// File: contracts/Presale.sol



pragma solidity ^0.8.9;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

import "./interfaces/IMintableERC20.sol";
import "./interfaces/IStaking.sol";
import "./interfaces/IUniswapRouterV2.sol";
import "./Initializable.sol";

contract Presale is Ownable, ReentrancyGuard, Initializable {

    event Mint (
        address indexed to,
        uint256 amount
    );

    struct PresaleRound {
        uint256 saleAmount;
        uint256 startTime;
        uint256 duration;
        uint256 price;
        uint256 minBuyPrice;
    }

    IMintableERC20 public token;
    IStaking public staking;
    IUniswapRouterV2 public uniswapRouter;

    uint256 public currentRoundId;
    uint256 public constant RELEASE_TOKEN_PRICE_X7 = 695860;
    bool public presaleStarted = false;
    address receiver;

    mapping(uint256 => PresaleRound) public rounds;
    mapping(uint256 => uint256) public tokensSold;
    uint256 public roundsLength;
    

    constructor() {
    }

    function init(address _token, address _staking, address _router, address _receiver) external onlyOwner notInitialized {
        token = IMintableERC20(_token);
        staking = IStaking(_staking);
        uniswapRouter = IUniswapRouterV2(_router);
        receiver = _receiver;

        initialized = true;
    }

    fallback() external {

    }

    function startPresale(PresaleRound[] memory _rounds) external onlyOwner {
        require(!presaleStarted, "Already started");

        uint256 _roundsLength = _rounds.length;

        for(uint256 i = 0; i < _roundsLength; i++) {
            rounds[i] = _rounds[i];
        }

        roundsLength = _roundsLength;
        presaleStarted = true;
    }

    function buy(uint256 _tokensToBuy) external payable nonReentrant {
        require(_tokensToBuy > 0, "ZeroTokensToBuy");

        uint256 _roundId = currentRoundId;
        PresaleRound memory round = rounds[_roundId];
        uint256 tokensInUse = tokensSold[_roundId];

        if(block.timestamp > round.startTime + round.duration && _roundId < roundsLength) {
            _roundId++;
            currentRoundId = _roundId;
            // rounds[_roundId + 1].startTime = block.timestamp;
            round = rounds[_roundId];
        }

        require(msg.value >= round.minBuyPrice, "Lower min buy price");
        require((msg.value * 1e18) >= (_tokensToBuy * round.price), "Not enought eth to pay");
        require((round.saleAmount - tokensInUse) >= _tokensToBuy, "Too much to buy");

        token.mint(address(this), _tokensToBuy);
        rounds[_roundId].saleAmount -= _tokensToBuy;
    
        staking.stakePresale(msg.sender, _tokensToBuy, msg.value);

        (bool success,) = payable(receiver).call{value: msg.value/2}("");
        require(success, "Payment not send");

        emit Mint(
            msg.sender,
            _tokensToBuy
        );
    }

    function releaseTokensToUniswap() external onlyOwner {
        uint256 ethBalance = address(this).balance;
        
        uint256 amountToMint = ethBalance * RELEASE_TOKEN_PRICE_X7 / 10000000;

        token.mint(address(this), amountToMint);
        token.approve(
            address(uniswapRouter),
            amountToMint
        );

        (uint256 amountInTokenAdded,,) = uniswapRouter.addLiquidityETH{value: ethBalance}(
            address(token),
            amountToMint,
            0,
            ethBalance,
            address(this),
            block.timestamp + 10 days
        );

        token.burn(amountToMint - amountInTokenAdded);
    }

    function getCurrentRoundInfo() external view returns(PresaleRound memory, uint256) {
        uint256 _roundId = currentRoundId;
        PresaleRound memory round = rounds[_roundId];

        if(block.timestamp > round.startTime + round.duration && _roundId < roundsLength) {
            _roundId++;
        }

        return (rounds[_roundId], tokensSold[_roundId]);
    }

    function changeReceiver(address _receiver) external onlyOwner {
        receiver = _receiver;
    }
}
// File: contracts/Initializable.sol



pragma solidity ^0.8.9;

abstract contract Initializable {
    bool public initialized;

    modifier notInitialized() {
        require(!initialized, "Already initialized");
        _;
    }
}
// File: contracts/interfaces/IMintableERC20.sol



pragma solidity ^0.8.9;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

interface IMintableERC20 is IERC20 {

    function mint(address _to, uint256 _amount) external;

    function burn(uint256 _amount) external;

}
// File: contracts/interfaces/IUniswapRouterV2.sol



pragma solidity ^0.8.9;

interface IUniswapRouterV2 {
     function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);

    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
}
// File: contracts/interfaces/IStaking.sol



pragma solidity ^0.8.9;

interface IStaking {

    function stakePresale(address _to, uint256 _amount, uint256 _ethDeposited) external;

}
// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @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);
    }
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @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);

    /**
     * @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 `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, 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 `from` to `to` 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 from,
        address to,
        uint256 amount
    ) external returns (bool);
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^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 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;
    }
}