AMMContext.h

//------------------------------------------------------------------------------
/*
    This file is part of rippled: https://github.com/ripple/rippled
    Copyright (c) 2023 Ripple Labs Inc.
 
    Permission to use, copy, modify, and/or distribute this software for any
    purpose  with  or without fee is hereby granted, provided that the above
    copyright notice and this permission notice appear in all copies.
 
    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
 
#ifndef RIPPLE_APP_PATHS_AMMCONTEXT_H_INCLUDED
#define RIPPLE_APP_PATHS_AMMCONTEXT_H_INCLUDED
 
#include <xrpl/protocol/AccountID.h>
 
#include <cstdint>
 
namespace ripple {
 
class AMMContext
{
public:
    // Restrict number of AMM offers. If this restriction is removed
    // then need to restrict in some other way because AMM offers are
    // not counted in the BookStep offer counter.
    constexpr static std::uint8_t MaxIterations = 30;
 
private:
    // Tx account owner is required to get the AMM trading fee in BookStep
    AccountID account_;
    // true if payment has multiple paths
    bool multiPath_{false};
    // Is true if AMM offer is consumed during a payment engine iteration.
    bool ammUsed_{false};
    // Counter of payment engine iterations with consumed AMM
    std::uint16_t ammIters_{0};
 
public:
    AMMContext(AccountID const& account, bool multiPath)
        : account_(account), multiPath_(multiPath)
    {
    }
    ~AMMContext() = default;
    AMMContext(AMMContext const&) = delete;
    AMMContext&
    operator=(AMMContext const&) = delete;
 
    bool
    multiPath() const
    {
        return multiPath_;
    }
 
    void
    setMultiPath(bool fs)
    {
        multiPath_ = fs;
    }
 
    void
    setAMMUsed()
    {
        ammUsed_ = true;
    }
 
    void
    update()
    {
        if (ammUsed_)
            ++ammIters_;
        ammUsed_ = false;
    }
 
    bool
    maxItersReached() const
    {
        return ammIters_ >= MaxIterations;
    }
 
    std::uint16_t
    curIters() const
    {
        return ammIters_;
    }
 
    AccountID
    account() const
    {
        return account_;
    }
 
    void
    clear()
    {
        ammUsed_ = false;
    }
};
 
}  // namespace ripple
 
#endif  // RIPPLE_APP_PATHS_AMMCONTEXT_H_INCLUDED