refactor: Move more helper files into libxrpl/ledger/helpers (#6731)

Co-authored-by: xrplf-ai-reviewer[bot] <266832837+xrplf-ai-reviewer[bot]@users.noreply.github.com>

include/xrpl/ledger/helpers/EscrowHelpers.h

@@ -0,0 +1,228 @@
+#pragma once
+
+#include <xrpl/basics/Log.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/MPTokenHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/MPTAmount.h>
+#include <xrpl/protocol/Rate.h>
+
+namespace xrpl {
+
+template <ValidIssueType T>
+TER
+escrowUnlockApplyHelper(
+    ApplyView& view,
+    Rate lockedRate,
+    std::shared_ptr<SLE> const& sleDest,
+    STAmount const& xrpBalance,
+    STAmount const& amount,
+    AccountID const& issuer,
+    AccountID const& sender,
+    AccountID const& receiver,
+    bool createAsset,
+    beast::Journal journal);
+
+template <>
+inline TER
+escrowUnlockApplyHelper<Issue>(
+    ApplyView& view,
+    Rate lockedRate,
+    std::shared_ptr<SLE> const& sleDest,
+    STAmount const& xrpBalance,
+    STAmount const& amount,
+    AccountID const& issuer,
+    AccountID const& sender,
+    AccountID const& receiver,
+    bool createAsset,
+    beast::Journal journal)
+{
+    Keylet const trustLineKey = keylet::line(receiver, amount.issue());
+    bool const recvLow = issuer > receiver;
+    bool const senderIssuer = issuer == sender;
+    bool const receiverIssuer = issuer == receiver;
+
+    if (senderIssuer)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    if (receiverIssuer)
+        return tesSUCCESS;
+
+    if (!view.exists(trustLineKey) && createAsset)
+    {
+        // Can the account cover the trust line's reserve?
+        if (std::uint32_t const ownerCount = {sleDest->at(sfOwnerCount)};
+            xrpBalance < view.fees().accountReserve(ownerCount + 1))
+        {
+            JLOG(journal.trace()) << "Trust line does not exist. "
+                                     "Insufficient reserve to create line.";
+
+            return tecNO_LINE_INSUF_RESERVE;
+        }
+
+        Currency const currency = amount.getCurrency();
+        STAmount initialBalance(amount.issue());
+        initialBalance.setIssuer(noAccount());
+
+        if (TER const ter = trustCreate(
+                view,                                           // payment sandbox
+                recvLow,                                        // is dest low?
+                issuer,                                         // source
+                receiver,                                       // destination
+                trustLineKey.key,                               // ledger index
+                sleDest,                                        // Account to add to
+                false,                                          // authorize account
+                (sleDest->getFlags() & lsfDefaultRipple) == 0,  //
+                false,                                          // freeze trust line
+                false,                                          // deep freeze trust line
+                initialBalance,                                 // zero initial balance
+                Issue(currency, receiver),                      // limit of zero
+                0,                                              // quality in
+                0,                                              // quality out
+                journal);                                       // journal
+            !isTesSuccess(ter))
+        {
+            return ter;  // LCOV_EXCL_LINE
+        }
+
+        view.update(sleDest);
+    }
+
+    if (!view.exists(trustLineKey) && !receiverIssuer)
+        return tecNO_LINE;
+
+    auto const xferRate = transferRate(view, amount);
+    // update if issuer rate is less than locked rate
+    if (xferRate < lockedRate)
+        lockedRate = xferRate;
+
+    // Transfer Rate only applies when:
+    // 1. Issuer is not involved in the transfer (senderIssuer or
+    // receiverIssuer)
+    // 2. The locked rate is different from the parity rate
+
+    // NOTE: Transfer fee in escrow works a bit differently from a normal
+    // payment. In escrow, the fee is deducted from the locked/sending amount,
+    // whereas in a normal payment, the transfer fee is taken on top of the
+    // sending amount.
+    auto finalAmt = amount;
+    if ((!senderIssuer && !receiverIssuer) && lockedRate != parityRate)
+    {
+        // compute transfer fee, if any
+        auto const xferFee = amount.value() - divideRound(amount, lockedRate, amount.issue(), true);
+        // compute balance to transfer
+        finalAmt = amount.value() - xferFee;
+    }
+
+    // validate the line limit if the account submitting txn is not the receiver
+    // of the funds
+    if (!createAsset)
+    {
+        auto const sleRippleState = view.peek(trustLineKey);
+        if (!sleRippleState)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        // if the issuer is the high, then we use the low limit
+        // otherwise we use the high limit
+        STAmount const lineLimit =
+            sleRippleState->getFieldAmount(recvLow ? sfLowLimit : sfHighLimit);
+
+        STAmount lineBalance = sleRippleState->getFieldAmount(sfBalance);
+
+        // flip the sign of the line balance if the issuer is not high
+        if (!recvLow)
+            lineBalance.negate();
+
+        // add the final amount to the line balance
+        lineBalance += finalAmt;
+
+        // if the transfer would exceed the line limit return tecLIMIT_EXCEEDED
+        if (lineLimit < lineBalance)
+            return tecLIMIT_EXCEEDED;
+    }
+
+    // if destination is not the issuer then transfer funds
+    if (!receiverIssuer)
+    {
+        auto const ter = rippleCredit(view, issuer, receiver, finalAmt, true, journal);
+        if (!isTesSuccess(ter))
+            return ter;  // LCOV_EXCL_LINE
+    }
+    return tesSUCCESS;
+}
+
+template <>
+inline TER
+escrowUnlockApplyHelper<MPTIssue>(
+    ApplyView& view,
+    Rate lockedRate,
+    std::shared_ptr<SLE> const& sleDest,
+    STAmount const& xrpBalance,
+    STAmount const& amount,
+    AccountID const& issuer,
+    AccountID const& sender,
+    AccountID const& receiver,
+    bool createAsset,
+    beast::Journal journal)
+{
+    bool const senderIssuer = issuer == sender;
+    bool const receiverIssuer = issuer == receiver;
+
+    auto const mptID = amount.get<MPTIssue>().getMptID();
+    auto const issuanceKey = keylet::mptIssuance(mptID);
+    if (!view.exists(keylet::mptoken(issuanceKey.key, receiver)) && createAsset && !receiverIssuer)
+    {
+        if (std::uint32_t const ownerCount = {sleDest->at(sfOwnerCount)};
+            xrpBalance < view.fees().accountReserve(ownerCount + 1))
+        {
+            return tecINSUFFICIENT_RESERVE;
+        }
+
+        if (auto const ter = createMPToken(view, mptID, receiver, 0); !isTesSuccess(ter))
+        {
+            return ter;  // LCOV_EXCL_LINE
+        }
+
+        // update owner count.
+        adjustOwnerCount(view, sleDest, 1, journal);
+    }
+
+    if (!view.exists(keylet::mptoken(issuanceKey.key, receiver)) && !receiverIssuer)
+        return tecNO_PERMISSION;
+
+    auto const xferRate = transferRate(view, amount);
+    // update if issuer rate is less than locked rate
+    if (xferRate < lockedRate)
+        lockedRate = xferRate;
+
+    // Transfer Rate only applies when:
+    // 1. Issuer is not involved in the transfer (senderIssuer or
+    // receiverIssuer)
+    // 2. The locked rate is different from the parity rate
+
+    // NOTE: Transfer fee in escrow works a bit differently from a normal
+    // payment. In escrow, the fee is deducted from the locked/sending amount,
+    // whereas in a normal payment, the transfer fee is taken on top of the
+    // sending amount.
+    auto finalAmt = amount;
+    if ((!senderIssuer && !receiverIssuer) && lockedRate != parityRate)
+    {
+        // compute transfer fee, if any
+        auto const xferFee = amount.value() - divideRound(amount, lockedRate, amount.asset(), true);
+        // compute balance to transfer
+        finalAmt = amount.value() - xferFee;
+    }
+    return rippleUnlockEscrowMPT(
+        view,
+        sender,
+        receiver,
+        finalAmt,
+        view.rules().enabled(fixTokenEscrowV1) ? amount : finalAmt,
+        journal);
+}
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/MPTokenHelpers.h

@@ -157,4 +157,11 @@ rippleUnlockEscrowMPT(
     STAmount const& grossAmount,
     beast::Journal j);
 
+TER
+createMPToken(
+    ApplyView& view,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    std::uint32_t const flags);
+
 }  // namespace xrpl

include/xrpl/ledger/helpers/NFTokenHelpers.h

@@ -1,12 +1,12 @@
 #pragma once
 
+#include <xrpl/basics/Log.h>
 #include <xrpl/basics/base_uint.h>
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/protocol/nft.h>
-#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/ledger/helpers/PaymentChannelHelpers.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/protocol/UintTypes.h>
+
+namespace xrpl {
+
+TER
+closeChannel(
+    std::shared_ptr<SLE> const& slep,
+    ApplyView& view,
+    uint256 const& key,
+    beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/tx/paths/AMMLiquidity.h

@@ -3,10 +3,10 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ReadView.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AMMHelpers.h>
+#include <xrpl/ledger/helpers/AMMUtils.h>
 #include <xrpl/protocol/Quality.h>
 #include <xrpl/tx/transactors/dex/AMMContext.h>
-#include <xrpl/tx/transactors/dex/AMMHelpers.h>
-#include <xrpl/tx/transactors/dex/AMMUtils.h>
 
 namespace xrpl {
 

include/xrpl/tx/paths/detail/StrandFlow.h

@@ -2,6 +2,7 @@
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AMMHelpers.h>
 #include <xrpl/ledger/helpers/OfferHelpers.h>
 #include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
@@ -13,7 +14,6 @@
 #include <xrpl/tx/paths/detail/FlowDebugInfo.h>
 #include <xrpl/tx/paths/detail/Steps.h>
 #include <xrpl/tx/transactors/dex/AMMContext.h>
-#include <xrpl/tx/transactors/dex/AMMHelpers.h>
 
 #include <boost/container/flat_set.hpp>
 

include/xrpl/tx/transactors/nft/NFTokenMint.h

@@ -1,8 +1,8 @@
 #pragma once
 
+#include <xrpl/ledger/helpers/NFTokenHelpers.h>
 #include <xrpl/protocol/nft.h>
 #include <xrpl/tx/Transactor.h>
-#include <xrpl/tx/transactors/nft/NFTokenUtils.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/token/MPTokenAuthorize.h

@@ -31,13 +31,6 @@ public:
     static TER
     preclaim(PreclaimContext const& ctx);
 
-    static TER
-    createMPToken(
-        ApplyView& view,
-        MPTID const& mptIssuanceID,
-        AccountID const& account,
-        std::uint32_t const flags);
-
     TER
     doApply() override;
 };