// SPDX-License-Identifier: MIT
pragma solidity ^0.8.30;

/// @title IAPN
/// @notice Redemption surface of an Amish Position Note. An APN is an ERC-4626-style share of a
///         single loan: its NAV is the loan's outstanding principal plus the lender's mark-to-market
///         accrued interest (read live from the LoanManager) plus the principal-token cash already
///         repaid into the note. Redeeming burns shares at `NAV / totalSupply` and pays the
///         proportional assets, capped by the cash on hand.
interface IAPN {
    /// @notice The note's net asset value in principal-token base units: illiquid loan claim
    ///         (outstanding principal + lender accrued interest) plus liquid repaid cash.
    function totalAssets() external view returns (uint256);

    /// @notice Assets `shares` are currently worth at the mark-to-market share price (uncapped by
    ///         cash; the actual redeemable amount is bounded by {maxRedeem}).
    function convertToAssets(uint256 shares) external view returns (uint256);

    /// @notice Shares that `assets` are worth at the current share price — the inverse of
    ///         {convertToAssets}. Applied to the cash on hand, it is the share count {maxRedeem} caps to.
    function convertToShares(uint256 assets) external view returns (uint256);

    /// @notice The largest number of shares `owner` can redeem right now — the lesser of their
    ///         balance and the shares whose value the cash on hand can cover.
    function maxRedeem(address owner) external view returns (uint256);

    /// @notice Burn `shares` and receive `shares · NAV / totalSupply` of the principal token. Reverts
    ///         if the payout exceeds the cash on hand (redeem fewer, or wait for more repayments).
    /// @return assets Principal token paid to the caller.
    function redeem(uint256 shares) external returns (uint256 assets);

    /// @notice Redeem the caller's full currently-redeemable amount ({maxRedeem}) in one call.
    /// @return assets Principal token paid to the caller.
    function redeemMax() external returns (uint256 assets);
}