From ee8643f533dad7129666372f61c1cc9ef43909e6 Mon Sep 17 00:00:00 2001
From: Ed Hennis <ed@ripple.com>
Date: Tue, 6 May 2025 18:40:34 -0400
Subject: [PATCH] Restructure the LendingHelpers files

---
 src/xrpld/app/misc/LendingHelpers.h          | 72 ++++++--------------
 src/xrpld/app/misc/detail/LendingHelpers.cpp | 68 ++++++++++++++++++
 2 files changed, 88 insertions(+), 52 deletions(-)

diff --git a/src/xrpld/app/misc/LendingHelpers.h b/src/xrpld/app/misc/LendingHelpers.h
index b0891f0a87..0b300aa753 100644
--- a/src/xrpld/app/misc/LendingHelpers.h
+++ b/src/xrpld/app/misc/LendingHelpers.h
@@ -20,80 +20,48 @@
 #ifndef RIPPLE_APP_MISC_LENDINGHELPERS_H_INCLUDED
 #define RIPPLE_APP_MISC_LENDINGHELPERS_H_INCLUDED
 
-#include <xrpld/app/tx/detail/Transactor.h>
-#include <xrpld/app/tx/detail/VaultCreate.h>
-
 #include <xrpl/basics/Number.h>
+#include <xrpl/protocol/Asset.h>
 #include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Protocol.h>
 
 namespace ripple {
 
-class PreflightContext;
+struct PreflightContext;
 
 // Lending protocol has dependencies, so capture them here.
-inline bool
-LendingProtocolEnabled(PreflightContext const& ctx)
-{
-    return ctx.rules.enabled(featureLendingProtocol) &&
-        VaultCreate::isEnabled(ctx);
-}
+bool
+LendingProtocolEnabled(PreflightContext const& ctx);
 
-inline Number
-LoanPeriodicRate(TenthBips32 interestRate, std::uint32_t paymentInterval)
-{
-    // Need floating point math for this one, since we're dividing by some large
-    // numbers
-    return tenthBipsOfValue(Number(paymentInterval), interestRate) /
-        (365 * 24 * 60 * 60);
-}
+namespace detail {
+// These functions should rarely be used directly. More often, the ultimate
+// result needs to be roundToAsset'd.
 
-inline Number
+Number
+LoanPeriodicRate(TenthBips32 interestRate, std::uint32_t paymentInterval);
+
+Number
 LoanPeriodicPayment(
     Number principalOutstanding,
     TenthBips32 interestRate,
     std::uint32_t paymentInterval,
-    std::uint32_t paymentsRemaining)
-{
-    if (principalOutstanding == 0 || paymentsRemaining == 0)
-        return 0;
-    Number const periodicRate = LoanPeriodicRate(interestRate, paymentInterval);
+    std::uint32_t paymentsRemaining);
 
-    // TODO: Need a better name
-    Number const timeFactor = power(1 + periodicRate, paymentsRemaining);
-
-    return principalOutstanding * (periodicRate * timeFactor) /
-        (timeFactor - 1);
-}
-
-inline Number
+Number
 LoanTotalValueOutstanding(
     Number principalOutstanding,
     TenthBips32 interestRate,
     std::uint32_t paymentInterval,
-    std::uint32_t paymentsRemaining)
-{
-    return LoanPeriodicPayment(
-               principalOutstanding,
-               interestRate,
-               paymentInterval,
-               paymentsRemaining) *
-        paymentsRemaining;
-}
+    std::uint32_t paymentsRemaining);
 
-inline Number
+Number
 LoanTotalInterestOutstanding(
     Number principalOutstanding,
     TenthBips32 interestRate,
     std::uint32_t paymentInterval,
-    std::uint32_t paymentsRemaining)
-{
-    return LoanTotalValueOutstanding(
-               principalOutstanding,
-               interestRate,
-               paymentInterval,
-               paymentsRemaining) -
-        principalOutstanding;
-}
+    std::uint32_t paymentsRemaining);
+
+}  // namespace detail
 
 template <AssetType A>
 Number
@@ -108,7 +76,7 @@ LoanInterestOutstandingToVault(
     return roundToAsset(
         asset,
         tenthBipsOfValue(
-            LoanTotalInterestOutstanding(
+            detail::LoanTotalInterestOutstanding(
                 principalOutstanding,
                 interestRate,
                 paymentInterval,
diff --git a/src/xrpld/app/misc/detail/LendingHelpers.cpp b/src/xrpld/app/misc/detail/LendingHelpers.cpp
index 78a9011f16..7b6e186922 100644
--- a/src/xrpld/app/misc/detail/LendingHelpers.cpp
+++ b/src/xrpld/app/misc/detail/LendingHelpers.cpp
@@ -26,4 +26,72 @@
 
 namespace ripple {
 
+bool
+LendingProtocolEnabled(PreflightContext const& ctx)
+{
+    return ctx.rules.enabled(featureLendingProtocol) &&
+        VaultCreate::isEnabled(ctx);
+}
+
+namespace detail {
+
+Number
+LoanPeriodicRate(TenthBips32 interestRate, std::uint32_t paymentInterval)
+{
+    // Need floating point math for this one, since we're dividing by some
+    // large numbers
+    return tenthBipsOfValue(Number(paymentInterval), interestRate) /
+        (365 * 24 * 60 * 60);
+}
+
+Number
+LoanPeriodicPayment(
+    Number principalOutstanding,
+    TenthBips32 interestRate,
+    std::uint32_t paymentInterval,
+    std::uint32_t paymentsRemaining)
+{
+    if (principalOutstanding == 0 || paymentsRemaining == 0)
+        return 0;
+    Number const periodicRate = LoanPeriodicRate(interestRate, paymentInterval);
+
+    // TODO: Need a better name
+    Number const timeFactor = power(1 + periodicRate, paymentsRemaining);
+
+    return principalOutstanding * (periodicRate * timeFactor) /
+        (timeFactor - 1);
+}
+
+Number
+LoanTotalValueOutstanding(
+    Number principalOutstanding,
+    TenthBips32 interestRate,
+    std::uint32_t paymentInterval,
+    std::uint32_t paymentsRemaining)
+{
+    return LoanPeriodicPayment(
+               principalOutstanding,
+               interestRate,
+               paymentInterval,
+               paymentsRemaining) *
+        paymentsRemaining;
+}
+
+Number
+LoanTotalInterestOutstanding(
+    Number principalOutstanding,
+    TenthBips32 interestRate,
+    std::uint32_t paymentInterval,
+    std::uint32_t paymentsRemaining)
+{
+    return LoanTotalValueOutstanding(
+               principalOutstanding,
+               interestRate,
+               paymentInterval,
+               paymentsRemaining) -
+        principalOutstanding;
+}
+
+}  // namespace detail
+
 }  // namespace ripple