refactor: account for staking contract deposit value

contracts/staking/StakingFactory.sol

@@ -332,18 +332,14 @@ contract StakingFactory {
         bool success = verifyInstance(instance);
 
         if (success) {
-            // Get the proxy instance emissions amount
-            amount = IStaking(instance).emissionsAmount();
-
-            // If there is a verifier, adjust the amount
+            // If there is a verifier, get the emissions amount
             address localVerifier = verifier;
             if (localVerifier != address(0)) {
                 // Get the max possible emissions amount
-                uint256 maxEmissions = IStakingVerifier(localVerifier).getEmissionsAmountLimit(instance);
-                // Limit excessive emissions amount
-                if (amount > maxEmissions) {
-                    amount = maxEmissions;
-                }
+                amount = IStakingVerifier(localVerifier).getEmissionsAmountLimit(instance);
+            } else {
+                // Get the proxy instance emissions amount
+                amount = IStaking(instance).emissionsAmount();
             }
         }
     }

contracts/staking/StakingVerifier.sol

@@ -11,6 +11,14 @@ interface IStaking {
     /// @return Maximum number of services.
     function maxNumServices() external view returns (uint256);
 
+    /// @dev Gets time for emissions.
+    /// @return Time for emissions.
+    function timeForEmissions() external view returns (uint256);
+
+    /// @dev Gets emissions amount.
+    /// @return Emissions amount.
+    function emissionsAmount() external view returns (uint256);
+
     /// @dev Gets service staking token.
     /// @return Service staking token address.
     function stakingToken() external view returns (address);
@@ -22,6 +30,10 @@ interface IStaking {
     /// @dev Gets service registry token utility address.
     /// @return Service registry token utility address.
     function serviceRegistryTokenUtility() external view returns(address);
+
+    /// @dev Minimum service staking deposit value required for staking.
+    /// @return Minimum service staking deposit.
+    function minStakingDeposit() external view returns(uint256);
 }
 
 /// @dev Provided zero address.
@@ -52,24 +64,26 @@ contract StakingVerifier {
     event OwnerUpdated(address indexed owner);
     event SetImplementationsCheck(bool setCheck);
     event ImplementationsWhitelistUpdated(address[] implementations, bool[] statuses, bool setCheck);
-    event StakingLimitsUpdated(uint256 rewardsPerSecondLimit, uint256 timeForEmissionsLimit, uint256 _numServicesLimit,
-        uint256 emissionsLimit);
+    event StakingLimitsUpdated(uint256 minStakingDepositLimit, uint256 timeForEmissionsLimit, uint256 numServicesLimit,
+        uint256 apyLimit);
 
+    // One year constant
+    uint256 public constant ONE_YEAR = 1 days * 365;
     // OLAS token address
     address public immutable olas;
     // Service registry address
     address public immutable serviceRegistry;
     // Service registry token utility
     address public immutable serviceRegistryTokenUtility;
 
-    // Rewards per second limit
-    uint256 public rewardsPerSecondLimit;
+    // Minimum staking deposit limit
+    uint256 public minStakingDepositLimit;
     // Time for emissions limit
     uint256 public timeForEmissionsLimit;
     // Limit for the number of services
     uint256 public numServicesLimit;
-    // Emissions per service limit
-    uint256 public emissionsLimit;
+    // APY limit in 1e18 format
+    uint256 public apyLimit;
     // Contract owner address
     address public owner;
     // Flag to check for the implementation address whitelisting status
@@ -82,35 +96,37 @@ contract StakingVerifier {
     /// @param _olas OLAS token address.
     /// @param _serviceRegistry Service registry address.
     /// @param _serviceRegistryTokenUtility Service registry token utility address.
-    /// @param _rewardsPerSecondLimit Rewards per second limit.
+    /// @param _minStakingDepositLimit Minimum staking deposit limit.
     /// @param _timeForEmissionsLimit Time for emissions limit.
     /// @param _numServicesLimit Limit for the number of services.
+    /// @param _apyLimit APY limit in 1e18 format.
     constructor(
         address _olas,
         address _serviceRegistry,
         address _serviceRegistryTokenUtility,
-        uint256 _rewardsPerSecondLimit,
+        uint256 _minStakingDepositLimit,
         uint256 _timeForEmissionsLimit,
-        uint256 _numServicesLimit
+        uint256 _numServicesLimit,
+        uint256 _apyLimit
     ) {
         // Zero address check
         if (_olas == address(0) || _serviceRegistry == address(0)) {
             revert ZeroAddress();
         }
 
         // Zero values check
-        if (_rewardsPerSecondLimit == 0 || _timeForEmissionsLimit == 0 || _numServicesLimit == 0) {
+        if (_minStakingDepositLimit == 0 || _timeForEmissionsLimit == 0 || _numServicesLimit == 0 || _apyLimit == 0) {
             revert ZeroValue();
         }
 
         owner = msg.sender;
         olas = _olas;
         serviceRegistry = _serviceRegistry;
         serviceRegistryTokenUtility = _serviceRegistryTokenUtility;
-        rewardsPerSecondLimit = _rewardsPerSecondLimit;
+        minStakingDepositLimit = _minStakingDepositLimit;
         timeForEmissionsLimit = _timeForEmissionsLimit;
         numServicesLimit = _numServicesLimit;
-        emissionsLimit = _rewardsPerSecondLimit * _timeForEmissionsLimit * _numServicesLimit;
+        apyLimit = _apyLimit;
     }
 
     /// @dev Changes the owner address.
@@ -225,10 +241,27 @@ contract StakingVerifier {
             return false;
         }
 
-        // Check for the staking parameters
+        // Check for minimum staking deposit
+        // Get instance min staking deposit
+        uint256 minStakingDeposit = IStaking(instance).minStakingDeposit();
+        if (minStakingDeposit > minStakingDepositLimit) {
+            return false;
+        }
+
+        // Calculate rewards per year
+        uint256 rewardsPerYear = IStaking(instance).rewardsPerSecond() * ONE_YEAR;
+        // Calculate current APY in 1e18 format
+        uint256 apy = (rewardsPerYear * 1e18) / minStakingDeposit;
+
+        // Compare APY with the limit
+        if (apy > apyLimit) {
+            return false;
+        }
+
+        // Check for time for emissions
         // This is a must have parameter for all staking contracts
-        uint256 rewardsPerSecond = IStaking(instance).rewardsPerSecond();
-        if (rewardsPerSecond > rewardsPerSecondLimit) {
+        uint256 timeForEmissions = IStaking(instance).timeForEmissions();
+        if (timeForEmissions > timeForEmissionsLimit) {
             return false;
         }
 
@@ -279,36 +312,38 @@ contract StakingVerifier {
     }
 
     /// @dev Changes staking parameter limits.
-    /// @param _rewardsPerSecondLimit Rewards per second limit.
+    /// @param _minStakingDepositLimit Minimum staking deposit limit.
     /// @param _timeForEmissionsLimit Time for emissions limit.
     /// @param _numServicesLimit Limit for the number of services.
+    /// @param _apyLimit APY limit in 1e18 format.
     function changeStakingLimits(
-        uint256 _rewardsPerSecondLimit,
+        uint256 _minStakingDepositLimit,
         uint256 _timeForEmissionsLimit,
-        uint256 _numServicesLimit
+        uint256 _numServicesLimit,
+        uint256 _apyLimit
     ) external {
         // Check the contract ownership
         if (owner != msg.sender) {
             revert OwnerOnly(owner, msg.sender);
         }
 
         // Zero values check
-        if (_rewardsPerSecondLimit == 0 || _timeForEmissionsLimit == 0 || _numServicesLimit == 0) {
+        if (_minStakingDepositLimit == 0 || _timeForEmissionsLimit == 0 || _numServicesLimit == 0 || _apyLimit == 0) {
             revert ZeroValue();
         }
 
-        rewardsPerSecondLimit = _rewardsPerSecondLimit;
         timeForEmissionsLimit = _timeForEmissionsLimit;
         numServicesLimit = _numServicesLimit;
-        emissionsLimit = _rewardsPerSecondLimit * _timeForEmissionsLimit * _numServicesLimit;
+        apyLimit = _apyLimit;
 
-        emit StakingLimitsUpdated(_rewardsPerSecondLimit, _timeForEmissionsLimit, _numServicesLimit, emissionsLimit);
+        emit StakingLimitsUpdated(_minStakingDepositLimit, _timeForEmissionsLimit, _numServicesLimit, _apyLimit);
     }
 
     /// @dev Gets emissions amount limit for a specific staking proxy instance.
-    /// @notice The address field is reserved for the proxy instance, if needed in the next verifier version.
-    /// @return Emissions amount limit.
-    function getEmissionsAmountLimit(address) external view returns (uint256) {
-        return emissionsLimit;
+    /// @param instance Staking proxy instance.
+    /// @return amount Emissions amount limit.
+    function getEmissionsAmountLimit(address instance) external view returns (uint256 amount) {
+        // Get calculated emissions amount from the instance
+        amount = IStaking(instance).emissionsAmount();
     }
 }