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Contract Diff Checker

Contract Name:
CreditMessaging

Contract Source Code:

// SPDX-License-Identifier: BSD-2-Clause
pragma solidity ^0.8.4;

/**
* @dev A library for working with mutable byte buffers in Solidity.
*
* Byte buffers are mutable and expandable, and provide a variety of primitives
* for appending to them. At any time you can fetch a bytes object containing the
* current contents of the buffer. The bytes object should not be stored between
* operations, as it may change due to resizing of the buffer.
*/
library Buffer {
    /**
    * @dev Represents a mutable buffer. Buffers have a current value (buf) and
    *      a capacity. The capacity may be longer than the current value, in
    *      which case it can be extended without the need to allocate more memory.
    */
    struct buffer {
        bytes buf;
        uint capacity;
    }

    /**
    * @dev Initializes a buffer with an initial capacity.
    * @param buf The buffer to initialize.
    * @param capacity The number of bytes of space to allocate the buffer.
    * @return The buffer, for chaining.
    */
    function init(buffer memory buf, uint capacity) internal pure returns(buffer memory) {
        if (capacity % 32 != 0) {
            capacity += 32 - (capacity % 32);
        }
        // Allocate space for the buffer data
        buf.capacity = capacity;
        assembly {
            let ptr := mload(0x40)
            mstore(buf, ptr)
            mstore(ptr, 0)
            let fpm := add(32, add(ptr, capacity))
            if lt(fpm, ptr) {
                revert(0, 0)
            }
            mstore(0x40, fpm)
        }
        return buf;
    }

    /**
    * @dev Initializes a new buffer from an existing bytes object.
    *      Changes to the buffer may mutate the original value.
    * @param b The bytes object to initialize the buffer with.
    * @return A new buffer.
    */
    function fromBytes(bytes memory b) internal pure returns(buffer memory) {
        buffer memory buf;
        buf.buf = b;
        buf.capacity = b.length;
        return buf;
    }

    function resize(buffer memory buf, uint capacity) private pure {
        bytes memory oldbuf = buf.buf;
        init(buf, capacity);
        append(buf, oldbuf);
    }

    /**
    * @dev Sets buffer length to 0.
    * @param buf The buffer to truncate.
    * @return The original buffer, for chaining..
    */
    function truncate(buffer memory buf) internal pure returns (buffer memory) {
        assembly {
            let bufptr := mload(buf)
            mstore(bufptr, 0)
        }
        return buf;
    }

    /**
    * @dev Appends len bytes of a byte string to a buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @param len The number of bytes to copy.
    * @return The original buffer, for chaining.
    */
    function append(buffer memory buf, bytes memory data, uint len) internal pure returns(buffer memory) {
        require(len <= data.length);

        uint off = buf.buf.length;
        uint newCapacity = off + len;
        if (newCapacity > buf.capacity) {
            resize(buf, newCapacity * 2);
        }

        uint dest;
        uint src;
        assembly {
            // Memory address of the buffer data
            let bufptr := mload(buf)
            // Length of existing buffer data
            let buflen := mload(bufptr)
            // Start address = buffer address + offset + sizeof(buffer length)
            dest := add(add(bufptr, 32), off)
            // Update buffer length if we're extending it
            if gt(newCapacity, buflen) {
                mstore(bufptr, newCapacity)
            }
            src := add(data, 32)
        }

        // Copy word-length chunks while possible
        for (; len >= 32; len -= 32) {
            assembly {
                mstore(dest, mload(src))
            }
            dest += 32;
            src += 32;
        }

        // Copy remaining bytes
        unchecked {
            uint mask = (256 ** (32 - len)) - 1;
            assembly {
                let srcpart := and(mload(src), not(mask))
                let destpart := and(mload(dest), mask)
                mstore(dest, or(destpart, srcpart))
            }
        }

        return buf;
    }

    /**
    * @dev Appends a byte string to a buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function append(buffer memory buf, bytes memory data) internal pure returns (buffer memory) {
        return append(buf, data, data.length);
    }

    /**
    * @dev Appends a byte to the buffer. Resizes if doing so would exceed the
    *      capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function appendUint8(buffer memory buf, uint8 data) internal pure returns(buffer memory) {
        uint off = buf.buf.length;
        uint offPlusOne = off + 1;
        if (off >= buf.capacity) {
            resize(buf, offPlusOne * 2);
        }

        assembly {
            // Memory address of the buffer data
            let bufptr := mload(buf)
            // Address = buffer address + sizeof(buffer length) + off
            let dest := add(add(bufptr, off), 32)
            mstore8(dest, data)
            // Update buffer length if we extended it
            if gt(offPlusOne, mload(bufptr)) {
                mstore(bufptr, offPlusOne)
            }
        }

        return buf;
    }

    /**
    * @dev Appends len bytes of bytes32 to a buffer. Resizes if doing so would
    *      exceed the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @param len The number of bytes to write (left-aligned).
    * @return The original buffer, for chaining.
    */
    function append(buffer memory buf, bytes32 data, uint len) private pure returns(buffer memory) {
        uint off = buf.buf.length;
        uint newCapacity = len + off;
        if (newCapacity > buf.capacity) {
            resize(buf, newCapacity * 2);
        }

        unchecked {
            uint mask = (256 ** len) - 1;
            // Right-align data
            data = data >> (8 * (32 - len));
            assembly {
                // Memory address of the buffer data
                let bufptr := mload(buf)
                // Address = buffer address + sizeof(buffer length) + newCapacity
                let dest := add(bufptr, newCapacity)
                mstore(dest, or(and(mload(dest), not(mask)), data))
                // Update buffer length if we extended it
                if gt(newCapacity, mload(bufptr)) {
                    mstore(bufptr, newCapacity)
                }
            }
        }
        return buf;
    }

    /**
    * @dev Appends a bytes20 to the buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chhaining.
    */
    function appendBytes20(buffer memory buf, bytes20 data) internal pure returns (buffer memory) {
        return append(buf, bytes32(data), 20);
    }

    /**
    * @dev Appends a bytes32 to the buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function appendBytes32(buffer memory buf, bytes32 data) internal pure returns (buffer memory) {
        return append(buf, data, 32);
    }

    /**
     * @dev Appends a byte to the end of the buffer. Resizes if doing so would
     *      exceed the capacity of the buffer.
     * @param buf The buffer to append to.
     * @param data The data to append.
     * @param len The number of bytes to write (right-aligned).
     * @return The original buffer.
     */
    function appendInt(buffer memory buf, uint data, uint len) internal pure returns(buffer memory) {
        uint off = buf.buf.length;
        uint newCapacity = len + off;
        if (newCapacity > buf.capacity) {
            resize(buf, newCapacity * 2);
        }

        uint mask = (256 ** len) - 1;
        assembly {
            // Memory address of the buffer data
            let bufptr := mload(buf)
            // Address = buffer address + sizeof(buffer length) + newCapacity
            let dest := add(bufptr, newCapacity)
            mstore(dest, or(and(mload(dest), not(mask)), data))
            // Update buffer length if we extended it
            if gt(newCapacity, mload(bufptr)) {
                mstore(bufptr, newCapacity)
            }
        }
        return buf;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

// @dev Import the 'MessagingFee' and 'MessagingReceipt' so it's exposed to OApp implementers
// solhint-disable-next-line no-unused-import
import { OAppSender, MessagingFee, MessagingReceipt } from "./OAppSender.sol";
// @dev Import the 'Origin' so it's exposed to OApp implementers
// solhint-disable-next-line no-unused-import
import { OAppReceiver, Origin } from "./OAppReceiver.sol";
import { OAppCore } from "./OAppCore.sol";

/**
 * @title OApp
 * @dev Abstract contract serving as the base for OApp implementation, combining OAppSender and OAppReceiver functionality.
 */
abstract contract OApp is OAppSender, OAppReceiver {
    /**
     * @dev Constructor to initialize the OApp with the provided endpoint and owner.
     * @param _endpoint The address of the LOCAL LayerZero endpoint.
     * @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
     */
    constructor(address _endpoint, address _delegate) OAppCore(_endpoint, _delegate) {}

    /**
     * @notice Retrieves the OApp version information.
     * @return senderVersion The version of the OAppSender.sol implementation.
     * @return receiverVersion The version of the OAppReceiver.sol implementation.
     */
    function oAppVersion()
        public
        pure
        virtual
        override(OAppSender, OAppReceiver)
        returns (uint64 senderVersion, uint64 receiverVersion)
    {
        return (SENDER_VERSION, RECEIVER_VERSION);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
import { IOAppCore, ILayerZeroEndpointV2 } from "./interfaces/IOAppCore.sol";

/**
 * @title OAppCore
 * @dev Abstract contract implementing the IOAppCore interface with basic OApp configurations.
 */
abstract contract OAppCore is IOAppCore, Ownable {
    // The LayerZero endpoint associated with the given OApp
    ILayerZeroEndpointV2 public immutable endpoint;

    // Mapping to store peers associated with corresponding endpoints
    mapping(uint32 eid => bytes32 peer) public peers;

    /**
     * @dev Constructor to initialize the OAppCore with the provided endpoint and delegate.
     * @param _endpoint The address of the LOCAL Layer Zero endpoint.
     * @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
     *
     * @dev The delegate typically should be set as the owner of the contract.
     */
    constructor(address _endpoint, address _delegate) {
        endpoint = ILayerZeroEndpointV2(_endpoint);

        if (_delegate == address(0)) revert InvalidDelegate();
        endpoint.setDelegate(_delegate);
    }

    /**
     * @notice Sets the peer address (OApp instance) for a corresponding endpoint.
     * @param _eid The endpoint ID.
     * @param _peer The address of the peer to be associated with the corresponding endpoint.
     *
     * @dev Only the owner/admin of the OApp can call this function.
     * @dev Indicates that the peer is trusted to send LayerZero messages to this OApp.
     * @dev Set this to bytes32(0) to remove the peer address.
     * @dev Peer is a bytes32 to accommodate non-evm chains.
     */
    function setPeer(uint32 _eid, bytes32 _peer) public virtual onlyOwner {
        _setPeer(_eid, _peer);
    }

    /**
     * @notice Sets the peer address (OApp instance) for a corresponding endpoint.
     * @param _eid The endpoint ID.
     * @param _peer The address of the peer to be associated with the corresponding endpoint.
     *
     * @dev Indicates that the peer is trusted to send LayerZero messages to this OApp.
     * @dev Set this to bytes32(0) to remove the peer address.
     * @dev Peer is a bytes32 to accommodate non-evm chains.
     */
    function _setPeer(uint32 _eid, bytes32 _peer) internal virtual {
        peers[_eid] = _peer;
        emit PeerSet(_eid, _peer);
    }

    /**
     * @notice Internal function to get the peer address associated with a specific endpoint; reverts if NOT set.
     * ie. the peer is set to bytes32(0).
     * @param _eid The endpoint ID.
     * @return peer The address of the peer associated with the specified endpoint.
     */
    function _getPeerOrRevert(uint32 _eid) internal view virtual returns (bytes32) {
        bytes32 peer = peers[_eid];
        if (peer == bytes32(0)) revert NoPeer(_eid);
        return peer;
    }

    /**
     * @notice Sets the delegate address for the OApp.
     * @param _delegate The address of the delegate to be set.
     *
     * @dev Only the owner/admin of the OApp can call this function.
     * @dev Provides the ability for a delegate to set configs, on behalf of the OApp, directly on the Endpoint contract.
     */
    function setDelegate(address _delegate) public onlyOwner {
        endpoint.setDelegate(_delegate);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { IOAppReceiver, Origin } from "./interfaces/IOAppReceiver.sol";
import { OAppCore } from "./OAppCore.sol";

/**
 * @title OAppReceiver
 * @dev Abstract contract implementing the ILayerZeroReceiver interface and extending OAppCore for OApp receivers.
 */
abstract contract OAppReceiver is IOAppReceiver, OAppCore {
    // Custom error message for when the caller is not the registered endpoint/
    error OnlyEndpoint(address addr);

    // @dev The version of the OAppReceiver implementation.
    // @dev Version is bumped when changes are made to this contract.
    uint64 internal constant RECEIVER_VERSION = 2;

    /**
     * @notice Retrieves the OApp version information.
     * @return senderVersion The version of the OAppSender.sol contract.
     * @return receiverVersion The version of the OAppReceiver.sol contract.
     *
     * @dev Providing 0 as the default for OAppSender version. Indicates that the OAppSender is not implemented.
     * ie. this is a RECEIVE only OApp.
     * @dev If the OApp uses both OAppSender and OAppReceiver, then this needs to be override returning the correct versions.
     */
    function oAppVersion() public view virtual returns (uint64 senderVersion, uint64 receiverVersion) {
        return (0, RECEIVER_VERSION);
    }

    /**
     * @notice Indicates whether an address is an approved composeMsg sender to the Endpoint.
     * @dev _origin The origin information containing the source endpoint and sender address.
     *  - srcEid: The source chain endpoint ID.
     *  - sender: The sender address on the src chain.
     *  - nonce: The nonce of the message.
     * @dev _message The lzReceive payload.
     * @param _sender The sender address.
     * @return isSender Is a valid sender.
     *
     * @dev Applications can optionally choose to implement separate composeMsg senders that are NOT the bridging layer.
     * @dev The default sender IS the OAppReceiver implementer.
     */
    function isComposeMsgSender(
        Origin calldata /*_origin*/,
        bytes calldata /*_message*/,
        address _sender
    ) public view virtual returns (bool) {
        return _sender == address(this);
    }

    /**
     * @notice Checks if the path initialization is allowed based on the provided origin.
     * @param origin The origin information containing the source endpoint and sender address.
     * @return Whether the path has been initialized.
     *
     * @dev This indicates to the endpoint that the OApp has enabled msgs for this particular path to be received.
     * @dev This defaults to assuming if a peer has been set, its initialized.
     * Can be overridden by the OApp if there is other logic to determine this.
     */
    function allowInitializePath(Origin calldata origin) public view virtual returns (bool) {
        return peers[origin.srcEid] == origin.sender;
    }

    /**
     * @notice Retrieves the next nonce for a given source endpoint and sender address.
     * @dev _srcEid The source endpoint ID.
     * @dev _sender The sender address.
     * @return nonce The next nonce.
     *
     * @dev The path nonce starts from 1. If 0 is returned it means that there is NO nonce ordered enforcement.
     * @dev Is required by the off-chain executor to determine the OApp expects msg execution is ordered.
     * @dev This is also enforced by the OApp.
     * @dev By default this is NOT enabled. ie. nextNonce is hardcoded to return 0.
     */
    function nextNonce(uint32 /*_srcEid*/, bytes32 /*_sender*/) public view virtual returns (uint64 nonce) {
        return 0;
    }

    /**
     * @dev Entry point for receiving messages or packets from the endpoint.
     * @param _origin The origin information containing the source endpoint and sender address.
     *  - srcEid: The source chain endpoint ID.
     *  - sender: The sender address on the src chain.
     *  - nonce: The nonce of the message.
     * @param _guid The unique identifier for the received LayerZero message.
     * @param _message The payload of the received message.
     * @param _executor The address of the executor for the received message.
     * @param _extraData Additional arbitrary data provided by the corresponding executor.
     *
     * @dev Entry point for receiving msg/packet from the LayerZero endpoint.
     */
    function lzReceive(
        Origin calldata _origin,
        bytes32 _guid,
        bytes calldata _message,
        address _executor,
        bytes calldata _extraData
    ) public payable virtual {
        // Ensures that only the endpoint can attempt to lzReceive() messages to this OApp.
        if (address(endpoint) != msg.sender) revert OnlyEndpoint(msg.sender);

        // Ensure that the sender matches the expected peer for the source endpoint.
        if (_getPeerOrRevert(_origin.srcEid) != _origin.sender) revert OnlyPeer(_origin.srcEid, _origin.sender);

        // Call the internal OApp implementation of lzReceive.
        _lzReceive(_origin, _guid, _message, _executor, _extraData);
    }

    /**
     * @dev Internal function to implement lzReceive logic without needing to copy the basic parameter validation.
     */
    function _lzReceive(
        Origin calldata _origin,
        bytes32 _guid,
        bytes calldata _message,
        address _executor,
        bytes calldata _extraData
    ) internal virtual;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { SafeERC20, IERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { MessagingParams, MessagingFee, MessagingReceipt } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";
import { OAppCore } from "./OAppCore.sol";

/**
 * @title OAppSender
 * @dev Abstract contract implementing the OAppSender functionality for sending messages to a LayerZero endpoint.
 */
abstract contract OAppSender is OAppCore {
    using SafeERC20 for IERC20;

    // Custom error messages
    error NotEnoughNative(uint256 msgValue);
    error LzTokenUnavailable();

    // @dev The version of the OAppSender implementation.
    // @dev Version is bumped when changes are made to this contract.
    uint64 internal constant SENDER_VERSION = 1;

    /**
     * @notice Retrieves the OApp version information.
     * @return senderVersion The version of the OAppSender.sol contract.
     * @return receiverVersion The version of the OAppReceiver.sol contract.
     *
     * @dev Providing 0 as the default for OAppReceiver version. Indicates that the OAppReceiver is not implemented.
     * ie. this is a SEND only OApp.
     * @dev If the OApp uses both OAppSender and OAppReceiver, then this needs to be override returning the correct versions
     */
    function oAppVersion() public view virtual returns (uint64 senderVersion, uint64 receiverVersion) {
        return (SENDER_VERSION, 0);
    }

    /**
     * @dev Internal function to interact with the LayerZero EndpointV2.quote() for fee calculation.
     * @param _dstEid The destination endpoint ID.
     * @param _message The message payload.
     * @param _options Additional options for the message.
     * @param _payInLzToken Flag indicating whether to pay the fee in LZ tokens.
     * @return fee The calculated MessagingFee for the message.
     *      - nativeFee: The native fee for the message.
     *      - lzTokenFee: The LZ token fee for the message.
     */
    function _quote(
        uint32 _dstEid,
        bytes memory _message,
        bytes memory _options,
        bool _payInLzToken
    ) internal view virtual returns (MessagingFee memory fee) {
        return
            endpoint.quote(
                MessagingParams(_dstEid, _getPeerOrRevert(_dstEid), _message, _options, _payInLzToken),
                address(this)
            );
    }

    /**
     * @dev Internal function to interact with the LayerZero EndpointV2.send() for sending a message.
     * @param _dstEid The destination endpoint ID.
     * @param _message The message payload.
     * @param _options Additional options for the message.
     * @param _fee The calculated LayerZero fee for the message.
     *      - nativeFee: The native fee.
     *      - lzTokenFee: The lzToken fee.
     * @param _refundAddress The address to receive any excess fee values sent to the endpoint.
     * @return receipt The receipt for the sent message.
     *      - guid: The unique identifier for the sent message.
     *      - nonce: The nonce of the sent message.
     *      - fee: The LayerZero fee incurred for the message.
     */
    function _lzSend(
        uint32 _dstEid,
        bytes memory _message,
        bytes memory _options,
        MessagingFee memory _fee,
        address _refundAddress
    ) internal virtual returns (MessagingReceipt memory receipt) {
        // @dev Push corresponding fees to the endpoint, any excess is sent back to the _refundAddress from the endpoint.
        uint256 messageValue = _payNative(_fee.nativeFee);
        if (_fee.lzTokenFee > 0) _payLzToken(_fee.lzTokenFee);

        return
            // solhint-disable-next-line check-send-result
            endpoint.send{ value: messageValue }(
                MessagingParams(_dstEid, _getPeerOrRevert(_dstEid), _message, _options, _fee.lzTokenFee > 0),
                _refundAddress
            );
    }

    /**
     * @dev Internal function to pay the native fee associated with the message.
     * @param _nativeFee The native fee to be paid.
     * @return nativeFee The amount of native currency paid.
     *
     * @dev If the OApp needs to initiate MULTIPLE LayerZero messages in a single transaction,
     * this will need to be overridden because msg.value would contain multiple lzFees.
     * @dev Should be overridden in the event the LayerZero endpoint requires a different native currency.
     * @dev Some EVMs use an ERC20 as a method for paying transactions/gasFees.
     * @dev The endpoint is EITHER/OR, ie. it will NOT support both types of native payment at a time.
     */
    function _payNative(uint256 _nativeFee) internal virtual returns (uint256 nativeFee) {
        if (msg.value != _nativeFee) revert NotEnoughNative(msg.value);
        return _nativeFee;
    }

    /**
     * @dev Internal function to pay the LZ token fee associated with the message.
     * @param _lzTokenFee The LZ token fee to be paid.
     *
     * @dev If the caller is trying to pay in the specified lzToken, then the lzTokenFee is passed to the endpoint.
     * @dev Any excess sent, is passed back to the specified _refundAddress in the _lzSend().
     */
    function _payLzToken(uint256 _lzTokenFee) internal virtual {
        // @dev Cannot cache the token because it is not immutable in the endpoint.
        address lzToken = endpoint.lzToken();
        if (lzToken == address(0)) revert LzTokenUnavailable();

        // Pay LZ token fee by sending tokens to the endpoint.
        IERC20(lzToken).safeTransferFrom(msg.sender, address(endpoint), _lzTokenFee);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { ILayerZeroEndpointV2 } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";

/**
 * @title IOAppCore
 */
interface IOAppCore {
    // Custom error messages
    error OnlyPeer(uint32 eid, bytes32 sender);
    error NoPeer(uint32 eid);
    error InvalidEndpointCall();
    error InvalidDelegate();

    // Event emitted when a peer (OApp) is set for a corresponding endpoint
    event PeerSet(uint32 eid, bytes32 peer);

    /**
     * @notice Retrieves the OApp version information.
     * @return senderVersion The version of the OAppSender.sol contract.
     * @return receiverVersion The version of the OAppReceiver.sol contract.
     */
    function oAppVersion() external view returns (uint64 senderVersion, uint64 receiverVersion);

    /**
     * @notice Retrieves the LayerZero endpoint associated with the OApp.
     * @return iEndpoint The LayerZero endpoint as an interface.
     */
    function endpoint() external view returns (ILayerZeroEndpointV2 iEndpoint);

    /**
     * @notice Retrieves the peer (OApp) associated with a corresponding endpoint.
     * @param _eid The endpoint ID.
     * @return peer The peer address (OApp instance) associated with the corresponding endpoint.
     */
    function peers(uint32 _eid) external view returns (bytes32 peer);

    /**
     * @notice Sets the peer address (OApp instance) for a corresponding endpoint.
     * @param _eid The endpoint ID.
     * @param _peer The address of the peer to be associated with the corresponding endpoint.
     */
    function setPeer(uint32 _eid, bytes32 _peer) external;

    /**
     * @notice Sets the delegate address for the OApp Core.
     * @param _delegate The address of the delegate to be set.
     */
    function setDelegate(address _delegate) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

/**
 * @dev Struct representing enforced option parameters.
 */
struct EnforcedOptionParam {
    uint32 eid; // Endpoint ID
    uint16 msgType; // Message Type
    bytes options; // Additional options
}

/**
 * @title IOAppOptionsType3
 * @dev Interface for the OApp with Type 3 Options, allowing the setting and combining of enforced options.
 */
interface IOAppOptionsType3 {
    // Custom error message for invalid options
    error InvalidOptions(bytes options);

    // Event emitted when enforced options are set
    event EnforcedOptionSet(EnforcedOptionParam[] _enforcedOptions);

    /**
     * @notice Sets enforced options for specific endpoint and message type combinations.
     * @param _enforcedOptions An array of EnforcedOptionParam structures specifying enforced options.
     */
    function setEnforcedOptions(EnforcedOptionParam[] calldata _enforcedOptions) external;

    /**
     * @notice Combines options for a given endpoint and message type.
     * @param _eid The endpoint ID.
     * @param _msgType The OApp message type.
     * @param _extraOptions Additional options passed by the caller.
     * @return options The combination of caller specified options AND enforced options.
     */
    function combineOptions(
        uint32 _eid,
        uint16 _msgType,
        bytes calldata _extraOptions
    ) external view returns (bytes memory options);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

import { ILayerZeroReceiver, Origin } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroReceiver.sol";

interface IOAppReceiver is ILayerZeroReceiver {
    /**
     * @notice Indicates whether an address is an approved composeMsg sender to the Endpoint.
     * @param _origin The origin information containing the source endpoint and sender address.
     *  - srcEid: The source chain endpoint ID.
     *  - sender: The sender address on the src chain.
     *  - nonce: The nonce of the message.
     * @param _message The lzReceive payload.
     * @param _sender The sender address.
     * @return isSender Is a valid sender.
     *
     * @dev Applications can optionally choose to implement a separate composeMsg sender that is NOT the bridging layer.
     * @dev The default sender IS the OAppReceiver implementer.
     */
    function isComposeMsgSender(
        Origin calldata _origin,
        bytes calldata _message,
        address _sender
    ) external view returns (bool isSender);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
import { IOAppOptionsType3, EnforcedOptionParam } from "../interfaces/IOAppOptionsType3.sol";

/**
 * @title OAppOptionsType3
 * @dev Abstract contract implementing the IOAppOptionsType3 interface with type 3 options.
 */
abstract contract OAppOptionsType3 is IOAppOptionsType3, Ownable {
    uint16 internal constant OPTION_TYPE_3 = 3;

    // @dev The "msgType" should be defined in the child contract.
    mapping(uint32 eid => mapping(uint16 msgType => bytes enforcedOption)) public enforcedOptions;

    /**
     * @dev Sets the enforced options for specific endpoint and message type combinations.
     * @param _enforcedOptions An array of EnforcedOptionParam structures specifying enforced options.
     *
     * @dev Only the owner/admin of the OApp can call this function.
     * @dev Provides a way for the OApp to enforce things like paying for PreCrime, AND/OR minimum dst lzReceive gas amounts etc.
     * @dev These enforced options can vary as the potential options/execution on the remote may differ as per the msgType.
     * eg. Amount of lzReceive() gas necessary to deliver a lzCompose() message adds overhead you dont want to pay
     * if you are only making a standard LayerZero message ie. lzReceive() WITHOUT sendCompose().
     */
    function setEnforcedOptions(EnforcedOptionParam[] calldata _enforcedOptions) public virtual onlyOwner {
        _setEnforcedOptions(_enforcedOptions);
    }

    /**
     * @dev Sets the enforced options for specific endpoint and message type combinations.
     * @param _enforcedOptions An array of EnforcedOptionParam structures specifying enforced options.
     *
     * @dev Provides a way for the OApp to enforce things like paying for PreCrime, AND/OR minimum dst lzReceive gas amounts etc.
     * @dev These enforced options can vary as the potential options/execution on the remote may differ as per the msgType.
     * eg. Amount of lzReceive() gas necessary to deliver a lzCompose() message adds overhead you dont want to pay
     * if you are only making a standard LayerZero message ie. lzReceive() WITHOUT sendCompose().
     */
    function _setEnforcedOptions(EnforcedOptionParam[] memory _enforcedOptions) internal virtual {
        for (uint256 i = 0; i < _enforcedOptions.length; i++) {
            // @dev Enforced options are only available for optionType 3, as type 1 and 2 dont support combining.
            _assertOptionsType3(_enforcedOptions[i].options);
            enforcedOptions[_enforcedOptions[i].eid][_enforcedOptions[i].msgType] = _enforcedOptions[i].options;
        }

        emit EnforcedOptionSet(_enforcedOptions);
    }

    /**
     * @notice Combines options for a given endpoint and message type.
     * @param _eid The endpoint ID.
     * @param _msgType The OAPP message type.
     * @param _extraOptions Additional options passed by the caller.
     * @return options The combination of caller specified options AND enforced options.
     *
     * @dev If there is an enforced lzReceive option:
     * - {gasLimit: 200k, msg.value: 1 ether} AND a caller supplies a lzReceive option: {gasLimit: 100k, msg.value: 0.5 ether}
     * - The resulting options will be {gasLimit: 300k, msg.value: 1.5 ether} when the message is executed on the remote lzReceive() function.
     * @dev This presence of duplicated options is handled off-chain in the verifier/executor.
     */
    function combineOptions(
        uint32 _eid,
        uint16 _msgType,
        bytes calldata _extraOptions
    ) public view virtual returns (bytes memory) {
        bytes memory enforced = enforcedOptions[_eid][_msgType];

        // No enforced options, pass whatever the caller supplied, even if it's empty or legacy type 1/2 options.
        if (enforced.length == 0) return _extraOptions;

        // No caller options, return enforced
        if (_extraOptions.length == 0) return enforced;

        // @dev If caller provided _extraOptions, must be type 3 as its the ONLY type that can be combined.
        if (_extraOptions.length >= 2) {
            _assertOptionsType3(_extraOptions);
            // @dev Remove the first 2 bytes containing the type from the _extraOptions and combine with enforced.
            return bytes.concat(enforced, _extraOptions[2:]);
        }

        // No valid set of options was found.
        revert InvalidOptions(_extraOptions);
    }

    /**
     * @dev Internal function to assert that options are of type 3.
     * @param _options The options to be checked.
     */
    function _assertOptionsType3(bytes memory _options) internal pure virtual {
        uint16 optionsType;
        assembly {
            optionsType := mload(add(_options, 2))
        }
        if (optionsType != OPTION_TYPE_3) revert InvalidOptions(_options);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { MessagingReceipt, MessagingFee } from "../../oapp/OAppSender.sol";

/**
 * @dev Struct representing token parameters for the OFT send() operation.
 */
struct SendParam {
    uint32 dstEid; // Destination endpoint ID.
    bytes32 to; // Recipient address.
    uint256 amountLD; // Amount to send in local decimals.
    uint256 minAmountLD; // Minimum amount to send in local decimals.
    bytes extraOptions; // Additional options supplied by the caller to be used in the LayerZero message.
    bytes composeMsg; // The composed message for the send() operation.
    bytes oftCmd; // The OFT command to be executed, unused in default OFT implementations.
}

/**
 * @dev Struct representing OFT limit information.
 * @dev These amounts can change dynamically and are up the the specific oft implementation.
 */
struct OFTLimit {
    uint256 minAmountLD; // Minimum amount in local decimals that can be sent to the recipient.
    uint256 maxAmountLD; // Maximum amount in local decimals that can be sent to the recipient.
}

/**
 * @dev Struct representing OFT receipt information.
 */
struct OFTReceipt {
    uint256 amountSentLD; // Amount of tokens ACTUALLY debited from the sender in local decimals.
    // @dev In non-default implementations, the amountReceivedLD COULD differ from this value.
    uint256 amountReceivedLD; // Amount of tokens to be received on the remote side.
}

/**
 * @dev Struct representing OFT fee details.
 * @dev Future proof mechanism to provide a standardized way to communicate fees to things like a UI.
 */
struct OFTFeeDetail {
    int256 feeAmountLD; // Amount of the fee in local decimals.
    string description; // Description of the fee.
}

/**
 * @title IOFT
 * @dev Interface for the OftChain (OFT) token.
 * @dev Does not inherit ERC20 to accommodate usage by OFTAdapter as well.
 * @dev This specific interface ID is '0x02e49c2c'.
 */
interface IOFT {
    // Custom error messages
    error InvalidLocalDecimals();
    error SlippageExceeded(uint256 amountLD, uint256 minAmountLD);

    // Events
    event OFTSent(
        bytes32 indexed guid, // GUID of the OFT message.
        uint32 dstEid, // Destination Endpoint ID.
        address indexed fromAddress, // Address of the sender on the src chain.
        uint256 amountSentLD, // Amount of tokens sent in local decimals.
        uint256 amountReceivedLD // Amount of tokens received in local decimals.
    );
    event OFTReceived(
        bytes32 indexed guid, // GUID of the OFT message.
        uint32 srcEid, // Source Endpoint ID.
        address indexed toAddress, // Address of the recipient on the dst chain.
        uint256 amountReceivedLD // Amount of tokens received in local decimals.
    );

    /**
     * @notice Retrieves interfaceID and the version of the OFT.
     * @return interfaceId The interface ID.
     * @return version The version.
     *
     * @dev interfaceId: This specific interface ID is '0x02e49c2c'.
     * @dev version: Indicates a cross-chain compatible msg encoding with other OFTs.
     * @dev If a new feature is added to the OFT cross-chain msg encoding, the version will be incremented.
     * ie. localOFT version(x,1) CAN send messages to remoteOFT version(x,1)
     */
    function oftVersion() external view returns (bytes4 interfaceId, uint64 version);

    /**
     * @notice Retrieves the address of the token associated with the OFT.
     * @return token The address of the ERC20 token implementation.
     */
    function token() external view returns (address);

    /**
     * @notice Indicates whether the OFT contract requires approval of the 'token()' to send.
     * @return requiresApproval Needs approval of the underlying token implementation.
     *
     * @dev Allows things like wallet implementers to determine integration requirements,
     * without understanding the underlying token implementation.
     */
    function approvalRequired() external view returns (bool);

    /**
     * @notice Retrieves the shared decimals of the OFT.
     * @return sharedDecimals The shared decimals of the OFT.
     */
    function sharedDecimals() external view returns (uint8);

    /**
     * @notice Provides a quote for OFT-related operations.
     * @param _sendParam The parameters for the send operation.
     * @return limit The OFT limit information.
     * @return oftFeeDetails The details of OFT fees.
     * @return receipt The OFT receipt information.
     */
    function quoteOFT(
        SendParam calldata _sendParam
    ) external view returns (OFTLimit memory, OFTFeeDetail[] memory oftFeeDetails, OFTReceipt memory);

    /**
     * @notice Provides a quote for the send() operation.
     * @param _sendParam The parameters for the send() operation.
     * @param _payInLzToken Flag indicating whether the caller is paying in the LZ token.
     * @return fee The calculated LayerZero messaging fee from the send() operation.
     *
     * @dev MessagingFee: LayerZero msg fee
     *  - nativeFee: The native fee.
     *  - lzTokenFee: The lzToken fee.
     */
    function quoteSend(SendParam calldata _sendParam, bool _payInLzToken) external view returns (MessagingFee memory);

    /**
     * @notice Executes the send() operation.
     * @param _sendParam The parameters for the send operation.
     * @param _fee The fee information supplied by the caller.
     *      - nativeFee: The native fee.
     *      - lzTokenFee: The lzToken fee.
     * @param _refundAddress The address to receive any excess funds from fees etc. on the src.
     * @return receipt The LayerZero messaging receipt from the send() operation.
     * @return oftReceipt The OFT receipt information.
     *
     * @dev MessagingReceipt: LayerZero msg receipt
     *  - guid: The unique identifier for the sent message.
     *  - nonce: The nonce of the sent message.
     *  - fee: The LayerZero fee incurred for the message.
     */
    function send(
        SendParam calldata _sendParam,
        MessagingFee calldata _fee,
        address _refundAddress
    ) external payable returns (MessagingReceipt memory, OFTReceipt memory);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
import { IPreCrime } from "./interfaces/IPreCrime.sol";
import { IOAppPreCrimeSimulator, InboundPacket, Origin } from "./interfaces/IOAppPreCrimeSimulator.sol";

/**
 * @title OAppPreCrimeSimulator
 * @dev Abstract contract serving as the base for preCrime simulation functionality in an OApp.
 */
abstract contract OAppPreCrimeSimulator is IOAppPreCrimeSimulator, Ownable {
    // The address of the preCrime implementation.
    address public preCrime;

    /**
     * @dev Retrieves the address of the OApp contract.
     * @return The address of the OApp contract.
     *
     * @dev The simulator contract is the base contract for the OApp by default.
     * @dev If the simulator is a separate contract, override this function.
     */
    function oApp() external view virtual returns (address) {
        return address(this);
    }

    /**
     * @dev Sets the preCrime contract address.
     * @param _preCrime The address of the preCrime contract.
     */
    function setPreCrime(address _preCrime) public virtual onlyOwner {
        preCrime = _preCrime;
        emit PreCrimeSet(_preCrime);
    }

    /**
     * @dev Interface for pre-crime simulations. Always reverts at the end with the simulation results.
     * @param _packets An array of InboundPacket objects representing received packets to be delivered.
     *
     * @dev WARNING: MUST revert at the end with the simulation results.
     * @dev Gives the preCrime implementation the ability to mock sending packets to the lzReceive function,
     * WITHOUT actually executing them.
     */
    function lzReceiveAndRevert(InboundPacket[] calldata _packets) public payable virtual {
        for (uint256 i = 0; i < _packets.length; i++) {
            InboundPacket calldata packet = _packets[i];

            // Ignore packets that are not from trusted peers.
            if (!isPeer(packet.origin.srcEid, packet.origin.sender)) continue;

            // @dev Because a verifier is calling this function, it doesnt have access to executor params:
            //  - address _executor
            //  - bytes calldata _extraData
            // preCrime will NOT work for OApps that rely on these two parameters inside of their _lzReceive().
            // They are instead stubbed to default values, address(0) and bytes("")
            // @dev Calling this.lzReceiveSimulate removes ability for assembly return 0 callstack exit,
            // which would cause the revert to be ignored.
            this.lzReceiveSimulate{ value: packet.value }(
                packet.origin,
                packet.guid,
                packet.message,
                packet.executor,
                packet.extraData
            );
        }

        // @dev Revert with the simulation results. msg.sender must implement IPreCrime.buildSimulationResult().
        revert SimulationResult(IPreCrime(msg.sender).buildSimulationResult());
    }

    /**
     * @dev Is effectively an internal function because msg.sender must be address(this).
     * Allows resetting the call stack for 'internal' calls.
     * @param _origin The origin information containing the source endpoint and sender address.
     *  - srcEid: The source chain endpoint ID.
     *  - sender: The sender address on the src chain.
     *  - nonce: The nonce of the message.
     * @param _guid The unique identifier of the packet.
     * @param _message The message payload of the packet.
     * @param _executor The executor address for the packet.
     * @param _extraData Additional data for the packet.
     */
    function lzReceiveSimulate(
        Origin calldata _origin,
        bytes32 _guid,
        bytes calldata _message,
        address _executor,
        bytes calldata _extraData
    ) external payable virtual {
        // @dev Ensure ONLY can be called 'internally'.
        if (msg.sender != address(this)) revert OnlySelf();
        _lzReceiveSimulate(_origin, _guid, _message, _executor, _extraData);
    }

    /**
     * @dev Internal function to handle the OAppPreCrimeSimulator simulated receive.
     * @param _origin The origin information.
     *  - srcEid: The source chain endpoint ID.
     *  - sender: The sender address from the src chain.
     *  - nonce: The nonce of the LayerZero message.
     * @param _guid The GUID of the LayerZero message.
     * @param _message The LayerZero message.
     * @param _executor The address of the off-chain executor.
     * @param _extraData Arbitrary data passed by the msg executor.
     *
     * @dev Enables the preCrime simulator to mock sending lzReceive() messages,
     * routes the msg down from the OAppPreCrimeSimulator, and back up to the OAppReceiver.
     */
    function _lzReceiveSimulate(
        Origin calldata _origin,
        bytes32 _guid,
        bytes calldata _message,
        address _executor,
        bytes calldata _extraData
    ) internal virtual;

    /**
     * @dev checks if the specified peer is considered 'trusted' by the OApp.
     * @param _eid The endpoint Id to check.
     * @param _peer The peer to check.
     * @return Whether the peer passed is considered 'trusted' by the OApp.
     */
    function isPeer(uint32 _eid, bytes32 _peer) public view virtual returns (bool);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

// @dev Import the Origin so it's exposed to OAppPreCrimeSimulator implementers.
// solhint-disable-next-line no-unused-import
import { InboundPacket, Origin } from "../libs/Packet.sol";

/**
 * @title IOAppPreCrimeSimulator Interface
 * @dev Interface for the preCrime simulation functionality in an OApp.
 */
interface IOAppPreCrimeSimulator {
    // @dev simulation result used in PreCrime implementation
    error SimulationResult(bytes result);
    error OnlySelf();

    /**
     * @dev Emitted when the preCrime contract address is set.
     * @param preCrimeAddress The address of the preCrime contract.
     */
    event PreCrimeSet(address preCrimeAddress);

    /**
     * @dev Retrieves the address of the preCrime contract implementation.
     * @return The address of the preCrime contract.
     */
    function preCrime() external view returns (address);

    /**
     * @dev Retrieves the address of the OApp contract.
     * @return The address of the OApp contract.
     */
    function oApp() external view returns (address);

    /**
     * @dev Sets the preCrime contract address.
     * @param _preCrime The address of the preCrime contract.
     */
    function setPreCrime(address _preCrime) external;

    /**
     * @dev Mocks receiving a packet, then reverts with a series of data to infer the state/result.
     * @param _packets An array of LayerZero InboundPacket objects representing received packets.
     */
    function lzReceiveAndRevert(InboundPacket[] calldata _packets) external payable;

    /**
     * @dev checks if the specified peer is considered 'trusted' by the OApp.
     * @param _eid The endpoint Id to check.
     * @param _peer The peer to check.
     * @return Whether the peer passed is considered 'trusted' by the OApp.
     */
    function isPeer(uint32 _eid, bytes32 _peer) external view returns (bool);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;
struct PreCrimePeer {
    uint32 eid;
    bytes32 preCrime;
    bytes32 oApp;
}

// TODO not done yet
interface IPreCrime {
    error OnlyOffChain();

    // for simulate()
    error PacketOversize(uint256 max, uint256 actual);
    error PacketUnsorted();
    error SimulationFailed(bytes reason);

    // for preCrime()
    error SimulationResultNotFound(uint32 eid);
    error InvalidSimulationResult(uint32 eid, bytes reason);
    error CrimeFound(bytes crime);

    function getConfig(bytes[] calldata _packets, uint256[] calldata _packetMsgValues) external returns (bytes memory);

    function simulate(
        bytes[] calldata _packets,
        uint256[] calldata _packetMsgValues
    ) external payable returns (bytes memory);

    function buildSimulationResult() external view returns (bytes memory);

    function preCrime(
        bytes[] calldata _packets,
        uint256[] calldata _packetMsgValues,
        bytes[] calldata _simulations
    ) external;

    function version() external view returns (uint64 major, uint8 minor);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.20;

import { Origin } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";
import { PacketV1Codec } from "@layerzerolabs/lz-evm-protocol-v2/contracts/messagelib/libs/PacketV1Codec.sol";

/**
 * @title InboundPacket
 * @dev Structure representing an inbound packet received by the contract.
 */
struct InboundPacket {
    Origin origin; // Origin information of the packet.
    uint32 dstEid; // Destination endpointId of the packet.
    address receiver; // Receiver address for the packet.
    bytes32 guid; // Unique identifier of the packet.
    uint256 value; // msg.value of the packet.
    address executor; // Executor address for the packet.
    bytes message; // Message payload of the packet.
    bytes extraData; // Additional arbitrary data for the packet.
}

/**
 * @title PacketDecoder
 * @dev Library for decoding LayerZero packets.
 */
library PacketDecoder {
    using PacketV1Codec for bytes;

    /**
     * @dev Decode an inbound packet from the given packet data.
     * @param _packet The packet data to decode.
     * @return packet An InboundPacket struct representing the decoded packet.
     */
    function decode(bytes calldata _packet) internal pure returns (InboundPacket memory packet) {
        packet.origin = Origin(_packet.srcEid(), _packet.sender(), _packet.nonce());
        packet.dstEid = _packet.dstEid();
        packet.receiver = _packet.receiverB20();
        packet.guid = _packet.guid();
        packet.message = _packet.message();
    }

    /**
     * @dev Decode multiple inbound packets from the given packet data and associated message values.
     * @param _packets An array of packet data to decode.
     * @param _packetMsgValues An array of associated message values for each packet.
     * @return packets An array of InboundPacket structs representing the decoded packets.
     */
    function decode(
        bytes[] calldata _packets,
        uint256[] memory _packetMsgValues
    ) internal pure returns (InboundPacket[] memory packets) {
        packets = new InboundPacket[](_packets.length);
        for (uint256 i = 0; i < _packets.length; i++) {
            bytes calldata packet = _packets[i];
            packets[i] = PacketDecoder.decode(packet);
            // @dev Allows the verifier to specify the msg.value that gets passed in lzReceive.
            packets[i].value = _packetMsgValues[i];
        }
    }
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

import { IMessageLibManager } from "./IMessageLibManager.sol";
import { IMessagingComposer } from "./IMessagingComposer.sol";
import { IMessagingChannel } from "./IMessagingChannel.sol";
import { IMessagingContext } from "./IMessagingContext.sol";

struct MessagingParams {
    uint32 dstEid;
    bytes32 receiver;
    bytes message;
    bytes options;
    bool payInLzToken;
}

struct MessagingReceipt {
    bytes32 guid;
    uint64 nonce;
    MessagingFee fee;
}

struct MessagingFee {
    uint256 nativeFee;
    uint256 lzTokenFee;
}

struct Origin {
    uint32 srcEid;
    bytes32 sender;
    uint64 nonce;
}

enum ExecutionState {
    NotExecutable,
    Executable,
    Executed
}

interface ILayerZeroEndpointV2 is IMessageLibManager, IMessagingComposer, IMessagingChannel, IMessagingContext {
    event PacketSent(bytes encodedPayload, bytes options, address sendLibrary);

    event PacketVerified(Origin origin, address receiver, bytes32 payloadHash);

    event PacketDelivered(Origin origin, address receiver);

    event LzReceiveAlert(
        address indexed receiver,
        address indexed executor,
        Origin origin,
        bytes32 guid,
        uint256 gas,
        uint256 value,
        bytes message,
        bytes extraData,
        bytes reason
    );

    event LzTokenSet(address token);

    function quote(MessagingParams calldata _params, address _sender) external view returns (MessagingFee memory);

    function send(
        MessagingParams calldata _params,
        address _refundAddress
    ) external payable returns (MessagingReceipt memory);

    function verify(Origin calldata _origin, address _receiver, bytes32 _payloadHash) external;

    function verifiable(
        Origin calldata _origin,
        address _receiver,
        address _receiveLib,
        bytes32 _payloadHash
    ) external view returns (bool);

    function executable(Origin calldata _origin, address _receiver) external view returns (ExecutionState);

    function lzReceive(
        Origin calldata _origin,
        address _receiver,
        bytes32 _guid,
        bytes calldata _message,
        bytes calldata _extraData
    ) external payable;

    // oapp can burn messages partially by calling this function with its own business logic if messages are verified in order
    function clear(address _oapp, Origin calldata _origin, bytes32 _guid, bytes calldata _message) external;

    function setLzToken(address _lzToken) external;

    function lzToken() external view returns (address);

    function nativeToken() external view returns (address);

    function setDelegate(address _delegate) external;
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

import { Origin } from "./ILayerZeroEndpointV2.sol";

interface ILayerZeroReceiver {
    function allowInitializePath(Origin calldata _origin) external view returns (bool);

    // todo: move to OAppReceiver? it is just convention for executor. we may can change it in a new Receiver version
    function nextNonce(uint32 _eid, bytes32 _sender) external view returns (uint64);

    function lzReceive(
        Origin calldata _origin,
        bytes32 _guid,
        bytes calldata _message,
        address _executor,
        bytes calldata _extraData
    ) external payable;
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";

import { SetConfigParam } from "./IMessageLibManager.sol";

enum MessageLibType {
    Send,
    Receive,
    SendAndReceive
}

interface IMessageLib is IERC165 {
    function setConfig(address _oapp, SetConfigParam[] calldata _config) external;

    function getConfig(uint32 _eid, address _oapp, uint32 _configType) external view returns (bytes memory config);

    function isSupportedEid(uint32 _eid) external view returns (bool);

    // message libs of same major version are compatible
    function version() external view returns (uint64 major, uint8 minor, uint8 endpointVersion);

    function messageLibType() external view returns (MessageLibType);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

struct SetConfigParam {
    uint32 eid;
    uint32 configType;
    bytes config;
}

interface IMessageLibManager {
    struct Timeout {
        address lib;
        uint256 expiry;
    }

    event LibraryRegistered(address newLib);
    event DefaultSendLibrarySet(uint32 eid, address newLib);
    event DefaultReceiveLibrarySet(uint32 eid, address oldLib, address newLib);
    event DefaultReceiveLibraryTimeoutSet(uint32 eid, address oldLib, uint256 expiry);
    event SendLibrarySet(address sender, uint32 eid, address newLib);
    event ReceiveLibrarySet(address receiver, uint32 eid, address oldLib, address newLib);
    event ReceiveLibraryTimeoutSet(address receiver, uint32 eid, address oldLib, uint256 timeout);

    function registerLibrary(address _lib) external;

    function isRegisteredLibrary(address _lib) external view returns (bool);

    function getRegisteredLibraries() external view returns (address[] memory);

    function setDefaultSendLibrary(uint32 _eid, address _newLib) external;

    function defaultSendLibrary(uint32 _eid) external view returns (address);

    function setDefaultReceiveLibrary(uint32 _eid, address _newLib, uint256 _timeout) external;

    function defaultReceiveLibrary(uint32 _eid) external view returns (address);

    function setDefaultReceiveLibraryTimeout(uint32 _eid, address _lib, uint256 _expiry) external;

    function defaultReceiveLibraryTimeout(uint32 _eid) external view returns (address lib, uint256 expiry);

    function isSupportedEid(uint32 _eid) external view returns (bool);

    /// ------------------- OApp interfaces -------------------
    function setSendLibrary(address _oapp, uint32 _eid, address _newLib) external;

    function getSendLibrary(address _sender, uint32 _eid) external view returns (address lib);

    function isDefaultSendLibrary(address _sender, uint32 _eid) external view returns (bool);

    function setReceiveLibrary(address _oapp, uint32 _eid, address _newLib, uint256 _gracePeriod) external;

    function getReceiveLibrary(address _receiver, uint32 _eid) external view returns (address lib, bool isDefault);

    function setReceiveLibraryTimeout(address _oapp, uint32 _eid, address _lib, uint256 _gracePeriod) external;

    function receiveLibraryTimeout(address _receiver, uint32 _eid) external view returns (address lib, uint256 expiry);

    function setConfig(address _oapp, address _lib, SetConfigParam[] calldata _params) external;

    function getConfig(
        address _oapp,
        address _lib,
        uint32 _eid,
        uint32 _configType
    ) external view returns (bytes memory config);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

interface IMessagingChannel {
    event InboundNonceSkipped(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce);
    event PacketNilified(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash);
    event PacketBurnt(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash);

    function eid() external view returns (uint32);

    // this is an emergency function if a message cannot be verified for some reasons
    // required to provide _nextNonce to avoid race condition
    function skip(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce) external;

    function nilify(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce, bytes32 _payloadHash) external;

    function burn(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce, bytes32 _payloadHash) external;

    function nextGuid(address _sender, uint32 _dstEid, bytes32 _receiver) external view returns (bytes32);

    function inboundNonce(address _receiver, uint32 _srcEid, bytes32 _sender) external view returns (uint64);

    function outboundNonce(address _sender, uint32 _dstEid, bytes32 _receiver) external view returns (uint64);

    function inboundPayloadHash(
        address _receiver,
        uint32 _srcEid,
        bytes32 _sender,
        uint64 _nonce
    ) external view returns (bytes32);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

interface IMessagingComposer {
    event ComposeSent(address from, address to, bytes32 guid, uint16 index, bytes message);
    event ComposeDelivered(address from, address to, bytes32 guid, uint16 index);
    event LzComposeAlert(
        address indexed from,
        address indexed to,
        address indexed executor,
        bytes32 guid,
        uint16 index,
        uint256 gas,
        uint256 value,
        bytes message,
        bytes extraData,
        bytes reason
    );

    function composeQueue(
        address _from,
        address _to,
        bytes32 _guid,
        uint16 _index
    ) external view returns (bytes32 messageHash);

    function sendCompose(address _to, bytes32 _guid, uint16 _index, bytes calldata _message) external;

    function lzCompose(
        address _from,
        address _to,
        bytes32 _guid,
        uint16 _index,
        bytes calldata _message,
        bytes calldata _extraData
    ) external payable;
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

interface IMessagingContext {
    function isSendingMessage() external view returns (bool);

    function getSendContext() external view returns (uint32 dstEid, address sender);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

import { MessagingFee } from "./ILayerZeroEndpointV2.sol";
import { IMessageLib } from "./IMessageLib.sol";

struct Packet {
    uint64 nonce;
    uint32 srcEid;
    address sender;
    uint32 dstEid;
    bytes32 receiver;
    bytes32 guid;
    bytes message;
}

interface ISendLib is IMessageLib {
    function send(
        Packet calldata _packet,
        bytes calldata _options,
        bool _payInLzToken
    ) external returns (MessagingFee memory, bytes memory encodedPacket);

    function quote(
        Packet calldata _packet,
        bytes calldata _options,
        bool _payInLzToken
    ) external view returns (MessagingFee memory);

    function setTreasury(address _treasury) external;

    function withdrawFee(address _to, uint256 _amount) external;

    function withdrawLzTokenFee(address _lzToken, address _to, uint256 _amount) external;
}

// SPDX-License-Identifier: LZBL-1.2

pragma solidity ^0.8.22;

import { Errors } from "./Errors.sol";

library AddressCast {
    function toBytes32(bytes calldata _addressBytes) internal pure returns (bytes32 result) {
        if (_addressBytes.length > 32) revert Errors.InvalidAddress();
        result = bytes32(_addressBytes);
        unchecked {
            uint256 offset = 32 - _addressBytes.length;
            result = result >> (offset * 8);
        }
    }

    function toBytes32(address _address) internal pure returns (bytes32 result) {
        result = bytes32(uint256(uint160(_address)));
    }

    function toBytes(bytes32 _addressBytes32, uint256 _size) internal pure returns (bytes memory result) {
        if (_size == 0 || _size > 32) revert Errors.InvalidSizeForAddress();
        result = new bytes(_size);
        unchecked {
            uint256 offset = 256 - _size * 8;
            assembly {
                mstore(add(result, 32), shl(offset, _addressBytes32))
            }
        }
    }

    function toAddress(bytes32 _addressBytes32) internal pure returns (address result) {
        result = address(uint160(uint256(_addressBytes32)));
    }

    function toAddress(bytes calldata _addressBytes) internal pure returns (address result) {
        if (_addressBytes.length != 20) revert Errors.InvalidAddress();
        result = address(bytes20(_addressBytes));
    }
}

// SPDX-License-Identifier: LZBL-1.2

pragma solidity ^0.8.22;

library Errors {
    error LzTokenUnavailable();
    error OnlyAltToken();
    error InvalidReceiveLibrary();
    error InvalidNonce(uint64 nonce);
    error InvalidArgument();
    error InvalidExpiry();
    error InvalidAmount(uint256 required, uint256 supplied);
    error OnlyRegisteredOrDefaultLib();
    error OnlyRegisteredLib();
    error OnlyNonDefaultLib();
    error Unauthorized();
    error DefaultSendLibUnavailable();
    error DefaultReceiveLibUnavailable();
    error PathNotInitializable();
    error PathNotVerifiable();
    error OnlySendLib();
    error OnlyReceiveLib();
    error UnsupportedEid();
    error UnsupportedInterface();
    error AlreadyRegistered();
    error SameValue();
    error InvalidPayloadHash();
    error PayloadHashNotFound(bytes32 expected, bytes32 actual);
    error ComposeNotFound(bytes32 expected, bytes32 actual);
    error ComposeExists();
    error SendReentrancy();
    error NotImplemented();
    error InvalidAddress();
    error InvalidSizeForAddress();
    error InsufficientFee(
        uint256 requiredNative,
        uint256 suppliedNative,
        uint256 requiredLzToken,
        uint256 suppliedLzToken
    );
    error ZeroLzTokenFee();
}

// SPDX-License-Identifier: LZBL-1.2

pragma solidity ^0.8.22;

import { Packet } from "../../interfaces/ISendLib.sol";
import { AddressCast } from "../../libs/AddressCast.sol";

library PacketV1Codec {
    using AddressCast for address;
    using AddressCast for bytes32;

    uint8 internal constant PACKET_VERSION = 1;

    // header (version + nonce + path)
    // version
    uint256 private constant PACKET_VERSION_OFFSET = 0;
    //    nonce
    uint256 private constant NONCE_OFFSET = 1;
    //    path
    uint256 private constant SRC_EID_OFFSET = 9;
    uint256 private constant SENDER_OFFSET = 13;
    uint256 private constant DST_EID_OFFSET = 45;
    uint256 private constant RECEIVER_OFFSET = 49;
    // payload (guid + message)
    uint256 private constant GUID_OFFSET = 81; // keccak256(nonce + path)
    uint256 private constant MESSAGE_OFFSET = 113;

    function encode(Packet memory _packet) internal pure returns (bytes memory encodedPacket) {
        encodedPacket = abi.encodePacked(
            PACKET_VERSION,
            _packet.nonce,
            _packet.srcEid,
            _packet.sender.toBytes32(),
            _packet.dstEid,
            _packet.receiver,
            _packet.guid,
            _packet.message
        );
    }

    function encodePacketHeader(Packet memory _packet) internal pure returns (bytes memory) {
        return
            abi.encodePacked(
                PACKET_VERSION,
                _packet.nonce,
                _packet.srcEid,
                _packet.sender.toBytes32(),
                _packet.dstEid,
                _packet.receiver
            );
    }

    function encodePayload(Packet memory _packet) internal pure returns (bytes memory) {
        return abi.encodePacked(_packet.guid, _packet.message);
    }

    function header(bytes calldata _packet) internal pure returns (bytes calldata) {
        return _packet[0:GUID_OFFSET];
    }

    function version(bytes calldata _packet) internal pure returns (uint8) {
        return uint8(bytes1(_packet[PACKET_VERSION_OFFSET:NONCE_OFFSET]));
    }

    function nonce(bytes calldata _packet) internal pure returns (uint64) {
        return uint64(bytes8(_packet[NONCE_OFFSET:SRC_EID_OFFSET]));
    }

    function srcEid(bytes calldata _packet) internal pure returns (uint32) {
        return uint32(bytes4(_packet[SRC_EID_OFFSET:SENDER_OFFSET]));
    }

    function sender(bytes calldata _packet) internal pure returns (bytes32) {
        return bytes32(_packet[SENDER_OFFSET:DST_EID_OFFSET]);
    }

    function senderAddressB20(bytes calldata _packet) internal pure returns (address) {
        return sender(_packet).toAddress();
    }

    function dstEid(bytes calldata _packet) internal pure returns (uint32) {
        return uint32(bytes4(_packet[DST_EID_OFFSET:RECEIVER_OFFSET]));
    }

    function receiver(bytes calldata _packet) internal pure returns (bytes32) {
        return bytes32(_packet[RECEIVER_OFFSET:GUID_OFFSET]);
    }

    function receiverB20(bytes calldata _packet) internal pure returns (address) {
        return receiver(_packet).toAddress();
    }

    function guid(bytes calldata _packet) internal pure returns (bytes32) {
        return bytes32(_packet[GUID_OFFSET:MESSAGE_OFFSET]);
    }

    function message(bytes calldata _packet) internal pure returns (bytes calldata) {
        return bytes(_packet[MESSAGE_OFFSET:]);
    }

    function payload(bytes calldata _packet) internal pure returns (bytes calldata) {
        return bytes(_packet[GUID_OFFSET:]);
    }

    function payloadHash(bytes calldata _packet) internal pure returns (bytes32) {
        return keccak256(payload(_packet));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 amount) external returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     *
     * CAUTION: See Security Considerations above.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/IERC20Permit.sol";
import "../../../utils/Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
     * Revert on invalid signature.
     */
    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SafeCast.sol)
// This file was procedurally generated from scripts/generate/templates/SafeCast.js.

pragma solidity ^0.8.0;

/**
 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
 * checks.
 *
 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
 * easily result in undesired exploitation or bugs, since developers usually
 * assume that overflows raise errors. `SafeCast` restores this intuition by
 * reverting the transaction when such an operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 *
 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
 * all math on `uint256` and `int256` and then downcasting.
 */
library SafeCast {
    /**
     * @dev Returns the downcasted uint248 from uint256, reverting on
     * overflow (when the input is greater than largest uint248).
     *
     * Counterpart to Solidity's `uint248` operator.
     *
     * Requirements:
     *
     * - input must fit into 248 bits
     *
     * _Available since v4.7._
     */
    function toUint248(uint256 value) internal pure returns (uint248) {
        require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits");
        return uint248(value);
    }

    /**
     * @dev Returns the downcasted uint240 from uint256, reverting on
     * overflow (when the input is greater than largest uint240).
     *
     * Counterpart to Solidity's `uint240` operator.
     *
     * Requirements:
     *
     * - input must fit into 240 bits
     *
     * _Available since v4.7._
     */
    function toUint240(uint256 value) internal pure returns (uint240) {
        require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits");
        return uint240(value);
    }

    /**
     * @dev Returns the downcasted uint232 from uint256, reverting on
     * overflow (when the input is greater than largest uint232).
     *
     * Counterpart to Solidity's `uint232` operator.
     *
     * Requirements:
     *
     * - input must fit into 232 bits
     *
     * _Available since v4.7._
     */
    function toUint232(uint256 value) internal pure returns (uint232) {
        require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits");
        return uint232(value);
    }

    /**
     * @dev Returns the downcasted uint224 from uint256, reverting on
     * overflow (when the input is greater than largest uint224).
     *
     * Counterpart to Solidity's `uint224` operator.
     *
     * Requirements:
     *
     * - input must fit into 224 bits
     *
     * _Available since v4.2._
     */
    function toUint224(uint256 value) internal pure returns (uint224) {
        require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
        return uint224(value);
    }

    /**
     * @dev Returns the downcasted uint216 from uint256, reverting on
     * overflow (when the input is greater than largest uint216).
     *
     * Counterpart to Solidity's `uint216` operator.
     *
     * Requirements:
     *
     * - input must fit into 216 bits
     *
     * _Available since v4.7._
     */
    function toUint216(uint256 value) internal pure returns (uint216) {
        require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits");
        return uint216(value);
    }

    /**
     * @dev Returns the downcasted uint208 from uint256, reverting on
     * overflow (when the input is greater than largest uint208).
     *
     * Counterpart to Solidity's `uint208` operator.
     *
     * Requirements:
     *
     * - input must fit into 208 bits
     *
     * _Available since v4.7._
     */
    function toUint208(uint256 value) internal pure returns (uint208) {
        require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits");
        return uint208(value);
    }

    /**
     * @dev Returns the downcasted uint200 from uint256, reverting on
     * overflow (when the input is greater than largest uint200).
     *
     * Counterpart to Solidity's `uint200` operator.
     *
     * Requirements:
     *
     * - input must fit into 200 bits
     *
     * _Available since v4.7._
     */
    function toUint200(uint256 value) internal pure returns (uint200) {
        require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits");
        return uint200(value);
    }

    /**
     * @dev Returns the downcasted uint192 from uint256, reverting on
     * overflow (when the input is greater than largest uint192).
     *
     * Counterpart to Solidity's `uint192` operator.
     *
     * Requirements:
     *
     * - input must fit into 192 bits
     *
     * _Available since v4.7._
     */
    function toUint192(uint256 value) internal pure returns (uint192) {
        require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits");
        return uint192(value);
    }

    /**
     * @dev Returns the downcasted uint184 from uint256, reverting on
     * overflow (when the input is greater than largest uint184).
     *
     * Counterpart to Solidity's `uint184` operator.
     *
     * Requirements:
     *
     * - input must fit into 184 bits
     *
     * _Available since v4.7._
     */
    function toUint184(uint256 value) internal pure returns (uint184) {
        require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits");
        return uint184(value);
    }

    /**
     * @dev Returns the downcasted uint176 from uint256, reverting on
     * overflow (when the input is greater than largest uint176).
     *
     * Counterpart to Solidity's `uint176` operator.
     *
     * Requirements:
     *
     * - input must fit into 176 bits
     *
     * _Available since v4.7._
     */
    function toUint176(uint256 value) internal pure returns (uint176) {
        require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits");
        return uint176(value);
    }

    /**
     * @dev Returns the downcasted uint168 from uint256, reverting on
     * overflow (when the input is greater than largest uint168).
     *
     * Counterpart to Solidity's `uint168` operator.
     *
     * Requirements:
     *
     * - input must fit into 168 bits
     *
     * _Available since v4.7._
     */
    function toUint168(uint256 value) internal pure returns (uint168) {
        require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits");
        return uint168(value);
    }

    /**
     * @dev Returns the downcasted uint160 from uint256, reverting on
     * overflow (when the input is greater than largest uint160).
     *
     * Counterpart to Solidity's `uint160` operator.
     *
     * Requirements:
     *
     * - input must fit into 160 bits
     *
     * _Available since v4.7._
     */
    function toUint160(uint256 value) internal pure returns (uint160) {
        require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits");
        return uint160(value);
    }

    /**
     * @dev Returns the downcasted uint152 from uint256, reverting on
     * overflow (when the input is greater than largest uint152).
     *
     * Counterpart to Solidity's `uint152` operator.
     *
     * Requirements:
     *
     * - input must fit into 152 bits
     *
     * _Available since v4.7._
     */
    function toUint152(uint256 value) internal pure returns (uint152) {
        require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits");
        return uint152(value);
    }

    /**
     * @dev Returns the downcasted uint144 from uint256, reverting on
     * overflow (when the input is greater than largest uint144).
     *
     * Counterpart to Solidity's `uint144` operator.
     *
     * Requirements:
     *
     * - input must fit into 144 bits
     *
     * _Available since v4.7._
     */
    function toUint144(uint256 value) internal pure returns (uint144) {
        require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits");
        return uint144(value);
    }

    /**
     * @dev Returns the downcasted uint136 from uint256, reverting on
     * overflow (when the input is greater than largest uint136).
     *
     * Counterpart to Solidity's `uint136` operator.
     *
     * Requirements:
     *
     * - input must fit into 136 bits
     *
     * _Available since v4.7._
     */
    function toUint136(uint256 value) internal pure returns (uint136) {
        require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits");
        return uint136(value);
    }

    /**
     * @dev Returns the downcasted uint128 from uint256, reverting on
     * overflow (when the input is greater than largest uint128).
     *
     * Counterpart to Solidity's `uint128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v2.5._
     */
    function toUint128(uint256 value) internal pure returns (uint128) {
        require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
        return uint128(value);
    }

    /**
     * @dev Returns the downcasted uint120 from uint256, reverting on
     * overflow (when the input is greater than largest uint120).
     *
     * Counterpart to Solidity's `uint120` operator.
     *
     * Requirements:
     *
     * - input must fit into 120 bits
     *
     * _Available since v4.7._
     */
    function toUint120(uint256 value) internal pure returns (uint120) {
        require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits");
        return uint120(value);
    }

    /**
     * @dev Returns the downcasted uint112 from uint256, reverting on
     * overflow (when the input is greater than largest uint112).
     *
     * Counterpart to Solidity's `uint112` operator.
     *
     * Requirements:
     *
     * - input must fit into 112 bits
     *
     * _Available since v4.7._
     */
    function toUint112(uint256 value) internal pure returns (uint112) {
        require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits");
        return uint112(value);
    }

    /**
     * @dev Returns the downcasted uint104 from uint256, reverting on
     * overflow (when the input is greater than largest uint104).
     *
     * Counterpart to Solidity's `uint104` operator.
     *
     * Requirements:
     *
     * - input must fit into 104 bits
     *
     * _Available since v4.7._
     */
    function toUint104(uint256 value) internal pure returns (uint104) {
        require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits");
        return uint104(value);
    }

    /**
     * @dev Returns the downcasted uint96 from uint256, reverting on
     * overflow (when the input is greater than largest uint96).
     *
     * Counterpart to Solidity's `uint96` operator.
     *
     * Requirements:
     *
     * - input must fit into 96 bits
     *
     * _Available since v4.2._
     */
    function toUint96(uint256 value) internal pure returns (uint96) {
        require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
        return uint96(value);
    }

    /**
     * @dev Returns the downcasted uint88 from uint256, reverting on
     * overflow (when the input is greater than largest uint88).
     *
     * Counterpart to Solidity's `uint88` operator.
     *
     * Requirements:
     *
     * - input must fit into 88 bits
     *
     * _Available since v4.7._
     */
    function toUint88(uint256 value) internal pure returns (uint88) {
        require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits");
        return uint88(value);
    }

    /**
     * @dev Returns the downcasted uint80 from uint256, reverting on
     * overflow (when the input is greater than largest uint80).
     *
     * Counterpart to Solidity's `uint80` operator.
     *
     * Requirements:
     *
     * - input must fit into 80 bits
     *
     * _Available since v4.7._
     */
    function toUint80(uint256 value) internal pure returns (uint80) {
        require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits");
        return uint80(value);
    }

    /**
     * @dev Returns the downcasted uint72 from uint256, reverting on
     * overflow (when the input is greater than largest uint72).
     *
     * Counterpart to Solidity's `uint72` operator.
     *
     * Requirements:
     *
     * - input must fit into 72 bits
     *
     * _Available since v4.7._
     */
    function toUint72(uint256 value) internal pure returns (uint72) {
        require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits");
        return uint72(value);
    }

    /**
     * @dev Returns the downcasted uint64 from uint256, reverting on
     * overflow (when the input is greater than largest uint64).
     *
     * Counterpart to Solidity's `uint64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v2.5._
     */
    function toUint64(uint256 value) internal pure returns (uint64) {
        require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
        return uint64(value);
    }

    /**
     * @dev Returns the downcasted uint56 from uint256, reverting on
     * overflow (when the input is greater than largest uint56).
     *
     * Counterpart to Solidity's `uint56` operator.
     *
     * Requirements:
     *
     * - input must fit into 56 bits
     *
     * _Available since v4.7._
     */
    function toUint56(uint256 value) internal pure returns (uint56) {
        require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits");
        return uint56(value);
    }

    /**
     * @dev Returns the downcasted uint48 from uint256, reverting on
     * overflow (when the input is greater than largest uint48).
     *
     * Counterpart to Solidity's `uint48` operator.
     *
     * Requirements:
     *
     * - input must fit into 48 bits
     *
     * _Available since v4.7._
     */
    function toUint48(uint256 value) internal pure returns (uint48) {
        require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits");
        return uint48(value);
    }

    /**
     * @dev Returns the downcasted uint40 from uint256, reverting on
     * overflow (when the input is greater than largest uint40).
     *
     * Counterpart to Solidity's `uint40` operator.
     *
     * Requirements:
     *
     * - input must fit into 40 bits
     *
     * _Available since v4.7._
     */
    function toUint40(uint256 value) internal pure returns (uint40) {
        require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits");
        return uint40(value);
    }

    /**
     * @dev Returns the downcasted uint32 from uint256, reverting on
     * overflow (when the input is greater than largest uint32).
     *
     * Counterpart to Solidity's `uint32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v2.5._
     */
    function toUint32(uint256 value) internal pure returns (uint32) {
        require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
        return uint32(value);
    }

    /**
     * @dev Returns the downcasted uint24 from uint256, reverting on
     * overflow (when the input is greater than largest uint24).
     *
     * Counterpart to Solidity's `uint24` operator.
     *
     * Requirements:
     *
     * - input must fit into 24 bits
     *
     * _Available since v4.7._
     */
    function toUint24(uint256 value) internal pure returns (uint24) {
        require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits");
        return uint24(value);
    }

    /**
     * @dev Returns the downcasted uint16 from uint256, reverting on
     * overflow (when the input is greater than largest uint16).
     *
     * Counterpart to Solidity's `uint16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v2.5._
     */
    function toUint16(uint256 value) internal pure returns (uint16) {
        require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
        return uint16(value);
    }

    /**
     * @dev Returns the downcasted uint8 from uint256, reverting on
     * overflow (when the input is greater than largest uint8).
     *
     * Counterpart to Solidity's `uint8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits
     *
     * _Available since v2.5._
     */
    function toUint8(uint256 value) internal pure returns (uint8) {
        require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
        return uint8(value);
    }

    /**
     * @dev Converts a signed int256 into an unsigned uint256.
     *
     * Requirements:
     *
     * - input must be greater than or equal to 0.
     *
     * _Available since v3.0._
     */
    function toUint256(int256 value) internal pure returns (uint256) {
        require(value >= 0, "SafeCast: value must be positive");
        return uint256(value);
    }

    /**
     * @dev Returns the downcasted int248 from int256, reverting on
     * overflow (when the input is less than smallest int248 or
     * greater than largest int248).
     *
     * Counterpart to Solidity's `int248` operator.
     *
     * Requirements:
     *
     * - input must fit into 248 bits
     *
     * _Available since v4.7._
     */
    function toInt248(int256 value) internal pure returns (int248 downcasted) {
        downcasted = int248(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 248 bits");
    }

    /**
     * @dev Returns the downcasted int240 from int256, reverting on
     * overflow (when the input is less than smallest int240 or
     * greater than largest int240).
     *
     * Counterpart to Solidity's `int240` operator.
     *
     * Requirements:
     *
     * - input must fit into 240 bits
     *
     * _Available since v4.7._
     */
    function toInt240(int256 value) internal pure returns (int240 downcasted) {
        downcasted = int240(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 240 bits");
    }

    /**
     * @dev Returns the downcasted int232 from int256, reverting on
     * overflow (when the input is less than smallest int232 or
     * greater than largest int232).
     *
     * Counterpart to Solidity's `int232` operator.
     *
     * Requirements:
     *
     * - input must fit into 232 bits
     *
     * _Available since v4.7._
     */
    function toInt232(int256 value) internal pure returns (int232 downcasted) {
        downcasted = int232(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 232 bits");
    }

    /**
     * @dev Returns the downcasted int224 from int256, reverting on
     * overflow (when the input is less than smallest int224 or
     * greater than largest int224).
     *
     * Counterpart to Solidity's `int224` operator.
     *
     * Requirements:
     *
     * - input must fit into 224 bits
     *
     * _Available since v4.7._
     */
    function toInt224(int256 value) internal pure returns (int224 downcasted) {
        downcasted = int224(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 224 bits");
    }

    /**
     * @dev Returns the downcasted int216 from int256, reverting on
     * overflow (when the input is less than smallest int216 or
     * greater than largest int216).
     *
     * Counterpart to Solidity's `int216` operator.
     *
     * Requirements:
     *
     * - input must fit into 216 bits
     *
     * _Available since v4.7._
     */
    function toInt216(int256 value) internal pure returns (int216 downcasted) {
        downcasted = int216(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 216 bits");
    }

    /**
     * @dev Returns the downcasted int208 from int256, reverting on
     * overflow (when the input is less than smallest int208 or
     * greater than largest int208).
     *
     * Counterpart to Solidity's `int208` operator.
     *
     * Requirements:
     *
     * - input must fit into 208 bits
     *
     * _Available since v4.7._
     */
    function toInt208(int256 value) internal pure returns (int208 downcasted) {
        downcasted = int208(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 208 bits");
    }

    /**
     * @dev Returns the downcasted int200 from int256, reverting on
     * overflow (when the input is less than smallest int200 or
     * greater than largest int200).
     *
     * Counterpart to Solidity's `int200` operator.
     *
     * Requirements:
     *
     * - input must fit into 200 bits
     *
     * _Available since v4.7._
     */
    function toInt200(int256 value) internal pure returns (int200 downcasted) {
        downcasted = int200(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 200 bits");
    }

    /**
     * @dev Returns the downcasted int192 from int256, reverting on
     * overflow (when the input is less than smallest int192 or
     * greater than largest int192).
     *
     * Counterpart to Solidity's `int192` operator.
     *
     * Requirements:
     *
     * - input must fit into 192 bits
     *
     * _Available since v4.7._
     */
    function toInt192(int256 value) internal pure returns (int192 downcasted) {
        downcasted = int192(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 192 bits");
    }

    /**
     * @dev Returns the downcasted int184 from int256, reverting on
     * overflow (when the input is less than smallest int184 or
     * greater than largest int184).
     *
     * Counterpart to Solidity's `int184` operator.
     *
     * Requirements:
     *
     * - input must fit into 184 bits
     *
     * _Available since v4.7._
     */
    function toInt184(int256 value) internal pure returns (int184 downcasted) {
        downcasted = int184(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 184 bits");
    }

    /**
     * @dev Returns the downcasted int176 from int256, reverting on
     * overflow (when the input is less than smallest int176 or
     * greater than largest int176).
     *
     * Counterpart to Solidity's `int176` operator.
     *
     * Requirements:
     *
     * - input must fit into 176 bits
     *
     * _Available since v4.7._
     */
    function toInt176(int256 value) internal pure returns (int176 downcasted) {
        downcasted = int176(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 176 bits");
    }

    /**
     * @dev Returns the downcasted int168 from int256, reverting on
     * overflow (when the input is less than smallest int168 or
     * greater than largest int168).
     *
     * Counterpart to Solidity's `int168` operator.
     *
     * Requirements:
     *
     * - input must fit into 168 bits
     *
     * _Available since v4.7._
     */
    function toInt168(int256 value) internal pure returns (int168 downcasted) {
        downcasted = int168(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 168 bits");
    }

    /**
     * @dev Returns the downcasted int160 from int256, reverting on
     * overflow (when the input is less than smallest int160 or
     * greater than largest int160).
     *
     * Counterpart to Solidity's `int160` operator.
     *
     * Requirements:
     *
     * - input must fit into 160 bits
     *
     * _Available since v4.7._
     */
    function toInt160(int256 value) internal pure returns (int160 downcasted) {
        downcasted = int160(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 160 bits");
    }

    /**
     * @dev Returns the downcasted int152 from int256, reverting on
     * overflow (when the input is less than smallest int152 or
     * greater than largest int152).
     *
     * Counterpart to Solidity's `int152` operator.
     *
     * Requirements:
     *
     * - input must fit into 152 bits
     *
     * _Available since v4.7._
     */
    function toInt152(int256 value) internal pure returns (int152 downcasted) {
        downcasted = int152(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 152 bits");
    }

    /**
     * @dev Returns the downcasted int144 from int256, reverting on
     * overflow (when the input is less than smallest int144 or
     * greater than largest int144).
     *
     * Counterpart to Solidity's `int144` operator.
     *
     * Requirements:
     *
     * - input must fit into 144 bits
     *
     * _Available since v4.7._
     */
    function toInt144(int256 value) internal pure returns (int144 downcasted) {
        downcasted = int144(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 144 bits");
    }

    /**
     * @dev Returns the downcasted int136 from int256, reverting on
     * overflow (when the input is less than smallest int136 or
     * greater than largest int136).
     *
     * Counterpart to Solidity's `int136` operator.
     *
     * Requirements:
     *
     * - input must fit into 136 bits
     *
     * _Available since v4.7._
     */
    function toInt136(int256 value) internal pure returns (int136 downcasted) {
        downcasted = int136(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 136 bits");
    }

    /**
     * @dev Returns the downcasted int128 from int256, reverting on
     * overflow (when the input is less than smallest int128 or
     * greater than largest int128).
     *
     * Counterpart to Solidity's `int128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v3.1._
     */
    function toInt128(int256 value) internal pure returns (int128 downcasted) {
        downcasted = int128(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 128 bits");
    }

    /**
     * @dev Returns the downcasted int120 from int256, reverting on
     * overflow (when the input is less than smallest int120 or
     * greater than largest int120).
     *
     * Counterpart to Solidity's `int120` operator.
     *
     * Requirements:
     *
     * - input must fit into 120 bits
     *
     * _Available since v4.7._
     */
    function toInt120(int256 value) internal pure returns (int120 downcasted) {
        downcasted = int120(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 120 bits");
    }

    /**
     * @dev Returns the downcasted int112 from int256, reverting on
     * overflow (when the input is less than smallest int112 or
     * greater than largest int112).
     *
     * Counterpart to Solidity's `int112` operator.
     *
     * Requirements:
     *
     * - input must fit into 112 bits
     *
     * _Available since v4.7._
     */
    function toInt112(int256 value) internal pure returns (int112 downcasted) {
        downcasted = int112(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 112 bits");
    }

    /**
     * @dev Returns the downcasted int104 from int256, reverting on
     * overflow (when the input is less than smallest int104 or
     * greater than largest int104).
     *
     * Counterpart to Solidity's `int104` operator.
     *
     * Requirements:
     *
     * - input must fit into 104 bits
     *
     * _Available since v4.7._
     */
    function toInt104(int256 value) internal pure returns (int104 downcasted) {
        downcasted = int104(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 104 bits");
    }

    /**
     * @dev Returns the downcasted int96 from int256, reverting on
     * overflow (when the input is less than smallest int96 or
     * greater than largest int96).
     *
     * Counterpart to Solidity's `int96` operator.
     *
     * Requirements:
     *
     * - input must fit into 96 bits
     *
     * _Available since v4.7._
     */
    function toInt96(int256 value) internal pure returns (int96 downcasted) {
        downcasted = int96(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 96 bits");
    }

    /**
     * @dev Returns the downcasted int88 from int256, reverting on
     * overflow (when the input is less than smallest int88 or
     * greater than largest int88).
     *
     * Counterpart to Solidity's `int88` operator.
     *
     * Requirements:
     *
     * - input must fit into 88 bits
     *
     * _Available since v4.7._
     */
    function toInt88(int256 value) internal pure returns (int88 downcasted) {
        downcasted = int88(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 88 bits");
    }

    /**
     * @dev Returns the downcasted int80 from int256, reverting on
     * overflow (when the input is less than smallest int80 or
     * greater than largest int80).
     *
     * Counterpart to Solidity's `int80` operator.
     *
     * Requirements:
     *
     * - input must fit into 80 bits
     *
     * _Available since v4.7._
     */
    function toInt80(int256 value) internal pure returns (int80 downcasted) {
        downcasted = int80(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 80 bits");
    }

    /**
     * @dev Returns the downcasted int72 from int256, reverting on
     * overflow (when the input is less than smallest int72 or
     * greater than largest int72).
     *
     * Counterpart to Solidity's `int72` operator.
     *
     * Requirements:
     *
     * - input must fit into 72 bits
     *
     * _Available since v4.7._
     */
    function toInt72(int256 value) internal pure returns (int72 downcasted) {
        downcasted = int72(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 72 bits");
    }

    /**
     * @dev Returns the downcasted int64 from int256, reverting on
     * overflow (when the input is less than smallest int64 or
     * greater than largest int64).
     *
     * Counterpart to Solidity's `int64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v3.1._
     */
    function toInt64(int256 value) internal pure returns (int64 downcasted) {
        downcasted = int64(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 64 bits");
    }

    /**
     * @dev Returns the downcasted int56 from int256, reverting on
     * overflow (when the input is less than smallest int56 or
     * greater than largest int56).
     *
     * Counterpart to Solidity's `int56` operator.
     *
     * Requirements:
     *
     * - input must fit into 56 bits
     *
     * _Available since v4.7._
     */
    function toInt56(int256 value) internal pure returns (int56 downcasted) {
        downcasted = int56(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 56 bits");
    }

    /**
     * @dev Returns the downcasted int48 from int256, reverting on
     * overflow (when the input is less than smallest int48 or
     * greater than largest int48).
     *
     * Counterpart to Solidity's `int48` operator.
     *
     * Requirements:
     *
     * - input must fit into 48 bits
     *
     * _Available since v4.7._
     */
    function toInt48(int256 value) internal pure returns (int48 downcasted) {
        downcasted = int48(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 48 bits");
    }

    /**
     * @dev Returns the downcasted int40 from int256, reverting on
     * overflow (when the input is less than smallest int40 or
     * greater than largest int40).
     *
     * Counterpart to Solidity's `int40` operator.
     *
     * Requirements:
     *
     * - input must fit into 40 bits
     *
     * _Available since v4.7._
     */
    function toInt40(int256 value) internal pure returns (int40 downcasted) {
        downcasted = int40(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 40 bits");
    }

    /**
     * @dev Returns the downcasted int32 from int256, reverting on
     * overflow (when the input is less than smallest int32 or
     * greater than largest int32).
     *
     * Counterpart to Solidity's `int32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v3.1._
     */
    function toInt32(int256 value) internal pure returns (int32 downcasted) {
        downcasted = int32(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 32 bits");
    }

    /**
     * @dev Returns the downcasted int24 from int256, reverting on
     * overflow (when the input is less than smallest int24 or
     * greater than largest int24).
     *
     * Counterpart to Solidity's `int24` operator.
     *
     * Requirements:
     *
     * - input must fit into 24 bits
     *
     * _Available since v4.7._
     */
    function toInt24(int256 value) internal pure returns (int24 downcasted) {
        downcasted = int24(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 24 bits");
    }

    /**
     * @dev Returns the downcasted int16 from int256, reverting on
     * overflow (when the input is less than smallest int16 or
     * greater than largest int16).
     *
     * Counterpart to Solidity's `int16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v3.1._
     */
    function toInt16(int256 value) internal pure returns (int16 downcasted) {
        downcasted = int16(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 16 bits");
    }

    /**
     * @dev Returns the downcasted int8 from int256, reverting on
     * overflow (when the input is less than smallest int8 or
     * greater than largest int8).
     *
     * Counterpart to Solidity's `int8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits
     *
     * _Available since v3.1._
     */
    function toInt8(int256 value) internal pure returns (int8 downcasted) {
        downcasted = int8(value);
        require(downcasted == value, "SafeCast: value doesn't fit in 8 bits");
    }

    /**
     * @dev Converts an unsigned uint256 into a signed int256.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxInt256.
     *
     * _Available since v3.0._
     */
    function toInt256(uint256 value) internal pure returns (int256) {
        // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
        require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
        return int256(value);
    }
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.0;

import { MessagingFee } from "@layerzerolabs/lz-evm-oapp-v2/contracts/oft/interfaces/IOFT.sol";

/// @notice Stores the information related to a batch of credit transfers.
struct TargetCreditBatch {
    uint16 assetId;
    TargetCredit[] credits;
}

/// @notice Stores the information related to a single credit transfer.
struct TargetCredit {
    uint32 srcEid;
    uint64 amount; // the amount of credits to intended to send
    uint64 minAmount; // the minimum amount of credits to keep on local chain after sending
}

/// @title Credit Messaging API
/// @dev This interface defines the API for quoting and sending credits to other chains.
interface ICreditMessaging {
    /// @notice Sends credits to the destination endpoint.
    /// @param _dstEid The destination LayerZero endpoint ID.
    /// @param _creditBatches The credit batch payloads to send to the destination LayerZero endpoint ID.
    function sendCredits(uint32 _dstEid, TargetCreditBatch[] calldata _creditBatches) external payable;

    /// @notice Quotes the fee for sending credits to the destination endpoint.
    /// @param _dstEid The destination LayerZero endpoint ID.
    /// @param _creditBatches The credit batch payloads to send to the destination LayerZero endpoint ID.
    /// @return fee The fee for sending the credits to the destination endpoint.
    function quoteSendCredits(
        uint32 _dstEid,
        TargetCreditBatch[] calldata _creditBatches
    ) external view returns (MessagingFee memory fee);
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.0;

import { TargetCredit } from "./ICreditMessaging.sol";

struct Credit {
    uint32 srcEid;
    uint64 amount;
}

/// @dev This is an internal interface, defining functions to handle messages/calls from the credit messaging contract.
interface ICreditMessagingHandler {
    function sendCredits(uint32 _dstEid, TargetCredit[] calldata _credits) external returns (Credit[] memory);

    function receiveCredits(uint32 _srcEid, Credit[] calldata _credits) external;
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.22;

import { SafeCast } from "@openzeppelin/contracts/utils/math/SafeCast.sol";
import { Buffer } from "@ensdomains/buffer/contracts/Buffer.sol";

import { Credit } from "../interfaces/ICreditMessagingHandler.sol";

struct CreditBatch {
    uint16 assetId;
    Credit[] credits;
}

library CreditMsgCodec {
    using Buffer for Buffer.buffer;
    using SafeCast for uint256;

    /// @dev The byte width of the amount field in the credit message.
    uint8 internal constant AMOUNT_BYTE_WIDTH = 8;

    /// @dev The byte width of the assetId field in the credit message.
    uint8 internal constant ASSET_ID_BYTE_WIDTH = 2;

    /// @dev The byte width of the srcEid field in the credit message.
    uint8 internal constant EID_BYTE_WIDTH = 4;

    /// @dev The byte width of the numBatches field in the credit message.
    uint8 internal constant NUM_BATCHES_BYTE_WIDTH = 1;

    /// @dev The byte width of the numCredits field in the credit batch.
    uint8 internal constant NUM_CREDITS_BYTE_WIDTH = 1;

    error CreditMsgCodec_InvalidMessage();

    function encode(
        CreditBatch[] memory _creditBatches,
        uint256 _totalCreditNum
    ) internal pure returns (bytes memory message) {
        uint256 numBatches = _creditBatches.length;
        // batchNum(1) + batchNum * (assetId(2) + batchSize(1)) + creditNum * (srcEid(4) + amount(8))
        uint256 bufferSize = NUM_BATCHES_BYTE_WIDTH +
            numBatches *
            (NUM_CREDITS_BYTE_WIDTH + ASSET_ID_BYTE_WIDTH) +
            _totalCreditNum *
            (EID_BYTE_WIDTH + AMOUNT_BYTE_WIDTH);
        Buffer.buffer memory buf;
        buf.init(bufferSize);
        buf.appendUint8(numBatches.toUint8());
        for (uint256 i = 0; i < numBatches; i++) {
            CreditBatch memory batch = _creditBatches[i];
            buf.appendInt(batch.assetId, ASSET_ID_BYTE_WIDTH);
            uint256 batchSize = batch.credits.length;
            buf.appendUint8(batchSize.toUint8());
            for (uint256 j = 0; j < batchSize; j++) {
                Credit memory credit = batch.credits[j];
                buf.appendInt(credit.srcEid, EID_BYTE_WIDTH);
                buf.appendInt(credit.amount, AMOUNT_BYTE_WIDTH);
            }
        }
        message = buf.buf;
    }

    function decode(bytes calldata _message) internal pure returns (CreditBatch[] memory creditBatches) {
        uint8 batchNum = uint8(_message[0]);
        creditBatches = new CreditBatch[](batchNum);
        uint256 cursor = 1; // skip batchNum(1)
        for (uint256 i = 0; i < batchNum; i++) {
            uint16 assetId = uint16(bytes2(_message[cursor:cursor += ASSET_ID_BYTE_WIDTH]));
            uint8 batchSize = uint8(_message[cursor]);
            cursor += NUM_BATCHES_BYTE_WIDTH;
            Credit[] memory credits = new Credit[](batchSize);
            for (uint256 j = 0; j < batchSize; j++) {
                uint32 srcEid = uint32(bytes4(_message[cursor:cursor += EID_BYTE_WIDTH]));
                uint64 amount = uint64(bytes8(_message[cursor:cursor += AMOUNT_BYTE_WIDTH]));
                credits[j] = Credit(srcEid, amount);
            }
            creditBatches[i] = CreditBatch(assetId, credits);
        }
        if (cursor != _message.length) revert CreditMsgCodec_InvalidMessage();
    }
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.22;

import { MessagingFee } from "@layerzerolabs/lz-evm-oapp-v2/contracts/oft/interfaces/IOFT.sol";

import { ICreditMessaging, TargetCreditBatch, TargetCredit } from "../interfaces/ICreditMessaging.sol";
import { ICreditMessagingHandler, Credit } from "../interfaces/ICreditMessagingHandler.sol";
import { CreditMsgCodec, CreditBatch } from "../libs/CreditMsgCodec.sol";
import { CreditMessagingOptions } from "./CreditMessagingOptions.sol";
import { MessagingBase, Origin } from "./MessagingBase.sol";

contract CreditMessaging is MessagingBase, CreditMessagingOptions, ICreditMessaging {
    constructor(address _endpoint, address _owner) MessagingBase(_endpoint, _owner) {}

    // ---------------------------------- Only Planner ------------------------------------------

    function sendCredits(uint32 _dstEid, TargetCreditBatch[] calldata _creditBatches) external payable onlyPlanner {
        CreditBatch[] memory batches = new CreditBatch[](_creditBatches.length);
        uint256 index = 0;
        uint128 totalCreditNum = 0; // total number of credits in all batches

        for (uint256 i = 0; i < _creditBatches.length; i++) {
            TargetCreditBatch calldata targetBatch = _creditBatches[i];
            Credit[] memory actualCredits = ICreditMessagingHandler(_safeGetStargateImpl(targetBatch.assetId))
                .sendCredits(_dstEid, targetBatch.credits);
            if (actualCredits.length > 0) {
                batches[index++] = CreditBatch(targetBatch.assetId, actualCredits);
                totalCreditNum += uint128(actualCredits.length); // safe cast
            }
        }

        if (index != 0) {
            // resize the array to the actual number of batches
            assembly {
                mstore(batches, index)
            }
            bytes memory message = CreditMsgCodec.encode(batches, totalCreditNum);
            bytes memory options = _buildOptions(_dstEid, totalCreditNum);
            _lzSend(_dstEid, message, options, MessagingFee(msg.value, 0), msg.sender);
        }
    }

    function quoteSendCredits(
        uint32 _dstEid,
        TargetCreditBatch[] calldata _creditBatches
    ) external view returns (MessagingFee memory fee) {
        CreditBatch[] memory creditBatches = new CreditBatch[](_creditBatches.length);
        uint128 creditNum = 0; // used for message encoding
        for (uint256 i = 0; i < _creditBatches.length; i++) {
            TargetCredit[] calldata targetCredits = _creditBatches[i].credits;
            Credit[] memory credits = new Credit[](targetCredits.length);
            creditNum += uint128(targetCredits.length); // safe cast
            for (uint256 j = 0; j < targetCredits.length; j++) {
                credits[j] = Credit(targetCredits[j].srcEid, targetCredits[j].amount);
            }
            creditBatches[i] = CreditBatch(_creditBatches[i].assetId, credits);
        }
        bytes memory message = CreditMsgCodec.encode(creditBatches, creditNum);
        bytes memory options = _buildOptions(_dstEid, creditNum);
        fee = _quote(_dstEid, message, options, false);
    }

    // ---------------------------------- OApp Functions ------------------------------------------

    function _lzReceive(
        Origin calldata _origin,
        bytes32 /*_guid*/,
        bytes calldata _message,
        address /*_executor*/,
        bytes calldata /*_extraData*/
    ) internal override {
        CreditBatch[] memory creditBatches = CreditMsgCodec.decode(_message);
        uint256 batchNum = creditBatches.length;
        for (uint256 i = 0; i < batchNum; i++) {
            CreditBatch memory creditBatch = creditBatches[i];
            ICreditMessagingHandler(_safeGetStargateImpl(creditBatch.assetId)).receiveCredits(
                _origin.srcEid,
                creditBatch.credits
            );
        }
    }
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.22;

import { OAppOptionsType3 } from "@layerzerolabs/lz-evm-oapp-v2/contracts/oapp/libs/OAppOptionsType3.sol";
import { Buffer } from "@ensdomains/buffer/contracts/Buffer.sol";

/// @title Credit Messaging implementation of OAppOptionsType3
/// @notice This contract is used to build options for the CreditMessaging OApp.
abstract contract CreditMessagingOptions is OAppOptionsType3 {
    using Buffer for Buffer.buffer;

    /// @dev CreditMessaging only has one type of message.
    uint8 internal constant MSG_TYPE_CREDIT_MESSAGING = 3; // only one message type for credit messaging

    uint8 internal constant EXECUTOR_WORKER_ID = 1;
    uint8 internal constant OPTION_TYPE_LZRECEIVE = 1;
    uint16 internal constant OPTION_LZRECEIVE_PARAMS_SIZE = 17; // type(1) + gas(16)

    /// @dev The base gas limit for each endpoint.
    mapping(uint32 eid => uint128 gasLimit) public gasLimits;

    /// @notice Event emitted when the gas limit is set for a given endpoint.
    /// @param eid The LayerZero endpoint ID.
    /// @param gasLimit The base gas limit for the destination endpoint.
    event GasLimitSet(uint32 eid, uint128 gasLimit);

    /// @notice Error message for when the gas limit is not set for a given endpoint.
    /// @dev Zero gas limit is considered not set.
    error MessagingOptions_ZeroGasLimit();

    /// @notice Sets the base gas limit for a specific endpoint.  Sending a LayerZero message takes some constant amount
    /// of base gas regardless of the number of credits being sent in a particular message.  This function allows the
    /// CreditMessaging OApp to set the base gas limit.
    /// @param _eid The LayerZero endpoint ID.
    /// @param _gasLimit The base gas limit for the destination endpoint.
    function setGasLimit(uint32 _eid, uint128 _gasLimit) external onlyOwner {
        gasLimits[_eid] = _gasLimit;
        emit GasLimitSet(_eid, _gasLimit);
    }

    /// @notice Build the options for a credit messaging transaction.
    /// @param _eid The LayerZero endpoint ID.
    /// @param _totalCreditNum The total number of credits being sent in the message.
    /// @return options The options for the message.
    /// @dev The options are built by appending the lzReceive option to the enforced options for the given endpoint.
    function _buildOptions(uint32 _eid, uint128 _totalCreditNum) internal view returns (bytes memory options) {
        uint128 gasLimit = _safeGetGasLimit(_eid) * _totalCreditNum;
        options = enforcedOptions[_eid][MSG_TYPE_CREDIT_MESSAGING];

        // append lzReceive option
        options = options.length == 0
            ? abi.encodePacked(
                OPTION_TYPE_3,
                EXECUTOR_WORKER_ID,
                OPTION_LZRECEIVE_PARAMS_SIZE,
                OPTION_TYPE_LZRECEIVE,
                gasLimit
            )
            : abi.encodePacked(
                options,
                EXECUTOR_WORKER_ID,
                OPTION_LZRECEIVE_PARAMS_SIZE,
                OPTION_TYPE_LZRECEIVE,
                gasLimit
            );
    }

    /// @notice Safely retrieves the base gas limit for a given endpoint.  The base gas limit is the constant amount of
    /// gas required to send a message to the endpoint, regardless of the number of credits being sent.
    /// @param _eid The LayerZero endpoint ID.
    /// @return gasLimit The gas limit for the destination endpoint.
    /// @dev If the gas limit is not set, this function will revert.
    function _safeGetGasLimit(uint32 _eid) private view returns (uint128 gasLimit) {
        gasLimit = gasLimits[_eid];
        if (gasLimit == 0) revert MessagingOptions_ZeroGasLimit();
    }
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.22;

import { OApp, Origin } from "@layerzerolabs/lz-evm-oapp-v2/contracts/oapp/OApp.sol";
import { OAppPreCrimeSimulator } from "@layerzerolabs/lz-evm-oapp-v2/contracts/precrime/OAppPreCrimeSimulator.sol";

abstract contract MessagingBase is OApp, OAppPreCrimeSimulator {
    // max asset id, for the off-chain to get the range of asset id and get the list of stargate impls
    uint16 public maxAssetId;
    mapping(address stargateImpl => uint16 assetId) public assetIds;
    mapping(uint16 assetId => address stargateImpl) public stargateImpls;

    address public planner;

    event AssetIdSet(address stargateImpl, uint16 assetId);
    event MaxAssetIdSet(uint16 maxAssetId);
    event PlannerSet(address planner);

    error Messaging_Unauthorized();
    error Messaging_Unavailable();
    error Messaging_InvalidAssetId();

    modifier onlyPlanner() {
        if (msg.sender != planner) revert Messaging_Unauthorized();
        _;
    }

    constructor(address _endpoint, address _owner) OApp(_endpoint, _owner) {}

    // ---------------------------------- Only Owner ------------------------------------------

    function setAssetId(address _stargateImpl, uint16 _assetId) external onlyOwner {
        if (_assetId == 0) revert Messaging_InvalidAssetId();
        if (_assetId > maxAssetId) {
            maxAssetId = _assetId;
            emit MaxAssetIdSet(_assetId);
        }

        // clean up the old stargate
        uint16 oldAssetId = assetIds[_stargateImpl];
        address oldStargateImpl = stargateImpls[_assetId];
        if (oldAssetId != 0) delete stargateImpls[oldAssetId];
        if (oldStargateImpl != address(0)) delete assetIds[oldStargateImpl];

        // if stargateImpl is address(0) then delete stargateImpls[_assetId]
        if (_stargateImpl == address(0)) {
            delete stargateImpls[_assetId];
        } else {
            // set the new stargate
            assetIds[_stargateImpl] = _assetId;
            stargateImpls[_assetId] = _stargateImpl;
        }
        emit AssetIdSet(_stargateImpl, _assetId);
    }

    /// @dev Update the max asset id manually if it is not set correctly
    function setMaxAssetId(uint16 _maxAssetId) external onlyOwner {
        maxAssetId = _maxAssetId;
        emit MaxAssetIdSet(_maxAssetId);
    }

    function setPlanner(address _planner) external onlyOwner {
        planner = _planner;
        emit PlannerSet(_planner);
    }

    // ---------------------------------- Internal Functions ------------------------------------------

    function _safeGetStargateImpl(uint16 _assetId) internal view returns (address stargate) {
        stargate = stargateImpls[_assetId];
        if (stargate == address(0)) revert Messaging_Unavailable();
    }

    function _safeGetAssetId(address _stargateImpl) internal view returns (uint16 assetId) {
        assetId = assetIds[_stargateImpl];
        if (assetId == 0) revert Messaging_Unavailable();
    }

    /// @dev Lz token is payed in the stargate contract and do nothing here.
    /// Function meant to be overridden
    // solhint-disable-next-line no-empty-blocks
    function _payLzToken(uint256 /*_lzTokenFee*/) internal pure override {}

    // ---------------------------------- PreCrime Functions ------------------------------------------
    function _lzReceiveSimulate(
        Origin calldata _origin,
        bytes32 _guid,
        bytes calldata _message,
        address _executor,
        bytes calldata _extraData
    ) internal override {
        _lzReceive(_origin, _guid, _message, _executor, _extraData);
    }

    function isPeer(uint32 _eid, bytes32 _peer) public view override returns (bool) {
        return _peer == peers[_eid];
    }
}

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