# Interfaces

All interfaces live in `src/interfaces/`. They are the canonical reference for integrators.

## FW (Fira Wrapped)

### IFiraWrappedStandardized

The yield-bearing wrapper token (e.g. USDCFW wrapping USDC into a SisuVault).

```solidity
function deposit(address receiver, address tokenIn, uint256 amountTokenToDeposit, uint256 minSharesOut)
    external payable returns (uint256 amountSharesOut);

function redeem(address receiver, uint256 amountSharesToRedeem, address tokenOut, uint256 minTokenOut, bool burnFromInternalBalance)
    external returns (uint256 amountTokenOut);

function exchangeRate() external view returns (uint256);
function previewDeposit(address tokenIn, uint256 amountTokenToDeposit) external view returns (uint256);
function previewRedeem(address tokenOut, uint256 amountSharesToRedeem) external view returns (uint256);
function claimRewards(address user) external returns (uint256[] memory);
function accruedRewards(address user) external view returns (uint256[] memory);
function getTokensIn() external view returns (address[] memory);
function getTokensOut() external view returns (address[] memory);
function assetInfo() external view returns (AssetType, address, uint8);
```

## Market

### IPMarket

The BT/FW AMM pool. Also an ERC-20 (LP token).

```solidity
function mint(address receiver, uint256 netFwDesired, uint256 netBtDesired)
    external returns (uint256 netLpOut, uint256 netFwUsed, uint256 netBtUsed);

function burn(address receiverFw, address receiverBt, uint256 netLpToBurn)
    external returns (uint256 netFwOut, uint256 netBtOut);

function swapExactBtForFw(address receiver, uint256 exactBtIn, bytes calldata data)
    external returns (uint256 netFwOut, uint256 netFwFee);

function swapFwForExactBt(address receiver, uint256 exactBtOut, bytes calldata data)
    external returns (uint256 netFwIn, uint256 netFwFee);

function readState(address router) external view returns (MarketState memory);
function readTokens() external view returns (IFiraWrappedStandardized, IBondToken, IBCToken);
function observe(uint32[] memory secondsAgos) external view returns (uint216[] memory);
function isExpired() external view returns (bool);
function expiry() external view returns (uint256);
```

### IPMarketFactoryV3

```solidity
function createNewMarket(address BT, int256 scalarRoot, int256 initialAnchor, uint80 lnFeeRateRoot)
    external returns (address market);
function isValidMarket(address market) external view returns (bool);
```

### IPMarketSwapCallback

Implement this if calling FiraMarket swap functions directly (not via Router).

```solidity
function swapCallback(int256 btToAccount, int256 fwToAccount, bytes calldata data) external;
```

## Yield contracts

### IBondToken

Fixed-rate principal token. ERC-20 with restricted mint/burn.

```solidity
function mint(address to, uint256 amount) external;
function burn(address from, uint256 amount) external;
```

### IBCToken (CouponToken)

Floating-yield token with interest accrual. Inherits `IPInterestManagerCT`.

```solidity
function mintBC(address receiverBT, address receiverCT) external returns (uint256 amountBCOut);
function redeemBC(address receiver) external returns (uint256 amountFwOut);
function redeemDueInterestAndRewards(address user, bool redeemInterest, bool redeemRewards)
    external returns (uint256 interestOut, uint256[] memory rewardsOut);
function bcIndexCurrent() external returns (uint256);
function bcIndexStored() external view returns (uint256);
function isExpired() external view returns (bool);
function expiry() external view returns (uint256);
function FW() external view returns (address);
function BT() external view returns (address);
```

### IBCContractFactory

```solidity
function createBCContract(address fw, uint256 expiry) external returns (address BT, address CT);
```

## Router facets

### IPActionSwapBTV3

```solidity
function swapExactBtForFw(address receiver, address market, uint256 exactBtIn, TokenOutput calldata output, LimitOrderData calldata limit)
    external returns (uint256 netFwOut, uint256 netFwFee);

function swapExactFwForBt(address receiver, address market, uint256 exactFwIn, ApproxParams calldata guessBtOut, TokenInput calldata input, LimitOrderData calldata limit)
    external returns (uint256 netBtOut, uint256 netFwFee);
```

### IPActionSwapCTV3

```solidity
function swapExactFwForCt(address receiver, address market, uint256 exactFwIn, TokenInput calldata input, ApproxParams calldata guessCTOut, LimitOrderData calldata limit)
    external returns (uint256 netCtOut, uint256 netFwFee);

function swapExactCtForFw(address receiver, address market, uint256 exactCtIn, TokenOutput calldata output, LimitOrderData calldata limit)
    external returns (uint256 netFwOut, uint256 netFwFee);
```

### IPActionAddRemoveLiqV3

```solidity
function addLiquidityDualFwAndBt(address receiver, address market, TokenInput calldata input, uint256 netBtDesired, uint256 minLpOut)
    external returns (uint256 netLpOut, uint256 netFwUsed, uint256 netBtUsed);

function removeLiquidityDualFwAndBt(address receiver, address market, uint256 netLpToRemove, TokenOutput calldata output, uint256 minBtOut)
    external returns (uint256 netFwOut, uint256 netBtOut);
```

### IPActionMiscV3

```solidity
function mintBcFromFw(address receiver, address CT, uint256 netFwIn, uint256 minBcOut)
    external returns (uint256 netBcOut);

function redeemBcToFw(address receiver, address CT, uint256 netBcIn, TokenOutput calldata output)
    external returns (uint256 netFwOut);

function redeemDueInterestAndRewards(address receiver, address[] calldata CTs, address[] calldata FWs, address[] calldata markets)
    external;

function exitPreExpiry(address receiver, address market, uint256 netBtIn, uint256 netCtIn, uint256 netLpIn, TokenOutput calldata output)
    external returns (uint256 totalFwOut);

function exitPostExpiry(address receiver, address market, uint256 netBtIn, uint256 netCtIn, uint256 netLpIn, TokenOutput calldata output)
    external returns (uint256 totalFwOut);

function multicall(bytes[] calldata data) external payable returns (bytes[] memory results);
```

### IPActionBorrow

```solidity
function borrow(address market, MarketParams calldata marketParams, uint256 amount, uint256 shares, address onBehalf, address receiver)
    external returns (uint256 assetsOut, uint256 sharesOut);

function repay(address market, MarketParams calldata marketParams, uint256 amount, uint256 shares, address onBehalf, bytes calldata data)
    external returns (uint256 assetsRepaid, uint256 sharesRepaid);
```

### IPActionSimple

On-chain approximation variants that avoid the need for off-chain `ApproxParams` computation.

```solidity
function swapExactFwForBtSimple(address receiver, address market, uint256 exactFwIn, uint256 minBtOut)
    external returns (uint256 netBtOut, uint256 netFwFee);

function addLiquiditySingleFwSimple(address receiver, address market, uint256 netFwIn, uint256 minLpOut)
    external returns (uint256 netLpOut);
```

## Shared types (IPAllActionTypeV3)

```solidity
struct TokenInput {
    address tokenIn;
    uint256 netTokenIn;
    address tokenMintFw;
    address firaSwap;
    SwapData swapData;
}

struct TokenOutput {
    address tokenOut;
    uint256 minTokenOut;
    address tokenRedeemFw;
    address firaSwap;
    SwapData swapData;
}

struct ApproxParams {
    uint256 guessMin;
    uint256 guessMax;
    uint256 guessOffchain;
    uint256 maxIteration;
    uint256 eps;
}

struct SwapData {
    SwapType swapType;
    address extRouter;
    bytes extCalldata;
    bool needScale;
}
```

## Utility interfaces

### IRehypothecationModule

```solidity
function rebalance() external;
function phiMin() external view returns (uint256);
function phiMax() external view returns (uint256);
function phiTarget() external view returns (uint256);
```

### ILiquidityInjector

```solidity
function injectLiquidity(uint256 btAmount, uint256 fwAmount) external returns (uint256 lpOut);
function withdrawLiquidity(uint256 lpAmount) external returns (uint256 fwOut, uint256 btOut);
```

### IOracle

```solidity
function price() external view returns (uint256);
```