feat: implement tiered billing expression evaluation and related functionality

- Added support for tiered billing expressions in the billing system.
- Introduced new types and functions for handling billing expressions, including caching and execution.
- Updated existing billing logic to accommodate tiered billing scenarios.
- Enhanced request handling to support incoming billing expression requests.
- Added tests for tiered billing functionality to ensure correctness.

service/log_info_generate.go

@@ -6,6 +6,7 @@ import (
 	"github.com/QuantumNous/new-api/common"
 	"github.com/QuantumNous/new-api/constant"
 	"github.com/QuantumNous/new-api/dto"
+	"github.com/QuantumNous/new-api/pkg/billingexpr"
 	relaycommon "github.com/QuantumNous/new-api/relay/common"
 	"github.com/QuantumNous/new-api/types"
 
@@ -214,3 +215,42 @@ func GenerateMjOtherInfo(relayInfo *relaycommon.RelayInfo, priceData types.Price
 	appendRequestPath(nil, relayInfo, other)
 	return other
 }
+
+func GenerateTieredOtherInfo(ctx *gin.Context, relayInfo *relaycommon.RelayInfo, result *billingexpr.TieredResult) map[string]interface{} {
+	other := make(map[string]interface{})
+	other["billing_mode"] = "tiered_expr"
+
+	snap := relayInfo.TieredBillingSnapshot
+	if snap != nil {
+		other["group_ratio"] = snap.GroupRatio
+		other["expr_hash"] = snap.ExprHash
+		other["estimated_prompt_tokens"] = snap.EstimatedPromptTokens
+		other["estimated_completion_tokens"] = snap.EstimatedCompletionTokens
+		other["estimated_quota_before_group"] = snap.EstimatedQuotaBeforeGroup
+		other["estimated_quota_after_group"] = snap.EstimatedQuotaAfterGroup
+		other["estimated_tier"] = snap.EstimatedTier
+	}
+
+	if result != nil {
+		other["actual_quota_before_group"] = result.ActualQuotaBeforeGroup
+		other["actual_quota_after_group"] = result.ActualQuotaAfterGroup
+		other["matched_tier"] = result.MatchedTier
+		other["crossed_tier"] = result.CrossedTier
+	}
+
+	other["frt"] = float64(relayInfo.FirstResponseTime.UnixMilli() - relayInfo.StartTime.UnixMilli())
+	if relayInfo.IsModelMapped {
+		other["is_model_mapped"] = true
+		other["upstream_model_name"] = relayInfo.UpstreamModelName
+	}
+
+	adminInfo := make(map[string]interface{})
+	adminInfo["use_channel"] = ctx.GetStringSlice("use_channel")
+	AppendChannelAffinityAdminInfo(ctx, adminInfo)
+	other["admin_info"] = adminInfo
+
+	appendRequestPath(ctx, relayInfo, other)
+	appendRequestConversionChain(relayInfo, other)
+	appendBillingInfo(relayInfo, other)
+	return other
+}