AMMLiquidity.h

#pragma once
 
#include <xrpl/basics/Number.h>
#include <xrpl/beast/utility/Journal.h>
#include <xrpl/ledger/ReadView.h>
#include <xrpl/protocol/AccountID.h>
#include <xrpl/protocol/Concepts.h>
#include <xrpl/protocol/Quality.h>
#include <xrpl/tx/transactors/dex/AMMContext.h>
 
#include <cstdint>
#include <optional>
 
namespace xrpl {
 
template <StepAmount TIn, StepAmount TOut>
class AMMOffer;

template <typename TIn, typename TOut>
class AMMLiquidity
{
private:
    inline static Number const kInitialFibSeqPct = Number(5) / 20000;
    AMMContext& ammContext_;
    AccountID const ammAccountID_;
    std::uint32_t const tradingFee_;
    Asset const assetIn_;
    Asset const assetOut_;
    // Initial AMM pool balances
    TAmounts<TIn, TOut> const initialBalances_;
    beast::Journal const j_;
 
public:
    AMMLiquidity(
        ReadView const& view,
        AccountID const& ammAccountID,
        std::uint32_t tradingFee,
        Asset const& in,
        Asset const& out,
        AMMContext& ammContext,
        beast::Journal j);
    ~AMMLiquidity() = default;
    AMMLiquidity(AMMLiquidity const&) = delete;
    AMMLiquidity&
    operator=(AMMLiquidity const&) = delete;

    [[nodiscard]] std::optional<AMMOffer<TIn, TOut>>
    getOffer(ReadView const& view, std::optional<Quality> const& clobQuality) const;
 
    [[nodiscard]] AccountID const&
    ammAccount() const
    {
        return ammAccountID_;
    }
 
    [[nodiscard]] bool
    multiPath() const
    {
        return ammContext_.multiPath();
    }
 
    [[nodiscard]] std::uint32_t
    tradingFee() const
    {
        return tradingFee_;
    }
 
    [[nodiscard]] AMMContext&
    context() const
    {
        return ammContext_;
    }
 
    [[nodiscard]] Asset const&
    assetIn() const
    {
        return assetIn_;
    }
 
    [[nodiscard]] Asset const&
    assetOut() const
    {
        return assetOut_;
    }
 
private:
    [[nodiscard]] TAmounts<TIn, TOut>
    fetchBalances(ReadView const& view) const;

    [[nodiscard]] TAmounts<TIn, TOut>
    generateFibSeqOffer(TAmounts<TIn, TOut> const& balances) const;

    [[nodiscard]] std::optional<AMMOffer<TIn, TOut>>
    maxOffer(TAmounts<TIn, TOut> const& balances) const;
};
 
}  // namespace xrpl