#include <xrpl/ledger/helpers/VaultHelpers.h>
//
#include <xrpl/basics/Number.h>
#include <xrpl/protocol/LedgerFormats.h>
#include <xrpl/protocol/st.h>

namespace xrpl {

[[nodiscard]] std::optional<STAmount>
assetsToSharesDeposit(
    std::shared_ptr<SLE const> const& vault,
    MPTokenIssuance const& issuance,
    STAmount const& assets)
{
    XRPL_ASSERT(!assets.negative(), "xrpl::assetsToSharesDeposit : non-negative assets");
    XRPL_ASSERT(
        assets.asset() == vault->at(sfAsset),
        "xrpl::assetsToSharesDeposit : assets and vault match");
    if (assets.negative() || assets.asset() != vault->at(sfAsset))
        return std::nullopt;  // LCOV_EXCL_LINE

    Number const assetTotal = vault->at(sfAssetsTotal);
    STAmount shares{vault->at(sfShareMPTID)};
    if (assetTotal == 0)
    {
        return STAmount{
            shares.asset(),
            Number(assets.mantissa(), assets.exponent() + vault->at(sfScale)).truncate()};
    }

    Number const shareTotal = issuance->at(sfOutstandingAmount);
    shares = ((shareTotal * assets) / assetTotal).truncate();
    return shares;
}

[[nodiscard]] std::optional<STAmount>
sharesToAssetsDeposit(
    std::shared_ptr<SLE const> const& vault,
    MPTokenIssuance const& issuance,
    STAmount const& shares)
{
    XRPL_ASSERT(!shares.negative(), "xrpl::sharesToAssetsDeposit : non-negative shares");
    XRPL_ASSERT(
        shares.asset() == vault->at(sfShareMPTID),
        "xrpl::sharesToAssetsDeposit : shares and vault match");
    if (shares.negative() || shares.asset() != vault->at(sfShareMPTID))
        return std::nullopt;  // LCOV_EXCL_LINE

    Number const assetTotal = vault->at(sfAssetsTotal);
    STAmount assets{vault->at(sfAsset)};
    if (assetTotal == 0)
    {
        return STAmount{
            assets.asset(), shares.mantissa(), shares.exponent() - vault->at(sfScale), false};
    }

    Number const shareTotal = issuance->at(sfOutstandingAmount);
    assets = (assetTotal * shares) / shareTotal;
    return assets;
}

[[nodiscard]] std::optional<STAmount>
assetsToSharesWithdraw(
    std::shared_ptr<SLE const> const& vault,
    MPTokenIssuance const& issuance,
    STAmount const& assets,
    TruncateShares truncate)
{
    XRPL_ASSERT(!assets.negative(), "xrpl::assetsToSharesWithdraw : non-negative assets");
    XRPL_ASSERT(
        assets.asset() == vault->at(sfAsset),
        "xrpl::assetsToSharesWithdraw : assets and vault match");
    if (assets.negative() || assets.asset() != vault->at(sfAsset))
        return std::nullopt;  // LCOV_EXCL_LINE

    Number assetTotal = vault->at(sfAssetsTotal);
    assetTotal -= vault->at(sfLossUnrealized);
    STAmount shares{vault->at(sfShareMPTID)};
    if (assetTotal == 0)
        return shares;
    Number const shareTotal = issuance->at(sfOutstandingAmount);
    Number result = (shareTotal * assets) / assetTotal;
    if (truncate == TruncateShares::yes)
        result = result.truncate();
    shares = result;
    return shares;
}

[[nodiscard]] std::optional<STAmount>
sharesToAssetsWithdraw(
    std::shared_ptr<SLE const> const& vault,
    MPTokenIssuance const& issuance,
    STAmount const& shares)
{
    XRPL_ASSERT(!shares.negative(), "xrpl::sharesToAssetsDeposit : non-negative shares");
    XRPL_ASSERT(
        shares.asset() == vault->at(sfShareMPTID),
        "xrpl::sharesToAssetsWithdraw : shares and vault match");
    if (shares.negative() || shares.asset() != vault->at(sfShareMPTID))
        return std::nullopt;  // LCOV_EXCL_LINE

    Number assetTotal = vault->at(sfAssetsTotal);
    assetTotal -= vault->at(sfLossUnrealized);
    STAmount assets{vault->at(sfAsset)};
    if (assetTotal == 0)
        return assets;
    Number const shareTotal = issuance->at(sfOutstandingAmount);
    assets = (assetTotal * shares) / shareTotal;
    return assets;
}

}  // namespace xrpl