View.h

#ifndef XRPL_LEDGER_VIEW_H_INCLUDED
#define XRPL_LEDGER_VIEW_H_INCLUDED
 
#include <xrpl/beast/utility/Journal.h>
#include <xrpl/ledger/ApplyView.h>
#include <xrpl/ledger/OpenView.h>
#include <xrpl/ledger/ReadView.h>
#include <xrpl/protocol/Indexes.h>
#include <xrpl/protocol/MPTIssue.h>
#include <xrpl/protocol/Protocol.h>
#include <xrpl/protocol/Rate.h>
#include <xrpl/protocol/STLedgerEntry.h>
#include <xrpl/protocol/STObject.h>
#include <xrpl/protocol/Serializer.h>
#include <xrpl/protocol/TER.h>
 
#include <functional>
#include <initializer_list>
#include <map>
#include <utility>
 
namespace ripple {
 
enum class WaiveTransferFee : bool { No = false, Yes };
enum class SkipEntry : bool { No = false, Yes };
 
//------------------------------------------------------------------------------
//
// Observers
//
//------------------------------------------------------------------------------
 
[[nodiscard]] bool
hasExpired(ReadView const& view, std::optional<std::uint32_t> const& exp);
 
enum FreezeHandling { fhIGNORE_FREEZE, fhZERO_IF_FROZEN };
 
enum AuthHandling { ahIGNORE_AUTH, ahZERO_IF_UNAUTHORIZED };
 
[[nodiscard]] bool
isGlobalFrozen(ReadView const& view, AccountID const& issuer);
 
[[nodiscard]] bool
isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue);
 
[[nodiscard]] bool
isGlobalFrozen(ReadView const& view, Asset const& asset);
 
// Note, depth parameter is used to limit the recursion depth
[[nodiscard]] bool
isVaultPseudoAccountFrozen(
    ReadView const& view,
    AccountID const& account,
    MPTIssue const& mptShare,
    int depth);
 
[[nodiscard]] bool
isIndividualFrozen(
    ReadView const& view,
    AccountID const& account,
    Currency const& currency,
    AccountID const& issuer);
 
[[nodiscard]] inline bool
isIndividualFrozen(
    ReadView const& view,
    AccountID const& account,
    Issue const& issue)
{
    return isIndividualFrozen(view, account, issue.currency, issue.account);
}
 
[[nodiscard]] bool
isIndividualFrozen(
    ReadView const& view,
    AccountID const& account,
    MPTIssue const& mptIssue);
 
[[nodiscard]] inline bool
isIndividualFrozen(
    ReadView const& view,
    AccountID const& account,
    Asset const& asset)
{
    return std::visit(
        [&](auto const& issue) {
            return isIndividualFrozen(view, account, issue);
        },
        asset.value());
}
 
[[nodiscard]] bool
isFrozen(
    ReadView const& view,
    AccountID const& account,
    Currency const& currency,
    AccountID const& issuer);
 
[[nodiscard]] inline bool
isFrozen(
    ReadView const& view,
    AccountID const& account,
    Issue const& issue,
    int = 0 /*ignored*/)
{
    return isFrozen(view, account, issue.currency, issue.account);
}
 
[[nodiscard]] bool
isFrozen(
    ReadView const& view,
    AccountID const& account,
    MPTIssue const& mptIssue,
    int depth = 0);
 
[[nodiscard]] inline bool
isFrozen(
    ReadView const& view,
    AccountID const& account,
    Asset const& asset,
    int depth = 0)
{
    return std::visit(
        [&](auto const& issue) {
            return isFrozen(view, account, issue, depth);
        },
        asset.value());
}
 
[[nodiscard]] inline TER
checkFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
{
    return isFrozen(view, account, issue) ? (TER)tecFROZEN : (TER)tesSUCCESS;
}
 
[[nodiscard]] inline TER
checkFrozen(
    ReadView const& view,
    AccountID const& account,
    MPTIssue const& mptIssue)
{
    return isFrozen(view, account, mptIssue) ? (TER)tecLOCKED : (TER)tesSUCCESS;
}
 
[[nodiscard]] inline TER
checkFrozen(ReadView const& view, AccountID const& account, Asset const& asset)
{
    return std::visit(
        [&](auto const& issue) { return checkFrozen(view, account, issue); },
        asset.value());
}
 
[[nodiscard]] bool
isAnyFrozen(
    ReadView const& view,
    std::initializer_list<AccountID> const& accounts,
    MPTIssue const& mptIssue,
    int depth = 0);
 
[[nodiscard]] inline bool
isAnyFrozen(
    ReadView const& view,
    std::initializer_list<AccountID> const& accounts,
    Issue const& issue)
{
    for (auto const& account : accounts)
    {
        if (isFrozen(view, account, issue.currency, issue.account))
            return true;
    }
    return false;
}
 
[[nodiscard]] inline bool
isAnyFrozen(
    ReadView const& view,
    std::initializer_list<AccountID> const& accounts,
    Asset const& asset,
    int depth = 0)
{
    return std::visit(
        [&]<ValidIssueType TIss>(TIss const& issue) {
            if constexpr (std::is_same_v<TIss, Issue>)
                return isAnyFrozen(view, accounts, issue);
            else
                return isAnyFrozen(view, accounts, issue, depth);
        },
        asset.value());
}
 
[[nodiscard]] bool
isDeepFrozen(
    ReadView const& view,
    AccountID const& account,
    Currency const& currency,
    AccountID const& issuer);
 
[[nodiscard]] bool
isLPTokenFrozen(
    ReadView const& view,
    AccountID const& account,
    Issue const& asset,
    Issue const& asset2);
 
// Returns the amount an account can spend without going into debt.
//
// <-- saAmount: amount of currency held by account. May be negative.
[[nodiscard]] STAmount
accountHolds(
    ReadView const& view,
    AccountID const& account,
    Currency const& currency,
    AccountID const& issuer,
    FreezeHandling zeroIfFrozen,
    beast::Journal j);
 
[[nodiscard]] STAmount
accountHolds(
    ReadView const& view,
    AccountID const& account,
    Issue const& issue,
    FreezeHandling zeroIfFrozen,
    beast::Journal j);
 
[[nodiscard]] STAmount
accountHolds(
    ReadView const& view,
    AccountID const& account,
    MPTIssue const& mptIssue,
    FreezeHandling zeroIfFrozen,
    AuthHandling zeroIfUnauthorized,
    beast::Journal j);
 
[[nodiscard]] STAmount
accountHolds(
    ReadView const& view,
    AccountID const& account,
    Asset const& asset,
    FreezeHandling zeroIfFrozen,
    AuthHandling zeroIfUnauthorized,
    beast::Journal j);
 
// Returns the amount an account can spend of the currency type saDefault, or
// returns saDefault if this account is the issuer of the currency in
// question. Should be used in favor of accountHolds when questioning how much
// an account can spend while also allowing currency issuers to spend
// unlimited amounts of their own currency (since they can always issue more).
[[nodiscard]] STAmount
accountFunds(
    ReadView const& view,
    AccountID const& id,
    STAmount const& saDefault,
    FreezeHandling freezeHandling,
    beast::Journal j);
 
// Return the account's liquid (not reserved) XRP.  Generally prefer
// calling accountHolds() over this interface.  However, this interface
// allows the caller to temporarily adjust the owner count should that be
// necessary.
//
// @param ownerCountAdj positive to add to count, negative to reduce count.
[[nodiscard]] XRPAmount
xrpLiquid(
    ReadView const& view,
    AccountID const& id,
    std::int32_t ownerCountAdj,
    beast::Journal j);
 
void
forEachItem(
    ReadView const& view,
    Keylet const& root,
    std::function<void(std::shared_ptr<SLE const> const&)> const& f);
 
bool
forEachItemAfter(
    ReadView const& view,
    Keylet const& root,
    uint256 const& after,
    std::uint64_t const hint,
    unsigned int limit,
    std::function<bool(std::shared_ptr<SLE const> const&)> const& f);
 
inline void
forEachItem(
    ReadView const& view,
    AccountID const& id,
    std::function<void(std::shared_ptr<SLE const> const&)> const& f)
{
    return forEachItem(view, keylet::ownerDir(id), f);
}
 
inline bool
forEachItemAfter(
    ReadView const& view,
    AccountID const& id,
    uint256 const& after,
    std::uint64_t const hint,
    unsigned int limit,
    std::function<bool(std::shared_ptr<SLE const> const&)> const& f)
{
    return forEachItemAfter(view, keylet::ownerDir(id), after, hint, limit, f);
}
 
[[nodiscard]] Rate
transferRate(ReadView const& view, AccountID const& issuer);
 
[[nodiscard]] Rate
transferRate(ReadView const& view, MPTID const& issuanceID);
 
[[nodiscard]] Rate
transferRate(ReadView const& view, STAmount const& amount);
 
[[nodiscard]] bool
dirIsEmpty(ReadView const& view, Keylet const& k);
 
// Return the list of enabled amendments
[[nodiscard]] std::set<uint256>
getEnabledAmendments(ReadView const& view);
 
// Return a map of amendments that have achieved majority
using majorityAmendments_t = std::map<uint256, NetClock::time_point>;
[[nodiscard]] majorityAmendments_t
getMajorityAmendments(ReadView const& view);
 
[[nodiscard]] std::optional<uint256>
hashOfSeq(ReadView const& ledger, LedgerIndex seq, beast::Journal journal);
 
inline LedgerIndex
getCandidateLedger(LedgerIndex requested)
{
    return (requested + 255) & (~255);
}
 
[[nodiscard]] bool
areCompatible(
    ReadView const& validLedger,
    ReadView const& testLedger,
    beast::Journal::Stream& s,
    char const* reason);
 
[[nodiscard]] bool
areCompatible(
    uint256 const& validHash,
    LedgerIndex validIndex,
    ReadView const& testLedger,
    beast::Journal::Stream& s,
    char const* reason);
 
//------------------------------------------------------------------------------
//
// Modifiers
//
//------------------------------------------------------------------------------
 
void
adjustOwnerCount(
    ApplyView& view,
    std::shared_ptr<SLE> const& sle,
    std::int32_t amount,
    beast::Journal j);
 
bool
cdirFirst(
    ReadView const& view,
    uint256 const& root,
    std::shared_ptr<SLE const>& page,
    unsigned int& index,
    uint256& entry);
 
bool
dirFirst(
    ApplyView& view,
    uint256 const& root,
    std::shared_ptr<SLE>& page,
    unsigned int& index,
    uint256& entry);
bool
cdirNext(
    ReadView const& view,
    uint256 const& root,
    std::shared_ptr<SLE const>& page,
    unsigned int& index,
    uint256& entry);
 
bool
dirNext(
    ApplyView& view,
    uint256 const& root,
    std::shared_ptr<SLE>& page,
    unsigned int& index,
    uint256& entry);
[[nodiscard]] std::function<void(SLE::ref)>
describeOwnerDir(AccountID const& account);
 
[[nodiscard]] TER
dirLink(ApplyView& view, AccountID const& owner, std::shared_ptr<SLE>& object);
 
AccountID
pseudoAccountAddress(ReadView const& view, uint256 const& pseudoOwnerKey);
 
[[nodiscard]] Expected<std::shared_ptr<SLE>, TER>
createPseudoAccount(
    ApplyView& view,
    uint256 const& pseudoOwnerKey,
    SField const& ownerField);
 
// Returns true iff sleAcct is a pseudo-account.
//
// Returns false if sleAcct is
// * NOT a pseudo-account OR
// * NOT a ltACCOUNT_ROOT OR
// * null pointer
[[nodiscard]] bool
isPseudoAccount(std::shared_ptr<SLE const> sleAcct);
 
// Returns the list of fields that define an ACCOUNT_ROOT as a pseudo-account if
// set
// Pseudo-account designator fields MUST be maintained by including the
// SField::sMD_PseudoAccount flag in the SField definition. (Don't forget to
// "| SField::sMD_Default"!) The fields do NOT need to be amendment-gated,
// since a non-active amendment will not set any field, by definition.
// Specific properties of a pseudo-account are NOT checked here, that's what
// InvariantCheck is for.
[[nodiscard]] std::vector<SField const*> const&
getPseudoAccountFields();
 
[[nodiscard]] inline bool
isPseudoAccount(ReadView const& view, AccountID accountId)
{
    return isPseudoAccount(view.read(keylet::account(accountId)));
}
 
[[nodiscard]] TER
canAddHolding(ReadView const& view, Asset const& asset);
 
[[nodiscard]] TER
addEmptyHolding(
    ApplyView& view,
    AccountID const& accountID,
    XRPAmount priorBalance,
    Issue const& issue,
    beast::Journal journal);
 
[[nodiscard]] TER
addEmptyHolding(
    ApplyView& view,
    AccountID const& accountID,
    XRPAmount priorBalance,
    MPTIssue const& mptIssue,
    beast::Journal journal);
 
[[nodiscard]] inline TER
addEmptyHolding(
    ApplyView& view,
    AccountID const& accountID,
    XRPAmount priorBalance,
    Asset const& asset,
    beast::Journal journal)
{
    return std::visit(
        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
            return addEmptyHolding(
                view, accountID, priorBalance, issue, journal);
        },
        asset.value());
}
 
[[nodiscard]] TER
authorizeMPToken(
    ApplyView& view,
    XRPAmount const& priorBalance,
    MPTID const& mptIssuanceID,
    AccountID const& account,
    beast::Journal journal,
    std::uint32_t flags = 0,
    std::optional<AccountID> holderID = std::nullopt);
 
// VFALCO NOTE Both STAmount parameters should just
//             be "Amount", a unit-less number.
//
[[nodiscard]] TER
trustCreate(
    ApplyView& view,
    bool const bSrcHigh,
    AccountID const& uSrcAccountID,
    AccountID const& uDstAccountID,
    uint256 const& uIndex,      // --> ripple state entry
    SLE::ref sleAccount,        // --> the account being set.
    bool const bAuth,           // --> authorize account.
    bool const bNoRipple,       // --> others cannot ripple through
    bool const bFreeze,         // --> funds cannot leave
    bool bDeepFreeze,           // --> can neither receive nor send funds
    STAmount const& saBalance,  // --> balance of account being set.
                                // Issuer should be noAccount()
    STAmount const& saLimit,    // --> limit for account being set.
                                // Issuer should be the account being set.
    std::uint32_t uSrcQualityIn,
    std::uint32_t uSrcQualityOut,
    beast::Journal j);
 
[[nodiscard]] TER
removeEmptyHolding(
    ApplyView& view,
    AccountID const& accountID,
    Issue const& issue,
    beast::Journal journal);
 
[[nodiscard]] TER
removeEmptyHolding(
    ApplyView& view,
    AccountID const& accountID,
    MPTIssue const& mptIssue,
    beast::Journal journal);
 
[[nodiscard]] inline TER
removeEmptyHolding(
    ApplyView& view,
    AccountID const& accountID,
    Asset const& asset,
    beast::Journal journal)
{
    return std::visit(
        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
            return removeEmptyHolding(view, accountID, issue, journal);
        },
        asset.value());
}
 
[[nodiscard]] TER
trustDelete(
    ApplyView& view,
    std::shared_ptr<SLE> const& sleRippleState,
    AccountID const& uLowAccountID,
    AccountID const& uHighAccountID,
    beast::Journal j);
 
// [[nodiscard]] // nodiscard commented out so Flow, BookTip and others compile.
TER
offerDelete(ApplyView& view, std::shared_ptr<SLE> const& sle, beast::Journal j);
 
//------------------------------------------------------------------------------
 
//
// Money Transfers
//
 
// Direct send w/o fees:
// - Redeeming IOUs and/or sending sender's own IOUs.
// - Create trust line of needed.
// --> bCheckIssuer : normally require issuer to be involved.
// [[nodiscard]] // nodiscard commented out so DirectStep.cpp compiles.
 
TER
rippleCredit(
    ApplyView& view,
    AccountID const& uSenderID,
    AccountID const& uReceiverID,
    STAmount const& saAmount,
    bool bCheckIssuer,
    beast::Journal j);
 
TER
rippleLockEscrowMPT(
    ApplyView& view,
    AccountID const& uGrantorID,
    STAmount const& saAmount,
    beast::Journal j);
 
TER
rippleUnlockEscrowMPT(
    ApplyView& view,
    AccountID const& uGrantorID,
    AccountID const& uGranteeID,
    STAmount const& netAmount,
    STAmount const& grossAmount,
    beast::Journal j);
 
[[nodiscard]] TER
accountSend(
    ApplyView& view,
    AccountID const& from,
    AccountID const& to,
    STAmount const& saAmount,
    beast::Journal j,
    WaiveTransferFee waiveFee = WaiveTransferFee::No);
 
[[nodiscard]] TER
issueIOU(
    ApplyView& view,
    AccountID const& account,
    STAmount const& amount,
    Issue const& issue,
    beast::Journal j);
 
[[nodiscard]] TER
redeemIOU(
    ApplyView& view,
    AccountID const& account,
    STAmount const& amount,
    Issue const& issue,
    beast::Journal j);
 
[[nodiscard]] TER
transferXRP(
    ApplyView& view,
    AccountID const& from,
    AccountID const& to,
    STAmount const& amount,
    beast::Journal j);
 
/* Check if MPToken (for MPT) or trust line (for IOU) exists:
 * - StrongAuth - before checking if authorization is required
 * - WeakAuth
 *    for MPT - after checking lsfMPTRequireAuth flag
 *    for IOU - do not check if trust line exists
 * - Legacy
 *    for MPT - before checking lsfMPTRequireAuth flag i.e. same as StrongAuth
 *    for IOU - do not check if trust line exists i.e. same as WeakAuth
 */
enum class AuthType { StrongAuth, WeakAuth, Legacy };
 
[[nodiscard]] TER
requireAuth(
    ReadView const& view,
    Issue const& issue,
    AccountID const& account,
    AuthType authType = AuthType::Legacy);
 
[[nodiscard]] TER
requireAuth(
    ReadView const& view,
    MPTIssue const& mptIssue,
    AccountID const& account,
    AuthType authType = AuthType::Legacy,
    int depth = 0);
 
[[nodiscard]] TER inline requireAuth(
    ReadView const& view,
    Asset const& asset,
    AccountID const& account,
    AuthType authType = AuthType::Legacy)
{
    return std::visit(
        [&]<ValidIssueType TIss>(TIss const& issue_) {
            return requireAuth(view, issue_, account, authType);
        },
        asset.value());
}
 
[[nodiscard]] TER
enforceMPTokenAuthorization(
    ApplyView& view,
    MPTID const& mptIssuanceID,
    AccountID const& account,
    XRPAmount const& priorBalance,
    beast::Journal j);
 
[[nodiscard]] TER
canTransfer(
    ReadView const& view,
    MPTIssue const& mptIssue,
    AccountID const& from,
    AccountID const& to);
 
using EntryDeleter = std::function<std::pair<TER, SkipEntry>(
    LedgerEntryType,
    uint256 const&,
    std::shared_ptr<SLE>&)>;
[[nodiscard]] TER
cleanupOnAccountDelete(
    ApplyView& view,
    Keylet const& ownerDirKeylet,
    EntryDeleter const& deleter,
    beast::Journal j,
    std::optional<std::uint16_t> maxNodesToDelete = std::nullopt);
 
[[nodiscard]] TER
deleteAMMTrustLine(
    ApplyView& view,
    std::shared_ptr<SLE> sleState,
    std::optional<AccountID> const& ammAccountID,
    beast::Journal j);
 
// From the perspective of a vault, return the number of shares to give the
// depositor when they deposit a fixed amount of assets. Since shares are MPT
// this number is integral and always truncated in this calculation.
[[nodiscard]] std::optional<STAmount>
assetsToSharesDeposit(
    std::shared_ptr<SLE const> const& vault,
    std::shared_ptr<SLE const> const& issuance,
    STAmount const& assets);
 
// From the perspective of a vault, return the number of assets to take from
// depositor when they receive a fixed amount of shares. Note, since shares are
// MPT, they are always an integral number.
[[nodiscard]] std::optional<STAmount>
sharesToAssetsDeposit(
    std::shared_ptr<SLE const> const& vault,
    std::shared_ptr<SLE const> const& issuance,
    STAmount const& shares);
 
enum class TruncateShares : bool { no = false, yes = true };
 
// From the perspective of a vault, return the number of shares to demand from
// the depositor when they ask to withdraw a fixed amount of assets. Since
// shares are MPT this number is integral, and it will be rounded to nearest
// unless explicitly requested to be truncated instead.
[[nodiscard]] std::optional<STAmount>
assetsToSharesWithdraw(
    std::shared_ptr<SLE const> const& vault,
    std::shared_ptr<SLE const> const& issuance,
    STAmount const& assets,
    TruncateShares truncate = TruncateShares::no);
 
// From the perspective of a vault, return the number of assets to give the
// depositor when they redeem a fixed amount of shares. Note, since shares are
// MPT, they are always an integral number.
[[nodiscard]] std::optional<STAmount>
sharesToAssetsWithdraw(
    std::shared_ptr<SLE const> const& vault,
    std::shared_ptr<SLE const> const& issuance,
    STAmount const& shares);
 
bool
after(NetClock::time_point now, std::uint32_t mark);
 
}  // namespace ripple
 
#endif