// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 amount);

    event Approval(address indexed owner, address indexed spender, uint256 amount);

    /*//////////////////////////////////////////////////////////////
                            METADATA STORAGE
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    uint8 public immutable decimals;

    /*//////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 public totalSupply;

    mapping(address => uint256) public balanceOf;

    mapping(address => mapping(address => uint256)) public allowance;

    /*//////////////////////////////////////////////////////////////
                            EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 internal immutable INITIAL_CHAIN_ID;

    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;

    mapping(address => uint256) public nonces;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals
    ) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;

        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }

    /*//////////////////////////////////////////////////////////////
                               ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;

        emit Approval(msg.sender, spender, amount);

        return true;
    }

    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(msg.sender, to, amount);

        return true;
    }

    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.

        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;

        balanceOf[from] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(from, to, amount);

        return true;
    }

    /*//////////////////////////////////////////////////////////////
                             EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");

        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            address recoveredAddress = ecrecover(
                keccak256(
                    abi.encodePacked(
                        "\x19\x01",
                        DOMAIN_SEPARATOR(),
                        keccak256(
                            abi.encode(
                                keccak256(
                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                ),
                                owner,
                                spender,
                                value,
                                nonces[owner]++,
                                deadline
                            )
                        )
                    )
                ),
                v,
                r,
                s
            );

            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");

            allowance[recoveredAddress][spender] = value;
        }

        emit Approval(owner, spender, value);
    }

    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }

    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;

        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }

        emit Transfer(from, address(0), amount);
    }
}

// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

import {ERC20} from "../tokens/ERC20.sol";
import {SafeTransferLib} from "../utils/SafeTransferLib.sol";
import {FixedPointMathLib} from "../utils/FixedPointMathLib.sol";

/// @notice Minimal ERC4626 tokenized Vault implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/mixins/ERC4626.sol)
abstract contract ERC4626 is ERC20 {
    using SafeTransferLib for ERC20;
    using FixedPointMathLib for uint256;

    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Deposit(address indexed caller, address indexed owner, uint256 assets, uint256 shares);

    event Withdraw(
        address indexed caller,
        address indexed receiver,
        address indexed owner,
        uint256 assets,
        uint256 shares
    );

    /*//////////////////////////////////////////////////////////////
                               IMMUTABLES
    //////////////////////////////////////////////////////////////*/

    ERC20 public immutable asset;

    constructor(
        ERC20 _asset,
        string memory _name,
        string memory _symbol
    ) ERC20(_name, _symbol, _asset.decimals()) {
        asset = _asset;
    }

    /*//////////////////////////////////////////////////////////////
                        DEPOSIT/WITHDRAWAL LOGIC
    //////////////////////////////////////////////////////////////*/

    function deposit(uint256 assets, address receiver) public virtual returns (uint256 shares) {
        // Check for rounding error since we round down in previewDeposit.
        require((shares = previewDeposit(assets)) != 0, "ZERO_SHARES");

        // Need to transfer before minting or ERC777s could reenter.
        asset.safeTransferFrom(msg.sender, address(this), assets);

        _mint(receiver, shares);

        emit Deposit(msg.sender, receiver, assets, shares);

        afterDeposit(assets, shares);
    }

    function mint(uint256 shares, address receiver) public virtual returns (uint256 assets) {
        assets = previewMint(shares); // No need to check for rounding error, previewMint rounds up.

        // Need to transfer before minting or ERC777s could reenter.
        asset.safeTransferFrom(msg.sender, address(this), assets);

        _mint(receiver, shares);

        emit Deposit(msg.sender, receiver, assets, shares);

        afterDeposit(assets, shares);
    }

    function withdraw(
        uint256 assets,
        address receiver,
        address owner
    ) public virtual returns (uint256 shares) {
        shares = previewWithdraw(assets); // No need to check for rounding error, previewWithdraw rounds up.

        if (msg.sender != owner) {
            uint256 allowed = allowance[owner][msg.sender]; // Saves gas for limited approvals.

            if (allowed != type(uint256).max) allowance[owner][msg.sender] = allowed - shares;
        }

        beforeWithdraw(assets, shares);

        _burn(owner, shares);

        emit Withdraw(msg.sender, receiver, owner, assets, shares);

        asset.safeTransfer(receiver, assets);
    }

    function redeem(
        uint256 shares,
        address receiver,
        address owner
    ) public virtual returns (uint256 assets) {
        if (msg.sender != owner) {
            uint256 allowed = allowance[owner][msg.sender]; // Saves gas for limited approvals.

            if (allowed != type(uint256).max) allowance[owner][msg.sender] = allowed - shares;
        }

        // Check for rounding error since we round down in previewRedeem.
        require((assets = previewRedeem(shares)) != 0, "ZERO_ASSETS");

        beforeWithdraw(assets, shares);

        _burn(owner, shares);

        emit Withdraw(msg.sender, receiver, owner, assets, shares);

        asset.safeTransfer(receiver, assets);
    }

    /*//////////////////////////////////////////////////////////////
                            ACCOUNTING LOGIC
    //////////////////////////////////////////////////////////////*/

    function totalAssets() public view virtual returns (uint256);

    function convertToShares(uint256 assets) public view virtual returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? assets : assets.mulDivDown(supply, totalAssets());
    }

    function convertToAssets(uint256 shares) public view virtual returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? shares : shares.mulDivDown(totalAssets(), supply);
    }

    function previewDeposit(uint256 assets) public view virtual returns (uint256) {
        return convertToShares(assets);
    }

    function previewMint(uint256 shares) public view virtual returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? shares : shares.mulDivUp(totalAssets(), supply);
    }

    function previewWithdraw(uint256 assets) public view virtual returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? assets : assets.mulDivUp(supply, totalAssets());
    }

    function previewRedeem(uint256 shares) public view virtual returns (uint256) {
        return convertToAssets(shares);
    }

    /*//////////////////////////////////////////////////////////////
                     DEPOSIT/WITHDRAWAL LIMIT LOGIC
    //////////////////////////////////////////////////////////////*/

    function maxDeposit(address) public view virtual returns (uint256) {
        return type(uint256).max;
    }

    function maxMint(address) public view virtual returns (uint256) {
        return type(uint256).max;
    }

    function maxWithdraw(address owner) public view virtual returns (uint256) {
        return convertToAssets(balanceOf[owner]);
    }

    function maxRedeem(address owner) public view virtual returns (uint256) {
        return balanceOf[owner];
    }

    /*//////////////////////////////////////////////////////////////
                          INTERNAL HOOKS LOGIC
    //////////////////////////////////////////////////////////////*/

    function beforeWithdraw(uint256 assets, uint256 shares) internal virtual {}

    function afterDeposit(uint256 assets, uint256 shares) internal virtual {}
}

// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Arithmetic library with operations for fixed-point numbers.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/FixedPointMathLib.sol)
/// @author Inspired by USM (https://github.com/usmfum/USM/blob/master/contracts/WadMath.sol)
library FixedPointMathLib {
    /*//////////////////////////////////////////////////////////////
                    SIMPLIFIED FIXED POINT OPERATIONS
    //////////////////////////////////////////////////////////////*/

    uint256 internal constant MAX_UINT256 = 2**256 - 1;

    uint256 internal constant WAD = 1e18; // The scalar of ETH and most ERC20s.

    function mulWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivDown(x, y, WAD); // Equivalent to (x * y) / WAD rounded down.
    }

    function mulWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivUp(x, y, WAD); // Equivalent to (x * y) / WAD rounded up.
    }

    function divWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivDown(x, WAD, y); // Equivalent to (x * WAD) / y rounded down.
    }

    function divWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
        return mulDivUp(x, WAD, y); // Equivalent to (x * WAD) / y rounded up.
    }

    /*//////////////////////////////////////////////////////////////
                    LOW LEVEL FIXED POINT OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function mulDivDown(
        uint256 x,
        uint256 y,
        uint256 denominator
    ) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Equivalent to require(denominator != 0 && (y == 0 || x <= type(uint256).max / y))
            if iszero(mul(denominator, iszero(mul(y, gt(x, div(MAX_UINT256, y)))))) {
                revert(0, 0)
            }

            // Divide x * y by the denominator.
            z := div(mul(x, y), denominator)
        }
    }

    function mulDivUp(
        uint256 x,
        uint256 y,
        uint256 denominator
    ) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Equivalent to require(denominator != 0 && (y == 0 || x <= type(uint256).max / y))
            if iszero(mul(denominator, iszero(mul(y, gt(x, div(MAX_UINT256, y)))))) {
                revert(0, 0)
            }

            // If x * y modulo the denominator is strictly greater than 0,
            // 1 is added to round up the division of x * y by the denominator.
            z := add(gt(mod(mul(x, y), denominator), 0), div(mul(x, y), denominator))
        }
    }

    function rpow(
        uint256 x,
        uint256 n,
        uint256 scalar
    ) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            switch x
            case 0 {
                switch n
                case 0 {
                    // 0 ** 0 = 1
                    z := scalar
                }
                default {
                    // 0 ** n = 0
                    z := 0
                }
            }
            default {
                switch mod(n, 2)
                case 0 {
                    // If n is even, store scalar in z for now.
                    z := scalar
                }
                default {
                    // If n is odd, store x in z for now.
                    z := x
                }

                // Shifting right by 1 is like dividing by 2.
                let half := shr(1, scalar)

                for {
                    // Shift n right by 1 before looping to halve it.
                    n := shr(1, n)
                } n {
                    // Shift n right by 1 each iteration to halve it.
                    n := shr(1, n)
                } {
                    // Revert immediately if x ** 2 would overflow.
                    // Equivalent to iszero(eq(div(xx, x), x)) here.
                    if shr(128, x) {
                        revert(0, 0)
                    }

                    // Store x squared.
                    let xx := mul(x, x)

                    // Round to the nearest number.
                    let xxRound := add(xx, half)

                    // Revert if xx + half overflowed.
                    if lt(xxRound, xx) {
                        revert(0, 0)
                    }

                    // Set x to scaled xxRound.
                    x := div(xxRound, scalar)

                    // If n is even:
                    if mod(n, 2) {
                        // Compute z * x.
                        let zx := mul(z, x)

                        // If z * x overflowed:
                        if iszero(eq(div(zx, x), z)) {
                            // Revert if x is non-zero.
                            if iszero(iszero(x)) {
                                revert(0, 0)
                            }
                        }

                        // Round to the nearest number.
                        let zxRound := add(zx, half)

                        // Revert if zx + half overflowed.
                        if lt(zxRound, zx) {
                            revert(0, 0)
                        }

                        // Return properly scaled zxRound.
                        z := div(zxRound, scalar)
                    }
                }
            }
        }
    }

    /*//////////////////////////////////////////////////////////////
                        GENERAL NUMBER UTILITIES
    //////////////////////////////////////////////////////////////*/

    function sqrt(uint256 x) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            let y := x // We start y at x, which will help us make our initial estimate.

            z := 181 // The "correct" value is 1, but this saves a multiplication later.

            // This segment is to get a reasonable initial estimate for the Babylonian method. With a bad
            // start, the correct # of bits increases ~linearly each iteration instead of ~quadratically.

            // We check y >= 2^(k + 8) but shift right by k bits
            // each branch to ensure that if x >= 256, then y >= 256.
            if iszero(lt(y, 0x10000000000000000000000000000000000)) {
                y := shr(128, y)
                z := shl(64, z)
            }
            if iszero(lt(y, 0x1000000000000000000)) {
                y := shr(64, y)
                z := shl(32, z)
            }
            if iszero(lt(y, 0x10000000000)) {
                y := shr(32, y)
                z := shl(16, z)
            }
            if iszero(lt(y, 0x1000000)) {
                y := shr(16, y)
                z := shl(8, z)
            }

            // Goal was to get z*z*y within a small factor of x. More iterations could
            // get y in a tighter range. Currently, we will have y in [256, 256*2^16).
            // We ensured y >= 256 so that the relative difference between y and y+1 is small.
            // That's not possible if x < 256 but we can just verify those cases exhaustively.

            // Now, z*z*y <= x < z*z*(y+1), and y <= 2^(16+8), and either y >= 256, or x < 256.
            // Correctness can be checked exhaustively for x < 256, so we assume y >= 256.
            // Then z*sqrt(y) is within sqrt(257)/sqrt(256) of sqrt(x), or about 20bps.

            // For s in the range [1/256, 256], the estimate f(s) = (181/1024) * (s+1) is in the range
            // (1/2.84 * sqrt(s), 2.84 * sqrt(s)), with largest error when s = 1 and when s = 256 or 1/256.

            // Since y is in [256, 256*2^16), let a = y/65536, so that a is in [1/256, 256). Then we can estimate
            // sqrt(y) using sqrt(65536) * 181/1024 * (a + 1) = 181/4 * (y + 65536)/65536 = 181 * (y + 65536)/2^18.

            // There is no overflow risk here since y < 2^136 after the first branch above.
            z := shr(18, mul(z, add(y, 65536))) // A mul() is saved from starting z at 181.

            // Given the worst case multiplicative error of 2.84 above, 7 iterations should be enough.
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))
            z := shr(1, add(z, div(x, z)))

            // If x+1 is a perfect square, the Babylonian method cycles between
            // floor(sqrt(x)) and ceil(sqrt(x)). This statement ensures we return floor.
            // See: https://en.wikipedia.org/wiki/Integer_square_root#Using_only_integer_division
            // Since the ceil is rare, we save gas on the assignment and repeat division in the rare case.
            // If you don't care whether the floor or ceil square root is returned, you can remove this statement.
            z := sub(z, lt(div(x, z), z))
        }
    }

    function unsafeMod(uint256 x, uint256 y) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Mod x by y. Note this will return
            // 0 instead of reverting if y is zero.
            z := mod(x, y)
        }
    }

    function unsafeDiv(uint256 x, uint256 y) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            // Divide x by y. Note this will return
            // 0 instead of reverting if y is zero.
            r := div(x, y)
        }
    }

    function unsafeDivUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            // Add 1 to x * y if x % y > 0. Note this will
            // return 0 instead of reverting if y is zero.
            z := add(gt(mod(x, y), 0), div(x, y))
        }
    }
}

/**
 * Created by Pragma Labs
 * SPDX-License-Identifier: MIT
 */
pragma solidity ^0.8.13;

interface IGuardian {
    /**
     * @notice Returns if Withdrawals are paused or not.
     * @return bool indicating if Withdrawals are paused or not.
     */
    function withdrawPaused() external view returns (bool);

    /**
     * @notice Returns if Deposits are paused or not.
     * @return bool indicating if Deposits are paused or not.
     */
    function depositPaused() external view returns (bool);
}

/**
 * Created by Pragma Labs
 * SPDX-License-Identifier: MIT
 */
pragma solidity ^0.8.13;

import { ERC20 } from "../../lib/solmate/src/tokens/ERC20.sol";

interface ILendingPool {
    /**
     * @notice returns the supply cap of the Lending Pool.
     * @return supplyCap The supply cap of the Lending Pool.
     */
    function supplyCap() external view returns (uint128);

    /**
     * @notice returns the total realised liquidity of the Lending Pool.
     * @return totalRealisedLiquidity The total realised liquidity of the Lending Pool.
     */
    function totalRealisedLiquidity() external view returns (uint128);

    /**
     * @notice Deposit assets in the Lending Pool.
     * @param assets The amount of assets of the underlying ERC-20 token being deposited.
     * @param from The address of the Liquidity Provider who deposits the underlying ERC-20 token via a Tranche.
     */
    function depositInLendingPool(uint256 assets, address from) external;

    /**
     * @notice Withdraw assets from the Lending Pool.
     * @param assets The amount of assets of the underlying ERC-20 tokens being withdrawn.
     * @param receiver The address of the receiver of the underlying ERC-20 tokens.
     */
    function withdrawFromLendingPool(uint256 assets, address receiver) external;

    /**
     * @notice Returns the redeemable amount of liquidity in the underlying asset of an address.
     * @param owner The address of the liquidity provider.
     * @return assets The redeemable amount of liquidity in the underlying asset.
     */
    function liquidityOf(address owner) external view returns (uint256);

    /**
     * @notice liquidityOf, but syncs the unrealised interest first.
     * @param owner The address of the liquidity provider.
     * @return assets The redeemable amount of liquidity in the underlying asset.
     */
    function liquidityOfAndSync(address owner) external returns (uint256);

    /**
     * @notice Calculates the unrealised debt (interests).
     * @return unrealisedDebt The unrealised debt.
     */
    function calcUnrealisedDebt() external view returns (uint256);
}

/**
 * Created by Pragma Labs
 * SPDX-License-Identifier: MIT
 */
pragma solidity ^0.8.13;

interface ITranche {
    /**
     * @notice Locks the tranche in case all liquidity of the tranche is written of due to bad debt.
     */
    function lock() external;

    /**
     * @notice Locks the tranche while an auction is in progress.
     * @param auctionInProgress Flag indicating if there are auctions in progress.
     */
    function setAuctionInProgress(bool auctionInProgress) external;
}

// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Simple single owner authorization mixin.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/auth/Owned.sol)
abstract contract Owned {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event OwnershipTransferred(address indexed user, address indexed newOwner);

    /*//////////////////////////////////////////////////////////////
                            OWNERSHIP STORAGE
    //////////////////////////////////////////////////////////////*/

    address public owner;

    modifier onlyOwner() virtual {
        require(msg.sender == owner, "UNAUTHORIZED");

        _;
    }

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(address _owner) {
        owner = _owner;

        emit OwnershipTransferred(address(0), _owner);
    }

    /*//////////////////////////////////////////////////////////////
                             OWNERSHIP LOGIC
    //////////////////////////////////////////////////////////////*/

    function transferOwnership(address newOwner) public virtual onlyOwner {
        owner = newOwner;

        emit OwnershipTransferred(msg.sender, newOwner);
    }
}

// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

import {ERC20} from "../tokens/ERC20.sol";

/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
/// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
library SafeTransferLib {
    /*//////////////////////////////////////////////////////////////
                             ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferETH(address to, uint256 amount) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Transfer the ETH and store if it succeeded or not.
            success := call(gas(), to, amount, 0, 0, 0, 0)
        }

        require(success, "ETH_TRANSFER_FAILED");
    }

    /*//////////////////////////////////////////////////////////////
                            ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferFrom(
        ERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), from) // Append the "from" argument.
            mstore(add(freeMemoryPointer, 36), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
            )
        }

        require(success, "TRANSFER_FROM_FAILED");
    }

    function safeTransfer(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "TRANSFER_FAILED");
    }

    function safeApprove(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "APPROVE_FAILED");
    }
}

/**
 * Created by Pragma Labs
 * SPDX-License-Identifier: BUSL-1.1
 */
pragma solidity ^0.8.13;

import { Owned } from "../lib/solmate/src/auth/Owned.sol";
import { ERC4626 } from "../lib/solmate/src/mixins/ERC4626.sol";
import { ILendingPool } from "./interfaces/ILendingPool.sol";
import { FixedPointMathLib } from "../lib/solmate/src/utils/FixedPointMathLib.sol";
import { ITranche } from "./interfaces/ITranche.sol";
import { IGuardian } from "./interfaces/IGuardian.sol";

/**
 * @title Tranche
 * @author Pragma Labs
 * @notice The Tranche contract allows for lending of a specified ERC20 token, managed by a lending pool.
 * @dev Protocol is according the ERC4626 standard, with a certain ERC20 as underlying
 * @dev Implementation not vulnerable to ERC4626 inflation attacks,
 * since totalAssets() cannot be manipulated by first minter when total amount of shares are low.
 * For more information, see https://github.com/OpenZeppelin/openzeppelin-contracts/issues/3706
 */
contract Tranche is ITranche, ERC4626, Owned {
    using FixedPointMathLib for uint256;

    ILendingPool public immutable lendingPool;

    /* //////////////////////////////////////////////////////////////
                                STORAGE
    ////////////////////////////////////////////////////////////// */

    // Flag indicating if the Tranche is locked or not.
    bool public locked;
    // Flag indicating if there are ongoing auctions or not.
    bool public auctionInProgress;

    /* //////////////////////////////////////////////////////////////
                                EVENTS
    ////////////////////////////////////////////////////////////// */

    event LockSet(bool status);
    event AuctionFlagSet(bool status);

    /* //////////////////////////////////////////////////////////////
                                MODIFIERS
    ////////////////////////////////////////////////////////////// */

    modifier notLocked() {
        require(!locked, "TRANCHE: LOCKED");
        _;
    }

    /**
     * @dev Certain actions (depositing and withdrawing) can be halted on the most junior tranche while auctions are in progress.
     * This prevents frontrunning both in the case there is bad debt (by pulling out the tranche before the bad debt is settled),
     * as in the case there are big payouts to the LPs (mitigate Just In Time attacks, where MEV bots front-run the payout of
     * Liquidation penalties to the most junior tranche and withdraw immediately after).
     */
    modifier notDuringAuction() {
        require(!auctionInProgress, "TRANCHE: AUCTION IN PROGRESS");
        _;
    }

    /* //////////////////////////////////////////////////////////////
                                CONSTRUCTOR
    ////////////////////////////////////////////////////////////// */

    /**
     * @notice The constructor for a tranche.
     * @param lendingPool_ the Lending Pool of the underlying ERC-20 token, with the lending logic.
     * @param prefix_ The prefix of the contract name (eg. Senior -> Mezzanine -> Junior).
     * @param prefixSymbol_ The prefix of the contract symbol (eg. SR  -> MZ -> JR).
     * @dev The name and symbol of the tranche are automatically generated, based on the name and symbol of the underlying token.
     */
    constructor(address lendingPool_, string memory prefix_, string memory prefixSymbol_)
        ERC4626(
            ERC4626(address(lendingPool_)).asset(),
            string(abi.encodePacked(prefix_, " Arcadia ", ERC4626(lendingPool_).asset().name())),
            string(abi.encodePacked(prefixSymbol_, "arc", ERC4626(lendingPool_).asset().symbol()))
        )
        Owned(msg.sender)
    {
        lendingPool = ILendingPool(lendingPool_);
    }

    /*//////////////////////////////////////////////////////////////
                        LOCKING LOGIC
    //////////////////////////////////////////////////////////////*/

    /**
     * @notice Locks the tranche in case all liquidity of the tranche is written off due to bad debt.
     * @dev Only the Lending Pool can call this function, only trigger is a severe default event.
     */
    function lock() external {
        require(msg.sender == address(lendingPool), "T_L: UNAUTHORIZED");
        locked = true;
        auctionInProgress = false;

        emit LockSet(true);
        emit AuctionFlagSet(false);
    }

    /**
     * @notice Unlocks the tranche.
     * @dev Only the Owner can call this function, since tranches are locked due to complete defaults,
     * This function will only be called to partially refund existing share-holders after a default.
     */
    function unLock() external onlyOwner {
        locked = false;

        emit LockSet(false);
    }

    /**
     * @notice Locks the tranche when an auction is in progress.
     * @param auctionInProgress_ Flag indicating if there are auctions in progress.
     * @dev Only the Lending Pool can call this function.
     * This function is to make sure no JIT liquidity is provided during a positive auction,
     * and that no liquidity can be withdrawn during a negative auction.
     */
    function setAuctionInProgress(bool auctionInProgress_) external {
        require(msg.sender == address(lendingPool), "T_SAIP: UNAUTHORIZED");
        auctionInProgress = auctionInProgress_;

        emit AuctionFlagSet(auctionInProgress_);
    }

    /*//////////////////////////////////////////////////////////////
                        DEPOSIT/WITHDRAWAL LOGIC
    //////////////////////////////////////////////////////////////*/

    /**
     * @notice Modification of the standard ERC-4626 deposit implementation.
     * @param assets The amount of assets of the underlying ERC-20 token being deposited.
     * @param receiver The address that receives the minted shares.
     * @return shares The amount of shares minted.
     * @dev This contract does not directly transfer the underlying assets from the sender to the receiver.
     * Instead it calls the deposit of the Lending Pool which calls the transferFrom of the underlying assets.
     * Hence the sender should not give this contract an allowance to transfer the underlying asset but the Lending Pool.
     */
    function deposit(uint256 assets, address receiver)
        public
        override
        notLocked
        notDuringAuction
        returns (uint256 shares)
    {
        // Check for rounding error since we round down in previewDeposit.
        require((shares = previewDepositAndSync(assets)) != 0, "T_D: ZERO_SHARES");

        // Need to transfer (via lendingPool.depositInLendingPool()) before minting or ERC777s could reenter.
        lendingPool.depositInLendingPool(assets, msg.sender);

        _mint(receiver, shares);

        emit Deposit(msg.sender, receiver, assets, shares);
    }

    /**
     * @notice Modification of the standard ERC-4626 mint implementation.
     * @param shares The amount of shares minted.
     * @param receiver The address that receives the minted shares.
     * @return assets The corresponding amount of assets of the underlying ERC-20 token being deposited.
     * @dev This contract does not directly transfers the underlying assets from the sender to the receiver.
     * Instead it calls the deposit of the Lending Pool which calls the transferFrom of the underlying assets.
     * Hence the sender should not give this contract an allowance to transfer the underlying asset but the Lending Pool.
     */
    function mint(uint256 shares, address receiver)
        public
        override
        notLocked
        notDuringAuction
        returns (uint256 assets)
    {
        assets = previewMintAndSync(shares); // No need to check for rounding error, previewMint rounds up.

        // Need to transfer (via lendingPool.depositInLendingPool()) before minting or ERC777s could reenter.
        lendingPool.depositInLendingPool(assets, msg.sender);

        _mint(receiver, shares);

        emit Deposit(msg.sender, receiver, assets, shares);
    }

    /**
     * @notice Modification of the standard ERC-4626 withdraw implementation.
     * @param assets The amount of assets of the underlying ERC-20 token being withdrawn.
     * @param receiver The address of the receiver of the underlying ERC-20 tokens.
     * @param owner_ The address of the owner of the assets being withdrawn.
     * @return shares The corresponding amount of shares redeemed.
     */
    function withdraw(uint256 assets, address receiver, address owner_)
        public
        override
        notLocked
        notDuringAuction
        returns (uint256 shares)
    {
        shares = previewWithdrawAndSync(assets); // No need to check for rounding error, previewWithdraw rounds up.

        if (msg.sender != owner_) {
            uint256 allowed = allowance[owner_][msg.sender]; // Saves gas for limited approvals.

            if (allowed != type(uint256).max) {
                allowance[owner_][msg.sender] = allowed - shares;
            }
        }

        _burn(owner_, shares);

        emit Withdraw(msg.sender, receiver, owner_, assets, shares);

        lendingPool.withdrawFromLendingPool(assets, receiver);
    }

    /**
     * @notice Modification of the standard ERC-4626 redeem implementation.
     * @param shares the amount of shares being redeemed.
     * @param receiver The address of the receiver of the underlying ERC-20 tokens.
     * @param owner_ The address of the owner of the shares being redeemed.
     * @return assets The corresponding amount of assets withdrawn.
     */
    function redeem(uint256 shares, address receiver, address owner_)
        public
        override
        notLocked
        notDuringAuction
        returns (uint256 assets)
    {
        if (msg.sender != owner_) {
            uint256 allowed = allowance[owner_][msg.sender]; // Saves gas for limited approvals.

            if (allowed != type(uint256).max) {
                allowance[owner_][msg.sender] = allowed - shares;
            }
        }

        // Check for rounding error since we round down in previewRedeem.
        require((assets = previewRedeemAndSync(shares)) != 0, "T_R: ZERO_ASSETS");

        _burn(owner_, shares);

        emit Withdraw(msg.sender, receiver, owner_, assets, shares);

        lendingPool.withdrawFromLendingPool(assets, receiver);
    }

    /*//////////////////////////////////////////////////////////////
                            ACCOUNTING LOGIC
    //////////////////////////////////////////////////////////////*/

    /**
     * @notice Returns the total amount of underlying assets, to which liquidity providers have a claim.
     * @return assets The total amount of underlying assets, to which liquidity providers have a claim.
     * @dev The Liquidity Pool does the accounting of the outstanding claim on liquidity per tranche.
     */
    function totalAssets() public view override returns (uint256 assets) {
        assets = lendingPool.liquidityOf(address(this));
    }

    /**
     * @dev Modification of totalAssets() where interests are realised (state modification).
     */
    function totalAssetsAndSync() public returns (uint256 assets) {
        assets = lendingPool.liquidityOfAndSync(address(this));
    }

    /**
     * @dev Modification of convertToShares() where interests are realised (state modification).
     */
    function convertToSharesAndSync(uint256 assets) public returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? assets : assets.mulDivDown(supply, totalAssetsAndSync());
    }

    /**
     * @dev Modification of convertToAssets() where interests are realised (state modification).
     */
    function convertToAssetsAndSync(uint256 shares) public returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? shares : shares.mulDivDown(totalAssetsAndSync(), supply);
    }

    /**
     * @dev Modification of previewDeposit() where interests are realised (state modification).
     */
    function previewDepositAndSync(uint256 assets) public returns (uint256) {
        return convertToSharesAndSync(assets);
    }

    /**
     * @dev Modification of previewMint() where interests are realised (state modification).
     */
    function previewMintAndSync(uint256 shares) public returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? shares : shares.mulDivUp(totalAssetsAndSync(), supply);
    }

    /**
     * @dev Modification of previewWithdraw() where interests are realised (state modification).
     */
    function previewWithdrawAndSync(uint256 assets) public returns (uint256) {
        uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero.

        return supply == 0 ? assets : assets.mulDivUp(supply, totalAssetsAndSync());
    }

    /**
     * @dev Modification of previewRedeem() where interests are realised (state modification).
     */
    function previewRedeemAndSync(uint256 shares) public returns (uint256) {
        return convertToAssetsAndSync(shares);
    }

    /*//////////////////////////////////////////////////////////////
                     DEPOSIT/WITHDRAWAL LIMIT LOGIC
    //////////////////////////////////////////////////////////////*/

    /**
     * @dev maxDeposit() according the EIP-4626 specification.
     */
    function maxDeposit(address) public view override returns (uint256 maxAssets) {
        if (locked || auctionInProgress || IGuardian(address(lendingPool)).depositPaused()) return 0;

        uint256 supplyCap = lendingPool.supplyCap();
        uint256 realisedLiquidity = lendingPool.totalRealisedLiquidity();
        uint256 interests = lendingPool.calcUnrealisedDebt();

        if (supplyCap > 0) {
            if (realisedLiquidity + interests > supplyCap) return 0;
            maxAssets = supplyCap - realisedLiquidity - interests;
        } else {
            maxAssets = type(uint128).max - realisedLiquidity - interests;
        }
    }

    /**
     * @dev maxMint() according the EIP-4626 specification.
     */
    function maxMint(address) public view override returns (uint256 maxShares) {
        if (locked || auctionInProgress || IGuardian(address(lendingPool)).depositPaused()) return 0;

        uint256 supplyCap = lendingPool.supplyCap();
        uint256 realisedLiquidity = lendingPool.totalRealisedLiquidity();
        uint256 interests = lendingPool.calcUnrealisedDebt();

        if (supplyCap > 0) {
            if (realisedLiquidity + interests > supplyCap) return 0;
            maxShares = convertToShares(supplyCap - realisedLiquidity - interests);
        } else {
            maxShares = convertToShares(type(uint128).max - realisedLiquidity - interests);
        }
    }

    /**
     * @dev maxWithdraw() according the EIP-4626 specification.
     */
    function maxWithdraw(address owner_) public view override returns (uint256 maxAssets) {
        if (locked || auctionInProgress || IGuardian(address(lendingPool)).withdrawPaused()) return 0;

        uint256 availableAssets = asset.balanceOf(address(lendingPool));
        uint256 claimableAssets = convertToAssets(balanceOf[owner_]);

        maxAssets = availableAssets < claimableAssets ? availableAssets : claimableAssets;
    }

    /**
     * @dev maxRedeem() according the EIP-4626 specification.
     */
    function maxRedeem(address owner_) public view override returns (uint256 maxShares) {
        if (locked || auctionInProgress || IGuardian(address(lendingPool)).withdrawPaused()) return 0;

        uint256 claimableShares = balanceOf[owner_];
        if (claimableShares == 0) return 0;
        uint256 availableShares = convertToShares(asset.balanceOf(address(lendingPool)));

        maxShares = availableShares < claimableShares ? availableShares : claimableShares;
    }
}

{
  "compilationTarget": {
    "lib/arcadia-lending/src/Tranche.sol": "Tranche"
  },
  "evmVersion": "london",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": [
    ":arcadia-lending/=lib/arcadia-lending/",
    ":ds-test/=lib/ds-test/src/",
    ":forge-std/=lib/forge-std/src/",
    ":solmate/=lib/solmate/src/",
    ":v2-periphery/=lib/v2-periphery/contracts/"
  ]
}