OAuth client (public), regardless of configured client_id/secret.
+	// - google_one: same as code_assist, uses built-in client for personal Google accounts.
 	// - ai_studio: requires a user-provided OAuth client.
 	oauthCfg := geminicli.OAuthConfig{
 		ClientID:     s.cfg.Gemini.OAuth.ClientID,
 		ClientSecret: s.cfg.Gemini.OAuth.ClientSecret,
 		Scopes:       s.cfg.Gemini.OAuth.Scopes,
 	}
-	if oauthType == "code_assist" {
+	if oauthType == "code_assist" || oauthType == "google_one" {
 		oauthCfg.ClientID = ""
 		oauthCfg.ClientSecret = ""
 	}
@@ -163,6 +185,144 @@ type GeminiTokenInfo struct {
 	Scope        string         `json:"scope,omitempty"`
 	ProjectID    string         `json:"project_id,omitempty"`
 	OAuthType    string         `json:"oauth_type,omitempty"` // "code_assist" 或 "ai_studio"
+	TierID       string         `json:"tier_id,omitempty"`    // Gemini Code Assist tier: LEGACY/PRO/ULTRA
+	Extra        map[string]any `json:"extra,omitempty"`      // Drive metadata
+}
+
+// validateTierID validates tier_id format and length
+func validateTierID(tierID string) error {
+	if tierID == "" {
+		return nil // Empty is allowed
+	}
+	if len(tierID) > 64 {
+		return fmt.Errorf("tier_id exceeds maximum length of 64 characters")
+	}
+	// Allow alphanumeric, underscore, hyphen, and slash (for tier paths)
+	if !regexp.MustCompile(`^[a-zA-Z0-9_/-]+$`).MatchString(tierID) {
+		return fmt.Errorf("tier_id contains invalid characters")
+	}
+	return nil
+}
+
+// extractTierIDFromAllowedTiers extracts tierID from LoadCodeAssist response
+// Prioritizes IsDefault tier, falls back to first non-empty tier
+func extractTierIDFromAllowedTiers(allowedTiers []geminicli.AllowedTier) string {
+	tierID := "LEGACY"
+	// First pass: look for default tier
+	for _, tier := range allowedTiers {
+		if tier.IsDefault && strings.TrimSpace(tier.ID) != "" {
+			tierID = strings.TrimSpace(tier.ID)
+			break
+		}
+	}
+	// Second pass: if still LEGACY, take first non-empty tier
+	if tierID == "LEGACY" {
+		for _, tier := range allowedTiers {
+			if strings.TrimSpace(tier.ID) != "" {
+				tierID = strings.TrimSpace(tier.ID)
+				break
+			}
+		}
+	}
+	return tierID
+}
+
+// inferGoogleOneTier infers Google One tier from Drive storage limit
+func inferGoogleOneTier(storageBytes int64) string {
+	if storageBytes <= 0 {
+		return TierGoogleOneUnknown
+	}
+
+	if storageBytes > StorageTierUnlimited {
+		return TierGoogleOneUnlimited
+	}
+	if storageBytes >= StorageTierAIPremium {
+		return TierAIPremium
+	}
+	if storageBytes >= StorageTierStandard {
+		return TierGoogleOneStandard
+	}
+	if storageBytes >= StorageTierBasic {
+		return TierGoogleOneBasic
+	}
+	if storageBytes >= StorageTierFree {
+		return TierFree
+	}
+	return TierGoogleOneUnknown
+}
+
+// fetchGoogleOneTier fetches Google One tier from Drive API
+func (s *GeminiOAuthService) FetchGoogleOneTier(ctx context.Context, accessToken, proxyURL string) (string, *geminicli.DriveStorageInfo, error) {
+	driveClient := geminicli.NewDriveClient()
+
+	storageInfo, err := driveClient.GetStorageQuota(ctx, accessToken, proxyURL)
+	if err != nil {
+		// Check if it's a 403 (scope not granted)
+		if strings.Contains(err.Error(), "status 403") {
+			fmt.Printf("[GeminiOAuth] Drive API scope not available: %v\n", err)
+			return TierGoogleOneUnknown, nil, err
+		}
+		// Other errors
+		fmt.Printf("[GeminiOAuth] Failed to fetch Drive storage: %v\n", err)
+		return TierGoogleOneUnknown, nil, err
+	}
+
+	tierID := inferGoogleOneTier(storageInfo.Limit)
+	return tierID, storageInfo, nil
+}
+
+// RefreshAccountGoogleOneTier 刷新单个账号的 Google One Tier
+func (s *GeminiOAuthService) RefreshAccountGoogleOneTier(
+	ctx context.Context,
+	account *Account,
+) (tierID string, extra map[string]any, credentials map[string]any, err error) {
+	if account == nil {
+		return "", nil, nil, fmt.Errorf("account is nil")
+	}
+
+	// 验证账号类型
+	oauthType, ok := account.Credentials["oauth_type"].(string)
+	if !ok || oauthType != "google_one" {
+		return "", nil, nil, fmt.Errorf("not a google_one OAuth account")
+	}
+
+	// 获取 access_token
+	accessToken, ok := account.Credentials["access_token"].(string)
+	if !ok || accessToken == "" {
+		return "", nil, nil, fmt.Errorf("missing access_token")
+	}
+
+	// 获取 proxy URL
+	var proxyURL string
+	if account.ProxyID != nil && account.Proxy != nil {
+		proxyURL = account.Proxy.URL()
+	}
+
+	// 调用 Drive API
+	tierID, storageInfo, err := s.FetchGoogleOneTier(ctx, accessToken, proxyURL)
+	if err != nil {
+		return "", nil, nil, err
+	}
+
+	// 构建 extra 数据（保留原有 extra 字段）
+	extra = make(map[string]any)
+	for k, v := range account.Extra {
+		extra[k] = v
+	}
+	if storageInfo != nil {
+		extra["drive_storage_limit"] = storageInfo.Limit
+		extra["drive_storage_usage"] = storageInfo.Usage
+		extra["drive_tier_updated_at"] = time.Now().Format(time.RFC3339)
+	}
+
+	// 构建 credentials 数据
+	credentials = make(map[string]any)
+	for k, v := range account.Credentials {
+		credentials[k] = v
+	}
+	credentials["tier_id"] = tierID
+
+	return tierID, extra, credentials, nil
 }
 
 func (s *GeminiOAuthService) ExchangeCode(ctx context.Context, input *GeminiExchangeCodeInput) (*GeminiTokenInfo, error) {
@@ -219,26 +379,78 @@ func (s *GeminiOAuthService) ExchangeCode(ctx context.Context, input *GeminiExch
 	sessionProjectID := strings.TrimSpace(session.ProjectID)
 	s.sessionStore.Delete(input.SessionID)
 
-	// 计算过期时间时减去 5 分钟安全时间窗口,考虑网络延迟和时钟偏差
-	expiresAt := time.Now().Unix() + tokenResp.ExpiresIn - 300
+	// 计算过期时间：减去 5 分钟安全时间窗口（考虑网络延迟和时钟偏差）
+	// 同时设置下界保护，防止 expires_in 过小导致过去时间（引发刷新风暴）
+	const safetyWindow = 300 // 5 minutes
+	const minTTL = 30        // minimum 30 seconds
+	expiresAt := time.Now().Unix() + tokenResp.ExpiresIn - safetyWindow
+	minExpiresAt := time.Now().Unix() + minTTL
+	if expiresAt < minExpiresAt {
+		expiresAt = minExpiresAt
+	}
 
 	projectID := sessionProjectID
+	var tierID string
 
-	// 对于 code_assist 模式，project_id 是必需的
+	// 对于 code_assist 模式，project_id 是必需的，需要调用 Code Assist API
+	// 对于 google_one 模式，使用个人 Google 账号，不需要 project_id，配额由 Google 网关自动识别
 	// 对于 ai_studio 模式，project_id 是可选的（不影响使用 AI Studio API）
-	if oauthType == "code_assist" {
+	switch oauthType {
+	case "code_assist":
 		if projectID == "" {
 			var err error
-			projectID, err = s.fetchProjectID(ctx, tokenResp.AccessToken, proxyURL)
+			projectID, tierID, err = s.fetchProjectID(ctx, tokenResp.AccessToken, proxyURL)
 			if err != nil {
 				// 记录警告但不阻断流程，允许后续补充 project_id
 				fmt.Printf("[GeminiOAuth] Warning: Failed to fetch project_id during token exchange: %v\n", err)
 			}
+		} else {
+			// 用户手动填了 project_id，仍需调用 LoadCodeAssist 获取 tierID
+			_, fetchedTierID, err := s.fetchProjectID(ctx, tokenResp.AccessToken, proxyURL)
+			if err != nil {
+				fmt.Printf("[GeminiOAuth] Warning: Failed to fetch tierID: %v\n", err)
+			} else {
+				tierID = fetchedTierID
+			}
 		}
 		if strings.TrimSpace(projectID) == "" {
 			return nil, fmt.Errorf("missing project_id for Code Assist OAuth: please fill Project ID (optional field) and regenerate the auth URL, or ensure your Google account has an ACTIVE GCP project")
 		}
+		// tierID 缺失时使用默认值
+		if tierID == "" {
+			tierID = "LEGACY"
+		}
+	case "google_one":
+		// Attempt to fetch Drive storage tier
+		tierID, storageInfo, err := s.FetchGoogleOneTier(ctx, tokenResp.AccessToken, proxyURL)
+		if err != nil {
+			// Log warning but don't block - use fallback
+			fmt.Printf("[GeminiOAuth] Warning: Failed to fetch Drive tier: %v\n", err)
+			tierID = TierGoogleOneUnknown
+		}
+
+		// Store Drive info in extra field for caching
+		if storageInfo != nil {
+			tokenInfo := &GeminiTokenInfo{
+				AccessToken:  tokenResp.AccessToken,
+				RefreshToken: tokenResp.RefreshToken,
+				TokenType:    tokenResp.TokenType,
+				ExpiresIn:    tokenResp.ExpiresIn,
+				ExpiresAt:    expiresAt,
+				Scope:        tokenResp.Scope,
+				ProjectID:    projectID,
+				TierID:       tierID,
+				OAuthType:    oauthType,
+				Extra: map[string]any{
+					"drive_storage_limit":   storageInfo.Limit,
+					"drive_storage_usage":   storageInfo.Usage,
+					"drive_tier_updated_at": time.Now().Format(time.RFC3339),
+				},
+			}
+			return tokenInfo, nil
+		}
 	}
+	// ai_studio 模式不设置 tierID，保持为空
 
 	return &GeminiTokenInfo{
 		AccessToken:  tokenResp.AccessToken,
@@ -248,6 +460,7 @@ func (s *GeminiOAuthService) ExchangeCode(ctx context.Context, input *GeminiExch
 		ExpiresAt:    expiresAt,
 		Scope:        tokenResp.Scope,
 		ProjectID:    projectID,
+		TierID:       tierID,
 		OAuthType:    oauthType,
 	}, nil
 }
@@ -266,8 +479,15 @@ func (s *GeminiOAuthService) RefreshToken(ctx context.Context, oauthType, refres
 
 		tokenResp, err := s.oauthClient.RefreshToken(ctx, oauthType, refreshToken, proxyURL)
 		if err == nil {
-			// 计算过期时间时减去 5 分钟安全时间窗口,考虑网络延迟和时钟偏差
-			expiresAt := time.Now().Unix() + tokenResp.ExpiresIn - 300
+			// 计算过期时间：减去 5 分钟安全时间窗口（考虑网络延迟和时钟偏差）
+			// 同时设置下界保护，防止 expires_in 过小导致过去时间（引发刷新风暴）
+			const safetyWindow = 300 // 5 minutes
+			const minTTL = 30        // minimum 30 seconds
+			expiresAt := time.Now().Unix() + tokenResp.ExpiresIn - safetyWindow
+			minExpiresAt := time.Now().Unix() + minTTL
+			if expiresAt < minExpiresAt {
+				expiresAt = minExpiresAt
+			}
 			return &GeminiTokenInfo{
 				AccessToken:  tokenResp.AccessToken,
 				RefreshToken: tokenResp.RefreshToken,
@@ -354,18 +574,75 @@ func (s *GeminiOAuthService) RefreshAccountToken(ctx context.Context, account *A
 		tokenInfo.ProjectID = existingProjectID
 	}
 
+	// 尝试从账号凭证获取 tierID（向后兼容）
+	existingTierID := strings.TrimSpace(account.GetCredential("tier_id"))
+
 	// For Code Assist, project_id is required. Auto-detect if missing.
 	// For AI Studio OAuth, project_id is optional and should not block refresh.
-	if oauthType == "code_assist" && strings.TrimSpace(tokenInfo.ProjectID) == "" {
-		projectID, err := s.fetchProjectID(ctx, tokenInfo.AccessToken, proxyURL)
+	switch oauthType {
+	case "code_assist":
+		// 先设置默认值或保留旧值，确保 tier_id 始终有值
+		if existingTierID != "" {
+			tokenInfo.TierID = existingTierID
+		} else {
+			tokenInfo.TierID = "LEGACY" // 默认值
+		}
+
+		// 尝试自动探测 project_id 和 tier_id
+		needDetect := strings.TrimSpace(tokenInfo.ProjectID) == "" || existingTierID == ""
+		if needDetect {
+			projectID, tierID, err := s.fetchProjectID(ctx, tokenInfo.AccessToken, proxyURL)
 			if err != nil {
-			return nil, fmt.Errorf("failed to auto-detect project_id: %w", err)
+				fmt.Printf("[GeminiOAuth] Warning: failed to auto-detect project/tier: %v\n", err)
+			} else {
+				if strings.TrimSpace(tokenInfo.ProjectID) == "" && projectID != "" {
+					tokenInfo.ProjectID = projectID
 				}
-		projectID = strings.TrimSpace(projectID)
-		if projectID == "" {
+				// 只有当原来没有 tier_id 且探测成功时才更新
+				if existingTierID == "" && tierID != "" {
+					tokenInfo.TierID = tierID
+				}
+			}
+		}
+
+		if strings.TrimSpace(tokenInfo.ProjectID) == "" {
 			return nil, fmt.Errorf("failed to auto-detect project_id: empty result")
 		}
-		tokenInfo.ProjectID = projectID
+	case "google_one":
+		// Check if tier cache is stale (> 24 hours)
+		needsRefresh := true
+		if account.Extra != nil {
+			if updatedAtStr, ok := account.Extra["drive_tier_updated_at"].(string); ok {
+				if updatedAt, err := time.Parse(time.RFC3339, updatedAtStr); err == nil {
+					if time.Since(updatedAt) <= 24*time.Hour {
+						needsRefresh = false
+						// Use cached tier
+						if existingTierID != "" {
+							tokenInfo.TierID = existingTierID
+						}
+					}
+				}
+			}
+		}
+
+		if needsRefresh {
+			tierID, storageInfo, err := s.FetchGoogleOneTier(ctx, tokenInfo.AccessToken, proxyURL)
+			if err == nil && storageInfo != nil {
+				tokenInfo.TierID = tierID
+				tokenInfo.Extra = map[string]any{
+					"drive_storage_limit":   storageInfo.Limit,
+					"drive_storage_usage":   storageInfo.Usage,
+					"drive_tier_updated_at": time.Now().Format(time.RFC3339),
+				}
+			} else {
+				// Fallback to cached or unknown
+				if existingTierID != "" {
+					tokenInfo.TierID = existingTierID
+				} else {
+					tokenInfo.TierID = TierGoogleOneUnknown
+				}
+			}
+		}
 	}
 
 	return tokenInfo, nil
@@ -388,9 +665,22 @@ func (s *GeminiOAuthService) BuildAccountCredentials(tokenInfo *GeminiTokenInfo)
 	if tokenInfo.ProjectID != "" {
 		creds["project_id"] = tokenInfo.ProjectID
 	}
+	if tokenInfo.TierID != "" {
+		// Validate tier_id before storing
+		if err := validateTierID(tokenInfo.TierID); err == nil {
+			creds["tier_id"] = tokenInfo.TierID
+		}
+		// Silently skip invalid tier_id (don't block account creation)
+	}
 	if tokenInfo.OAuthType != "" {
 		creds["oauth_type"] = tokenInfo.OAuthType
 	}
+	// Store extra metadata (Drive info) if present
+	if len(tokenInfo.Extra) > 0 {
+		for k, v := range tokenInfo.Extra {
+			creds[k] = v
+		}
+	}
 	return creds
 }
 
@@ -398,33 +688,22 @@ func (s *GeminiOAuthService) Stop() {
 	s.sessionStore.Stop()
 }
 
-func (s *GeminiOAuthService) fetchProjectID(ctx context.Context, accessToken, proxyURL string) (string, error) {
+func (s *GeminiOAuthService) fetchProjectID(ctx context.Context, accessToken, proxyURL string) (string, string, error) {
 	if s.codeAssist == nil {
-		return "", errors.New("code assist client not configured")
+		return "", "", errors.New("code assist client not configured")
 	}
 
 	loadResp, loadErr := s.codeAssist.LoadCodeAssist(ctx, accessToken, proxyURL, nil)
-	if loadErr == nil && loadResp != nil && strings.TrimSpace(loadResp.CloudAICompanionProject) != "" {
-		return strings.TrimSpace(loadResp.CloudAICompanionProject), nil
-	}
 
-	// Pick tier from allowedTiers; if no default tier is marked, pick the first non-empty tier ID.
+	// Extract tierID from response (works whether CloudAICompanionProject is set or not)
 	tierID := "LEGACY"
 	if loadResp != nil {
-		for _, tier := range loadResp.AllowedTiers {
-			if tier.IsDefault && strings.TrimSpace(tier.ID) != "" {
-				tierID = strings.TrimSpace(tier.ID)
-				break
-			}
-		}
-		if strings.TrimSpace(tierID) == "" || tierID == "LEGACY" {
-			for _, tier := range loadResp.AllowedTiers {
-				if strings.TrimSpace(tier.ID) != "" {
-					tierID = strings.TrimSpace(tier.ID)
-					break
-				}
-			}
+		tierID = extractTierIDFromAllowedTiers(loadResp.AllowedTiers)
 	}
+
+	// If LoadCodeAssist returned a project, use it
+	if loadErr == nil && loadResp != nil && strings.TrimSpace(loadResp.CloudAICompanionProject) != "" {
+		return strings.TrimSpace(loadResp.CloudAICompanionProject), tierID, nil
 	}
 
 	req := &geminicli.OnboardUserRequest{
@@ -443,39 +722,39 @@ func (s *GeminiOAuthService) fetchProjectID(ctx context.Context, accessToken, pr
 			// If Code Assist onboarding fails (e.g. INVALID_ARGUMENT), fallback to Cloud Resource Manager projects.
 			fallback, fbErr := fetchProjectIDFromResourceManager(ctx, accessToken, proxyURL)
 			if fbErr == nil && strings.TrimSpace(fallback) != "" {
-				return strings.TrimSpace(fallback), nil
+				return strings.TrimSpace(fallback), tierID, nil
 			}
-			return "", err
+			return "", tierID, err
 		}
 		if resp.Done {
 			if resp.Response != nil && resp.Response.CloudAICompanionProject != nil {
 				switch v := resp.Response.CloudAICompanionProject.(type) {
 				case string:
-					return strings.TrimSpace(v), nil
+					return strings.TrimSpace(v), tierID, nil
 				case map[string]any:
 					if id, ok := v["id"].(string); ok {
-						return strings.TrimSpace(id), nil
+						return strings.TrimSpace(id), tierID, nil
 					}
 				}
 			}
 
 			fallback, fbErr := fetchProjectIDFromResourceManager(ctx, accessToken, proxyURL)
 			if fbErr == nil && strings.TrimSpace(fallback) != "" {
-				return strings.TrimSpace(fallback), nil
+				return strings.TrimSpace(fallback), tierID, nil
 			}
-			return "", errors.New("onboardUser completed but no project_id returned")
+			return "", tierID, errors.New("onboardUser completed but no project_id returned")
 		}
 		time.Sleep(2 * time.Second)
 	}
 
 	fallback, fbErr := fetchProjectIDFromResourceManager(ctx, accessToken, proxyURL)
 	if fbErr == nil && strings.TrimSpace(fallback) != "" {
-		return strings.TrimSpace(fallback), nil
+		return strings.TrimSpace(fallback), tierID, nil
 	}
 	if loadErr != nil {
-		return "", fmt.Errorf("loadCodeAssist failed (%v) and onboardUser timeout after %d attempts", loadErr, maxAttempts)
+		return "", tierID, fmt.Errorf("loadCodeAssist failed (%v) and onboardUser timeout after %d attempts", loadErr, maxAttempts)
 	}
-	return "", fmt.Errorf("onboardUser timeout after %d attempts", maxAttempts)
+	return "", tierID, fmt.Errorf("onboardUser timeout after %d attempts", maxAttempts)
 }
 
 type googleCloudProject struct {

backend/internal/service/gemini_oauth_service_test.go

+package service
+
+import "testing"
+
+func TestInferGoogleOneTier(t *testing.T) {
+	tests := []struct {
+		name         string
+		storageBytes int64
+		expectedTier string
+	}{
+		{"Negative storage", -1, TierGoogleOneUnknown},
+		{"Zero storage", 0, TierGoogleOneUnknown},
+
+		// Free tier boundary (15GB)
+		{"Below free tier", 10 * GB, TierGoogleOneUnknown},
+		{"Just below free tier", StorageTierFree - 1, TierGoogleOneUnknown},
+		{"Free tier (15GB)", StorageTierFree, TierFree},
+
+		// Basic tier boundary (100GB)
+		{"Between free and basic", 50 * GB, TierFree},
+		{"Just below basic tier", StorageTierBasic - 1, TierFree},
+		{"Basic tier (100GB)", StorageTierBasic, TierGoogleOneBasic},
+
+		// Standard tier boundary (200GB)
+		{"Between basic and standard", 150 * GB, TierGoogleOneBasic},
+		{"Just below standard tier", StorageTierStandard - 1, TierGoogleOneBasic},
+		{"Standard tier (200GB)", StorageTierStandard, TierGoogleOneStandard},
+
+		// AI Premium tier boundary (2TB)
+		{"Between standard and premium", 1 * TB, TierGoogleOneStandard},
+		{"Just below AI Premium tier", StorageTierAIPremium - 1, TierGoogleOneStandard},
+		{"AI Premium tier (2TB)", StorageTierAIPremium, TierAIPremium},
+
+		// Unlimited tier boundary (> 100TB)
+		{"Between premium and unlimited", 50 * TB, TierAIPremium},
+		{"At unlimited threshold (100TB)", StorageTierUnlimited, TierAIPremium},
+		{"Unlimited tier (100TB+)", StorageTierUnlimited + 1, TierGoogleOneUnlimited},
+		{"Unlimited tier (101TB+)", 101 * TB, TierGoogleOneUnlimited},
+		{"Very large storage", 1000 * TB, TierGoogleOneUnlimited},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := inferGoogleOneTier(tt.storageBytes)
+			if result != tt.expectedTier {
+				t.Errorf("inferGoogleOneTier(%d) = %s, want %s",
+					tt.storageBytes, result, tt.expectedTier)
+			}
+		})
+	}
+}

backend/internal/service/gemini_quota.go

+package service
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"log"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/usagestats"
+)
+
+type geminiModelClass string
+
+const (
+	geminiModelPro   geminiModelClass = "pro"
+	geminiModelFlash geminiModelClass = "flash"
+)
+
+type GeminiDailyQuota struct {
+	ProRPD   int64
+	FlashRPD int64
+}
+
+type GeminiTierPolicy struct {
+	Quota    GeminiDailyQuota
+	Cooldown time.Duration
+}
+
+type GeminiQuotaPolicy struct {
+	tiers map[string]GeminiTierPolicy
+}
+
+type GeminiUsageTotals struct {
+	ProRequests   int64
+	FlashRequests int64
+	ProTokens     int64
+	FlashTokens   int64
+	ProCost       float64
+	FlashCost     float64
+}
+
+const geminiQuotaCacheTTL = time.Minute
+
+type geminiQuotaOverrides struct {
+	Tiers map[string]config.GeminiTierQuotaConfig `json:"tiers"`
+}
+
+type GeminiQuotaService struct {
+	cfg         *config.Config
+	settingRepo SettingRepository
+	mu          sync.Mutex
+	cachedAt    time.Time
+	policy      *GeminiQuotaPolicy
+}
+
+func NewGeminiQuotaService(cfg *config.Config, settingRepo SettingRepository) *GeminiQuotaService {
+	return &GeminiQuotaService{
+		cfg:         cfg,
+		settingRepo: settingRepo,
+	}
+}
+
+func (s *GeminiQuotaService) Policy(ctx context.Context) *GeminiQuotaPolicy {
+	if s == nil {
+		return newGeminiQuotaPolicy()
+	}
+
+	now := time.Now()
+	s.mu.Lock()
+	if s.policy != nil && now.Sub(s.cachedAt) < geminiQuotaCacheTTL {
+		policy := s.policy
+		s.mu.Unlock()
+		return policy
+	}
+	s.mu.Unlock()
+
+	policy := newGeminiQuotaPolicy()
+	if s.cfg != nil {
+		policy.ApplyOverrides(s.cfg.Gemini.Quota.Tiers)
+		if strings.TrimSpace(s.cfg.Gemini.Quota.Policy) != "" {
+			var overrides geminiQuotaOverrides
+			if err := json.Unmarshal([]byte(s.cfg.Gemini.Quota.Policy), &overrides); err != nil {
+				log.Printf("gemini quota: parse config policy failed: %v", err)
+			} else {
+				policy.ApplyOverrides(overrides.Tiers)
+			}
+		}
+	}
+
+	if s.settingRepo != nil {
+		value, err := s.settingRepo.GetValue(ctx, SettingKeyGeminiQuotaPolicy)
+		if err != nil && !errors.Is(err, ErrSettingNotFound) {
+			log.Printf("gemini quota: load setting failed: %v", err)
+		} else if strings.TrimSpace(value) != "" {
+			var overrides geminiQuotaOverrides
+			if err := json.Unmarshal([]byte(value), &overrides); err != nil {
+				log.Printf("gemini quota: parse setting failed: %v", err)
+			} else {
+				policy.ApplyOverrides(overrides.Tiers)
+			}
+		}
+	}
+
+	s.mu.Lock()
+	s.policy = policy
+	s.cachedAt = now
+	s.mu.Unlock()
+
+	return policy
+}
+
+func (s *GeminiQuotaService) QuotaForAccount(ctx context.Context, account *Account) (GeminiDailyQuota, bool) {
+	if account == nil || !account.IsGeminiCodeAssist() {
+		return GeminiDailyQuota{}, false
+	}
+	policy := s.Policy(ctx)
+	return policy.QuotaForTier(account.GeminiTierID())
+}
+
+func (s *GeminiQuotaService) CooldownForTier(ctx context.Context, tierID string) time.Duration {
+	policy := s.Policy(ctx)
+	return policy.CooldownForTier(tierID)
+}
+
+func newGeminiQuotaPolicy() *GeminiQuotaPolicy {
+	return &GeminiQuotaPolicy{
+		tiers: map[string]GeminiTierPolicy{
+			"LEGACY": {Quota: GeminiDailyQuota{ProRPD: 50, FlashRPD: 1500}, Cooldown: 30 * time.Minute},
+			"PRO":    {Quota: GeminiDailyQuota{ProRPD: 1500, FlashRPD: 4000}, Cooldown: 5 * time.Minute},
+			"ULTRA":  {Quota: GeminiDailyQuota{ProRPD: 2000, FlashRPD: 0}, Cooldown: 5 * time.Minute},
+		},
+	}
+}
+
+func (p *GeminiQuotaPolicy) ApplyOverrides(tiers map[string]config.GeminiTierQuotaConfig) {
+	if p == nil || len(tiers) == 0 {
+		return
+	}
+	for rawID, override := range tiers {
+		tierID := normalizeGeminiTierID(rawID)
+		if tierID == "" {
+			continue
+		}
+		policy, ok := p.tiers[tierID]
+		if !ok {
+			policy = GeminiTierPolicy{Cooldown: 5 * time.Minute}
+		}
+		if override.ProRPD != nil {
+			policy.Quota.ProRPD = clampGeminiQuotaInt64(*override.ProRPD)
+		}
+		if override.FlashRPD != nil {
+			policy.Quota.FlashRPD = clampGeminiQuotaInt64(*override.FlashRPD)
+		}
+		if override.CooldownMinutes != nil {
+			minutes := clampGeminiQuotaInt(*override.CooldownMinutes)
+			policy.Cooldown = time.Duration(minutes) * time.Minute
+		}
+		p.tiers[tierID] = policy
+	}
+}
+
+func (p *GeminiQuotaPolicy) QuotaForTier(tierID string) (GeminiDailyQuota, bool) {
+	policy, ok := p.policyForTier(tierID)
+	if !ok {
+		return GeminiDailyQuota{}, false
+	}
+	return policy.Quota, true
+}
+
+func (p *GeminiQuotaPolicy) CooldownForTier(tierID string) time.Duration {
+	policy, ok := p.policyForTier(tierID)
+	if ok && policy.Cooldown > 0 {
+		return policy.Cooldown
+	}
+	return 5 * time.Minute
+}
+
+func (p *GeminiQuotaPolicy) policyForTier(tierID string) (GeminiTierPolicy, bool) {
+	if p == nil {
+		return GeminiTierPolicy{}, false
+	}
+	normalized := normalizeGeminiTierID(tierID)
+	if normalized == "" {
+		normalized = "LEGACY"
+	}
+	if policy, ok := p.tiers[normalized]; ok {
+		return policy, true
+	}
+	policy, ok := p.tiers["LEGACY"]
+	return policy, ok
+}
+
+func normalizeGeminiTierID(tierID string) string {
+	return strings.ToUpper(strings.TrimSpace(tierID))
+}
+
+func clampGeminiQuotaInt64(value int64) int64 {
+	if value < 0 {
+		return 0
+	}
+	return value
+}
+
+func clampGeminiQuotaInt(value int) int {
+	if value < 0 {
+		return 0
+	}
+	return value
+}
+
+func geminiCooldownForTier(tierID string) time.Duration {
+	policy := newGeminiQuotaPolicy()
+	return policy.CooldownForTier(tierID)
+}
+
+func geminiModelClassFromName(model string) geminiModelClass {
+	name := strings.ToLower(strings.TrimSpace(model))
+	if strings.Contains(name, "flash") || strings.Contains(name, "lite") {
+		return geminiModelFlash
+	}
+	return geminiModelPro
+}
+
+func geminiAggregateUsage(stats []usagestats.ModelStat) GeminiUsageTotals {
+	var totals GeminiUsageTotals
+	for _, stat := range stats {
+		switch geminiModelClassFromName(stat.Model) {
+		case geminiModelFlash:
+			totals.FlashRequests += stat.Requests
+			totals.FlashTokens += stat.TotalTokens
+			totals.FlashCost += stat.ActualCost
+		default:
+			totals.ProRequests += stat.Requests
+			totals.ProTokens += stat.TotalTokens
+			totals.ProCost += stat.ActualCost
+		}
+	}
+	return totals
+}
+
+func geminiQuotaLocation() *time.Location {
+	loc, err := time.LoadLocation("America/Los_Angeles")
+	if err != nil {
+		return time.FixedZone("PST", -8*3600)
+	}
+	return loc
+}
+
+func geminiDailyWindowStart(now time.Time) time.Time {
+	loc := geminiQuotaLocation()
+	localNow := now.In(loc)
+	return time.Date(localNow.Year(), localNow.Month(), localNow.Day(), 0, 0, 0, 0, loc)
+}
+
+func geminiDailyResetTime(now time.Time) time.Time {
+	loc := geminiQuotaLocation()
+	localNow := now.In(loc)
+	start := time.Date(localNow.Year(), localNow.Month(), localNow.Day(), 0, 0, 0, 0, loc)
+	reset := start.Add(24 * time.Hour)
+	if !reset.After(localNow) {
+		reset = reset.Add(24 * time.Hour)
+	}
+	return reset
+}

backend/internal/service/gemini_token_provider.go

@@ -112,17 +112,21 @@ func (p *GeminiTokenProvider) GetAccessToken(ctx context.Context, account *Accou
 			}
 		}
 
-		detected, err := p.geminiOAuthService.fetchProjectID(ctx, accessToken, proxyURL)
+		detected, tierID, err := p.geminiOAuthService.fetchProjectID(ctx, accessToken, proxyURL)
 		if err != nil {
 			log.Printf("[GeminiTokenProvider] Auto-detect project_id failed: %v, fallback to AI Studio API mode", err)
 			return accessToken, nil
 		}
 		detected = strings.TrimSpace(detected)
+		tierID = strings.TrimSpace(tierID)
 		if detected != "" {
 			if account.Credentials == nil {
 				account.Credentials = make(map[string]any)
 			}
 			account.Credentials["project_id"] = detected
+			if tierID != "" {
+				account.Credentials["tier_id"] = tierID
+			}
 			_ = p.accountRepo.Update(ctx, account)
 		}
 	}

backend/internal/service/openai_gateway_service.go

@@ -13,6 +13,7 @@ import (
 	"log"
 	"net/http"
 	"regexp"
+	"sort"
 	"strconv"
 	"strings"
 	"time"
@@ -80,6 +81,7 @@ type OpenAIGatewayService struct {
 	userSubRepo         UserSubscriptionRepository
 	cache               GatewayCache
 	cfg                 *config.Config
+	concurrencyService  *ConcurrencyService
 	billingService      *BillingService
 	rateLimitService    *RateLimitService
 	billingCacheService *BillingCacheService
@@ -95,6 +97,7 @@ func NewOpenAIGatewayService(
 	userSubRepo UserSubscriptionRepository,
 	cache GatewayCache,
 	cfg *config.Config,
+	concurrencyService *ConcurrencyService,
 	billingService *BillingService,
 	rateLimitService *RateLimitService,
 	billingCacheService *BillingCacheService,
@@ -108,6 +111,7 @@ func NewOpenAIGatewayService(
 		userSubRepo:         userSubRepo,
 		cache:               cache,
 		cfg:                 cfg,
+		concurrencyService:  concurrencyService,
 		billingService:      billingService,
 		rateLimitService:    rateLimitService,
 		billingCacheService: billingCacheService,
@@ -126,6 +130,14 @@ func (s *OpenAIGatewayService) GenerateSessionHash(c *gin.Context) string {
 	return hex.EncodeToString(hash[:])
 }
 
+// BindStickySession sets session -> account binding with standard TTL.
+func (s *OpenAIGatewayService) BindStickySession(ctx context.Context, sessionHash string, accountID int64) error {
+	if sessionHash == "" || accountID <= 0 {
+		return nil
+	}
+	return s.cache.SetSessionAccountID(ctx, "openai:"+sessionHash, accountID, openaiStickySessionTTL)
+}
+
 // SelectAccount selects an OpenAI account with sticky session support
 func (s *OpenAIGatewayService) SelectAccount(ctx context.Context, groupID *int64, sessionHash string) (*Account, error) {
 	return s.SelectAccountForModel(ctx, groupID, sessionHash, "")
@@ -218,6 +230,254 @@ func (s *OpenAIGatewayService) SelectAccountForModelWithExclusions(ctx context.C
 	return selected, nil
 }
 
+// SelectAccountWithLoadAwareness selects an account with load-awareness and wait plan.
+func (s *OpenAIGatewayService) SelectAccountWithLoadAwareness(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}) (*AccountSelectionResult, error) {
+	cfg := s.schedulingConfig()
+	var stickyAccountID int64
+	if sessionHash != "" && s.cache != nil {
+		if accountID, err := s.cache.GetSessionAccountID(ctx, "openai:"+sessionHash); err == nil {
+			stickyAccountID = accountID
+		}
+	}
+	if s.concurrencyService == nil || !cfg.LoadBatchEnabled {
+		account, err := s.SelectAccountForModelWithExclusions(ctx, groupID, sessionHash, requestedModel, excludedIDs)
+		if err != nil {
+			return nil, err
+		}
+		result, err := s.tryAcquireAccountSlot(ctx, account.ID, account.Concurrency)
+		if err == nil && result.Acquired {
+			return &AccountSelectionResult{
+				Account:     account,
+				Acquired:    true,
+				ReleaseFunc: result.ReleaseFunc,
+			}, nil
+		}
+		if stickyAccountID > 0 && stickyAccountID == account.ID && s.concurrencyService != nil {
+			waitingCount, _ := s.concurrencyService.GetAccountWaitingCount(ctx, account.ID)
+			if waitingCount < cfg.StickySessionMaxWaiting {
+				return &AccountSelectionResult{
+					Account: account,
+					WaitPlan: &AccountWaitPlan{
+						AccountID:      account.ID,
+						MaxConcurrency: account.Concurrency,
+						Timeout:        cfg.StickySessionWaitTimeout,
+						MaxWaiting:     cfg.StickySessionMaxWaiting,
+					},
+				}, nil
+			}
+		}
+		return &AccountSelectionResult{
+			Account: account,
+			WaitPlan: &AccountWaitPlan{
+				AccountID:      account.ID,
+				MaxConcurrency: account.Concurrency,
+				Timeout:        cfg.FallbackWaitTimeout,
+				MaxWaiting:     cfg.FallbackMaxWaiting,
+			},
+		}, nil
+	}
+
+	accounts, err := s.listSchedulableAccounts(ctx, groupID)
+	if err != nil {
+		return nil, err
+	}
+	if len(accounts) == 0 {
+		return nil, errors.New("no available accounts")
+	}
+
+	isExcluded := func(accountID int64) bool {
+		if excludedIDs == nil {
+			return false
+		}
+		_, excluded := excludedIDs[accountID]
+		return excluded
+	}
+
+	// ============ Layer 1: Sticky session ============
+	if sessionHash != "" {
+		accountID, err := s.cache.GetSessionAccountID(ctx, "openai:"+sessionHash)
+		if err == nil && accountID > 0 && !isExcluded(accountID) {
+			account, err := s.accountRepo.GetByID(ctx, accountID)
+			if err == nil && account.IsSchedulable() && account.IsOpenAI() &&
+				(requestedModel == "" || account.IsModelSupported(requestedModel)) {
+				result, err := s.tryAcquireAccountSlot(ctx, accountID, account.Concurrency)
+				if err == nil && result.Acquired {
+					_ = s.cache.RefreshSessionTTL(ctx, "openai:"+sessionHash, openaiStickySessionTTL)
+					return &AccountSelectionResult{
+						Account:     account,
+						Acquired:    true,
+						ReleaseFunc: result.ReleaseFunc,
+					}, nil
+				}
+
+				waitingCount, _ := s.concurrencyService.GetAccountWaitingCount(ctx, accountID)
+				if waitingCount < cfg.StickySessionMaxWaiting {
+					return &AccountSelectionResult{
+						Account: account,
+						WaitPlan: &AccountWaitPlan{
+							AccountID:      accountID,
+							MaxConcurrency: account.Concurrency,
+							Timeout:        cfg.StickySessionWaitTimeout,
+							MaxWaiting:     cfg.StickySessionMaxWaiting,
+						},
+					}, nil
+				}
+			}
+		}
+	}
+
+	// ============ Layer 2: Load-aware selection ============
+	candidates := make([]*Account, 0, len(accounts))
+	for i := range accounts {
+		acc := &accounts[i]
+		if isExcluded(acc.ID) {
+			continue
+		}
+		if requestedModel != "" && !acc.IsModelSupported(requestedModel) {
+			continue
+		}
+		candidates = append(candidates, acc)
+	}
+
+	if len(candidates) == 0 {
+		return nil, errors.New("no available accounts")
+	}
+
+	accountLoads := make([]AccountWithConcurrency, 0, len(candidates))
+	for _, acc := range candidates {
+		accountLoads = append(accountLoads, AccountWithConcurrency{
+			ID:             acc.ID,
+			MaxConcurrency: acc.Concurrency,
+		})
+	}
+
+	loadMap, err := s.concurrencyService.GetAccountsLoadBatch(ctx, accountLoads)
+	if err != nil {
+		ordered := append([]*Account(nil), candidates...)
+		sortAccountsByPriorityAndLastUsed(ordered, false)
+		for _, acc := range ordered {
+			result, err := s.tryAcquireAccountSlot(ctx, acc.ID, acc.Concurrency)
+			if err == nil && result.Acquired {
+				if sessionHash != "" {
+					_ = s.cache.SetSessionAccountID(ctx, "openai:"+sessionHash, acc.ID, openaiStickySessionTTL)
+				}
+				return &AccountSelectionResult{
+					Account:     acc,
+					Acquired:    true,
+					ReleaseFunc: result.ReleaseFunc,
+				}, nil
+			}
+		}
+	} else {
+		type accountWithLoad struct {
+			account  *Account
+			loadInfo *AccountLoadInfo
+		}
+		var available []accountWithLoad
+		for _, acc := range candidates {
+			loadInfo := loadMap[acc.ID]
+			if loadInfo == nil {
+				loadInfo = &AccountLoadInfo{AccountID: acc.ID}
+			}
+			if loadInfo.LoadRate < 100 {
+				available = append(available, accountWithLoad{
+					account:  acc,
+					loadInfo: loadInfo,
+				})
+			}
+		}
+
+		if len(available) > 0 {
+			sort.SliceStable(available, func(i, j int) bool {
+				a, b := available[i], available[j]
+				if a.account.Priority != b.account.Priority {
+					return a.account.Priority < b.account.Priority
+				}
+				if a.loadInfo.LoadRate != b.loadInfo.LoadRate {
+					return a.loadInfo.LoadRate < b.loadInfo.LoadRate
+				}
+				switch {
+				case a.account.LastUsedAt == nil && b.account.LastUsedAt != nil:
+					return true
+				case a.account.LastUsedAt != nil && b.account.LastUsedAt == nil:
+					return false
+				case a.account.LastUsedAt == nil && b.account.LastUsedAt == nil:
+					return false
+				default:
+					return a.account.LastUsedAt.Before(*b.account.LastUsedAt)
+				}
+			})
+
+			for _, item := range available {
+				result, err := s.tryAcquireAccountSlot(ctx, item.account.ID, item.account.Concurrency)
+				if err == nil && result.Acquired {
+					if sessionHash != "" {
+						_ = s.cache.SetSessionAccountID(ctx, "openai:"+sessionHash, item.account.ID, openaiStickySessionTTL)
+					}
+					return &AccountSelectionResult{
+						Account:     item.account,
+						Acquired:    true,
+						ReleaseFunc: result.ReleaseFunc,
+					}, nil
+				}
+			}
+		}
+	}
+
+	// ============ Layer 3: Fallback wait ============
+	sortAccountsByPriorityAndLastUsed(candidates, false)
+	for _, acc := range candidates {
+		return &AccountSelectionResult{
+			Account: acc,
+			WaitPlan: &AccountWaitPlan{
+				AccountID:      acc.ID,
+				MaxConcurrency: acc.Concurrency,
+				Timeout:        cfg.FallbackWaitTimeout,
+				MaxWaiting:     cfg.FallbackMaxWaiting,
+			},
+		}, nil
+	}
+
+	return nil, errors.New("no available accounts")
+}
+
+func (s *OpenAIGatewayService) listSchedulableAccounts(ctx context.Context, groupID *int64) ([]Account, error) {
+	var accounts []Account
+	var err error
+	if s.cfg != nil && s.cfg.RunMode == config.RunModeSimple {
+		accounts, err = s.accountRepo.ListSchedulableByPlatform(ctx, PlatformOpenAI)
+	} else if groupID != nil {
+		accounts, err = s.accountRepo.ListSchedulableByGroupIDAndPlatform(ctx, *groupID, PlatformOpenAI)
+	} else {
+		accounts, err = s.accountRepo.ListSchedulableByPlatform(ctx, PlatformOpenAI)
+	}
+	if err != nil {
+		return nil, fmt.Errorf("query accounts failed: %w", err)
+	}
+	return accounts, nil
+}
+
+func (s *OpenAIGatewayService) tryAcquireAccountSlot(ctx context.Context, accountID int64, maxConcurrency int) (*AcquireResult, error) {
+	if s.concurrencyService == nil {
+		return &AcquireResult{Acquired: true, ReleaseFunc: func() {}}, nil
+	}
+	return s.concurrencyService.AcquireAccountSlot(ctx, accountID, maxConcurrency)
+}
+
+func (s *OpenAIGatewayService) schedulingConfig() config.GatewaySchedulingConfig {
+	if s.cfg != nil {
+		return s.cfg.Gateway.Scheduling
+	}
+	return config.GatewaySchedulingConfig{
+		StickySessionMaxWaiting:  3,
+		StickySessionWaitTimeout: 45 * time.Second,
+		FallbackWaitTimeout:      30 * time.Second,
+		FallbackMaxWaiting:       100,
+		LoadBatchEnabled:         true,
+		SlotCleanupInterval:      30 * time.Second,
+	}
+}
+
 // GetAccessToken gets the access token for an OpenAI account
 func (s *OpenAIGatewayService) GetAccessToken(ctx context.Context, account *Account) (string, string, error) {
 	switch account.Type {

backend/internal/service/ratelimit_service.go

@@ -5,6 +5,8 @@ import (
 	"log"
 	"net/http"
 	"strconv"
+	"strings"
+	"sync"
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
@@ -13,14 +15,29 @@ import (
 // RateLimitService 处理限流和过载状态管理
 type RateLimitService struct {
 	accountRepo        AccountRepository
+	usageRepo          UsageLogRepository
 	cfg                *config.Config
+	geminiQuotaService *GeminiQuotaService
+	usageCacheMu       sync.RWMutex
+	usageCache         map[int64]*geminiUsageCacheEntry
 }
 
+type geminiUsageCacheEntry struct {
+	windowStart time.Time
+	cachedAt    time.Time
+	totals      GeminiUsageTotals
+}
+
+const geminiPrecheckCacheTTL = time.Minute
+
 // NewRateLimitService 创建RateLimitService实例
-func NewRateLimitService(accountRepo AccountRepository, cfg *config.Config) *RateLimitService {
+func NewRateLimitService(accountRepo AccountRepository, usageRepo UsageLogRepository, cfg *config.Config, geminiQuotaService *GeminiQuotaService) *RateLimitService {
 	return &RateLimitService{
 		accountRepo:        accountRepo,
+		usageRepo:          usageRepo,
 		cfg:                cfg,
+		geminiQuotaService: geminiQuotaService,
+		usageCache:         make(map[int64]*geminiUsageCacheEntry),
 	}
 }
 
@@ -62,6 +79,106 @@ func (s *RateLimitService) HandleUpstreamError(ctx context.Context, account *Acc
 	}
 }
 
+// PreCheckUsage proactively checks local quota before dispatching a request.
+// Returns false when the account should be skipped.
+func (s *RateLimitService) PreCheckUsage(ctx context.Context, account *Account, requestedModel string) (bool, error) {
+	if account == nil || !account.IsGeminiCodeAssist() || strings.TrimSpace(requestedModel) == "" {
+		return true, nil
+	}
+	if s.usageRepo == nil || s.geminiQuotaService == nil {
+		return true, nil
+	}
+
+	quota, ok := s.geminiQuotaService.QuotaForAccount(ctx, account)
+	if !ok {
+		return true, nil
+	}
+
+	var limit int64
+	switch geminiModelClassFromName(requestedModel) {
+	case geminiModelFlash:
+		limit = quota.FlashRPD
+	default:
+		limit = quota.ProRPD
+	}
+	if limit <= 0 {
+		return true, nil
+	}
+
+	now := time.Now()
+	start := geminiDailyWindowStart(now)
+	totals, ok := s.getGeminiUsageTotals(account.ID, start, now)
+	if !ok {
+		stats, err := s.usageRepo.GetModelStatsWithFilters(ctx, start, now, 0, 0, account.ID)
+		if err != nil {
+			return true, err
+		}
+		totals = geminiAggregateUsage(stats)
+		s.setGeminiUsageTotals(account.ID, start, now, totals)
+	}
+
+	var used int64
+	switch geminiModelClassFromName(requestedModel) {
+	case geminiModelFlash:
+		used = totals.FlashRequests
+	default:
+		used = totals.ProRequests
+	}
+
+	if used >= limit {
+		resetAt := geminiDailyResetTime(now)
+		if err := s.accountRepo.SetRateLimited(ctx, account.ID, resetAt); err != nil {
+			log.Printf("SetRateLimited failed for account %d: %v", account.ID, err)
+		}
+		log.Printf("[Gemini PreCheck] Account %d reached daily quota (%d/%d), rate limited until %v", account.ID, used, limit, resetAt)
+		return false, nil
+	}
+
+	return true, nil
+}
+
+func (s *RateLimitService) getGeminiUsageTotals(accountID int64, windowStart, now time.Time) (GeminiUsageTotals, bool) {
+	s.usageCacheMu.RLock()
+	defer s.usageCacheMu.RUnlock()
+
+	if s.usageCache == nil {
+		return GeminiUsageTotals{}, false
+	}
+
+	entry, ok := s.usageCache[accountID]
+	if !ok || entry == nil {
+		return GeminiUsageTotals{}, false
+	}
+	if !entry.windowStart.Equal(windowStart) {
+		return GeminiUsageTotals{}, false
+	}
+	if now.Sub(entry.cachedAt) >= geminiPrecheckCacheTTL {
+		return GeminiUsageTotals{}, false
+	}
+	return entry.totals, true
+}
+
+func (s *RateLimitService) setGeminiUsageTotals(accountID int64, windowStart, now time.Time, totals GeminiUsageTotals) {
+	s.usageCacheMu.Lock()
+	defer s.usageCacheMu.Unlock()
+	if s.usageCache == nil {
+		s.usageCache = make(map[int64]*geminiUsageCacheEntry)
+	}
+	s.usageCache[accountID] = &geminiUsageCacheEntry{
+		windowStart: windowStart,
+		cachedAt:    now,
+		totals:      totals,
+	}
+}
+
+// GeminiCooldown returns the fallback cooldown duration for Gemini 429s based on tier.
+func (s *RateLimitService) GeminiCooldown(ctx context.Context, account *Account) time.Duration {
+	if account == nil {
+		return 5 * time.Minute
+	}
+	return s.geminiQuotaService.CooldownForTier(ctx, account.GeminiTierID())
+}
+
 // handleAuthError 处理认证类错误(401/403)，停止账号调度
 func (s *RateLimitService) handleAuthError(ctx context.Context, account *Account, errorMsg string) {
 	if err := s.accountRepo.SetError(ctx, account.ID, errorMsg); err != nil {

backend/internal/service/user.go

@@ -10,7 +10,6 @@ type User struct {
 	ID            int64
 	Email         string
 	Username      string
-	Wechat        string
 	Notes         string
 	PasswordHash  string
 	Role          string

backend/internal/service/user_attribute.go

+package service
+
+import (
+	"context"
+	"time"
+
+	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
+)
+
+// Error definitions for user attribute operations
+var (
+	ErrAttributeDefinitionNotFound = infraerrors.NotFound("ATTRIBUTE_DEFINITION_NOT_FOUND", "attribute definition not found")
+	ErrAttributeKeyExists          = infraerrors.Conflict("ATTRIBUTE_KEY_EXISTS", "attribute key already exists")
+	ErrInvalidAttributeType        = infraerrors.BadRequest("INVALID_ATTRIBUTE_TYPE", "invalid attribute type")
+	ErrAttributeValidationFailed   = infraerrors.BadRequest("ATTRIBUTE_VALIDATION_FAILED", "attribute value validation failed")
+)
+
+// UserAttributeType represents supported attribute types
+type UserAttributeType string
+
+const (
+	AttributeTypeText        UserAttributeType = "text"
+	AttributeTypeTextarea    UserAttributeType = "textarea"
+	AttributeTypeNumber      UserAttributeType = "number"
+	AttributeTypeEmail       UserAttributeType = "email"
+	AttributeTypeURL         UserAttributeType = "url"
+	AttributeTypeDate        UserAttributeType = "date"
+	AttributeTypeSelect      UserAttributeType = "select"
+	AttributeTypeMultiSelect UserAttributeType = "multi_select"
+)
+
+// UserAttributeOption represents a select option for select/multi_select types
+type UserAttributeOption struct {
+	Value string `json:"value"`
+	Label string `json:"label"`
+}
+
+// UserAttributeValidation represents validation rules for an attribute
+type UserAttributeValidation struct {
+	MinLength *int    `json:"min_length,omitempty"`
+	MaxLength *int    `json:"max_length,omitempty"`
+	Min       *int    `json:"min,omitempty"`
+	Max       *int    `json:"max,omitempty"`
+	Pattern   *string `json:"pattern,omitempty"`
+	Message   *string `json:"message,omitempty"`
+}
+
+// UserAttributeDefinition represents a custom attribute definition
+type UserAttributeDefinition struct {
+	ID           int64
+	Key          string
+	Name         string
+	Description  string
+	Type         UserAttributeType
+	Options      []UserAttributeOption
+	Required     bool
+	Validation   UserAttributeValidation
+	Placeholder  string
+	DisplayOrder int
+	Enabled      bool
+	CreatedAt    time.Time
+	UpdatedAt    time.Time
+}
+
+// UserAttributeValue represents a user's attribute value
+type UserAttributeValue struct {
+	ID          int64
+	UserID      int64
+	AttributeID int64
+	Value       string
+	CreatedAt   time.Time
+	UpdatedAt   time.Time
+}
+
+// CreateAttributeDefinitionInput for creating new definition
+type CreateAttributeDefinitionInput struct {
+	Key         string
+	Name        string
+	Description string
+	Type        UserAttributeType
+	Options     []UserAttributeOption
+	Required    bool
+	Validation  UserAttributeValidation
+	Placeholder string
+	Enabled     bool
+}
+
+// UpdateAttributeDefinitionInput for updating definition
+type UpdateAttributeDefinitionInput struct {
+	Name        *string
+	Description *string
+	Type        *UserAttributeType
+	Options     *[]UserAttributeOption
+	Required    *bool
+	Validation  *UserAttributeValidation
+	Placeholder *string
+	Enabled     *bool
+}
+
+// UpdateUserAttributeInput for updating a single attribute value
+type UpdateUserAttributeInput struct {
+	AttributeID int64
+	Value       string
+}
+
+// UserAttributeDefinitionRepository interface for attribute definition persistence
+type UserAttributeDefinitionRepository interface {
+	Create(ctx context.Context, def *UserAttributeDefinition) error
+	GetByID(ctx context.Context, id int64) (*UserAttributeDefinition, error)
+	GetByKey(ctx context.Context, key string) (*UserAttributeDefinition, error)
+	Update(ctx context.Context, def *UserAttributeDefinition) error
+	Delete(ctx context.Context, id int64) error
+	List(ctx context.Context, enabledOnly bool) ([]UserAttributeDefinition, error)
+	UpdateDisplayOrders(ctx context.Context, orders map[int64]int) error
+	ExistsByKey(ctx context.Context, key string) (bool, error)
+}
+
+// UserAttributeValueRepository interface for user attribute value persistence
+type UserAttributeValueRepository interface {
+	GetByUserID(ctx context.Context, userID int64) ([]UserAttributeValue, error)
+	GetByUserIDs(ctx context.Context, userIDs []int64) ([]UserAttributeValue, error)
+	UpsertBatch(ctx context.Context, userID int64, values []UpdateUserAttributeInput) error
+	DeleteByAttributeID(ctx context.Context, attributeID int64) error
+	DeleteByUserID(ctx context.Context, userID int64) error
+}

backend/internal/service/user_attribute_service.go

+package service
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+
+	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
+)
+
+// UserAttributeService handles attribute management
+type UserAttributeService struct {
+	defRepo   UserAttributeDefinitionRepository
+	valueRepo UserAttributeValueRepository
+}
+
+// NewUserAttributeService creates a new service instance
+func NewUserAttributeService(
+	defRepo UserAttributeDefinitionRepository,
+	valueRepo UserAttributeValueRepository,
+) *UserAttributeService {
+	return &UserAttributeService{
+		defRepo:   defRepo,
+		valueRepo: valueRepo,
+	}
+}
+
+// CreateDefinition creates a new attribute definition
+func (s *UserAttributeService) CreateDefinition(ctx context.Context, input CreateAttributeDefinitionInput) (*UserAttributeDefinition, error) {
+	// Validate type
+	if !isValidAttributeType(input.Type) {
+		return nil, ErrInvalidAttributeType
+	}
+
+	// Check if key exists
+	exists, err := s.defRepo.ExistsByKey(ctx, input.Key)
+	if err != nil {
+		return nil, fmt.Errorf("check key exists: %w", err)
+	}
+	if exists {
+		return nil, ErrAttributeKeyExists
+	}
+
+	def := &UserAttributeDefinition{
+		Key:         input.Key,
+		Name:        input.Name,
+		Description: input.Description,
+		Type:        input.Type,
+		Options:     input.Options,
+		Required:    input.Required,
+		Validation:  input.Validation,
+		Placeholder: input.Placeholder,
+		Enabled:     input.Enabled,
+	}
+
+	if err := s.defRepo.Create(ctx, def); err != nil {
+		return nil, fmt.Errorf("create definition: %w", err)
+	}
+
+	return def, nil
+}
+
+// GetDefinition retrieves a definition by ID
+func (s *UserAttributeService) GetDefinition(ctx context.Context, id int64) (*UserAttributeDefinition, error) {
+	return s.defRepo.GetByID(ctx, id)
+}
+
+// ListDefinitions lists all definitions
+func (s *UserAttributeService) ListDefinitions(ctx context.Context, enabledOnly bool) ([]UserAttributeDefinition, error) {
+	return s.defRepo.List(ctx, enabledOnly)
+}
+
+// UpdateDefinition updates an existing definition
+func (s *UserAttributeService) UpdateDefinition(ctx context.Context, id int64, input UpdateAttributeDefinitionInput) (*UserAttributeDefinition, error) {
+	def, err := s.defRepo.GetByID(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+
+	if input.Name != nil {
+		def.Name = *input.Name
+	}
+	if input.Description != nil {
+		def.Description = *input.Description
+	}
+	if input.Type != nil {
+		if !isValidAttributeType(*input.Type) {
+			return nil, ErrInvalidAttributeType
+		}
+		def.Type = *input.Type
+	}
+	if input.Options != nil {
+		def.Options = *input.Options
+	}
+	if input.Required != nil {
+		def.Required = *input.Required
+	}
+	if input.Validation != nil {
+		def.Validation = *input.Validation
+	}
+	if input.Placeholder != nil {
+		def.Placeholder = *input.Placeholder
+	}
+	if input.Enabled != nil {
+		def.Enabled = *input.Enabled
+	}
+
+	if err := s.defRepo.Update(ctx, def); err != nil {
+		return nil, fmt.Errorf("update definition: %w", err)
+	}
+
+	return def, nil
+}
+
+// DeleteDefinition soft-deletes a definition and hard-deletes associated values
+func (s *UserAttributeService) DeleteDefinition(ctx context.Context, id int64) error {
+	// Check if definition exists
+	_, err := s.defRepo.GetByID(ctx, id)
+	if err != nil {
+		return err
+	}
+
+	// First delete all values (hard delete)
+	if err := s.valueRepo.DeleteByAttributeID(ctx, id); err != nil {
+		return fmt.Errorf("delete values: %w", err)
+	}
+
+	// Then soft-delete the definition
+	if err := s.defRepo.Delete(ctx, id); err != nil {
+		return fmt.Errorf("delete definition: %w", err)
+	}
+
+	return nil
+}
+
+// ReorderDefinitions updates display order for multiple definitions
+func (s *UserAttributeService) ReorderDefinitions(ctx context.Context, orders map[int64]int) error {
+	return s.defRepo.UpdateDisplayOrders(ctx, orders)
+}
+
+// GetUserAttributes retrieves all attribute values for a user
+func (s *UserAttributeService) GetUserAttributes(ctx context.Context, userID int64) ([]UserAttributeValue, error) {
+	return s.valueRepo.GetByUserID(ctx, userID)
+}
+
+// GetBatchUserAttributes retrieves attribute values for multiple users
+// Returns a map of userID -> map of attributeID -> value
+func (s *UserAttributeService) GetBatchUserAttributes(ctx context.Context, userIDs []int64) (map[int64]map[int64]string, error) {
+	values, err := s.valueRepo.GetByUserIDs(ctx, userIDs)
+	if err != nil {
+		return nil, err
+	}
+
+	result := make(map[int64]map[int64]string)
+	for _, v := range values {
+		if result[v.UserID] == nil {
+			result[v.UserID] = make(map[int64]string)
+		}
+		result[v.UserID][v.AttributeID] = v.Value
+	}
+
+	return result, nil
+}
+
+// UpdateUserAttributes batch updates attribute values for a user
+func (s *UserAttributeService) UpdateUserAttributes(ctx context.Context, userID int64, inputs []UpdateUserAttributeInput) error {
+	// Validate all values before updating
+	defs, err := s.defRepo.List(ctx, true)
+	if err != nil {
+		return fmt.Errorf("list definitions: %w", err)
+	}
+
+	defMap := make(map[int64]*UserAttributeDefinition, len(defs))
+	for i := range defs {
+		defMap[defs[i].ID] = &defs[i]
+	}
+
+	for _, input := range inputs {
+		def, ok := defMap[input.AttributeID]
+		if !ok {
+			return ErrAttributeDefinitionNotFound
+		}
+
+		if err := s.validateValue(def, input.Value); err != nil {
+			return err
+		}
+	}
+
+	return s.valueRepo.UpsertBatch(ctx, userID, inputs)
+}
+
+// validateValue validates a value against its definition
+func (s *UserAttributeService) validateValue(def *UserAttributeDefinition, value string) error {
+	// Skip validation for empty non-required fields
+	if value == "" && !def.Required {
+		return nil
+	}
+
+	// Required check
+	if def.Required && value == "" {
+		return validationError(fmt.Sprintf("%s is required", def.Name))
+	}
+
+	v := def.Validation
+
+	// String length validation
+	if v.MinLength != nil && len(value) < *v.MinLength {
+		return validationError(fmt.Sprintf("%s must be at least %d characters", def.Name, *v.MinLength))
+	}
+	if v.MaxLength != nil && len(value) > *v.MaxLength {
+		return validationError(fmt.Sprintf("%s must be at most %d characters", def.Name, *v.MaxLength))
+	}
+
+	// Number validation
+	if def.Type == AttributeTypeNumber && value != "" {
+		num, err := strconv.Atoi(value)
+		if err != nil {
+			return validationError(fmt.Sprintf("%s must be a number", def.Name))
+		}
+		if v.Min != nil && num < *v.Min {
+			return validationError(fmt.Sprintf("%s must be at least %d", def.Name, *v.Min))
+		}
+		if v.Max != nil && num > *v.Max {
+			return validationError(fmt.Sprintf("%s must be at most %d", def.Name, *v.Max))
+		}
+	}
+
+	// Pattern validation
+	if v.Pattern != nil && *v.Pattern != "" && value != "" {
+		re, err := regexp.Compile(*v.Pattern)
+		if err == nil && !re.MatchString(value) {
+			msg := def.Name + " format is invalid"
+			if v.Message != nil && *v.Message != "" {
+				msg = *v.Message
+			}
+			return validationError(msg)
+		}
+	}
+
+	// Select validation
+	if def.Type == AttributeTypeSelect && value != "" {
+		found := false
+		for _, opt := range def.Options {
+			if opt.Value == value {
+				found = true
+				break
+			}
+		}
+		if !found {
+			return validationError(fmt.Sprintf("%s: invalid option", def.Name))
+		}
+	}
+
+	// Multi-select validation (stored as JSON array)
+	if def.Type == AttributeTypeMultiSelect && value != "" {
+		var values []string
+		if err := json.Unmarshal([]byte(value), &values); err != nil {
+			// Try comma-separated fallback
+			values = strings.Split(value, ",")
+		}
+		for _, val := range values {
+			val = strings.TrimSpace(val)
+			found := false
+			for _, opt := range def.Options {
+				if opt.Value == val {
+					found = true
+					break
+				}
+			}
+			if !found {
+				return validationError(fmt.Sprintf("%s: invalid option %s", def.Name, val))
+			}
+		}
+	}
+
+	return nil
+}
+
+// validationError creates a validation error with a custom message
+func validationError(msg string) error {
+	return infraerrors.BadRequest("ATTRIBUTE_VALIDATION_FAILED", msg)
+}
+
+func isValidAttributeType(t UserAttributeType) bool {
+	switch t {
+	case AttributeTypeText, AttributeTypeTextarea, AttributeTypeNumber,
+		AttributeTypeEmail, AttributeTypeURL, AttributeTypeDate,
+		AttributeTypeSelect, AttributeTypeMultiSelect:
+		return true
+	}
+	return false
+}

backend/internal/service/user_service.go

@@ -14,6 +14,14 @@ var (
 	ErrInsufficientPerms = infraerrors.Forbidden("INSUFFICIENT_PERMISSIONS", "insufficient permissions")
 )
 
+// UserListFilters contains all filter options for listing users
+type UserListFilters struct {
+	Status     string           // User status filter
+	Role       string           // User role filter
+	Search     string           // Search in email, username
+	Attributes map[int64]string // Custom attribute filters: attributeID -> value
+}
+
 type UserRepository interface {
 	Create(ctx context.Context, user *User) error
 	GetByID(ctx context.Context, id int64) (*User, error)
@@ -23,7 +31,7 @@ type UserRepository interface {
 	Delete(ctx context.Context, id int64) error
 
 	List(ctx context.Context, params pagination.PaginationParams) ([]User, *pagination.PaginationResult, error)
-	ListWithFilters(ctx context.Context, params pagination.PaginationParams, status, role, search string) ([]User, *pagination.PaginationResult, error)
+	ListWithFilters(ctx context.Context, params pagination.PaginationParams, filters UserListFilters) ([]User, *pagination.PaginationResult, error)
 
 	UpdateBalance(ctx context.Context, id int64, amount float64) error
 	DeductBalance(ctx context.Context, id int64, amount float64) error
@@ -36,7 +44,6 @@ type UserRepository interface {
 type UpdateProfileRequest struct {
 	Email       *string `json:"email"`
 	Username    *string `json:"username"`
-	Wechat      *string `json:"wechat"`
 	Concurrency *int    `json:"concurrency"`
 }
 
@@ -100,10 +107,6 @@ func (s *UserService) UpdateProfile(ctx context.Context, userID int64, req Updat
 		user.Username = *req.Username
 	}
 
-	if req.Wechat != nil {
-		user.Wechat = *req.Wechat
-	}
-
 	if req.Concurrency != nil {
 		user.Concurrency = *req.Concurrency
 	}

backend/internal/service/wire.go

@@ -73,6 +73,15 @@ func ProvideDeferredService(accountRepo AccountRepository, timingWheel *TimingWh
 	return svc
 }
 
+// ProvideConcurrencyService creates ConcurrencyService and starts slot cleanup worker.
+func ProvideConcurrencyService(cache ConcurrencyCache, accountRepo AccountRepository, cfg *config.Config) *ConcurrencyService {
+	svc := NewConcurrencyService(cache)
+	if cfg != nil {
+		svc.StartSlotCleanupWorker(accountRepo, cfg.Gateway.Scheduling.SlotCleanupInterval)
+	}
+	return svc
+}
+
 // ProviderSet is the Wire provider set for all services
 var ProviderSet = wire.NewSet(
 	// Core services
@@ -94,6 +103,7 @@ var ProviderSet = wire.NewSet(
 	NewOAuthService,
 	NewOpenAIOAuthService,
 	NewGeminiOAuthService,
+	NewGeminiQuotaService,
 	NewAntigravityOAuthService,
 	NewGeminiTokenProvider,
 	NewGeminiMessagesCompatService,
@@ -107,7 +117,7 @@ var ProviderSet = wire.NewSet(
 	ProvideEmailQueueService,
 	NewTurnstileService,
 	NewSubscriptionService,
-	NewConcurrencyService,
+	ProvideConcurrencyService,
 	NewIdentityService,
 	NewCRSSyncService,
 	ProvideUpdateService,
@@ -115,4 +125,5 @@ var ProviderSet = wire.NewSet(
 	ProvideTimingWheelService,
 	ProvideDeferredService,
 	ProvideAntigravityQuotaRefresher,
+	NewUserAttributeService,
 )

backend/migrations/018_user_attributes.sql

+-- Add user attribute definitions and values tables for custom user attributes.
+
+-- User Attribute Definitions table (with soft delete support)
+CREATE TABLE IF NOT EXISTS user_attribute_definitions (
+    id              BIGSERIAL PRIMARY KEY,
+    key             VARCHAR(100) NOT NULL,
+    name            VARCHAR(255) NOT NULL,
+    description     TEXT DEFAULT '',
+    type            VARCHAR(20) NOT NULL,
+    options         JSONB DEFAULT '[]'::jsonb,
+    required        BOOLEAN NOT NULL DEFAULT FALSE,
+    validation      JSONB DEFAULT '{}'::jsonb,
+    placeholder     VARCHAR(255) DEFAULT '',
+    display_order   INT NOT NULL DEFAULT 0,
+    enabled         BOOLEAN NOT NULL DEFAULT TRUE,
+    created_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    deleted_at      TIMESTAMPTZ
+);
+
+-- Partial unique index for key (only for non-deleted records)
+-- Allows reusing keys after soft delete
+CREATE UNIQUE INDEX IF NOT EXISTS idx_user_attribute_definitions_key_unique
+    ON user_attribute_definitions(key) WHERE deleted_at IS NULL;
+
+CREATE INDEX IF NOT EXISTS idx_user_attribute_definitions_enabled
+    ON user_attribute_definitions(enabled);
+CREATE INDEX IF NOT EXISTS idx_user_attribute_definitions_display_order
+    ON user_attribute_definitions(display_order);
+CREATE INDEX IF NOT EXISTS idx_user_attribute_definitions_deleted_at
+    ON user_attribute_definitions(deleted_at);
+
+-- User Attribute Values table (hard delete only, no deleted_at)
+CREATE TABLE IF NOT EXISTS user_attribute_values (
+    id              BIGSERIAL PRIMARY KEY,
+    user_id         BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    attribute_id    BIGINT NOT NULL REFERENCES user_attribute_definitions(id) ON DELETE CASCADE,
+    value           TEXT DEFAULT '',
+    created_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+
+    UNIQUE(user_id, attribute_id)
+);
+
+CREATE INDEX IF NOT EXISTS idx_user_attribute_values_user_id
+    ON user_attribute_values(user_id);
+CREATE INDEX IF NOT EXISTS idx_user_attribute_values_attribute_id
+    ON user_attribute_values(attribute_id);

backend/migrations/019_migrate_wechat_to_attributes.sql

+-- Migration: Move wechat field from users table to user_attribute_values
+-- This migration:
+-- 1. Creates a "wechat" attribute definition
+-- 2. Migrates existing wechat data to user_attribute_values
+-- 3. Does NOT drop the wechat column (for rollback safety, can be done in a later migration)
+
+-- +goose Up
+-- +goose StatementBegin
+
+-- Step 1: Insert wechat attribute definition if not exists
+INSERT INTO user_attribute_definitions (key, name, description, type, options, required, validation, placeholder, display_order, enabled, created_at, updated_at)
+SELECT 'wechat', '微信', '用户微信号', 'text', '[]'::jsonb, false, '{}'::jsonb, '请输入微信号', 0, true, NOW(), NOW()
+WHERE NOT EXISTS (
+    SELECT 1 FROM user_attribute_definitions WHERE key = 'wechat' AND deleted_at IS NULL
+);
+
+-- Step 2: Migrate existing wechat values to user_attribute_values
+-- Only migrate non-empty values
+INSERT INTO user_attribute_values (user_id, attribute_id, value, created_at, updated_at)
+SELECT
+    u.id,
+    (SELECT id FROM user_attribute_definitions WHERE key = 'wechat' AND deleted_at IS NULL LIMIT 1),
+    u.wechat,
+    NOW(),
+    NOW()
+FROM users u
+WHERE u.wechat IS NOT NULL
+  AND u.wechat != ''
+  AND u.deleted_at IS NULL
+  AND NOT EXISTS (
+      SELECT 1 FROM user_attribute_values uav
+      WHERE uav.user_id = u.id
+        AND uav.attribute_id = (SELECT id FROM user_attribute_definitions WHERE key = 'wechat' AND deleted_at IS NULL LIMIT 1)
+  );
+
+-- Step 3: Update display_order to ensure wechat appears first
+UPDATE user_attribute_definitions
+SET display_order = -1
+WHERE key = 'wechat' AND deleted_at IS NULL;
+
+-- Reorder all attributes starting from 0
+WITH ordered AS (
+    SELECT id, ROW_NUMBER() OVER (ORDER BY display_order, id) - 1 as new_order
+    FROM user_attribute_definitions
+    WHERE deleted_at IS NULL
+)
+UPDATE user_attribute_definitions
+SET display_order = ordered.new_order
+FROM ordered
+WHERE user_attribute_definitions.id = ordered.id;
+
+-- Step 4: Drop the redundant wechat column from users table
+ALTER TABLE users DROP COLUMN IF EXISTS wechat;
+
+-- +goose StatementEnd
+
+-- +goose Down
+-- +goose StatementBegin
+
+-- Restore wechat column
+ALTER TABLE users ADD COLUMN IF NOT EXISTS wechat VARCHAR(100) DEFAULT '';
+
+-- Copy attribute values back to users.wechat column
+UPDATE users u
+SET wechat = uav.value
+FROM user_attribute_values uav
+JOIN user_attribute_definitions uad ON uav.attribute_id = uad.id
+WHERE uav.user_id = u.id
+  AND uad.key = 'wechat'
+  AND uad.deleted_at IS NULL;
+
+-- Delete migrated attribute values
+DELETE FROM user_attribute_values
+WHERE attribute_id IN (
+    SELECT id FROM user_attribute_definitions WHERE key = 'wechat' AND deleted_at IS NULL
+);
+
+-- Soft-delete the wechat attribute definition
+UPDATE user_attribute_definitions
+SET deleted_at = NOW()
+WHERE key = 'wechat' AND deleted_at IS NULL;
+
+-- +goose StatementEnd