// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;

interface IBridgeHook {
    /**
     * @notice Handles an incoming bridge transfer with some tokens and extra
     * data. Takes any necessary actions for the hook's purposes.
     *
     * This function is intended to allow arbitrary post-bridge actions with
     * tokens, at a user's discretion. E.g. recollateralize a CDP, exchange for
     * other tokens, emit an event, etc.
     *
     * @dev This hook is called AFTER tokens have been transferred to the hook
     * contract. If this hook errors, the bridge WILL NOT revert, and the hook
     * contract will own those tokens. Hook contracts MUST have a recovery plan
     * in place for these situations.
     *
     * @param _origin The domain of the chain from which the transfer originated
     * @param _sender The identifier of the caller which sent the tokens over the bridge
     * @param _tokenDomain The canonical deployment domain of the token
     * @param _tokenAddress The identifier for the token on its canonical domain
     * @param _localToken The local address of the token (its canonical
     *                    address if it is local to this domain, otherwise its
     *                    the address of its local representation).
     * @param _amount The amount of token received over the bridge
     * @param _extraData Extra user-specified data passed in to the origin chain
     */
    function onReceive(
        uint32 _origin,
        bytes32 _sender,
        uint32 _tokenDomain,
        bytes32 _tokenAddress,
        address _localToken,
        uint256 _amount,
        bytes memory _extraData
    ) external;
}