Merge pull request poanetwork#5 from lukso-network/aura-to-hbbft-term…

…inology

Aura to hbbft terminology

contracts/TxPermissionHbbft.sol

@@ -221,7 +221,7 @@ contract TxPermissionHbbft is UpgradeableOwned, ITxPermission {
     /// staking epoch: the block gas limit is temporarily reduced for the latest block of the epoch.
     function blockGasLimit() public view returns(uint256) {
         address stakingContract = validatorSetContract.stakingContract();
-        uint256 stakingEpochEndBlock = IStakingHbbft(stakingContract).stakingEpochEndBlock();
+        uint256 stakingEpochEndBlock = IStakingHbbft(stakingContract).stakingFixedEpochEndBlock();
         if (block.number == stakingEpochEndBlock - 1 || block.number == stakingEpochEndBlock) {
             return BLOCK_GAS_LIMIT_REDUCED;
         }

contracts/ValidatorSetHbbft.sol

@@ -732,9 +732,9 @@ contract ValidatorSetHbbft is UpgradeabilityAdmin, IValidatorSetHbbft {
     /// @dev Returns the future block number until which a validator is banned.
     /// Used by the `_removeMaliciousValidator` internal function.
     function _banUntil() internal view returns(uint256) {
-        uint256 blocksUntilEnd = stakingContract.stakingEpochEndBlock() - _getCurrentBlockNumber();
+        uint256 blocksUntilEnd = stakingContract.stakingFixedEpochEndBlock() - _getCurrentBlockNumber();
         // ~90 days, at least 12 full staking epochs (for 5 seconds block)
-        return _getCurrentBlockNumber() + 12 * stakingContract.stakingEpochDuration() + blocksUntilEnd;
+        return _getCurrentBlockNumber() + 12 * stakingContract.stakingFixedEpochDuration() + blocksUntilEnd;
     }
 
     /// @dev Returns the current block number. Needed mostly for unit tests.

contracts/base/BlockRewardHbbftBase.sol

@@ -218,10 +218,10 @@ contract BlockRewardHbbftBase is UpgradeableOwned, IBlockRewardHbbft {
 
     /// @dev Called by the validator's node when producing and closing a block,
     /// see https://wiki.parity.io/Block-Reward-Contract.html.
-    /// This function performs all of the automatic operations needed for controlling secrets revealing by validators,
-    /// accumulating block producing statistics, starting a new staking epoch, snapshotting staking amounts
-    /// for the upcoming staking epoch, rewards distributing at the end of a staking epoch, and minting
-    /// native coins needed for the `erc-to-native` bridge.
+    /// This function performs all of the automatic operations needed for accumulating block producing statistics,
+    /// starting a new staking epoch, snapshotting staking amounts for the upcoming staking epoch,
+    /// rewards distributing at the end of a staking epoch, 
+    /// and minting native coins needed for the `erc-to-native` bridge.
     function reward(address[] calldata benefactors, uint16[] calldata kind)
         external
         onlySystem
@@ -236,10 +236,6 @@ contract BlockRewardHbbftBase is UpgradeableOwned, IBlockRewardHbbft {
             return (new address[](0), new uint256[](0));
         }
 
-        // Check the current validators at the end of each collection round whether
-        // they revealed their secrets, and remove a validator as a malicious if needed
-        // IRandomHbbft(validatorSetContract.randomContract()).onFinishCollectRound();
-
         // Initialize the extra receivers queue
         if (!_queueERInitialized) {
             _queueERFirst = 1;
@@ -250,7 +246,7 @@ contract BlockRewardHbbftBase is UpgradeableOwned, IBlockRewardHbbft {
         uint256 bridgeQueueLimit = 100;
         IStakingHbbft stakingContract = IStakingHbbft(validatorSetContract.stakingContract());
         uint256 stakingEpoch = stakingContract.stakingEpoch();
-        uint256 stakingEpochEndBlock = stakingContract.stakingEpochEndBlock();
+        uint256 stakingFixedEpochEndBlock = stakingContract.stakingFixedEpochEndBlock();
         uint256 nativeTotalRewardAmount = 0;
 
         if (validatorSetContract.validatorSetApplyBlock() != 0) {
@@ -262,27 +258,27 @@ contract BlockRewardHbbftBase is UpgradeableOwned, IBlockRewardHbbft {
             }
         }
 
-        if (_getCurrentBlockNumber() == stakingEpochEndBlock) {
+        if (_getCurrentBlockNumber() == stakingFixedEpochEndBlock) {
             // Distribute rewards among validator pools
             if (stakingEpoch != 0) {
                 nativeTotalRewardAmount = _distributeRewards(
                     stakingContract,
                     stakingEpoch,
-                    stakingEpochEndBlock
+                    stakingFixedEpochEndBlock
                 );
             }
 
-            // Choose new validators
-            validatorSetContract.newValidatorSet();
 
-            // Snapshot total amounts staked into the pools
+             // Snapshot total amounts staked into the pools
             uint256 i;
             uint256 nextStakingEpoch = stakingEpoch + 1;
             address[] memory miningAddresses;
-
+
+            // Choose new validators
+            validatorSetContract.newValidatorSet();
+
             // We need to remember the total staked amounts for the pending addresses
-            // for the possible case when these pending addresses are finalized
-            // by the `ValidatorSetHbbft.finalizeChange` function and thus become validators
+            // for when these pending addresses are finalized by `ValidatorSetHbbft.finalizeChange()`.
             miningAddresses = validatorSetContract.getPendingValidators();
             for (i = 0; i < miningAddresses.length; i++) {
                 _snapshotPoolStakeAmounts(stakingContract, nextStakingEpoch, miningAddresses[i]);
@@ -297,16 +293,6 @@ contract BlockRewardHbbftBase is UpgradeableOwned, IBlockRewardHbbft {
                 _snapshotPoolStakeAmounts(stakingContract, nextStakingEpoch, miningAddresses[i]);
             }
 
-            // We need to remember the total staked amounts for the addresses currently
-            // being finalized but not yet finalized (i.e. the `InitiateChange` event is emitted
-            // for them but not yet handled by validator nodes thus the `ValidatorSetHbbft.finalizeChange`
-            // function is not called yet) for the possible case when these addresses finally
-            // become validators on the upcoming staking epoch
-            miningAddresses = validatorSetContract.getPendingValidators();
-            for (i = 0; i < miningAddresses.length; i++) {
-                _snapshotPoolStakeAmounts(stakingContract, nextStakingEpoch, miningAddresses[i]);
-            }
-
             // Remember validator's min reward percent for the upcoming staking epoch
             validatorMinRewardPercent[nextStakingEpoch] = VALIDATOR_MIN_REWARD_PERCENT;
 
@@ -614,13 +600,13 @@ contract BlockRewardHbbftBase is UpgradeableOwned, IBlockRewardHbbft {
     /// This function is called by the `reward` function.
     /// @param _stakingContract The address of the StakingHbbft contract.
     /// @param _stakingEpoch The number of the current staking epoch.
-    /// @param _stakingEpochEndBlock The number of the latest block of the current staking epoch.
+    /// @param _stakingFixedEpochEndBlock The number of the latest block before key generation begins.
     /// @return Returns the reward amount in native coins needed to be minted
     /// and accrued to the balance of this contract.
     function _distributeRewards(
         IStakingHbbft _stakingContract,
         uint256 _stakingEpoch,
-        uint256 _stakingEpochEndBlock
+        uint256 _stakingFixedEpochEndBlock
     ) internal returns(uint256 nativeTotalRewardAmount) {
         address[] memory validators = validatorSetContract.getValidators();
 
@@ -636,8 +622,8 @@ contract BlockRewardHbbftBase is UpgradeableOwned, IBlockRewardHbbft {
                 realFinalizeBlock = idealFinalizeBlock;
             }
 
-            totalRewardShareNum = _stakingEpochEndBlock - realFinalizeBlock + 1;
-            totalRewardShareDenom = _stakingEpochEndBlock - idealFinalizeBlock + 1;
+            totalRewardShareNum = _stakingFixedEpochEndBlock - realFinalizeBlock + 1;
+            totalRewardShareDenom = _stakingFixedEpochEndBlock - idealFinalizeBlock + 1;
         }
 
         uint256[] memory blocksCreatedShareNum = new uint256[](validators.length);

contracts/base/StakingHbbftBase.sol

@@ -122,8 +122,8 @@ contract StakingHbbftBase is UpgradeableOwned, IStakingHbbft {
     /// @dev The serial number of the current staking epoch.
     uint256 public stakingEpoch;
 
-    /// @dev The duration of a staking epoch in blocks.
-    uint256 public stakingEpochDuration;
+    /// @dev The fixed duration of each staking epoch before KeyGen starts i.e. before the upcoming ("pending") validators are selected.
+    uint256 public stakingFixedEpochDuration;
 
     /// @dev The number of the first block of the current staking epoch.
     uint256 public stakingEpochStartBlock;
@@ -299,7 +299,7 @@ contract StakingHbbftBase is UpgradeableOwned, IStakingHbbft {
     /// @param _initialStakingAddresses The array of initial validators' staking addresses.
     /// @param _delegatorMinStake The minimum allowed amount of delegator stake in Wei.
     /// @param _candidateMinStake The minimum allowed amount of candidate/validator stake in Wei.
-    /// @param _stakingEpochDuration The duration of a staking epoch in blocks
+    /// @param _stakingFixedEpochDuration The fixed duration of each epoch before keyGen starts in blocks
     /// @param _stakingEpochStartBlock The number of the first block of initial staking epoch
     /// (must be zero if the network is starting from genesis block).
     /// @param _stakeWithdrawDisallowPeriod The duration period (in blocks) at the end of a staking epoch
@@ -309,14 +309,14 @@ contract StakingHbbftBase is UpgradeableOwned, IStakingHbbft {
         address[] calldata _initialStakingAddresses,
         uint256 _delegatorMinStake,
         uint256 _candidateMinStake,
-        uint256 _stakingEpochDuration,
+        uint256 _stakingFixedEpochDuration,
         uint256 _stakingEpochStartBlock,
         uint256 _stakeWithdrawDisallowPeriod,
         bytes32[] calldata _publicKeys,
         bytes16[] calldata _internetAddresses
     ) external {
-        require(_stakingEpochDuration != 0);
-        require(_stakingEpochDuration > _stakeWithdrawDisallowPeriod);
+        require(_stakingFixedEpochDuration != 0);
+        require(_stakingFixedEpochDuration > _stakeWithdrawDisallowPeriod);
         require(_stakeWithdrawDisallowPeriod != 0);
         _initialize(
             _validatorSetContract,
@@ -326,7 +326,7 @@ contract StakingHbbftBase is UpgradeableOwned, IStakingHbbft {
             _publicKeys,
             _internetAddresses
         );
-        stakingEpochDuration = _stakingEpochDuration;
+        stakingFixedEpochDuration = _stakingFixedEpochDuration;
         stakeWithdrawDisallowPeriod = _stakeWithdrawDisallowPeriod;
         stakingEpochStartBlock = _stakingEpochStartBlock;
     }
@@ -600,7 +600,7 @@ contract StakingHbbftBase is UpgradeableOwned, IStakingHbbft {
     /// Used by all staking/withdrawal functions.
     function areStakeAndWithdrawAllowed() public view returns(bool) {
         uint256 currentBlock = _getCurrentBlockNumber();
-        uint256 allowedDuration = stakingEpochDuration - stakeWithdrawDisallowPeriod;
+        uint256 allowedDuration = stakingFixedEpochDuration - stakeWithdrawDisallowPeriod; //TODO: should it be extended to the start of the block, e.g. startBlock -1
         if (currentBlock < stakingEpochStartBlock) return false;
         return currentBlock - stakingEpochStartBlock <= allowedDuration; //TODO: should be < not <=?
     }
@@ -709,10 +709,10 @@ contract StakingHbbftBase is UpgradeableOwned, IStakingHbbft {
         return _stakeAmountByEpoch[_poolStakingAddress][_staker][stakingEpoch];
     }
 
-    /// @dev Returns the number of the last block of the current staking epoch.
-    function stakingEpochEndBlock() public view returns(uint256) {
+    /// @dev Returns the number of the last block of the current staking epoch before key generation starts.
+    function stakingFixedEpochEndBlock() public view returns(uint256) {
         uint256 startBlock = stakingEpochStartBlock;
-        return startBlock + stakingEpochDuration - (startBlock == 0 ? 0 : 1);
+        return startBlock + stakingFixedEpochDuration - (startBlock == 0 ? 0 : 1);
     }
 
     // ============================================== Internal ========================================================

contracts/interfaces/IStakingHbbft.sol

@@ -31,7 +31,7 @@ interface IStakingHbbft {
     function stakeLastEpoch(address, address) external view returns(uint256);
     function stakeWithdrawDisallowPeriod() external view returns(uint256);
     function stakingEpoch() external view returns(uint256);
-    function stakingEpochDuration() external view returns(uint256);
-    function stakingEpochEndBlock() external view returns(uint256);
+    function stakingFixedEpochDuration() external view returns(uint256);
+    function stakingFixedEpochEndBlock() external view returns(uint256);
     function stakingEpochStartBlock() external view returns(uint256);
 }