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// This contract is part of Zellic’s smart contract dataset, which is a collection of publicly available contract code gathered as of March 2023.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.3;

/**

 * @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;
    }
}

/**

 * @dev Library for reading and writing primitive types to specific storage slots.

 *

 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.

 * This library helps with reading and writing to such slots without the need for inline assembly.

 *

 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.

 *

 * Example usage to set ERC1967 implementation slot:

 * ```

 * contract ERC1967 {

 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;

 *

 *     function _getImplementation() internal view returns (address) {

 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;

 *     }

 *

 *     function _setImplementation(address newImplementation) internal {

 *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");

 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;

 *     }

 * }

 * ```

 *

 * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._

 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }

    struct BooleanSlot {
        bool value;
    }

    struct Bytes32Slot {
        bytes32 value;
    }

    struct Uint256Slot {
        uint256 value;
    }

    /**

     * @dev Returns an `AddressSlot` with member `value` located at `slot`.

     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        /// @solidity memory-safe-assembly
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r.slot := slot
        }
    }

    /**

     * @dev Returns an `BooleanSlot` with member `value` located at `slot`.

     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        /// @solidity memory-safe-assembly
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r.slot := slot
        }
    }

    /**

     * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.

     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        /// @solidity memory-safe-assembly
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r.slot := slot
        }
    }

    /**

     * @dev Returns an `Uint256Slot` with member `value` located at `slot`.

     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        /// @solidity memory-safe-assembly
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r.slot := slot
        }
    }
}

/**

 * @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

     * ====

     *

     * [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/v0.5.11/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
            // solhint-disable-next-line no-inline-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

/**

 * @dev This abstract contract provides getters and event emitting update functions for

 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.

 *

 * _Available since v4.1._

 *

 * @custom:oz-upgrades-unsafe-allow delegatecall

 */
abstract contract ERC1967Upgrade {
    // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
    bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;

    /**

     * @dev Storage slot with the address of the current implementation.

     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is

     * validated in the constructor.

     */
    bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;

    /**

     * @dev Emitted when the implementation is upgraded.

     */
    event Upgraded(address indexed implementation);

    /**

     * @dev Returns the current implementation address.

     */
    function _getImplementation() internal view returns (address) {
        return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
    }

    /**

     * @dev Stores a new address in the EIP1967 implementation slot.

     */
    function _setImplementation(address newImplementation) private {
        require(Address.isContract(newImplementation), "ERC1967: Contract required");
        StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
    }

    /**

     * @dev Perform implementation upgrade

     *

     * Emits an {Upgraded} event.

     */
    function _upgradeTo(address newImplementation) internal {
        _setImplementation(newImplementation);
        emit Upgraded(newImplementation);
    }

    /**

     * @dev Perform implementation upgrade with additional setup call.

     *

     * Emits an {Upgraded} event.

     */
    function _upgradeToAndCall(

        address newImplementation,

        bytes memory data,

        bool forceCall

    ) internal {
        _upgradeTo(newImplementation);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(newImplementation, data);
        }
    }

    /**

     * @dev Storage slot with the admin of the contract.

     * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is

     * validated in the constructor.

     */
    bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;

    /**

     * @dev Emitted when the admin account has changed.

     */
    event AdminChanged(address previousAdmin, address newAdmin);

    /**

     * @dev Returns the current admin.

     */
    function _getAdmin() internal view returns (address) {
        return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
    }

    /**

     * @dev Stores a new address in the EIP1967 admin slot.

     */
    function _setAdmin(address newAdmin) private {
        require(newAdmin != address(0), "ERC1967: Zero address disallowed");
        StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
    }

    /**

     * @dev Changes the admin of the proxy.

     *

     * Emits an {AdminChanged} event.

     */
    function _changeAdmin(address newAdmin) internal {
        emit AdminChanged(_getAdmin(), newAdmin);
        _setAdmin(newAdmin);
    }
}

/**

 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM

 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to

 * be specified by overriding the virtual {_implementation} function.

 *

 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a

 * different contract through the {_delegate} function.

 *

 * The success and return data of the delegated call will be returned back to the caller of the proxy.

 */
abstract contract Proxy {
    /**

     * @dev Delegates the current call to `implementation`.

     *

     * This function does not return to its internal call site, it will return directly to the external caller.

     */
    function _delegate(address implementation) internal virtual {
        assembly {
            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())

            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)

            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())

            switch result
            // delegatecall returns 0 on error.
            case 0 {
                revert(0, returndatasize())
            }
            default {
                return(0, returndatasize())
            }
        }
    }

    /**

     * @dev This is a virtual function that should be overridden so it returns the address to which the fallback function

     * and {_fallback} should delegate.

     */
    function _implementation() internal view virtual returns (address);

    /**

     * @dev Delegates the current call to the address returned by `_implementation()`.

     *

     * This function does not return to its internal call site, it will return directly to the external caller.

     */
    function _fallback() internal virtual {
        _beforeFallback();
        _delegate(_implementation());
    }

    /**

     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other

     * function in the contract matches the call data.

     */
    fallback() external payable virtual {
        _fallback();
    }

    /**

     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data

     * is empty.

     */
    receive() external payable virtual {
        _fallback();
    }

    /**

     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`

     * call, or as part of the Solidity `fallback` or `receive` functions.

     *

     * If overridden should call `super._beforeFallback()`.

     */
    function _beforeFallback() internal virtual {}
}

/**

 * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an

 * implementation address that can be changed. This address is stored in storage in the location specified by

 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the

 * implementation behind the proxy.

 */
contract ERC1967Proxy is Proxy, ERC1967Upgrade {
    /**

     * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.

     *

     * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded

     * function call, and allows initializing the storage of the proxy like a Solidity constructor.

     */
    constructor(address _logic, bytes memory _data) payable {
        _upgradeToAndCall(_logic, _data, false);
    }

    /**

     * @dev Returns the current implementation address.

     */
    function _implementation() internal view virtual override returns (address impl) {
        return ERC1967Upgrade._getImplementation();
    }
}

/**

 * @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 anymore. Can only be called by the current owner.

     *

     * NOTE: Renouncing ownership will leave the contract without an owner,

     * thereby removing 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);
    }
}

/**

 * @dev This contract implements a proxy that is upgradeable by an admin.

 *

 * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector

 * clashing], which can potentially be used in an attack, this contract uses the

 * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two

 * things that go hand in hand:

 *

 * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if

 * that call matches one of the admin functions exposed by the proxy itself.

 * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the

 * implementation. If the admin tries to call a function on the implementation it will fail with an error that says

 * "admin cannot fallback to proxy target".

 *

 * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing

 * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due

 * to sudden errors when trying to call a function from the proxy implementation.

 *

 * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,

 * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.

 */
contract TransparentUpgradeableProxy is ERC1967Proxy {
    /**

     * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and

     * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.

     */
    constructor(
        address _logic,
        address admin_,
        bytes memory _data
    ) payable ERC1967Proxy(_logic, _data) {
        _changeAdmin(admin_);
    }

    /**

     * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.

     */
    modifier ifAdmin() {
        if (msg.sender == _getAdmin()) {
            _;
        } else {
            _fallback();
        }
    }

    /**

     * @dev Returns the current admin.

     *

     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.

     *

     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the

     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.

     * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`

     */
    function admin() external ifAdmin returns (address admin_) {
        admin_ = _getAdmin();
    }

    /**

     * @dev Returns the current implementation.

     *

     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.

     *

     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the

     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.

     * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`

     */
    function implementation() external ifAdmin returns (address implementation_) {
        implementation_ = _implementation();
    }

    /**

     * @dev Changes the admin of the proxy.

     *

     * Emits an {AdminChanged} event.

     *

     * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.

     */
    function changeAdmin(address newAdmin) external virtual ifAdmin {
        _changeAdmin(newAdmin);
    }

    /**

     * @dev Upgrade the implementation of the proxy.

     *

     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.

     */
    function upgradeTo(address newImplementation) external ifAdmin {
        _upgradeToAndCall(newImplementation, bytes(""), false);
    }

    /**

     * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified

     * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the

     * proxied contract.

     *

     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.

     */
    function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
        _upgradeToAndCall(newImplementation, data, true);
    }

    /**

     * @dev Returns the current admin.

     */
    function _admin() internal view virtual returns (address) {
        return _getAdmin();
    }

    /**

     * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.

     */
    function _beforeFallback() internal virtual override {
        require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
        super._beforeFallback();
    }
}

/**

 * @dev This is an auxiliary contract meant to be assigned as the admin of a {TransparentUpgradeableProxy}. For an

 * explanation of why you would want to use this see the documentation for {TransparentUpgradeableProxy}.

 */
contract ProxyAdmin is Ownable {
    /**

     * @dev Returns the current implementation of `proxy`.

     *

     * Requirements:

     *

     * - This contract must be the admin of `proxy`.

     */
    function getProxyImplementation(TransparentUpgradeableProxy proxy) public view virtual returns (address) {
        // We need to manually run the static call since the getter cannot be flagged as view
        // bytes4(keccak256("implementation()")) == 0x5c60da1b
        (bool success, bytes memory returndata) = address(proxy).staticcall(hex"5c60da1b");
        require(success);
        return abi.decode(returndata, (address));
    }

    /**

     * @dev Returns the current admin of `proxy`.

     *

     * Requirements:

     *

     * - This contract must be the admin of `proxy`.

     */
    function getProxyAdmin(TransparentUpgradeableProxy proxy) public view virtual returns (address) {
        // We need to manually run the static call since the getter cannot be flagged as view
        // bytes4(keccak256("admin()")) == 0xf851a440
        (bool success, bytes memory returndata) = address(proxy).staticcall(hex"f851a440");
        require(success);
        return abi.decode(returndata, (address));
    }

    /**

     * @dev Changes the admin of `proxy` to `newAdmin`.

     *

     * Requirements:

     *

     * - This contract must be the current admin of `proxy`.

     */
    function changeProxyAdmin(TransparentUpgradeableProxy proxy, address newAdmin) public virtual onlyOwner {
        proxy.changeAdmin(newAdmin);
    }

    /**

     * @dev Upgrades `proxy` to `implementation`. See {TransparentUpgradeableProxy-upgradeTo}.

     *

     * Requirements:

     *

     * - This contract must be the admin of `proxy`.

     */
    function upgrade(TransparentUpgradeableProxy proxy, address implementation) public virtual onlyOwner {
        proxy.upgradeTo(implementation);
    }

    /**

     * @dev Upgrades `proxy` to `implementation` and calls a function on the new implementation. See

     * {TransparentUpgradeableProxy-upgradeToAndCall}.

     *

     * Requirements:

     *

     * - This contract must be the admin of `proxy`.

     */
    function upgradeAndCall(

        TransparentUpgradeableProxy proxy,

        address implementation,

        bytes memory data

    ) public payable virtual onlyOwner {
        proxy.upgradeToAndCall{value: msg.value}(implementation, data);
    }
}

contract ProxyFactory is Ownable {
    event OnProxyDeployed (address adminAddress, address proxyAddress);

    function deploy (bytes32 adminSalt, bytes32 proxySalt, address implementationAddr, address proxyOwnerAddr, bytes memory initData) external onlyOwner {
        // Basic check of input parameters
        require(adminSalt != bytes32(0), "Admin salt required");
        require(proxySalt != bytes32(0), "Proxy salt required");
        require(implementationAddr != address(0) && implementationAddr != address(this), "Invalid logic address");

        // Get the predictable address of both the proxy and the proxy admin
        (address adminContractAddr, address proxyContractAddr) = getDeploymentAddress(adminSalt, proxySalt, implementationAddr, initData);

        // Make sure the contract addresses above were not taken
        require(adminContractAddr.code.length == 0, "Admin address already taken");
        require(proxyContractAddr.code.length == 0, "Proxy address already taken");

        // Deploy the proxy admin
        ProxyAdmin adminInstance = (new ProxyAdmin){salt: adminSalt}();
        require(address(adminInstance) == adminContractAddr, "Admin deploy failed");

        // Deploy the transparent proxy
        TransparentUpgradeableProxy proxy = (new TransparentUpgradeableProxy){salt: proxySalt}(implementationAddr, address(adminInstance), initData);
        require(address(proxy) == proxyContractAddr, "Proxy deploy failed");

        // Transfer ownership of the Proxy Admin
        adminInstance.transferOwnership(proxyOwnerAddr);

        emit OnProxyDeployed(address(adminInstance), address(proxy));
    }

    function getDeploymentAddress (bytes32 adminSalt, bytes32 proxySalt, address implementationAddr, bytes memory initData) public view returns (address adminContractAddr, address proxyContractAddr) {
        adminContractAddr = address(uint160(uint256(
                                keccak256(abi.encodePacked(bytes1(0xff), address(this), adminSalt, keccak256(type(ProxyAdmin).creationCode)))
                            )));

        proxyContractAddr = address(uint160(uint256(
                                keccak256(abi.encodePacked(bytes1(0xff), address(this), proxySalt, keccak256(
                                    abi.encodePacked(type(TransparentUpgradeableProxy).creationCode, abi.encode(implementationAddr, adminContractAddr, initData))
                                )))
                            )));
    }
}