Add example reward calculator usage (#3171)

vms/platformvm/reward/example_test.go

@@ -0,0 +1,43 @@
+// Copyright (C) 2019-2024, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+package reward
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/ava-labs/avalanchego/utils/units"
+)
+
+func ExampleNewCalculator() {
+	const (
+		day             = 24 * time.Hour
+		week            = 7 * day
+		stakingDuration = 4 * week
+
+		stakeAmount = 100_000 * units.Avax // 100k AVAX
+
+		// The current supply can be fetched with the platform.getCurrentSupply API
+		currentSupply = 447_903_489_576_595_361 * units.NanoAvax // ~448m AVAX
+	)
+	var (
+		mainnetRewardConfig = Config{
+			MaxConsumptionRate: .12 * PercentDenominator,
+			MinConsumptionRate: .10 * PercentDenominator,
+			MintingPeriod:      365 * 24 * time.Hour,
+			SupplyCap:          720 * units.MegaAvax,
+		}
+		mainnetCalculator = NewCalculator(mainnetRewardConfig)
+	)
+
+	potentialReward := mainnetCalculator.Calculate(stakingDuration, stakeAmount, currentSupply)
+
+	fmt.Printf("Staking %d nAVAX for %s with the current supply of %d nAVAX would have a potential reward of %d nAVAX",
+		stakeAmount,
+		stakingDuration,
+		currentSupply,
+		potentialReward,
+	)
+	// Output: Staking 100000000000000 nAVAX for 672h0m0s with the current supply of 447903489576595361 nAVAX would have a potential reward of 473168956104 nAVAX
+}