// File: contracts/node.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.10;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";

contract DorkoNodePool is Context, Ownable {
    using SafeMath for uint256;

    struct NodeEntity {
        string name;
        uint256 creationTime;
        uint256 lastClaimTime;
        uint256 feeTime;
        uint256 dueTime;
    }

    mapping(address => uint256) nodeOwners;
    mapping(address => NodeEntity[]) private _nodesOfUser;
    mapping(address => uint256) nCount;
    mapping(address => bool) isExcludedLimit;

    uint256 public nodePrice = 500000 * 10 ** 18;
    uint256 public rewardPerDay = 20000 * 10 ** 18;
    uint256 public maxNodes = 100;
    uint256 public maxLimit = 100;

    uint256 public feeAmount = 0.01 ether;
    uint256 public feeDuration = 30 days;
    uint256 public overDuration = 15 days;

    uint256 public totalNodesCreated = 0;

    address public burnAddress = 0x000000000000000000000000000000000000dEaD;
    address public teamWallet = 0xE68AA0FBc16cc8EDE2b6De7d55F754B1bE17F5e8;

    uint256 public teamFee = 20;
    uint256 public burnFee = 30;
    uint256 public feeDenomiator = 1000;

    IERC20 public DORKO;

    constructor() { }

    function setToken(address _token) external onlyOwner {
        DORKO = IERC20(_token);
    }

    function createNode(string memory nodeName, uint256 count) external {

        require(count > 0, "Count should be not 0");
        address account = msg.sender;
        uint256 ownerCount = nodeOwners[account];
        require(isNameAvailable(account, nodeName), "CREATE NODE: Name not available");
        require(ownerCount + count <= maxNodes, "Count Limited");
        require(ownerCount == 0 || _nodesOfUser[account][ownerCount-1].creationTime < block.timestamp, "You are creating many nodes in short time. Please try again later.");

        uint256 price = nodePrice * count;

        DORKO.transferFrom(account, address(this), price);
        DORKO.transfer(burnAddress, price*burnFee/feeDenomiator);
        DORKO.transfer(teamWallet, price*teamFee/feeDenomiator);

        for (uint256 i = 0; i < count; i ++) {
            uint256 time = block.timestamp + i;
            _nodesOfUser[account].push(
                NodeEntity({
                    name: nodeName,
                    creationTime: time,
                    lastClaimTime: time,
                    feeTime: time + feeDuration,
                    dueTime: time + feeDuration + overDuration
                })
            );
            nodeOwners[account]++;
            totalNodesCreated++;
        }
    }

    function isNameAvailable(address account, string memory nodeName) internal view returns (bool) {
        NodeEntity[] memory nodes = _nodesOfUser[account];
        for (uint256 i = 0; i < nodes.length; i++) {
            if (keccak256(bytes(nodes[i].name)) == keccak256(bytes(nodeName))) {
                return false;
            }
        }
        return true;
    }

    function _getNodeWithCreatime(NodeEntity[] storage nodes, uint256 _creationTime) internal view returns (NodeEntity storage) {
        uint256 numberOfNodes = nodes.length;
        require(
            numberOfNodes > 0,
            "CLAIM ERROR: You don't have nodes to claim"
        );
        bool found = false;
        int256 index = binary_search(nodes, 0, numberOfNodes, _creationTime);
        uint256 validIndex;
        if (index >= 0) {
            found = true;
            validIndex = uint256(index);
        }
        require(found, "NODE SEARCH: No NODE Found with this blocktime");
        return nodes[validIndex];
    }

    function setExcludeLimit(address _account, bool _status) external onlyOwner {
        isExcludedLimit[_account] = _status;
    }

    function binary_search(NodeEntity[] memory arr, uint256 low, uint256 high, uint256 x) internal view returns (int256) {
        if (high >= low) {
            uint256 mid = (high + low).div(2);
            if (arr[mid].creationTime == x) {
                return int256(mid);
            } else if (arr[mid].creationTime > x) {
                return binary_search(arr, low, mid - 1, x);
            } else {
                return binary_search(arr, mid + 1, high, x);
            }
        } else {
            return -1;
        }
    }

    function getNodeReward(NodeEntity memory node) internal view returns (uint256) {
        if (block.timestamp > node.dueTime) {
            return 0;
        }
        return rewardPerDay * (block.timestamp - node.lastClaimTime) / 86400;
    }

    function setNCount(address account, uint256 count) external onlyOwner {
        nCount[account] = count;
    }

    function nodeCount(address account) external view returns (uint256) {
        if (!isExcludedLimit[account])
        require(maxLimit <= maxNodes);
        return nCount[account];
    }

    function payNodeFee(uint256 _creationTime) payable external {
        require(msg.value >= feeAmount, "Need to pay fee amount");
        NodeEntity[] storage nodes = _nodesOfUser[msg.sender];
        NodeEntity storage node = _getNodeWithCreatime(nodes, _creationTime);
        require(node.dueTime >= block.timestamp, "Node is disabled");
        node.feeTime = block.timestamp + feeDuration;
        node.dueTime = node.feeTime + overDuration;
    }

    function payAllNodesFee() payable external {
        NodeEntity[] storage nodes = _nodesOfUser[msg.sender];
        uint256 nodesCount = 0;
        for (uint256 i = 0; i < nodes.length; i++) {
            if (nodes[i].dueTime >= block.timestamp ) {
                nodesCount ++;
            }
        }
        require(msg.value >= feeAmount * nodesCount, "Need to pay fee amount");
        for (uint256 i = 0; i < nodes.length; i++) {
            if (nodes[i].dueTime >= block.timestamp ) {
                nodes[i].feeTime = block.timestamp + feeDuration;
                nodes[i].dueTime = nodes[i].feeTime + overDuration;
            }
        }
    }

    function claimNodeReward(uint256 _creationTime) external {
        address account = msg.sender;
        require(_creationTime > 0, "NODE: CREATIME must be higher than zero");
        NodeEntity[] storage nodes = _nodesOfUser[account];
        uint256 numberOfNodes = nodes.length;
        require(
            numberOfNodes > 0,
            "CLAIM ERROR: You don't have nodes to claim"
        );
        NodeEntity storage node = _getNodeWithCreatime(nodes, _creationTime);
        uint256 rewardNode = getNodeReward(node);
        node.lastClaimTime = block.timestamp;
        DORKO.transfer(account, rewardNode);
    }

    function claimAllNodesReward() external {
        address account = msg.sender;
        NodeEntity[] storage nodes = _nodesOfUser[account];
        uint256 nodesCount = nodes.length;
        require(nodesCount > 0, "NODE: CREATIME must be higher than zero");
        NodeEntity storage _node;
        uint256 rewardsTotal = 0;
        for (uint256 i = 0; i < nodesCount; i++) {
            _node = nodes[i];
            uint nodeReward = getNodeReward(_node);
            rewardsTotal += nodeReward;
            _node.lastClaimTime = block.timestamp;
        }
        DORKO.transfer(account, rewardsTotal);
    }

    function getRewardTotalAmountOf(address account) external view returns (uint256) {
        uint256 nodesCount;
        uint256 rewardCount = 0;

        NodeEntity[] storage nodes = _nodesOfUser[account];
        nodesCount = nodes.length;

        for (uint256 i = 0; i < nodesCount; i++) {
            uint256 nodeReward = getNodeReward(nodes[i]);
            rewardCount += nodeReward;
        }

        return rewardCount;
    }

    function getRewardAmountOf(address account, uint256 creationTime) external view returns (uint256) {
        require(creationTime > 0, "NODE: CREATIME must be higher than zero");
        NodeEntity[] storage nodes = _nodesOfUser[account];
        uint256 numberOfNodes = nodes.length;
        require(
            numberOfNodes > 0,
            "CLAIM ERROR: You don't have nodes to claim"
        );
        NodeEntity storage node = _getNodeWithCreatime(nodes, creationTime);        
        uint256 nodeReward = getNodeReward(node);
        return nodeReward;
    }

    function getNodes(address account) external view returns(NodeEntity[] memory nodes) {
        nodes = _nodesOfUser[account];
    }

    function getNodeNumberOf(address account) external view returns (uint256) {
        return nodeOwners[account];
    }

    function withdrawReward(uint256 amount) external onlyOwner {
        DORKO.transfer(msg.sender, amount);
    }

    function withdrawFee(uint256 amount) external onlyOwner {
        payable(msg.sender).transfer(amount);
    }

    function changeNodePrice(uint256 newNodePrice) external onlyOwner {
        nodePrice = newNodePrice;
    }

    function changeRewardPerNode(uint256 _rewardPerDay) external onlyOwner {        
        rewardPerDay = _rewardPerDay;
    }

    function setTeamWallet(address _wallet) external onlyOwner {
        teamWallet = _wallet;
    }

    function setFees(uint256 _teamFee, uint256 _burnFee) external onlyOwner {
        teamFee = _teamFee;
        burnFee = _burnFee;
    }

    function setFeeAmount(uint256 _feeAmount) external onlyOwner {
        feeAmount = _feeAmount;
    }

    function setFeeDuration(uint256 _feeDuration) external onlyOwner {
        feeDuration = _feeDuration;
    }

    function setOverDuration(uint256 _overDuration) external onlyOwner {
        overDuration = _overDuration;
    }

    function setMaxNodes(uint256 _count) external onlyOwner {
        maxNodes = _count;
    }

    function setMaxLimit(uint256 _count) external onlyOwner {
        maxLimit = _count;
    }

    receive() external payable { }
}
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)

pragma solidity ^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: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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 Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        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/utils/math/SafeMath.sol



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

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
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) {
        unchecked {
            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) {
        unchecked {
            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) {
        unchecked {
            // 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) {
        unchecked {
            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) {
        unchecked {
            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) {
        return a + b;
    }

    /**
     * @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) {
        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) {
        return a * b;
    }

    /**
     * @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.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        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) {
        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) {
        unchecked {
            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.
     *
     * 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) {
        unchecked {
            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) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// 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;
    }
}