update remaining reward calc method

x/liquidstaking/keeper/net_amount.go

@@ -55,11 +55,20 @@ func (k Keeper) GetNetAmountState(ctx sdk.Context) (nas types.NetAmountState) {
 			cachedCtx, _ := ctx.CacheContext()
 			endingPeriod := k.distributionKeeper.IncrementValidatorPeriod(cachedCtx, validator)
 			delRewards := k.distributionKeeper.CalculateDelegationRewards(cachedCtx, validator, delegation, endingPeriod)
+			// chunk's remaining reward is calculated by
+			// 1. rest = del_reward - insurance_commission
+			// 2. remaining = rest x (1 - module_fee_rate)
+			// 3. result = remaining x (1 - discount_rate)
 			delReward := delRewards.AmountOf(bondDenom)
 			insuranceCommission := delReward.Mul(pairedIns.FeeRate)
-			// insuranceCommission is not reward of module
-			pureReward := delReward.Sub(insuranceCommission)
-			totalRemainingRewards = totalRemainingRewards.Add(pureReward)
+			restReward := delReward.Sub(insuranceCommission)
+			moduleFeeRate, _ := k.CalcDynamicFeeRate(ctx)
+			remainingReward := restReward.Mul(sdk.OneDec().Sub(moduleFeeRate))
+			totalRemainingRewards = totalRemainingRewards.Add(
+				remainingReward.Mul(
+					sdk.OneDec().Sub(k.CalcDiscountRate(ctx)),
+				),
+			)
 		default:
 			k.stakingKeeper.IterateDelegatorUnbondingDelegations(ctx, chunk.DerivedAddress(), func(ubd stakingtypes.UnbondingDelegation) (stop bool) {
 				for _, entry := range ubd.Entries {

x/liquidstaking/keeper/net_amount_test.go

@@ -0,0 +1,42 @@
+package keeper_test
+
+import (
+	"github.com/Canto-Network/Canto/v6/x/liquidstaking/types"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+func (suite *KeeperTestSuite) TestGetNetAmountState() {
+	env := suite.setupLiquidStakeTestingEnv(testingEnvOptions{
+		desc:                  "",
+		numVals:               3,
+		fixedValFeeRate:       TenPercentFeeRate,
+		valFeeRates:           nil,
+		fixedPower:            1,
+		powers:                nil,
+		numInsurances:         3,
+		fixedInsuranceFeeRate: TenPercentFeeRate,
+		insuranceFeeRates:     nil,
+		numPairedChunks:       3,
+		fundingAccountBalance: types.ChunkSize.MulRaw(40),
+	})
+
+	suite.ctx = suite.advanceHeight(suite.ctx, 100, "delegation rewards are accumulated")
+	nas := suite.app.LiquidStakingKeeper.GetNetAmountState(suite.ctx)
+
+	cachedCtx, _ := suite.ctx.CacheContext()
+	suite.app.DistrKeeper.WithdrawDelegationRewards(cachedCtx, env.pairedChunks[0].DerivedAddress(), env.insurances[0].GetValidator())
+	delReward := suite.app.BankKeeper.GetBalance(cachedCtx, env.pairedChunks[0].DerivedAddress(), suite.denom)
+	totalDelReward := delReward.Amount.MulRaw(int64(len(env.pairedChunks)))
+	suite.Equal("8999964000143999250000", totalDelReward.String())
+
+	// Calc TotalRemainingRewards manually
+	rest := totalDelReward.ToDec().Mul(sdk.OneDec().Sub(TenPercentFeeRate))
+	remaining := rest.Mul(sdk.OneDec().Sub(nas.FeeRate))
+	result := remaining.Mul(sdk.OneDec().Sub(nas.DiscountRate))
+	suite.Equal("7595237306532985264014.570227833838100000", result.String())
+	suite.Equal(result.String(), nas.TotalRemainingRewards.String())
+	suite.True(
+		totalDelReward.GT(nas.TotalRemainingRewards.TruncateInt()),
+		"total del reward should be greater than total remaining rewards",
+	)
+}