fix: incorporate not being selected during the chosen depth

packages/extension-polkagate/src/hooks/useValidatorApy.ts

@@ -10,6 +10,11 @@ import { useCallback, useEffect, useState } from 'react';
 
 import { BN, BN_HUNDRED, BN_ZERO } from '@polkadot/util';
 
+interface ValidatorEraInfo {
+  netReward: BN;
+  total: BN;
+}
+
 export default function useValidatorApy (api: ApiPromise | undefined, validatorAddress: string, isElected?: boolean): string | undefined | null {
   const [apy, setApy] = useState<string | null>();
 
@@ -20,27 +25,25 @@ export default function useValidatorApy (api: ApiPromise | undefined, validatorA
 
     // Define the number of past eras you want to check (e.g., last 10 eras)
     const eraDepth = 10;
-    let depth = 0;
-    let totalDepth = 0;
     const decimal = new BN(10 ** api.registry.chainDecimals[0]);
     let totalRewards = BN_ZERO;
     let totalPoints = BN_ZERO;
     let validatorPoints = BN_ZERO;
     let totalStaked = BN_ZERO;
+    const validatorEraInfo: ValidatorEraInfo[] = [];
 
     const currentEra = ((await api.query['staking']['activeEra']()) as Option<PalletStakingActiveEraInfo>).unwrap().index.toNumber();
     const { commission } = await api.query['staking']['validators'](validatorAddress) as PalletStakingValidatorPrefs;
 
     // Loop over the past eras to calculate rewards for the validator
     for (let eraIndex = currentEra - eraDepth; eraIndex <= currentEra; eraIndex++) {
+      let netReward;
       const eraReward = await api.query['staking']['erasValidatorReward'](eraIndex) as Option<u128>;
 
       if (eraReward.isNone) {
         continue;
       }
 
-      depth++;
-
       const eraPoints = await api.query['staking']['erasRewardPoints'](eraIndex) as PalletStakingEraRewardPoints;
 
       let validatorEraPoints;
@@ -58,7 +61,9 @@ export default function useValidatorApy (api: ApiPromise | undefined, validatorA
         totalPoints = totalPoints.add(eraPoints.total);
         const _eraReward = eraReward.unwrap();
 
-        totalRewards = totalRewards.add(_eraReward.mul(validatorPoints).div(totalPoints).muln(100 - (commission.toNumber() / 1e7)).div(BN_HUNDRED));
+        netReward = _eraReward.mul(validatorPoints).div(totalPoints).muln(100 - (commission.toNumber() / 1e7)).div(BN_HUNDRED);
+      } else {
+        continue;
       }
 
       // Fetch the validator's stake in this era
@@ -72,29 +77,50 @@ export default function useValidatorApy (api: ApiPromise | undefined, validatorA
           continue;
         }
 
-        totalDepth++;
-        totalStaked = totalStaked.add(totalAsBN);
+        validatorEraInfo.push(
+          {
+            netReward,
+            total: totalAsBN
+          });
       }
     }
 
-    // Average the total staked amount over the eras
-    totalStaked = totalStaked.div(decimal).divn(totalDepth);
+    if (!validatorEraInfo.length) {
+      setApy(null);
+    }
+
+    validatorEraInfo.forEach(({ netReward, total }) => {
+      totalRewards = totalRewards.add(netReward);
+      totalStaked = totalStaked.add(total);
+    });
 
-    const dailyReward = totalRewards.div(decimal).divn(depth);
+    const actualDepth = validatorEraInfo.length;
+
+    totalStaked = totalStaked.div(decimal).divn(actualDepth);
+
+    const dailyReward = totalRewards.div(decimal).divn(actualDepth);
 
     // Calculate daily return as a fraction of the staked amount
     const dailyReturn = dailyReward.toNumber() / totalStaked.toNumber();
 
     const APY = (dailyReturn * 365 * 100).toFixed(2);
 
+    if (!isFinite(+APY) || isNaN(+APY)) {
+      setApy(null);
+    }
+
     setApy(APY);
   }, [api]);
 
   useEffect(() => {
-    if (!api || !isElected) {
+    if (!api || isElected === undefined) {
       return;
     }
 
+    if (isElected === false) {
+      return setApy(null);
+    }
+
     calculateValidatorAPY(validatorAddress).catch(console.error);
   }, [api, calculateValidatorAPY, isElected, validatorAddress]);