pragma solidity ^0.5.0;


interface IERC20 {
    
    function totalSupply() external view returns (uint256);

    
    function balanceOf(address account) external view returns (uint256);

    
    function transfer(address recipient, uint256 amount) external returns (bool);

    
    function allowance(address owner, address spender) external view returns (uint256);

    
    function approve(address spender, uint256 amount) external returns (bool);

    
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    
    event Transfer(address indexed from, address indexed to, uint256 value);

    
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

library SafeMath {
    
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        uint256 c = a - b;

        return c;
    }

    
    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;
    }

    
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        
        require(b > 0, "SafeMath: division by zero");
        uint256 c = a / b;
        

        return c;
    }

    
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0, "SafeMath: modulo by zero");
        return a % b;
    }
}

library Address {
    
    function isContract(address account) internal view returns (bool) {
        
        
        

        uint256 size;
        
        assembly { size := extcodesize(account) }
        return size > 0;
    }
}

library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        
        
        
        
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value);
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    
    function callOptionalReturn(IERC20 token, bytes memory data) private {
        
        

        
        
        
        
        
        require(address(token).isContract(), "SafeERC20: call to non-contract");

        
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success, "SafeERC20: low-level call failed");

        if (returndata.length > 0) { 
            
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

contract ReentrancyGuard {
    
    uint256 private _guardCounter;

    constructor () internal {
        
        
        _guardCounter = 1;
    }

    
    modifier nonReentrant() {
        _guardCounter += 1;
        uint256 localCounter = _guardCounter;
        _;
        require(localCounter == _guardCounter, "ReentrancyGuard: reentrant call");
    }
}

contract Crowdsale is ReentrancyGuard {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    
    IERC20 private _token;

    
    address payable private _wallet;

    
    
    
    
    uint256 private _rate;

    
    uint256 private _weiRaised;

    
    event TokensPurchased(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);

    
    constructor (uint256 rate, address payable wallet, IERC20 token) public {
        require(rate > 0, "Crowdsale: rate is 0");
        require(wallet != address(0), "Crowdsale: wallet is the zero address");
        require(address(token) != address(0), "Crowdsale: token is the zero address");

        _rate = rate;
        _wallet = wallet;
        _token = token;
    }

    
    function () external payable {
        buyTokens(msg.sender);
    }

    
    function token() public view returns (IERC20) {
        return _token;
    }

    
    function wallet() public view returns (address payable) {
        return _wallet;
    }

    
    function rate() public view returns (uint256) {
        return _rate;
    }

    
    function weiRaised() public view returns (uint256) {
        return _weiRaised;
    }

    
    function buyTokens(address beneficiary) public nonReentrant payable {
        uint256 weiAmount = msg.value;
        _preValidatePurchase(beneficiary, weiAmount);

        
        uint256 tokens = _getTokenAmount(weiAmount);

        
        _weiRaised = _weiRaised.add(weiAmount);

        _processPurchase(beneficiary, tokens);
        emit TokensPurchased(msg.sender, beneficiary, weiAmount, tokens);

        _updatePurchasingState(beneficiary, weiAmount);

        _forwardFunds();
        _postValidatePurchase(beneficiary, weiAmount);
    }

    
    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
        require(beneficiary != address(0), "Crowdsale: beneficiary is the zero address");
        require(weiAmount != 0, "Crowdsale: weiAmount is 0");
    }

    
    function _postValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
        
    }

    
    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
        _token.safeTransfer(beneficiary, tokenAmount);
    }

    
    function _processPurchase(address beneficiary, uint256 tokenAmount) internal {
        _deliverTokens(beneficiary, tokenAmount);
    }

    
    function _updatePurchasingState(address beneficiary, uint256 weiAmount) internal {
        
    }

    
    function _getTokenAmount(uint256 weiAmount) internal view returns (uint256) {
        return weiAmount.mul(_rate);
    }

    
    function _forwardFunds() internal {
        _wallet.transfer(msg.value);
    }
}

contract ERC20 is IERC20 {
    using SafeMath for uint256;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }

    
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }

    
    function transfer(address recipient, uint256 amount) public returns (bool) {
        _transfer(msg.sender, recipient, amount);
        return true;
    }

    
    function allowance(address owner, address spender) public view returns (uint256) {
        return _allowances[owner][spender];
    }

    
    function approve(address spender, uint256 value) public returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }

    
    function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
        return true;
    }

    
    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        _approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
        return true;
    }

    
    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        _approve(msg.sender, spender, _allowances[msg.sender][spender].sub(subtractedValue));
        return true;
    }

    
    function _transfer(address sender, address recipient, uint256 amount) internal {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _balances[sender] = _balances[sender].sub(amount);
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    
    function _mint(address account, uint256 amount) internal {
        require(account != address(0), "ERC20: mint to the zero address");

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

     
    function _burn(address account, uint256 value) internal {
        require(account != address(0), "ERC20: burn from the zero address");

        _totalSupply = _totalSupply.sub(value);
        _balances[account] = _balances[account].sub(value);
        emit Transfer(account, address(0), value);
    }

    
    function _approve(address owner, address spender, uint256 value) internal {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = value;
        emit Approval(owner, spender, value);
    }

    
    function _burnFrom(address account, uint256 amount) internal {
        _burn(account, amount);
        _approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
    }
}

library Roles {
    struct Role {
        mapping (address => bool) bearer;
    }

    
    function add(Role storage role, address account) internal {
        require(!has(role, account), "Roles: account already has role");
        role.bearer[account] = true;
    }

    
    function remove(Role storage role, address account) internal {
        require(has(role, account), "Roles: account does not have role");
        role.bearer[account] = false;
    }

    
    function has(Role storage role, address account) internal view returns (bool) {
        require(account != address(0), "Roles: account is the zero address");
        return role.bearer[account];
    }
}

contract MinterRole {
    using Roles for Roles.Role;

    event MinterAdded(address indexed account);
    event MinterRemoved(address indexed account);

    Roles.Role private _minters;

    constructor () internal {
        _addMinter(msg.sender);
    }

    modifier onlyMinter() {
        require(isMinter(msg.sender), "MinterRole: caller does not have the Minter role");
        _;
    }

    function isMinter(address account) public view returns (bool) {
        return _minters.has(account);
    }

    function addMinter(address account) public onlyMinter {
        _addMinter(account);
    }

    function renounceMinter() public {
        _removeMinter(msg.sender);
    }

    function _addMinter(address account) internal {
        _minters.add(account);
        emit MinterAdded(account);
    }

    function _removeMinter(address account) internal {
        _minters.remove(account);
        emit MinterRemoved(account);
    }
}

contract ERC20Mintable is ERC20, MinterRole {
    
    function mint(address account, uint256 amount) public onlyMinter returns (bool) {
        _mint(account, amount);
        return true;
    }
}

contract MintedCrowdsale is Crowdsale {
    
    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
        
        require(
            ERC20Mintable(address(token())).mint(beneficiary, tokenAmount),
                "MintedCrowdsale: minting failed"
        );
    }
}

contract TimedCrowdsale is Crowdsale {
    using SafeMath for uint256;

    uint256 private _openingTime;
    uint256 private _closingTime;

    
    event TimedCrowdsaleExtended(uint256 prevClosingTime, uint256 newClosingTime);

    
    modifier onlyWhileOpen {
        require(isOpen(), "TimedCrowdsale: not open");
        _;
    }

    
    constructor (uint256 openingTime, uint256 closingTime) public {
        
        require(openingTime >= block.timestamp, "TimedCrowdsale: opening time is before current time");
        
        require(closingTime > openingTime, "TimedCrowdsale: opening time is not before closing time");

        _openingTime = openingTime;
        _closingTime = closingTime;
    }

    
    function openingTime() public view returns (uint256) {
        return _openingTime;
    }

    
    function closingTime() public view returns (uint256) {
        return _closingTime;
    }

    
    function isOpen() public view returns (bool) {
        
        return block.timestamp >= _openingTime && block.timestamp <= _closingTime;
    }

    
    function hasClosed() public view returns (bool) {
        
        return block.timestamp > _closingTime;
    }

    
    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal onlyWhileOpen view {
        super._preValidatePurchase(beneficiary, weiAmount);
    }

    
    function _extendTime(uint256 newClosingTime) internal {
        require(!hasClosed(), "TimedCrowdsale: already closed");
        
        require(newClosingTime > _closingTime, "TimedCrowdsale: new closing time is before current closing time");

        emit TimedCrowdsaleExtended(_closingTime, newClosingTime);
        _closingTime = newClosingTime;
    }
}

contract Ownable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    
    constructor () internal {
        _owner = msg.sender;
        emit OwnershipTransferred(address(0), _owner);
    }

    
    function owner() public view returns (address) {
        return _owner;
    }

    
    modifier onlyOwner() {
        require(isOwner(), "Ownable: caller is not the owner");
        _;
    }

    
    function isOwner() public view returns (bool) {
        return msg.sender == _owner;
    }

    
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

contract AdminRole {
    using Roles for Roles.Role;

    event AdminAdded(address indexed account);
    event AdminRemoved(address indexed account);

    Roles.Role private _Admins;

    constructor () internal {
        _addAdmin(_msgSender());
    }

    modifier onlyAdmin() {
        require(isAdmin(_msgSender()), "AdminRole: caller does not have the Admin role");
        _;
    }

    function isAdmin(address account) public view returns (bool) {
        return _Admins.has(account);
    }

    function addAdmin(address account) public onlyAdmin {
        _addAdmin(account);
    }

    function renounceAdmin() public {
        _removeAdmin(_msgSender());
    }

    function _addAdmin(address account) internal {
        _Admins.add(account);
        emit AdminAdded(account);
    }

    function _removeAdmin(address account) internal {
        _Admins.remove(account);
        emit AdminRemoved(account);
    }

    function _msgSender() internal view returns (address) {
        return msg.sender;
    }
}

contract ManingiMinesCrowdsale is
  Crowdsale,
  MintedCrowdsale,
  TimedCrowdsale,
  AdminRole
{
  
  
  
  
  uint256 private _rate;

  event RateChanged(uint256 oldRate, uint256 newRate);

  constructor (
    uint256 rate, address payable wallet, IERC20 token,
    uint256 openingTime, uint256 closingTime
  )
    Crowdsale(rate, wallet, token)
    TimedCrowdsale(openingTime, closingTime) public
  {
    _rate = rate;
  }

  
  function rate() public view returns (uint256) {
      return _rate;
  }

  
  function setRate(uint256 newRate) onlyAdmin public {
    uint256 oldRate = _rate;
    _rate = newRate;
    emit RateChanged(oldRate, newRate);
  }

  
  function extendClosingTime(uint256 newClosingTime) onlyAdmin public {
    _extendTime(newClosingTime);
  }

  
  function _getTokenAmount(uint256 weiAmount) internal view returns (uint256) {
      return weiAmount.mul(_rate);
  }
}