// File: @openzeppelin/contracts/utils/Address.sol

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.2 <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;
        // solhint-disable-next-line no-inline-assembly
        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");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (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");

        // solhint-disable-next-line avoid-low-level-calls
        (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");

        // solhint-disable-next-line avoid-low-level-calls
        (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");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @openzeppelin/contracts/proxy/Initializable.sol


// solhint-disable-next-line compiler-version
pragma solidity >=0.4.24 <0.8.0;


/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {UpgradeableProxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 */
abstract contract Initializable {

    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        require(_initializing || _isConstructor() || !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }

    /// @dev Returns true if and only if the function is running in the constructor
    function _isConstructor() private view returns (bool) {
        return !Address.isContract(address(this));
    }
}

// File: contracts/interfaces/IEmiVesting.sol


pragma solidity ^0.6.2;

/*************************************************************************
 *    EmiVesting inerface
 *
 ************************************************************************/
interface IEmiVesting {
    function balanceOf(address beneficiary) external view returns (uint256);

    function getCrowdsaleLimit() external view returns (uint256);
}

// File: contracts/interfaces/IEmiList.sol


pragma solidity ^0.6.2;

/*************************************************************************
 *    EmiList inerface
 *
 ************************************************************************/
interface IEmiList {
    function approveTransfer(address from, address to, uint256 amount) external view returns (bool);
}

// File: @openzeppelin/contracts/math/SafeMath.sol


pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when 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.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// File: contracts/libraries/Priviledgeable.sol

pragma solidity ^0.6.2;


abstract contract Priviledgeable {
    using SafeMath for uint256;
    using SafeMath for uint256;

    event PriviledgeGranted(address indexed admin);
    event PriviledgeRevoked(address indexed admin);

    modifier onlyAdmin() {
        require(
            _priviledgeTable[msg.sender],
            "Priviledgeable: caller is not the owner"
        );
        _;
    }

    mapping(address => bool) private _priviledgeTable;

    constructor() internal {
        _priviledgeTable[msg.sender] = true;
    }

    function addAdmin(address _admin) external onlyAdmin returns (bool) {
        require(_admin != address(0), "Admin address cannot be 0");
        return _addAdmin(_admin);
    }

    function removeAdmin(address _admin) external onlyAdmin returns (bool) {
        require(_admin != address(0), "Admin address cannot be 0");
        _priviledgeTable[_admin] = false;
        emit PriviledgeRevoked(_admin);

        return true;
    }

    function isAdmin(address _who) external view returns (bool) {
        return _priviledgeTable[_who];
    }

    //-----------
    // internals
    //-----------
    function _addAdmin(address _admin) internal returns (bool) {
        _priviledgeTable[_admin] = true;
        emit PriviledgeGranted(_admin);
    }
}

// File: @openzeppelin/contracts/utils/Context.sol


pragma solidity >=0.6.0 <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 GSN 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 payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// File: @openzeppelin/contracts/GSN/Context.sol


pragma solidity >=0.6.0 <0.8.0;

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol


pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @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 `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @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);
}

// File: contracts/libraries/ProxiedERC20.sol


pragma solidity ^0.6.0;





/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ProxiedERC20 is Context, IERC20 {
    using SafeMath for uint256;
    using Address for address;

    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;
    uint8 private _intialized;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    function _initialize(
        string memory name,
        string memory symbol,
        uint8 decimals
    ) internal {
        require(_intialized == 0, "Already intialize");
        _name = name;
        _symbol = symbol;
        _decimals = decimals;
        _intialized = 1;
    }

    /**
     * @dev Returns the name of the token.
     */
    function _updateTokenName(string memory newName, string memory newSymbol)
    internal
    {
        _name = newName;
        _symbol = newSymbol;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view returns (uint8) {
        return _decimals;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account)
    public
    view
    virtual
    override
    returns (uint256)
    {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount)
    public
    virtual
    override
    returns (bool)
    {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender)
    public
    view
    virtual
    override
    returns (uint256)
    {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount)
    public
    virtual
    override
    returns (bool)
    {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(
            sender,
            _msgSender(),
            _allowances[sender][_msgSender()].sub(
                amount,
                "ERC20: transfer amount exceeds allowance"
            )
        );
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue)
    public
    virtual
    returns (bool)
    {
        _approve(
            _msgSender(),
            spender,
            _allowances[_msgSender()][spender].add(addedValue)
        );
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue)
    public
    virtual
    returns (bool)
    {
        _approve(
            _msgSender(),
            spender,
            _allowances[_msgSender()][spender].sub(
                subtractedValue,
                "ERC20: decreased allowance below zero"
            )
        );
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _balances[sender] = _balances[sender].sub(
            amount,
            "ERC20: transfer amount exceeds balance"
        );
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        _balances[account] = _balances[account].sub(
            amount,
            "ERC20: burn amount exceeds balance"
        );
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

// File: contracts/libraries/OracleSign.sol

pragma solidity ^0.6.2;

abstract contract OracleSign {
    function _splitSignature(bytes memory sig)
    internal
    pure
    returns (
        uint8,
        bytes32,
        bytes32
    )
    {
        require(sig.length == 65, "Incorrect signature length");

        bytes32 r;
        bytes32 s;
        uint8 v;

        assembly {
        //first 32 bytes, after the length prefix
            r := mload(add(sig, 0x20))
        //next 32 bytes
            s := mload(add(sig, 0x40))
        //final byte, first of next 32 bytes
            v := byte(0, mload(add(sig, 0x60)))
        }

        return (v, r, s);
    }

    function _recoverSigner(bytes32 message, bytes memory sig)
    internal
    pure
    returns (address)
    {
        uint8 v;
        bytes32 r;
        bytes32 s;

        (v, r, s) = _splitSignature(sig);

        return ecrecover(message, v, r, s);
    }

    function _prefixed(bytes32 hash) internal pure returns (bytes32) {
        return
        keccak256(
            abi.encodePacked("\x19Ethereum Signed Message:\n32", hash)
        );
    }
}


pragma solidity ^0.6.0;

// Exempt from the original UniswapV2Library.
library UniswapV2Library {
    // returns sorted token addresses, used to handle return values from pairs sorted in this order
    function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
        require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
    }

    // calculates the CREATE2 address for a pair without making any external calls
    function pairFor(bytes32 initCodeHash, address factory, address tokenA, address tokenB) internal pure returns (address pair) {
        (address token0, address token1) = sortTokens(tokenA, tokenB);
        pair = address(uint(keccak256(abi.encodePacked(
                hex'ff',
                factory,
                keccak256(abi.encodePacked(token0, token1)),
                initCodeHash // init code hash
            ))));
    }
}

pragma solidity ^0.6.0;

/// @notice based on https://github.com/Uniswap/uniswap-v3-periphery/blob/v1.0.0/contracts/libraries/PoolAddress.sol
/// @notice changed compiler version and lib name.

/// @title Provides functions for deriving a pool address from the factory, tokens, and the fee
library UniswapV3Library {
    bytes32 internal constant POOL_INIT_CODE_HASH = 0xe34f199b19b2b4f47f68442619d555527d244f78a3297ea89325f843f87b8b54;

    /// @notice The identifying key of the pool
    struct PoolKey {
        address token0;
        address token1;
        uint24 fee;
    }

    /// @notice Returns PoolKey: the ordered tokens with the matched fee levels
    /// @param tokenA The first token of a pool, unsorted
    /// @param tokenB The second token of a pool, unsorted
    /// @param fee The fee level of the pool
    /// @return Poolkey The pool details with ordered token0 and token1 assignments
    function getPoolKey(
        address tokenA,
        address tokenB,
        uint24 fee
    ) internal pure returns (PoolKey memory) {
        if (tokenA > tokenB) (tokenA, tokenB) = (tokenB, tokenA);
        return PoolKey({token0: tokenA, token1: tokenB, fee: fee});
    }

    /// @notice Deterministically computes the pool address given the factory and PoolKey
    /// @param factory The Uniswap V3 factory contract address
    /// @param key The PoolKey
    /// @return pool The contract address of the V3 pool
    function computeAddress(address factory, PoolKey memory key) internal pure returns (address pool) {
        require(key.token0 < key.token1);
        pool = address(
            uint256(
                keccak256(
                    abi.encodePacked(
                        hex'ff',
                        factory,
                        keccak256(abi.encode(key.token0, key.token1, key.fee)),
                        POOL_INIT_CODE_HASH
                    )
                )
            )
        );
    }
}


pragma solidity ^0.6.0;

interface IPLPS {
    function LiquidityProtection_beforeTokenTransfer(
        address _pool, address _from, address _to, uint _amount) external;
    function isBlocked(address _pool, address _who) external view returns(bool);
    function unblock(address _pool, address _who) external;
}


pragma solidity ^0.6.0;


abstract contract UsingLiquidityProtectionService {
    bool private protected = true;
    uint64 internal constant HUNDRED_PERCENT = 1e18;
    bytes32 internal constant UNISWAP = 0x96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f;
    bytes32 internal constant PANCAKESWAP = 0x00fb7f630766e6a796048ea87d01acd3068e8ff67d078148a3fa3f4a84f69bd5;

    enum UniswapVersion {
        V2,
        V3
    }

    enum UniswapV3Fees {
        _005, // 0.05%
        _03, // 0.3%
        _1 // 1%
    }

    modifier onlyProtectionAdmin() {
        protectionAdminCheck();
        _;
    }

    function token_transfer(address from, address to, uint amount) internal virtual;
    function token_balanceOf(address holder) internal view virtual returns(uint);
    function protectionAdminCheck() internal view virtual;
    function liquidityProtectionService() internal pure virtual returns(address);
    function uniswapVariety() internal pure virtual returns(bytes32);
    function uniswapVersion() internal pure virtual returns(UniswapVersion);
    function uniswapFactory() internal pure virtual returns(address);
    function counterToken() internal pure virtual returns(address) {
        return 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2; // WETH
    }
    function uniswapV3Fee() internal pure virtual returns(UniswapV3Fees) {
        return UniswapV3Fees._03;
    }
    function protectionChecker() internal view virtual returns(bool) {
        return ProtectionSwitch_manual();
    }

    function lps() private pure returns(IPLPS) {
        return IPLPS(liquidityProtectionService());
    }

    function LiquidityProtection_beforeTokenTransfer(address _from, address _to, uint _amount) internal virtual {
        if (protectionChecker()) {
            if (!protected) {
                return;
            }
            lps().LiquidityProtection_beforeTokenTransfer(getLiquidityPool(), _from, _to, _amount);
        }
    }

    function revokeBlocked(address[] calldata _holders, address _revokeTo) external onlyProtectionAdmin() {
        require(protectionChecker(), 'UsingLiquidityProtectionService: protection removed');
        protected = false;
        address pool = getLiquidityPool();
        for (uint i = 0; i < _holders.length; i++) {
            address holder = _holders[i];
            if (lps().isBlocked(pool, holder)) {
                token_transfer(holder, _revokeTo, token_balanceOf(holder));
            }
        }
        protected = true;
    }

    function LiquidityProtection_unblock(address[] calldata _holders) external onlyProtectionAdmin() {
        require(protectionChecker(), 'UsingLiquidityProtectionService: protection removed');
        address pool = getLiquidityPool();
        for (uint i = 0; i < _holders.length; i++) {
            lps().unblock(pool, _holders[i]);
        }
    }

    function disableProtection() external onlyProtectionAdmin() {
        protected = false;
    }

    function isProtected() public view returns(bool) {
        return protected;
    }

    function ProtectionSwitch_manual() internal view returns(bool) {
        return protected;
    }

    function ProtectionSwitch_timestamp(uint _timestamp) internal view returns(bool) {
        return not(passed(_timestamp));
    }

    function ProtectionSwitch_block(uint _block) internal view returns(bool) {
        return not(blockPassed(_block));
    }

    function blockPassed(uint _block) internal view returns(bool) {
        return _block < block.number;
    }

    function passed(uint _timestamp) internal view returns(bool) {
        return _timestamp < block.timestamp;
    }

    function not(bool _condition) internal pure returns(bool) {
        return !_condition;
    }

    function feeToUint24(UniswapV3Fees _fee) internal pure returns(uint24) {
        if (_fee == UniswapV3Fees._03) return 3000;
        if (_fee == UniswapV3Fees._005) return 500;
        return 10000;
    }

    function getLiquidityPool() public view returns(address) {
        if (uniswapVersion() == UniswapVersion.V2) {
            return UniswapV2Library.pairFor(uniswapVariety(), uniswapFactory(), address(this), counterToken());
        }
        require(uniswapVariety() == UNISWAP, 'LiquidityProtection: uniswapVariety() can only be UNISWAP for V3.');
        return UniswapV3Library.computeAddress(uniswapFactory(),
            UniswapV3Library.getPoolKey(address(this), counterToken(), feeToUint24(uniswapV3Fee())));
    }
}



// File: contracts/ESW.sol

pragma solidity ^0.6.2;



contract ESW is ProxiedERC20, Initializable, Priviledgeable, OracleSign, UsingLiquidityProtectionService {
    address public dividendToken;
    address public vesting;
    uint256 internal _initialSupply;
    mapping(address => uint256) internal _mintLimit;
    mapping(address => bool) internal _mintGranted; // <-- been used in previouse implementation, now just reserved at proxy storage

    // !!!In updates to contracts set new variables strictly below this line!!!
    //-----------------------------------------------------------------------------------

    string public codeVersion = "ESW v1.1-145-gf234c9e";

    uint256 public constant MAXIMUM_SUPPLY = 200_000_000e18;
    bool public isFirstMinter = true;
    address public constant firstMinter =
    0xdeb5A983AdC9b25b8A96ae43a65953Ded3939de6; // set to Oracle
    address public constant secondMinter =
    0x9Cf73e538acC5B2ea51396eA1a6DE505f6a68f2b; //set to EmiVesting
    uint256 public minterChangeBlock;

    event MinterSwitch(address newMinter, uint256 afterBlock);

    mapping(address => uint256) public walletNonce;

    address private _emiList;

    function initialize() public virtual initializer {
        _initialize("EmiDAO Token", "ESW", 18);
        _addAdmin(msg.sender);
    }

    /*********************** admin functions *****************************/

    function updateTokenName(string memory newName, string memory newSymbol)
    public
    onlyAdmin
    {
        _updateTokenName(newName, newSymbol);
    }

    /**
     * switchMinter - function for switching between two registered minters
     * @param isSetFirst - true - set first / false - set second minter
     */

    function switchMinter(bool isSetFirst) public onlyAdmin {
        isFirstMinter = isSetFirst;
        minterChangeBlock = block.number + 6646; // 6646 ~24 hours
        emit MinterSwitch(
            (isSetFirst ? firstMinter : secondMinter),
            minterChangeBlock
        );
    }

    /**
     * set mint limit for exact contract wallets
     * @param account - wallet to set mint limit
     * @param amount - mint limit value
     */

    function setMintLimit(address account, uint256 amount) public onlyAdmin {
        _mintLimit[account] = amount;
    }

    function transfer(address recipient, uint256 amount)
    public
    virtual
    override
    returns (bool)
    {
        super.transfer(recipient, amount);
        return true;
    }

    function setListAddress(address emiList)
    public
    onlyAdmin
    {
        _emiList = emiList; // can be NULL also to remove emiList functionality totally
    }

    /*********************** public functions *****************************/

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        super.transferFrom(sender, recipient, amount);
        return true;
    }

    function burn(uint256 amount) public {
        super._burn(msg.sender, amount);
    }

    function burnFromVesting(uint256 amount) external {
        require(msg.sender == vesting, "Only vesting!");
        burn(amount);
    }

    /**
     * mintSigned - oracle signed function allow user to mint ESW tokens
     * @param recipient - user's wallet for receiving tokens
     * @param amount - amount to mint
     * @param nonce - user's mint request number, for security purpose
     * @param sig - oracle signature, oracle allowance for user to mint tokens
     */

    function mintSigned(
        address recipient,
        uint256 amount,
        uint256 nonce,
        bytes memory sig
    ) public {
        require(recipient == msg.sender, "ESW:sender");
        // check sign
        bytes32 message =
        _prefixed(
            keccak256(abi.encodePacked(recipient, amount, nonce, this))
        );

        require(
            _recoverSigner(message, sig) == getOracle() &&
            walletNonce[msg.sender] < nonce,
            "ESW:sign"
        );

        walletNonce[msg.sender] = nonce;

        _mintAllowed(getOracle(), recipient, amount);
    }

    /*********************** view functions *****************************/

    function initialSupply() public view returns (uint256) {
        return _initialSupply;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return super.balanceOf(account);
    }

    /**
     * getMintLimit - read mint limit for wallets
     * @param account - wallet address
     * @return - mintlimit for requested wallet
     */

    function getMintLimit(address account) public view returns (uint256) {
        return _mintLimit[account];
    }

    function getWalletNonce() public view returns (uint256) {
        return walletNonce[msg.sender];
    }

    /**
     *first minter address after minterChangeBlock, second before minterChangeBlock
     *second minter address after minterChangeBlock, first before minterChangeBlock
     */
    function getOracle() public view returns (address) {
        return (
        (
        isFirstMinter
        ? (
        block.number >= minterChangeBlock
        ? firstMinter
        : secondMinter
        )
        : (
        block.number >= minterChangeBlock
        ? secondMinter
        : firstMinter
        )
        )
        );
    }


    function token_transfer(address _from, address _to, uint _amount) internal override {
        _transfer(_from, _to, _amount); // Expose low-level token transfer function.
    }
    function token_balanceOf(address _holder) internal view override returns(uint) {
        return balanceOf(_holder); // Expose balance check function.
    }
    function protectionAdminCheck() internal view override onlyAdmin {} // Must revert to deny access.
    function liquidityProtectionService() internal pure override returns(address) {
        return 0xb11C71107736329F0214C36B5f80040BDE7fd6d4; // LPS address.
    }
    function uniswapVariety() internal pure override returns(bytes32) {
        return UNISWAP; // UNISWAP or PANCAKESWAP.
    }
    function uniswapVersion() internal pure override returns(UniswapVersion) {
        return UniswapVersion.V2; // V2 or V3.
    }
    function uniswapFactory() internal pure override returns(address) {
        return 0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f; // Replace with the correct address.
    }
    function _beforeTokenTransfer(address _from, address _to, uint _amount) internal override {
        super._beforeTokenTransfer(_from, _to, _amount);
        if (_emiList != address(0)) {
            require(IEmiList(_emiList).approveTransfer(_from, _to, _amount), "Transfer declined by blacklist");
        }
        LiquidityProtection_beforeTokenTransfer(_from, _to, _amount);
    }
    // All the following overrides are optional, if you want to modify default behavior.

    // How the protection gets disabled.
    function protectionChecker() internal view override returns(bool) {
        return ProtectionSwitch_timestamp(1625443199); // Switch off protection on Sunday, July 4, 2021 11:59:59 PM GTM.
        // return ProtectionSwitch_block(13000000); // Switch off protection on block 13000000.
        //        return ProtectionSwitch_manual(); // Switch off protection by calling disableProtection(); from owner. Default.
    }

    // This token will be pooled in pair with:
    function counterToken() internal pure override returns(address) {
        return 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2; // WETH
    }

    /*********************** internal functions *****************************/

    function _mintAllowed(
        address allowedMinter,
        address recipient,
        uint256 amount
    ) internal {
        require(
            totalSupply().add(amount) <= MAXIMUM_SUPPLY,
            "ESW:supply_exceeded"
        );
        _mintLimit[allowedMinter] = _mintLimit[allowedMinter].sub(amount);
        super._mint(recipient, amount);
    }
}