Progress on validation pool

ethereum/contracts/DAO.sol

@@ -7,7 +7,7 @@ import "./ReputationHolder.sol";
 struct Stake {
     bool inFavor;
     uint256 amount;
-    address worker;
+    address sender;
 }
 
 enum ValidationPoolStatus {
@@ -19,6 +19,13 @@ struct ValidationPool {
     mapping(uint => Stake) stakes;
     uint stakeCount;
     ValidationPoolStatus status;
+    uint duration;
+    uint endTime;
+}
+
+struct StakeData {
+    uint validationPoolIndex;
+    bool inFavor;
 }
 
 /// This contract must manage validation pools and reputation,
@@ -30,11 +37,24 @@ contract DAO is ERC721("Reputation", "REP"), ReputationHolder {
     mapping(uint => ValidationPool) validationPools;
     uint validationPoolCount;
 
+    event ValidationPoolInitiated(uint validationPoolIndex);
+
     /// Inspect the value of a given reputation NFT
     function valueOf(uint256 tokenId) public view returns (uint256 value) {
         value = tokenValues[tokenId];
     }
 
+    /// Confirm ownership of a token and return its value.
+    /// This should be used when receiving an NFT transfer, because otherwise
+    /// someone could send any NFT with a tokenId matching one of ours.
+    function verifiedValueOf(
+        address owner,
+        uint256 tokenId
+    ) public view returns (uint256 value) {
+        require(ownerOf(tokenId) == owner);
+        value = valueOf(tokenId);
+    }
+
     /// Internal function to mint a new reputation NFT
     function mint() internal returns (uint256 tokenId) {
         // Generate a new (sequential) ID for the token
@@ -56,15 +76,35 @@ contract DAO is ERC721("Reputation", "REP"), ReputationHolder {
     }
 
     /// Accept fee to initiate a validation pool
-    function initiateValidationPool() public {}
+    function initiateValidationPool(uint duration) public {
+        uint validationPoolIndex = validationPoolCount++;
+        ValidationPool storage pool = validationPools[validationPoolIndex];
+        pool.duration = duration;
+        pool.endTime = block.timestamp + duration;
+        emit ValidationPoolInitiated(validationPoolIndex);
+    }
 
     /// Accept reputation stakes toward a validation pool
     function onERC721Received(
         address,
         address from,
         uint256 tokenId,
-        bytes calldata
+        bytes calldata data
     ) public override returns (bytes4) {
+        // `data` needs to encode the target validation pool, and the for/again boolean
+        StakeData memory stakeParameters = abi.decode(data, (StakeData));
+        ValidationPool storage pool = validationPools[
+            stakeParameters.validationPoolIndex
+        ];
+        Stake storage stake = pool.stakes[pool.stakeCount++];
+        stake.sender = from;
+        stake.inFavor = stakeParameters.inFavor;
+        stake.amount = verifiedValueOf(from, tokenId);
         return super.onERC721Received.selector;
     }
+
+    /// Evaluate outcome of a validation pool
+    function evaluateOutcome(
+        uint validationPoolIndex
+    ) public returns (bool outcome) {}
 }

ethereum/contracts/Work1.sol

@@ -51,7 +51,8 @@ contract Work1 is ReputationHolder {
         AvailabilityStake storage stake = stakes[stakeCount++];
         stake.worker = from;
         stake.tokenId = tokenId;
-        stake.amount = dao.valueOf(tokenId);
+        stake.amount = dao.verifiedValueOf(from, tokenId);
+        // TODO: use `data` parameter to include stake options such as duration
         return super.onERC721Received.selector;
     }
 
@@ -67,7 +68,7 @@ contract Work1 is ReputationHolder {
         for (uint i = 0; i < stakeCount; i++) {
             if (stakes[i].assigned) continue;
             acc += stakes[i].amount;
-            if (acc >= select) return i;
+            if (acc > select) return i;
         }
         revert("Failed to select worker");
     }