chore: initial public snapshot for github upload

llm-gateway-competitors/sub2api-tar/backend/internal/service/model_rate_limit.go

@@ -0,0 +1,101 @@
+package service
+
+import (
+	"context"
+	"strings"
+	"time"
+)
+
+const modelRateLimitsKey = "model_rate_limits"
+
+// isRateLimitActiveForKey 检查指定 key 的限流是否生效
+func (a *Account) isRateLimitActiveForKey(key string) bool {
+	resetAt := a.modelRateLimitResetAt(key)
+	return resetAt != nil && time.Now().Before(*resetAt)
+}
+
+// getRateLimitRemainingForKey 获取指定 key 的限流剩余时间，0 表示未限流或已过期
+func (a *Account) getRateLimitRemainingForKey(key string) time.Duration {
+	resetAt := a.modelRateLimitResetAt(key)
+	if resetAt == nil {
+		return 0
+	}
+	remaining := time.Until(*resetAt)
+	if remaining > 0 {
+		return remaining
+	}
+	return 0
+}
+
+func (a *Account) isModelRateLimitedWithContext(ctx context.Context, requestedModel string) bool {
+	if a == nil {
+		return false
+	}
+
+	modelKey := a.GetMappedModel(requestedModel)
+	if a.Platform == PlatformAntigravity {
+		modelKey = resolveFinalAntigravityModelKey(ctx, a, requestedModel)
+	}
+	modelKey = strings.TrimSpace(modelKey)
+	if modelKey == "" {
+		return false
+	}
+	return a.isRateLimitActiveForKey(modelKey)
+}
+
+// GetModelRateLimitRemainingTime 获取模型限流剩余时间
+// 返回 0 表示未限流或已过期
+func (a *Account) GetModelRateLimitRemainingTime(requestedModel string) time.Duration {
+	return a.GetModelRateLimitRemainingTimeWithContext(context.Background(), requestedModel)
+}
+
+func (a *Account) GetModelRateLimitRemainingTimeWithContext(ctx context.Context, requestedModel string) time.Duration {
+	if a == nil {
+		return 0
+	}
+
+	modelKey := a.GetMappedModel(requestedModel)
+	if a.Platform == PlatformAntigravity {
+		modelKey = resolveFinalAntigravityModelKey(ctx, a, requestedModel)
+	}
+	modelKey = strings.TrimSpace(modelKey)
+	if modelKey == "" {
+		return 0
+	}
+	return a.getRateLimitRemainingForKey(modelKey)
+}
+
+func resolveFinalAntigravityModelKey(ctx context.Context, account *Account, requestedModel string) string {
+	modelKey := mapAntigravityModel(account, requestedModel)
+	if modelKey == "" {
+		return ""
+	}
+	// thinking 会影响 Antigravity 最终模型名（例如 claude-sonnet-4-5 -> claude-sonnet-4-5-thinking）
+	if enabled, ok := ThinkingEnabledFromContext(ctx); ok {
+		modelKey = applyThinkingModelSuffix(modelKey, enabled)
+	}
+	return modelKey
+}
+
+func (a *Account) modelRateLimitResetAt(scope string) *time.Time {
+	if a == nil || a.Extra == nil || scope == "" {
+		return nil
+	}
+	rawLimits, ok := a.Extra[modelRateLimitsKey].(map[string]any)
+	if !ok {
+		return nil
+	}
+	rawLimit, ok := rawLimits[scope].(map[string]any)
+	if !ok {
+		return nil
+	}
+	resetAtRaw, ok := rawLimit["rate_limit_reset_at"].(string)
+	if !ok || strings.TrimSpace(resetAtRaw) == "" {
+		return nil
+	}
+	resetAt, err := time.Parse(time.RFC3339, resetAtRaw)
+	if err != nil {
+		return nil
+	}
+	return &resetAt
+}