Contract Source Code:

// SPDX-License-Identifier: MIT
pragma solidity 0.6.12;

import "../lib/openzeppelin/contracts/3.4.1/token/ERC20/IERC20.sol";
import "./lib/SafeMath.sol";
import "./interfaces/StrongPoolInterface.sol";
import "./interfaces/INodePackV3.sol";
import "./interfaces/IERC1155Preset.sol";
import "./interfaces/StrongNFTBonusInterface.sol";
import "./lib/rewards.sol";

contract ServiceV20 {
  event Requested(address indexed miner);
  event Claimed(address indexed miner, uint256 reward);

  using SafeMath for uint256;
  bool public initDone;
  address public admin;
  address public pendingAdmin;
  address public superAdmin;
  address public pendingSuperAdmin;
  address public serviceAdmin;
  address public parameterAdmin;
  address payable public feeCollector;

  IERC20 public strongToken;
  StrongPoolInterface public strongPool;

  uint256 public rewardPerBlockNumerator;
  uint256 public rewardPerBlockDenominator;

  uint256 public naasRewardPerBlockNumerator;
  uint256 public naasRewardPerBlockDenominator;

  uint256 public claimingFeeNumerator;
  uint256 public claimingFeeDenominator;

  uint256 public requestingFeeInWei;

  uint256 public strongFeeInWei;

  uint256 public recurringFeeInWei;
  uint256 public recurringNaaSFeeInWei;
  uint256 public recurringPaymentCycleInBlocks;

  uint256 public rewardBalance;

  mapping(address => uint256) public entityBlockLastClaimedOn;

  address[] public entities;
  mapping(address => uint256) public entityIndex;
  mapping(address => bool) public entityActive;
  mapping(address => bool) public requestPending;
  mapping(address => bool) public entityIsNaaS;
  mapping(address => uint256) public paidOnBlock;
  uint256 public activeEntities;

  string public desciption;

  uint256 public claimingFeeInWei;

  uint256 public naasRequestingFeeInWei;

  uint256 public naasStrongFeeInWei;

  bool public removedTokens;

  mapping(address => uint256) public traunch;

  uint256 public currentTraunch;

  mapping(bytes => bool) public entityNodeIsActive;
  mapping(bytes => bool) public entityNodeIsBYON;
  mapping(bytes => uint256) public entityNodeTraunch;
  mapping(bytes => uint256) public entityNodePaidOnBlock;
  mapping(bytes => uint256) public entityNodeClaimedOnBlock;
  mapping(address => uint128) public entityNodeCount;

  event Paid(address indexed entity, uint128 nodeId, bool isBYON, bool isRenewal, uint256 upToBlockNumber);
  event Migrated(address indexed from, address indexed to, uint128 fromNodeId, uint128 toNodeId, bool isBYON);

  uint256 public rewardPerBlockNumeratorNew;
  uint256 public rewardPerBlockDenominatorNew;
  uint256 public naasRewardPerBlockNumeratorNew;
  uint256 public naasRewardPerBlockDenominatorNew;
  uint256 public rewardPerBlockNewEffectiveBlock;

  StrongNFTBonusInterface public strongNFTBonus;

  uint256 public gracePeriodInBlocks;

  uint128 public maxNodes;
  uint256 public maxPaymentPeriods;

  event Deactivated(address indexed entity, uint128 nodeId, bool isBYON, uint256 atBlockNumber);
  event MigratedToNodePack(address indexed entity, uint128 fromNodeId, uint toPackId);

  uint256 public secondsPerBlock;
  uint256 public nodeLifetimeReward;
  mapping(bytes => uint256) public entityNodeClaimedTotal;
  mapping(address => uint128) public entityNodeDeactivatedCount;

  function init(
    address strongTokenAddress,
    address strongPoolAddress,
    address adminAddress,
    address superAdminAddress,
    uint256 rewardPerBlockNumeratorValue,
    uint256 rewardPerBlockDenominatorValue,
    uint256 naasRewardPerBlockNumeratorValue,
    uint256 naasRewardPerBlockDenominatorValue,
    uint256 requestingFeeInWeiValue,
    uint256 strongFeeInWeiValue,
    uint256 recurringFeeInWeiValue,
    uint256 recurringNaaSFeeInWeiValue,
    uint256 recurringPaymentCycleInBlocksValue,
    uint256 claimingFeeNumeratorValue,
    uint256 claimingFeeDenominatorValue,
    string memory desc
  ) external {
    require(!initDone, "init done");
    strongToken = IERC20(strongTokenAddress);
    strongPool = StrongPoolInterface(strongPoolAddress);
    admin = adminAddress;
    superAdmin = superAdminAddress;
    rewardPerBlockNumerator = rewardPerBlockNumeratorValue;
    rewardPerBlockDenominator = rewardPerBlockDenominatorValue;
    naasRewardPerBlockNumerator = naasRewardPerBlockNumeratorValue;
    naasRewardPerBlockDenominator = naasRewardPerBlockDenominatorValue;
    requestingFeeInWei = requestingFeeInWeiValue;
    strongFeeInWei = strongFeeInWeiValue;
    recurringFeeInWei = recurringFeeInWeiValue;
    recurringNaaSFeeInWei = recurringNaaSFeeInWeiValue;
    claimingFeeNumerator = claimingFeeNumeratorValue;
    claimingFeeDenominator = claimingFeeDenominatorValue;
    recurringPaymentCycleInBlocks = recurringPaymentCycleInBlocksValue;
    desciption = desc;
    initDone = true;
  }

  function updateServiceAdmin(address newServiceAdmin) external {
    require(msg.sender == superAdmin);
    serviceAdmin = newServiceAdmin;
  }

  function updateParameterAdmin(address newParameterAdmin) external {
    require(newParameterAdmin != address(0));
    require(msg.sender == superAdmin);
    parameterAdmin = newParameterAdmin;
  }

  function updateFeeCollector(address payable newFeeCollector) external {
    require(newFeeCollector != address(0));
    require(msg.sender == superAdmin);
    feeCollector = newFeeCollector;
  }

  function setPendingAdmin(address newPendingAdmin) external {
    require(msg.sender == admin);
    pendingAdmin = newPendingAdmin;
  }

  function acceptAdmin() external {
    require(msg.sender == pendingAdmin && msg.sender != address(0), "not pendingAdmin");
    admin = pendingAdmin;
    pendingAdmin = address(0);
  }

  function setPendingSuperAdmin(address newPendingSuperAdmin) external {
    require(msg.sender == superAdmin, "not superAdmin");
    pendingSuperAdmin = newPendingSuperAdmin;
  }

  function acceptSuperAdmin() external {
    require(msg.sender == pendingSuperAdmin && msg.sender != address(0), "not pendingSuperAdmin");
    superAdmin = pendingSuperAdmin;
    pendingSuperAdmin = address(0);
  }

  function isEntityActive(address entity) external view returns (bool) {
    return entityActive[entity] || (doesNodeExist(entity, 1) && !hasNodeExpired(entity, 1));
  }

  function updateRewardPerBlock(uint256 numerator, uint256 denominator) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    require(denominator != 0);
    rewardPerBlockNumerator = numerator;
    rewardPerBlockDenominator = denominator;
  }

  function updateNaaSRewardPerBlock(uint256 numerator, uint256 denominator) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    require(denominator != 0);
    naasRewardPerBlockNumerator = numerator;
    naasRewardPerBlockDenominator = denominator;
  }

  function updateRewardPerBlockNew(
    uint256 numerator,
    uint256 denominator,
    uint256 numeratorNass,
    uint256 denominatorNass,
    uint256 effectiveBlock
  ) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);

    rewardPerBlockNumeratorNew = numerator;
    rewardPerBlockDenominatorNew = denominator;
    naasRewardPerBlockNumeratorNew = numeratorNass;
    naasRewardPerBlockDenominatorNew = denominatorNass;
    rewardPerBlockNewEffectiveBlock = effectiveBlock != 0 ? effectiveBlock : block.number;
  }

  function deposit(uint256 amount) external {
    require(msg.sender == superAdmin);
    require(amount > 0);
    rewardBalance = rewardBalance.add(amount);
    require(strongToken.transferFrom(msg.sender, address(this), amount), "transfer failed");
  }

  function withdraw(address destination, uint256 amount) external {
    require(msg.sender == superAdmin);
    require(amount > 0);
    require(rewardBalance >= amount, "not enough");
    rewardBalance = rewardBalance.sub(amount);
    require(strongToken.transfer(destination, amount), "transfer failed");
  }

  function updateRequestingFee(uint256 feeInWei) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    requestingFeeInWei = feeInWei;
  }

  function updateStrongFee(uint256 feeInWei) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    strongFeeInWei = feeInWei;
  }

  function updateNaasRequestingFee(uint256 feeInWei) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    naasRequestingFeeInWei = feeInWei;
  }

  function updateNaasStrongFee(uint256 feeInWei) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    naasStrongFeeInWei = feeInWei;
  }

  function updateClaimingFee(uint256 numerator, uint256 denominator) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    require(denominator != 0);
    claimingFeeNumerator = numerator;
    claimingFeeDenominator = denominator;
  }

  function updateRecurringFee(uint256 feeInWei) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    recurringFeeInWei = feeInWei;
  }

  function updateRecurringNaaSFee(uint256 feeInWei) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    recurringNaaSFeeInWei = feeInWei;
  }

  function updateRecurringPaymentCycleInBlocks(uint256 blocks) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    require(blocks > 0);
    recurringPaymentCycleInBlocks = blocks;
  }

  function updateGracePeriodInBlocks(uint256 blocks) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);
    require(blocks > 0);
    gracePeriodInBlocks = blocks;
  }

  function requestAccess(bool isNaaS) external payable {
    require(entityNodeCount[msg.sender] < maxNodes, "limit reached");

    uint256 rFee;
    uint256 sFee;

    uint128 nodeId = entityNodeCount[msg.sender] + 1;
    bytes memory id = getNodeId(msg.sender, nodeId);

    if (isNaaS) {
      rFee = naasRequestingFeeInWei;
      sFee = naasStrongFeeInWei;
      activeEntities = activeEntities.add(1);
    } else {
      rFee = requestingFeeInWei;
      sFee = strongFeeInWei;
      entityNodeIsBYON[id] = true;
    }

    require(msg.value == rFee, "invalid fee");

    entityNodePaidOnBlock[id] = block.number;
    entityNodeClaimedOnBlock[id] = block.number;
    entityNodeCount[msg.sender] = entityNodeCount[msg.sender] + 1;

    emit Paid(msg.sender, nodeId, entityNodeIsBYON[id], false, entityNodePaidOnBlock[id].add(recurringPaymentCycleInBlocks));

    require(strongToken.transferFrom(msg.sender, address(this), sFee), "transfer failed");
    require(strongToken.transfer(feeCollector, sFee), "transfer failed");
    sendValue(feeCollector, msg.value);
  }

  function setEntityActiveStatus(address entity, bool status) external {
    require(msg.sender == admin || msg.sender == serviceAdmin || msg.sender == superAdmin);
    uint256 index = entityIndex[entity];
    require(entities[index] == entity, "invalid entity");
    require(entityActive[entity] != status, "already set");
    entityActive[entity] = status;
    if (status) {
      activeEntities = activeEntities.add(1);
      entityBlockLastClaimedOn[entity] = block.number;
    } else {
      activeEntities = activeEntities.sub(1);
      entityBlockLastClaimedOn[entity] = 0;
    }
  }

  function payFee(uint128 nodeId, uint256 claimedTotal, bytes calldata signature) public payable {
    address sender = msg.sender == address(this) ? tx.origin : msg.sender;
    bytes memory id = getNodeId(sender, nodeId);

    updateNodeClaimedTotal(sender, nodeId, claimedTotal, signature);

    require(doesNodeExist(sender, nodeId), "doesnt exist");
    require(!hasNodeExpired(sender, nodeId), "too late");
    require(!hasMaxPayments(sender, nodeId), "too soon");

    if (entityNodeIsBYON[id]) {
      require(msg.value == recurringFeeInWei, "invalid fee");
    } else {
      require(msg.value == recurringNaaSFeeInWei, "invalid fee");
    }

    entityNodePaidOnBlock[id] = entityNodePaidOnBlock[id].add(recurringPaymentCycleInBlocks);

    emit Paid(sender, nodeId, entityNodeIsBYON[id], true, entityNodePaidOnBlock[id]);

    sendValue(feeCollector, msg.value);
  }

  function getReward(address entity, uint128 nodeId) external view returns (uint256) {
    return getRewardByBlock(entity, nodeId, block.number);
  }

  function getRewardByBlock(address entity, uint128 nodeId, uint256 blockNumber) public view returns (uint256) {
    bytes memory id = getNodeId(entity, nodeId);

    uint256 blockLastClaimedOn = entityNodeClaimedOnBlock[id] != 0 ? entityNodeClaimedOnBlock[id] : entityNodePaidOnBlock[id];

    if (hasNodeExpired(entity, nodeId)) return 0;
    if (blockNumber > block.number) return 0;
    if (blockLastClaimedOn == 0) return 0;
    if (blockNumber < blockLastClaimedOn) return 0;
    if (activeEntities == 0) return 0;
    if (entityNodeIsBYON[id] && !entityNodeIsActive[id]) return 0;

    uint256 rewardNumerator = entityNodeIsBYON[id] ? rewardPerBlockNumerator : naasRewardPerBlockNumerator;
    uint256 rewardDenominator = entityNodeIsBYON[id] ? rewardPerBlockDenominator : naasRewardPerBlockDenominator;
    uint256 newRewardNumerator = entityNodeIsBYON[id] ? rewardPerBlockNumeratorNew : naasRewardPerBlockNumeratorNew;
    uint256 newRewardDenominator = entityNodeIsBYON[id] ? rewardPerBlockDenominatorNew : naasRewardPerBlockDenominatorNew;

    uint256 bonus = address(strongNFTBonus) != address(0)
    ? strongNFTBonus.getBonus(entity, nodeId, blockLastClaimedOn, blockNumber)
    : 0;

    uint256[2] memory rewardBlocks = rewards.blocks(blockLastClaimedOn, rewardPerBlockNewEffectiveBlock, blockNumber);
    uint256 rewardOld = rewardDenominator > 0 ? rewardBlocks[0].mul(rewardNumerator).div(rewardDenominator) : 0;
    uint256 rewardNew = newRewardDenominator > 0 ? rewardBlocks[1].mul(newRewardNumerator).div(newRewardDenominator) : 0;

    uint256 rewardTotal = rewardOld.add(rewardNew).add(bonus);

    if (nodeLifetimeReward > 0) {
      if (entityNodeClaimedTotal[id] >= nodeLifetimeReward) {
        return 0;
      } else if (entityNodeClaimedTotal[id].add(rewardTotal) > nodeLifetimeReward) {
        return nodeLifetimeReward.sub(entityNodeClaimedTotal[id]);
      }
    }

    return rewardTotal;
  }

  function claim(uint128 nodeId, uint256 blockNumber, bool toStrongPool, uint256 claimedTotal, bytes memory signature) public payable returns (uint256) {
    address sender = msg.sender == address(this) || msg.sender == address(strongNFTBonus) ? tx.origin : msg.sender;
    bytes memory id = getNodeId(sender, nodeId);

    uint256 blockLastClaimedOn = entityNodeClaimedOnBlock[id] != 0 ? entityNodeClaimedOnBlock[id] : entityNodePaidOnBlock[id];
    uint256 blockLastPaidOn = entityNodePaidOnBlock[id];

    require(blockLastClaimedOn != 0, "never claimed");
    require(blockNumber <= block.number, "invalid block");
    require(blockNumber > blockLastClaimedOn, "too soon");
    require(!entityNodeIsBYON[id] || entityNodeIsActive[id], "not active");

    if (
      (!entityNodeIsBYON[id] && recurringNaaSFeeInWei != 0) || (entityNodeIsBYON[id] && recurringFeeInWei != 0)
    ) {
      require(blockNumber < blockLastPaidOn.add(recurringPaymentCycleInBlocks), "pay fee");
    }

    uint256 reward = getRewardByBlock(sender, nodeId, blockNumber);
    require(reward > 0, "no reward");

    uint256 fee = reward.mul(claimingFeeNumerator).div(claimingFeeDenominator);
    require(msg.value >= fee, "invalid fee");

    if (msg.sender != address(this)) {
      updateNodeClaimedTotal(sender, nodeId, claimedTotal, signature);
    }

    rewardBalance = rewardBalance.sub(reward);
    entityNodeClaimedOnBlock[id] = blockNumber;
    entityNodeClaimedTotal[id] = entityNodeClaimedTotal[id].add(reward);

    emit Claimed(sender, reward);

    if (toStrongPool) {
      require(strongToken.approve(address(strongPool), reward), "approve failed");
      strongPool.mineFor(sender, reward);
    } else {
      require(strongToken.transfer(sender, reward), "transfer failed");
    }

    sendValue(feeCollector, fee);

    return fee;
  }

  function getRewardAll(address entity, uint256 blockNumber) public view returns (uint256) {
    uint256 rewardsAll = 0;

    for (uint128 i = 1; i <= entityNodeCount[entity]; i++) {
      rewardsAll = rewardsAll.add(getRewardByBlock(entity, i, blockNumber > 0 ? blockNumber : block.number));
    }

    return rewardsAll;
  }

  function canBePaid(address entity, uint128 nodeId) public view returns (bool) {
    return !isNodeBYON(entity, nodeId) && !hasNodeExpired(entity, nodeId) && !hasMaxPayments(entity, nodeId);
  }

  function doesNodeExist(address entity, uint128 nodeId) public view returns (bool) {
    bytes memory id = getNodeId(entity, nodeId);
    return entityNodePaidOnBlock[id] > 0;
  }

  function hasNodeExpired(address entity, uint128 nodeId) public view returns (bool) {
    bytes memory id = getNodeId(entity, nodeId);
    uint256 blockLastPaidOn = entityNodePaidOnBlock[id];

    if (entityNodeIsBYON[id]) return !entityNodeIsActive[id];
    if (!doesNodeExist(entity, nodeId)) return true;

    return block.number > blockLastPaidOn.add(recurringPaymentCycleInBlocks).add(gracePeriodInBlocks);
  }

  function hasMaxPayments(address entity, uint128 nodeId) public view returns (bool) {
    bytes memory id = getNodeId(entity, nodeId);
    uint256 blockLastPaidOn = entityNodePaidOnBlock[id];
    uint256 limit = block.number.add(recurringPaymentCycleInBlocks.mul(maxPaymentPeriods));

    return blockLastPaidOn.add(recurringPaymentCycleInBlocks) >= limit;
  }

  function getNodeId(address entity, uint128 nodeId) public view returns (bytes memory) {
    uint128 id = nodeId != 0 ? nodeId : entityNodeCount[entity] + 1;
    return abi.encodePacked(entity, id);
  }

  function getNodePaidOn(address entity, uint128 nodeId) external view returns (uint256) {
    bytes memory id = getNodeId(entity, nodeId);
    return entityNodePaidOnBlock[id];
  }

  function getEntityNodeCount(address entity) external view returns (uint256) {
    return entityNodeCount[entity] - entityNodeDeactivatedCount[entity];
  }

  function getEntityNodeClaimedTotal(address entity, uint128 nodeId) public view returns (uint256) {
    return entityNodeClaimedTotal[getNodeId(entity, nodeId)];
  }

  function isNodeActive(address entity, uint128 nodeId) external view returns (bool) {
    bytes memory id = getNodeId(entity, nodeId);
    return entityNodeIsActive[id] || !entityNodeIsBYON[id];
  }

  function isNodeBYON(address entity, uint128 nodeId) public view returns (bool) {
    bytes memory id = getNodeId(entity, nodeId);
    return entityNodeIsBYON[id];
  }

  function sendValue(address payable recipient, uint256 amount) internal {
    require(address(this).balance >= amount, "insufficient balance");

    // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
    (bool success,) = recipient.call{value : amount}("");
    require(success, "send failed");
  }

  function addNFTBonusContract(address _contract) external {
    require(msg.sender == admin || msg.sender == serviceAdmin || msg.sender == superAdmin);

    strongNFTBonus = StrongNFTBonusInterface(_contract);
  }

  function disableNodeAdmin(address entity, uint128 nodeId) external {
    require(msg.sender == admin || msg.sender == serviceAdmin || msg.sender == superAdmin);

    bytes memory id = getNodeId(entity, nodeId);
    entityNodePaidOnBlock[id] = 0;
    entityNodeClaimedOnBlock[id] = 0;

    emit Deactivated(entity, nodeId, entityNodeIsBYON[id], block.number);
  }

  function updateLimits(uint128 _maxNodes, uint256 _maxPaymentPeriods) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);

    maxNodes = _maxNodes;
    maxPaymentPeriods = _maxPaymentPeriods;
  }

  function setTokenContract(IERC20 tokenAddress) external {
    require(msg.sender == superAdmin);
    strongToken = tokenAddress;
  }

  function withdrawToken(IERC20 token, address recipient, uint256 amount) external {
    require(msg.sender == superAdmin);
    require(token.transfer(recipient, amount));
  }

  function updateNodeLifetimeReward(uint256 _nodeLifetimeReward) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);

    nodeLifetimeReward = _nodeLifetimeReward;
  }

  function updateNodeClaimedTotal(address entity, uint128 nodeId, uint256 claimedTotal, bytes memory signature) internal {
    bytes memory id = getNodeId(entity, nodeId);

    if (entityNodeClaimedTotal[id] != 0) {
      return;
    }

    bytes32 hash = prefixed(keccak256(abi.encodePacked(entity, nodeId, claimedTotal)));
    address signer = recoverSigner(hash, signature);

    require(signer == admin || signer == parameterAdmin || signer == superAdmin, "wrong signer");
    entityNodeClaimedTotal[id] = claimedTotal;
  }

  function updateSecondsPerBlock(uint256 _secondsPerBlock) external {
    require(msg.sender == admin || msg.sender == parameterAdmin || msg.sender == superAdmin);

    secondsPerBlock = _secondsPerBlock;
  }

  function migrateAll(address _contract, uint256 _blockNumber, uint256 _totalClaimed, bytes memory signature) external payable {
    bytes32 hash = prefixed(keccak256(abi.encodePacked(msg.sender, _totalClaimed)));
    address signer = recoverSigner(hash, signature);

    require(entityNodeCount[msg.sender] > 0, "0 nodes");
    require(signer == admin || signer == parameterAdmin || signer == superAdmin, "wrong signer");

    uint valueLeft = msg.value;
    uint nodeCount = 0;
    uint totalSeconds = 0;
    uint totalClaimed = _totalClaimed + getRewardAll(msg.sender, _blockNumber);

    for (uint128 nodeId = 1; nodeId <= entityNodeCount[msg.sender]; nodeId++) {
      require(valueLeft > 0, "not enough");
      uint paid = migrate(nodeId, _blockNumber);

      if (paid > 0) {
        nodeCount++;
        valueLeft = valueLeft.sub(paid);
        totalSeconds = totalSeconds.add(block.timestamp
          - ((block.number - entityNodePaidOnBlock[getNodeId(msg.sender, nodeId)]) * secondsPerBlock));
      }
    }

    if (nodeCount == 0) revert("expired");

    entityNodeDeactivatedCount[msg.sender] = entityNodeCount[msg.sender];
    INodePackV3(_contract).migrateNode(msg.sender, 1, nodeCount, totalSeconds / nodeCount, totalClaimed);
    if (valueLeft > 0) sendValue(payable(msg.sender), valueLeft);
  }

  function migrate(uint128 _nodeId, uint256 _blockNumber) internal returns (uint256) {
    address sender = msg.sender == address(this) ? tx.origin : msg.sender;
    bytes memory id = getNodeId(sender, _nodeId);

    uint256 paid = 0;
    if (!hasNodeExpired(sender, _nodeId) && !isNodeBYON(sender, _nodeId)) {
      uint256 fee = getRewardByBlock(sender, _nodeId, _blockNumber).mul(claimingFeeNumerator).div(claimingFeeDenominator);
      paid = this.claim{value : fee}(_nodeId, _blockNumber, false, 0, "0x0");
      strongNFTBonus.unstakeNFT(sender, _nodeId, address(this));
    }

    emit MigratedToNodePack(sender, _nodeId, 1);

    entityNodePaidOnBlock[id] = 0;
    entityNodeClaimedOnBlock[id] = 0;

    return paid;
  }

  // Signatures

  function recoverSigner(bytes32 _hash, bytes memory _sig) public pure returns (address) {
    (uint8 v, bytes32 r, bytes32 s) = splitSignature(_sig);

    return ecrecover(_hash, v, r, s);
  }

  function prefixed(bytes32 _hash) internal pure returns (bytes32) {
    return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", _hash));
  }

  function splitSignature(bytes memory _sig) internal pure returns (uint8 v, bytes32 r, bytes32 s) {
    require(_sig.length == 65);

    assembly {
      r := mload(add(_sig, 32))
      s := mload(add(_sig, 64))
      v := byte(0, mload(add(_sig, 96)))
    }

    return (v, r, s);
  }

}

// SPDX-License-Identifier: MIT

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);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0;

/**
 * @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;
  }
}

// SPDX-License-Identifier: MIT
//pragma solidity ^0.6.12;
pragma solidity >=0.6.0;

interface StrongPoolInterface {
  function mineFor(address miner, uint256 amount) external;
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0;

interface INodePackV3 {
  function doesPackExist(address entity, uint packId) external view returns (bool);

  function hasPackExpired(address entity, uint packId) external view returns (bool);

  function claim(uint packId, uint timestamp, address toStrongPool) external payable returns (uint);

  function getPackId(address _entity, uint _packType) external pure returns (bytes memory);

  function getEntityPackTotalNodeCount(address _entity, uint _packType) external view returns (uint);

  function getEntityPackActiveNodeCount(address _entity, uint _packType) external view returns (uint);

  function migrateNode(address _entity, uint _nodeType, uint _nodeCount, uint _lastPaidAt, uint _totalClaimed) external returns (bool);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0;

/**
 * @dev Required interface of an ERC1155 compliant contract, as defined in the
 * https://eips.ethereum.org/EIPS/eip-1155[EIP].
 *
 * _Available since v3.1._
 */
interface IERC1155Preset {
    /**
     * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.
     */
    event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);

    /**
     * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all
     * transfers.
     */
    event TransferBatch(address indexed operator, address indexed from, address indexed to, uint256[] ids, uint256[] values);

    /**
     * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to
     * `approved`.
     */
    event ApprovalForAll(address indexed account, address indexed operator, bool approved);

    /**
     * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.
     *
     * If an {URI} event was emitted for `id`, the standard
     * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value
     * returned by {IERC1155MetadataURI-uri}.
     */
    event URI(string value, uint256 indexed id);

    /**
     * @dev Returns the amount of tokens of token type `id` owned by `account`.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function balanceOf(address account, uint256 id) external view returns (uint256);

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.
     *
     * Requirements:
     *
     * - `accounts` and `ids` must have the same length.
     */
    function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids) external view returns (uint256[] memory);

    /**
     * @dev Grants or revokes permission to `operator` to transfer the caller's tokens, according to `approved`,
     *
     * Emits an {ApprovalForAll} event.
     *
     * Requirements:
     *
     * - `operator` cannot be the caller.
     */
    function setApprovalForAll(address operator, bool approved) external;

    /**
     * @dev Returns true if `operator` is approved to transfer ``account``'s tokens.
     *
     * See {setApprovalForAll}.
     */
    function isApprovedForAll(address account, address operator) external view returns (bool);

    /**
     * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.
     *
     * Emits a {TransferSingle} event.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - If the caller is not `from`, it must be have been approved to spend ``from``'s tokens via {setApprovalForAll}.
     * - `from` must have a balance of tokens of type `id` of at least `amount`.
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
     * acceptance magic value.
     */
    function safeTransferFrom(address from, address to, uint256 id, uint256 amount, bytes calldata data) external;

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.
     *
     * Emits a {TransferBatch} event.
     *
     * Requirements:
     *
     * - `ids` and `amounts` must have the same length.
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
     * acceptance magic value.
     */
    function safeBatchTransferFrom(address from, address to, uint256[] calldata ids, uint256[] calldata amounts, bytes calldata data) external;

    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);

    /**
     * @dev Creates `amount` new tokens for `to`, of token type `id`.
     *
     * See {ERC1155-_mint}.
     *
     * Requirements:
     *
     * - the caller must have the `MINTER_ROLE`.
     */
    function mint(address to, uint256 id, uint256 amount, bytes memory data) external;

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] variant of {mint}.
     */
    function mintBatch(address to, uint256[] memory ids, uint256[] memory amounts, bytes memory data) external;

    function getOwnerIdByIndex(address owner, uint256 index) external view returns (uint256);

    function getOwnerIdIndex(address owner, uint256 id) external view returns (uint256);
}

// SPDX-License-Identifier: MIT
//pragma solidity ^0.6.12;
pragma solidity >=0.6.0;

interface StrongNFTBonusInterface {
  function getBonus(address _entity, uint128 _nodeId, uint256 _from, uint256 _to) external view returns (uint256);

  function getBonusValue(address _entity, uint128 _nodeId, uint256 _from, uint256 _to, uint256 _bonusValue) external view returns (uint256);

  function getStakedNftBonusName(address _entity, uint128 _nodeId, address _serviceContract) external view returns (string memory);

  function migrateNFT(address _entity, uint128 _fromNodeId, uint128 _toNodeId, address _toServiceContract) external;

  function unstakeNFT(address _entity, uint128 _nodeId, address _serviceContract) external;
}

// SPDX-License-Identifier: MIT
//pragma solidity 0.6.12;
pragma solidity >=0.6.0;

import "./SafeMath.sol";

library rewards {

    using SafeMath for uint256;

    function blocks(uint256 lastClaimedOnBlock, uint256 newRewardBlock, uint256 blockNumber) internal pure returns (uint256[2] memory) {
        if (lastClaimedOnBlock >= blockNumber) return [uint256(0), uint256(0)];

        if (blockNumber <= newRewardBlock || newRewardBlock == 0) {
            return [blockNumber.sub(lastClaimedOnBlock), uint256(0)];
        }
        else if (lastClaimedOnBlock >= newRewardBlock) {
            return [uint256(0), blockNumber.sub(lastClaimedOnBlock)];
        }
        else {
            return [newRewardBlock.sub(lastClaimedOnBlock), blockNumber.sub(newRewardBlock)];
        }
    }

}