实现套餐生效条件覆盖与购买快照

internal/service/package/usage_terms.go

@@ -0,0 +1,47 @@
+package packagepkg
+
+import (
+	"sync/atomic"
+
+	packagedomain "github.com/break/junhong_cmp_fiber/internal/domain/package"
+	"github.com/break/junhong_cmp_fiber/internal/model"
+	"github.com/break/junhong_cmp_fiber/pkg/errors"
+	"go.uber.org/zap"
+)
+
+var historicalTermsFallbackCount atomic.Uint64
+
+// ResolveUsageTerms 优先读取使用记录快照，仅对完整空快照的历史记录显式回退。
+func ResolveUsageTerms(usage *model.PackageUsage, pkg *model.Package, logger *zap.Logger) (packagedomain.TermsSnapshot, error) {
+	terms := packagedomain.TermsSnapshotFromUsage(usage)
+	if terms.IsValid() {
+		return terms, nil
+	}
+	if !isEmptyHistoricalTerms(usage) {
+		if logger != nil {
+			logger.Error("套餐使用记录计时快照异常", zap.Uint("package_usage_id", usage.ID), zap.Uint("package_id", usage.PackageID))
+		}
+		return packagedomain.TermsSnapshot{}, errors.New(errors.CodeInternalError, "套餐使用记录计时快照异常")
+	}
+	fallback, err := packagedomain.ResolveTermsSnapshot(pkg, nil)
+	if err != nil {
+		return packagedomain.TermsSnapshot{}, err
+	}
+	historicalTermsFallbackCount.Add(1)
+	if logger != nil {
+		logger.Warn("历史套餐使用记录缺少计时快照，回退套餐当前配置",
+			zap.Uint("package_usage_id", usage.ID), zap.Uint("package_id", usage.PackageID),
+			zap.Uint64("historical_terms_fallback_count", historicalTermsFallbackCount.Load()))
+	}
+	return fallback, nil
+}
+
+// HistoricalTermsFallbackCount 返回历史计时条款回退累计次数。
+func HistoricalTermsFallbackCount() uint64 {
+	return historicalTermsFallbackCount.Load()
+}
+
+func isEmptyHistoricalTerms(usage *model.PackageUsage) bool {
+	return usage.ExpiryBaseSnapshot == "" && usage.CalendarTypeSnapshot == "" &&
+		usage.DurationMonthsSnapshot == 0 && usage.DurationDaysSnapshot == 0
+}