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/* solhint-disable */
// Sources flattened with hardhat v2.12.4 https://hardhat.org
/**
 * @notice This is a flattened contract file generated from Safe Smart Account repository v1.4.1
 * @see https://github.com/safe-global/safe-smart-account/tree/v1.4.1
 * @dev Generated using command:
 * npx hardhat flatten contracts/proxies/SafeProxyFactory.sol > flattened/SafeProxyFactory_flattened.sol
 */

// File contracts/proxies/SafeProxy.sol

/// @custom:version 1.4.1
pragma solidity >=0.7.0 <0.9.0;

/**
 * @title IProxy - Helper interface to access the singleton address of the Proxy on-chain.
 * @author Richard Meissner - @rmeissner
 */
interface IProxy {
    function masterCopy() external view returns (address);
}

/**
 * @title SafeProxy - Generic proxy contract allows to execute all transactions applying the code of a master contract.
 * @author Stefan George - <stefan@gnosis.io>
 * @author Richard Meissner - <richard@gnosis.io>
 */
contract SafeProxy {
    // Singleton always needs to be first declared variable, to ensure that it is at the same location in the contracts to which calls are delegated.
    // To reduce deployment costs this variable is internal and needs to be retrieved via `getStorageAt`
    address internal singleton;

    /**
     * @notice Constructor function sets address of singleton contract.
     * @param _singleton Singleton address.
     */
    constructor(address _singleton) {
        require(
            _singleton != address(0),
            "Invalid singleton address provided"
        );
        singleton = _singleton;
    }

    /// @dev Fallback function forwards all transactions and returns all received return data.
    fallback() external payable {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            let _singleton := and(
                sload(0),
                0xffffffffffffffffffffffffffffffffffffffff
            )
            // 0xa619486e == keccak("masterCopy()"). The value is right padded to 32-bytes with 0s
            if eq(
                calldataload(0),
                0xa619486e00000000000000000000000000000000000000000000000000000000
            ) {
                mstore(0, _singleton)
                return(0, 0x20)
            }
            calldatacopy(0, 0, calldatasize())
            let success := delegatecall(
                gas(),
                _singleton,
                0,
                calldatasize(),
                0,
                0
            )
            returndatacopy(0, 0, returndatasize())
            if eq(success, 0) {
                revert(0, returndatasize())
            }
            return(0, returndatasize())
        }
    }
}

// File contracts/proxies/IProxyCreationCallback.sol

pragma solidity >=0.7.0 <0.9.0;

/**
 * @title IProxyCreationCallback
 * @dev An interface for a contract that implements a callback function to be executed after the creation of a proxy instance.
 */
interface IProxyCreationCallback {
    /**
     * @dev Function to be called after the creation of a SafeProxy instance.
     * @param proxy The newly created SafeProxy instance.
     * @param _singleton The address of the singleton contract used to create the proxy.
     * @param initializer The initializer function call data.
     * @param saltNonce The nonce used to generate the salt for the proxy deployment.
     */
    function proxyCreated(
        SafeProxy proxy,
        address _singleton,
        bytes calldata initializer,
        uint256 saltNonce
    ) external;
}

// File contracts/proxies/SafeProxyFactory.sol

pragma solidity >=0.7.0 <0.9.0;

/**
 * @title Proxy Factory - Allows to create a new proxy contract and execute a message call to the new proxy within one transaction.
 * @author Stefan George - @Georgi87
 */
contract SafeProxyFactory {
    event ProxyCreation(SafeProxy indexed proxy, address singleton);

    /// @dev Allows to retrieve the creation code used for the Proxy deployment. With this it is easily possible to calculate predicted address.
    function proxyCreationCode() public pure returns (bytes memory) {
        return type(SafeProxy).creationCode;
    }

    /**
     * @notice Internal method to create a new proxy contract using CREATE2. Optionally executes an initializer call to a new proxy.
     * @param _singleton Address of singleton contract. Must be deployed at the time of execution.
     * @param initializer (Optional) Payload for a message call to be sent to a new proxy contract.
     * @param salt Create2 salt to use for calculating the address of the new proxy contract.
     * @return proxy Address of the new proxy contract.
     */
    function deployProxy(
        address _singleton,
        bytes memory initializer,
        bytes32 salt
    ) internal returns (SafeProxy proxy) {
        require(isContract(_singleton), "Singleton contract not deployed");

        bytes memory deploymentData = abi.encodePacked(
            type(SafeProxy).creationCode,
            uint256(uint160(_singleton))
        );
        // solhint-disable-next-line no-inline-assembly
        assembly {
            proxy := create2(
                0x0,
                add(0x20, deploymentData),
                mload(deploymentData),
                salt
            )
        }
        require(address(proxy) != address(0), "Create2 call failed");

        if (initializer.length > 0) {
            // solhint-disable-next-line no-inline-assembly
            assembly {
                if eq(
                    call(
                        gas(),
                        proxy,
                        0,
                        add(initializer, 0x20),
                        mload(initializer),
                        0,
                        0
                    ),
                    0
                ) {
                    revert(0, 0)
                }
            }
        }
    }

    /**
     * @notice Deploys a new proxy with `_singleton` singleton and `saltNonce` salt. Optionally executes an initializer call to a new proxy.
     * @param _singleton Address of singleton contract. Must be deployed at the time of execution.
     * @param initializer Payload for a message call to be sent to a new proxy contract.
     * @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
     */
    function createProxyWithNonce(
        address _singleton,
        bytes memory initializer,
        uint256 saltNonce
    ) public returns (SafeProxy proxy) {
        // If the initializer changes the proxy address should change too. Hashing the initializer data is cheaper than just concatinating it
        bytes32 salt = keccak256(
            abi.encodePacked(keccak256(initializer), saltNonce)
        );
        proxy = deployProxy(_singleton, initializer, salt);
        emit ProxyCreation(proxy, _singleton);
    }

    /**
     * @notice Deploys a new chain-specific proxy with `_singleton` singleton and `saltNonce` salt. Optionally executes an initializer call to a new proxy.
     * @dev Allows to create a new proxy contract that should exist only on 1 network (e.g. specific governance or admin accounts)
     *      by including the chain id in the create2 salt. Such proxies cannot be created on other networks by replaying the transaction.
     * @param _singleton Address of singleton contract. Must be deployed at the time of execution.
     * @param initializer Payload for a message call to be sent to a new proxy contract.
     * @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
     */
    function createChainSpecificProxyWithNonce(
        address _singleton,
        bytes memory initializer,
        uint256 saltNonce
    ) public returns (SafeProxy proxy) {
        // If the initializer changes the proxy address should change too. Hashing the initializer data is cheaper than just concatinating it
        bytes32 salt = keccak256(
            abi.encodePacked(keccak256(initializer), saltNonce, getChainId())
        );
        proxy = deployProxy(_singleton, initializer, salt);
        emit ProxyCreation(proxy, _singleton);
    }

    /**
     * @notice Deploy a new proxy with `_singleton` singleton and `saltNonce` salt.
     *         Optionally executes an initializer call to a new proxy and calls a specified callback address `callback`.
     * @param _singleton Address of singleton contract. Must be deployed at the time of execution.
     * @param initializer Payload for a message call to be sent to a new proxy contract.
     * @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
     * @param callback Callback that will be invoked after the new proxy contract has been successfully deployed and initialized.
     */
    function createProxyWithCallback(
        address _singleton,
        bytes memory initializer,
        uint256 saltNonce,
        IProxyCreationCallback callback
    ) public returns (SafeProxy proxy) {
        uint256 saltNonceWithCallback = uint256(
            keccak256(abi.encodePacked(saltNonce, callback))
        );
        proxy = createProxyWithNonce(
            _singleton,
            initializer,
            saltNonceWithCallback
        );
        if (address(callback) != address(0))
            callback.proxyCreated(proxy, _singleton, initializer, saltNonce);
    }

    /**
     * @notice Returns true if `account` is a contract.
     * @dev This function will return false if invoked during the constructor of a contract,
     *      as the code is not actually created until after the constructor finishes.
     * @param account The address being queried
     * @return True if `account` is a contract
     */
    function isContract(address account) internal view returns (bool) {
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @notice Returns the ID of the chain the contract is currently deployed on.
     * @return The ID of the current chain as a uint256.
     */
    function getChainId() public view returns (uint256) {
        uint256 id;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            id := chainid()
        }
        return id;
    }
}