refactor(util.go): improve precision in conversion ratio calculation

internal/oracle/util.go

@@ -2,36 +2,39 @@ package oracle
 
 import (
 	"fmt"
-	"math"
 	"math/big"
 
 	"github.com/dwarvesf/icy-backend/internal/model"
 )
 
+// getConversionRatio calculates the ratio of circulated ICY tokens to BTC supply
+// The ratio is scaled by 10^6 to preserve 6 decimal places of precision
 func getConversionRatio(circulatedIcy, btcSupply *model.Web3BigInt) (*model.Web3BigInt, error) {
 	if circulatedIcy == nil || btcSupply == nil {
 		return nil, fmt.Errorf("circulatedIcy or btcSupply is nil")
 	}
 
-	icyFloat := circulatedIcy.ToFloat()
-	btcFloat := btcSupply.ToFloat()
+	// Convert inputs to big.Float for high-precision calculation
+	icyFloat := new(big.Float).SetFloat64(circulatedIcy.ToFloat())
+	btcFloat := new(big.Float).SetFloat64(btcSupply.ToFloat())
 
-	if btcFloat == 0 {
+	// Handle zero BTC supply case
+	if btcFloat.Cmp(new(big.Float).SetFloat64(0)) == 0 {
 		return &model.Web3BigInt{
 			Value:   "0",
 			Decimal: 6,
 		}, nil
 	}
 
-	ratio := icyFloat / btcFloat
-
-	ratioFloat := new(big.Float).SetFloat64(ratio)
-
-	multiplier := new(big.Float).SetFloat64(math.Pow(10, 6))
-	ratioFloat.Mul(ratioFloat, multiplier)
+	// Calculate ratio and scale by 10^6
+	ratio := new(big.Float).Quo(icyFloat, btcFloat)
+	multiplier := new(big.Float).SetFloat64(1e6)
+	scaledRatio := new(big.Float).Mul(ratio, multiplier)
 
+	// Convert to integer representation
 	ratioInt := new(big.Int)
-	ratioFloat.Int(ratioInt)
+	scaledRatio.Int(ratioInt)
+
 	return &model.Web3BigInt{
 		Value:   ratioInt.String(),
 		Decimal: 6,