Governance v3 (#1984)

auxiliary/RewardsDistributor/cannonfile.snapshot.toml

@@ -0,0 +1,27 @@
+name = "synthetix-snapshot-rewards"
+version = "<%= package.version %>"
+description = "Maintains snapshots of account balances in a pool"
+
+[setting.synthetixPackage]
+defaultValue = "synthetix:latest@main"
+
+[setting.servicePoolId]
+defaultValue = "0"
+
+[setting.serviceCollateralAddress]
+defaultValue = "<%= AddressZero %>"
+
+[setting.snapper]
+defaultValue = "<%= AddressZero %>"
+
+[import.synthetix]
+source = "<%= settings.synthetixPackage %>"
+
+[contract.RewardsDistributor]
+artifact = "SnapshotRewardsDistributor"
+args = [
+    "<%= imports.synthetix.contracts.CoreProxy.address %>",
+    "<%= settings.servicePoolId %>",
+    "<%= settings.serviceCollateralAddress %>",
+    "<%= settings.snapper %>",
+]

auxiliary/RewardsDistributor/src/SnapshotRewardsDistributor.sol

@@ -0,0 +1,251 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+import {ERC2771Context} from "@synthetixio/core-contracts/contracts/utils/ERC2771Context.sol";
+import {IERC721} from "@synthetixio/core-contracts/contracts/interfaces/IERC721.sol";
+import {IRewardDistributor} from "@synthetixio/main/contracts/interfaces/external/IRewardDistributor.sol";
+import {AccessError} from "@synthetixio/core-contracts/contracts/errors/AccessError.sol";
+import {ParameterError} from "@synthetixio/core-contracts/contracts/errors/ParameterError.sol";
+import {IERC165} from "@synthetixio/core-contracts/contracts/interfaces/IERC165.sol";
+import {ISnapshotRecord} from "@synthetixio/governance/contracts/interfaces/external/ISnapshotRecord.sol";
+import {IAccountModule} from "@synthetixio/main/contracts/interfaces/IAccountModule.sol";
+import {IVaultModule} from "@synthetixio/main/contracts/interfaces/IVaultModule.sol";
+
+contract SnapshotRewardsDistributor is IRewardDistributor, ISnapshotRecord {
+    error AccountNotFound();
+
+    address private rewardsManager;
+    IERC721 private accountToken;
+    uint128 public servicePoolId;
+    address public serviceCollateralType;
+
+    struct PeriodBalance {
+        uint128 amount;
+        uint128 periodId;
+        address owner;
+    }
+
+    /**
+     * Addresses selected by owner which are allowed to call `takeSnapshot`
+     * `takeSnapshot` is not public because only a small number of snapshots can be retained for a period of time, and so they
+     * must be controlled to prevent censorship
+     */
+    mapping(address => bool) public authorizedToSnapshot;
+
+    /**
+     * Records a user's balance as it changes from period to period.
+     * The last item in the array always represents the user's most recent balance
+     * The intermediate balance is only recorded if
+     * `currentPeriodId` differs (which would happen upon a call to `setCurrentPeriodId`)
+     */
+    mapping(uint128 => PeriodBalance[]) public balances;
+
+    /**
+     * Records totalSupply as it changes from period to period
+     * Similar to `balances`, the `totalSupplyOnPeriod` at index `currentPeriodId` matches the current total supply
+     * Any other period ID would represent its most recent totalSupply before the period ID changed.
+     */
+    mapping(uint256 => uint256) public totalSupplyOnPeriod;
+
+    /**
+     * Records the latest address to which account it is part of
+     */
+    mapping(address => PeriodBalance[]) private accountBalances;
+
+    uint128 public currentPeriodId;
+
+    uint256 internal constant MAX_PERIOD_ITERATE = 30;
+
+    constructor(
+        address _rewardsManager, // SynthetixCoreProxy
+        uint128 _servicePoolId,
+        address _serviceCollateralType,
+        address snapper
+    ) {
+        servicePoolId = _servicePoolId;
+        serviceCollateralType = _serviceCollateralType;
+        rewardsManager = _rewardsManager;
+        accountToken = IERC721(IAccountModule(rewardsManager).getAccountTokenAddress());
+        authorizedToSnapshot[snapper] = true;
+    }
+
+    function onPositionUpdated(
+        uint128 accountId,
+        uint128 poolId,
+        address collateralType,
+        uint256 // actorSharesD18
+    ) external {
+        address sender = ERC2771Context._msgSender();
+        if (sender != rewardsManager) {
+            revert AccessError.Unauthorized(sender);
+        }
+
+        if (poolId != servicePoolId) {
+            revert ParameterError.InvalidParameter(
+                "poolId",
+                "Pool does not match the rewards pool"
+            );
+        }
+
+        if (collateralType != serviceCollateralType) {
+            revert ParameterError.InvalidParameter(
+                "collateralType",
+                "Collateral does not match the rewards token"
+            );
+        }
+
+        // get current account information
+        uint256 newAmount = IVaultModule(rewardsManager).getPositionCollateral(
+            accountId,
+            poolId,
+            collateralType
+        );
+        address account = accountToken.ownerOf(accountId);
+
+        // ensure periods for all the values we will be updating are correct
+        uint256 idIdx = updatePeriod(balances[accountId]);
+        uint256 oldAccountIdx = updatePeriod(accountBalances[balances[accountId][idIdx].owner]);
+        uint256 accountIdx = updatePeriod(accountBalances[account]);
+
+        uint256 prevBalance = balances[accountId][idIdx].amount;
+
+        // subtract balance from previous owner
+        // solhint-disable-next-line
+        accountBalances[balances[accountId][idIdx].owner][oldAccountIdx].amount -= uint128(
+            prevBalance
+        );
+
+        // add balance to new owner
+        // solhint-disable-next-line
+        accountBalances[account][accountIdx].amount += uint128(newAmount);
+
+        // update account id record
+        // solhint-disable-next-line
+        balances[accountId][idIdx].amount = uint128(newAmount);
+        balances[accountId][idIdx].owner = account;
+
+        totalSupplyOnPeriod[currentPeriodId] =
+            totalSupplyOnPeriod[currentPeriodId] +
+            newAmount -
+            prevBalance;
+    }
+
+    function updatePeriod(PeriodBalance[] storage bals) internal returns (uint256) {
+        uint256 balanceCount = bals.length;
+        if (balanceCount == 0 || bals[balanceCount - 1].periodId != currentPeriodId) {
+            // solhint-disable-next-line
+            bals.push(PeriodBalance(0, uint128(currentPeriodId), address(0)));
+
+            if (balanceCount > 0) {
+                bals[balanceCount].amount = bals[balanceCount - 1].amount;
+                bals[balanceCount].owner = bals[balanceCount - 1].owner;
+            }
+
+            balanceCount++;
+        }
+
+        return balanceCount - 1;
+    }
+
+    function balanceOfOnPeriod(address account, uint256 periodId) public view returns (uint256) {
+        uint256 accountPeriodHistoryCount = accountBalances[account].length;
+        // solhint-disable-next-line
+        int256 oldestHistoryIterate = int256(
+            MAX_PERIOD_ITERATE < accountPeriodHistoryCount
+                ? accountPeriodHistoryCount - MAX_PERIOD_ITERATE
+                : 0
+        );
+        int256 i;
+        // solhint-disable-next-line
+        for (i = int256(accountPeriodHistoryCount) - 1; i >= oldestHistoryIterate; i--) {
+            // solhint-disable-next-line
+            if (accountBalances[account][uint256(i)].periodId <= periodId) {
+                // solhint-disable-next-line
+                return uint256(accountBalances[account][uint256(i)].amount);
+            }
+        }
+
+        if (i >= 0) {
+            revert AccountNotFound();
+        }
+
+        return 0;
+    }
+
+    function balanceOfOnPeriod(uint128 accountId, uint256 periodId) public view returns (uint256) {
+        uint256 accountPeriodHistoryCount = balances[accountId].length;
+        // solhint-disable-next-line
+        int256 oldestHistoryIterate = int256(
+            MAX_PERIOD_ITERATE < accountPeriodHistoryCount
+                ? accountPeriodHistoryCount - MAX_PERIOD_ITERATE
+                : 0
+        );
+        int256 i;
+        // solhint-disable-next-line
+        for (i = int256(accountPeriodHistoryCount) - 1; i >= oldestHistoryIterate; i--) {
+            // solhint-disable-next-line
+            if (balances[accountId][uint256(i)].periodId <= periodId) {
+                // solhint-disable-next-line
+                return uint256(balances[accountId][uint256(i)].amount);
+            }
+        }
+
+        if (i >= 0) {
+            revert AccountNotFound();
+        }
+
+        return 0;
+    }
+
+    function balanceOf(uint128 accountId) external view returns (uint256) {
+        return balanceOfOnPeriod(accountId, currentPeriodId);
+    }
+
+    function balanceOf(address user) external view returns (uint256) {
+        return balanceOfOnPeriod(user, currentPeriodId);
+    }
+
+    function totalSupply() external view returns (uint256) {
+        return totalSupplyOnPeriod[currentPeriodId];
+    }
+
+    function takeSnapshot(uint128 id) external {
+        address sender = ERC2771Context._msgSender();
+        if (!authorizedToSnapshot[sender]) {
+            revert AccessError.Unauthorized(sender);
+        }
+        if (id <= currentPeriodId) {
+            revert ParameterError.InvalidParameter("id", "period id must always increase");
+        }
+        totalSupplyOnPeriod[id] = totalSupplyOnPeriod[currentPeriodId];
+        currentPeriodId = id;
+    }
+
+    function payout(
+        uint128, // accountId
+        uint128, // poolId_
+        address, // collateralType_
+        address, // payoutTarget_
+        uint256 // payoutAmount_
+    ) external pure returns (bool) {
+        // this is not a rewards distributor that pays out any tokens
+        return true;
+    }
+
+    function name() public pure override returns (string memory) {
+        return "snapshot tracker for governance";
+    }
+
+    function token() public pure override returns (address) {}
+
+    /**
+     * @dev See {IERC165-supportsInterface}.
+     */
+    function supportsInterface(
+        bytes4 interfaceId
+    ) public view virtual override(IERC165) returns (bool) {
+        return
+            interfaceId == type(IRewardDistributor).interfaceId ||
+            interfaceId == this.supportsInterface.selector;
+    }
+}