// File: @tetu_io/tetu-contracts/contracts/base/UpgradeableProxy.sol



// SPDX-License-Identifier: ISC
/**
* By using this software, you understand, acknowledge and accept that Tetu
* and/or the underlying software are provided “as is” and “as available”
* basis and without warranties or representations of any kind either expressed
* or implied. Any use of this open source software released under the ISC
* Internet Systems Consortium license is done at your own risk to the fullest
* extent permissible pursuant to applicable law any and all liability as well
* as all warranties, including any fitness for a particular purpose with respect
* to Tetu and/or the underlying software and the use thereof are disclaimed.
*/

pragma solidity 0.8.4;

import "../openzeppelin/Proxy.sol";
import "../openzeppelin/Address.sol";


/// @title OpenZeppelin https://github.com/OpenZeppelin/openzeppelin-contracts/blob/release-v3.4/contracts/proxy/UpgradeableProxy.sol
/// @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.
///      Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
///      {TransparentUpgradeableProxy}.
abstract contract UpgradeableProxy is Proxy {

  /// @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 initializating the storage of the proxy like a Solidity constructor.
  constructor(address _logic) payable {
    assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
    _setImplementation(_logic);
  }

  /// @dev Emitted when the implementation is upgraded.
  event Upgraded(address indexed implementation);

  ///@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 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;

  /// @dev Returns the current implementation address.
  function _implementation() internal view virtual override returns (address impl) {
    bytes32 slot = _IMPLEMENTATION_SLOT;
    // solhint-disable-next-line no-inline-assembly
    assembly {
      impl := sload(slot)
    }
  }

  /// @dev Upgrades the proxy to a new implementation.
  ///      Emits an {Upgraded} event.
  function _upgradeTo(address newImplementation) internal virtual {
    _setImplementation(newImplementation);
    emit Upgraded(newImplementation);
  }

  /// @dev Stores a new address in the EIP1967 implementation slot.
  function _setImplementation(address newImplementation) private {
    require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");

    bytes32 slot = _IMPLEMENTATION_SLOT;

    // solhint-disable-next-line no-inline-assembly
    assembly {
      sstore(slot, newImplementation)
    }
  }
}

// File: @tetu_io/tetu-contracts/contracts/openzeppelin/Address.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @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
   * ====
   */
  function isContract(address account) internal view returns (bool) {
    // This method relies on extcodesize, which returns 0 for contracts in
    // construction, since the code is only stored at the end of the
    // constructor execution.

    uint256 size;
    assembly {
      size := extcodesize(account)
    }
    return size > 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://diligence.consensys.net/posts/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 functionCall(target, data, "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");
    require(isContract(target), "Address: call to non-contract");

    (bool success, bytes memory returndata) = target.call{value: value}(data);
    return verifyCallResult(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) {
    require(isContract(target), "Address: static call to non-contract");

    (bool success, bytes memory returndata) = target.staticcall(data);
    return verifyCallResult(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) {
    require(isContract(target), "Address: delegate call to non-contract");

    (bool success, bytes memory returndata) = target.delegatecall(data);
    return verifyCallResult(success, returndata, errorMessage);
  }

  /**
   * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
   * revert reason 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 {
      // 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

        assembly {
          let returndata_size := mload(returndata)
          revert(add(32, returndata), returndata_size)
        }
      } else {
        revert(errorMessage);
      }
    }
  }
}

// File: @tetu_io/tetu-contracts/contracts/openzeppelin/Proxy.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @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 internall call site, it will return directly to the external caller.
     */
  function _delegate(address implementation) internal virtual {
    // solhint-disable-next-line no-inline-assembly
    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 overriden 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 internall 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 overriden should call `super._beforeFallback()`.
     */
  function _beforeFallback() internal virtual {
  }
}

// File: contracts/interfaces/IControllable.sol



// SPDX-License-Identifier: ISC
/**
* By using this software, you understand, acknowledge and accept that Tetu
* and/or the underlying software are provided “as is” and “as available”
* basis and without warranties or representations of any kind either expressed
* or implied. Any use of this open source software released under the ISC
* Internet Systems Consortium license is done at your own risk to the fullest
* extent permissible pursuant to applicable law any and all liability as well
* as all warranties, including any fitness for a particular purpose with respect
* to Tetu and/or the underlying software and the use thereof are disclaimed.
*/

pragma solidity 0.8.4;

interface IControllable {

  function isController(address _contract) external view returns (bool);

  function isGovernance(address _contract) external view returns (bool);

}

// File: contracts/interfaces/IControllableExtended.sol



// SPDX-License-Identifier: ISC
/**
* By using this software, you understand, acknowledge and accept that Tetu
* and/or the underlying software are provided “as is” and “as available”
* basis and without warranties or representations of any kind either expressed
* or implied. Any use of this open source software released under the ISC
* Internet Systems Consortium license is done at your own risk to the fullest
* extent permissible pursuant to applicable law any and all liability as well
* as all warranties, including any fitness for a particular purpose with respect
* to Tetu and/or the underlying software and the use thereof are disclaimed.
*/

pragma solidity 0.8.4;

/// @dev This interface contains additional functions for Controllable class
///      Don't extend the exist Controllable for the reason of huge coherence
interface IControllableExtended {

  function created() external view returns (uint256 ts);

  function controller() external view returns (address adr);

}

// File: contracts/interfaces/ITetuProxy.sol



// SPDX-License-Identifier: ISC
/**
* By using this software, you understand, acknowledge and accept that Tetu
* and/or the underlying software are provided “as is” and “as available”
* basis and without warranties or representations of any kind either expressed
* or implied. Any use of this open source software released under the ISC
* Internet Systems Consortium license is done at your own risk to the fullest
* extent permissible pursuant to applicable law any and all liability as well
* as all warranties, including any fitness for a particular purpose with respect
* to Tetu and/or the underlying software and the use thereof are disclaimed.
*/

pragma solidity 0.8.4;

interface ITetuProxy {

  function upgrade(address _newImplementation) external;

  function implementation() external returns (address);

}

// File: contracts/TetuProxyGov.sol



// SPDX-License-Identifier: ISC
/**
* By using this software, you understand, acknowledge and accept that Tetu
* and/or the underlying software are provided “as is” and “as available”
* basis and without warranties or representations of any kind either expressed
* or implied. Any use of this open source software released under the ISC
* Internet Systems Consortium license is done at your own risk to the fullest
* extent permissible pursuant to applicable law any and all liability as well
* as all warranties, including any fitness for a particular purpose with respect
* to Tetu and/or the underlying software and the use thereof are disclaimed.
*/

pragma solidity 0.8.4;

import "./interfaces/IControllable.sol";
import "./interfaces/IControllableExtended.sol";
import "./interfaces/ITetuProxy.sol";
import "@tetu_io/tetu-contracts/contracts/base/UpgradeableProxy.sol";

/// @title EIP1967 Upgradable proxy implementation.
/// @dev Only Governance Wallet has access.
///      This Proxy should be used for non critical contracts only!
/// @author belbix
contract TetuProxyGov is UpgradeableProxy, ITetuProxy {

  constructor(address _logic) UpgradeableProxy(_logic) {
    //make sure that given logic is controllable and not inited
    require(IControllableExtended(_logic).created() == 0);
  }

  /// @notice Upgrade contract logic
  /// @dev Upgrade allowed only for Governance. No time-lock period
  /// @param _newImplementation Implementation address
  function upgrade(address _newImplementation) external override {
    require(IControllable(address(this)).isGovernance(msg.sender), "forbidden");
    _upgradeTo(_newImplementation);

    // the new contract must have the same ABI and you must have the power to change it again
    require(IControllable(address(this)).isGovernance(msg.sender), "wrong impl");
  }

  /// @notice Return current logic implementation
  function implementation() external override view returns (address) {
    return _implementation();
  }
}