From 84722cb90bc7b50784ca981d9268bfc18b76731c Mon Sep 17 00:00:00 2001
From: thiagodeev <thiagodeev@gmail.com>
Date: Thu, 29 Aug 2024 23:43:58 -0300
Subject: [PATCH] chore: Refactor main.go to pad zeros in felt hex values

---
 examples/deployAccount/main.go |  5 ++---
 examples/internal/setup.go     | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/examples/deployAccount/main.go b/examples/deployAccount/main.go
index 24152bf0..e135825f 100644
--- a/examples/deployAccount/main.go
+++ b/examples/deployAccount/main.go
@@ -77,8 +77,7 @@ func main() {
 	if err != nil {
 		panic(err)
 	}
-	fmt.Println("PrecomputedAddress:", precomputedAddress)
-
+	fmt.Println("PrecomputedAddress:", setup.PadZerosInFelt(precomputedAddress))
 	// Sign the transaction
 	err = accnt.SignDeployAccountTransaction(context.Background(), &tx.DeployAccountTxn, precomputedAddress)
 	if err != nil {
@@ -115,7 +114,7 @@ func main() {
 	// At this point you need to add funds to precomputed address to use it.
 	var input string
 
-	fmt.Println("The `precomputedAddress` account needs to have enough ETH to perform a transaction.")
+	fmt.Println("\nThe `precomputedAddress` account needs to have enough ETH to perform a transaction.")
 	fmt.Printf("Use the starknet faucet to send ETH to your `precomputedAddress`. You need aproximately %f ETH. \n", feeInETH)
 	fmt.Println("When your account has been funded by the faucet, press any key, then `enter` to continue : ")
 	fmt.Scan(&input)
diff --git a/examples/internal/setup.go b/examples/internal/setup.go
index 5342793c..912fee98 100644
--- a/examples/internal/setup.go
+++ b/examples/internal/setup.go
@@ -7,6 +7,7 @@ import (
 	"os"
 	"strconv"
 
+	"github.com/NethermindEth/juno/core/felt"
 	"github.com/NethermindEth/starknet.go/rpc"
 	"github.com/joho/godotenv"
 )
@@ -72,3 +73,23 @@ func getEnv(envName string) string {
 	}
 	return env
 }
+
+// PadZerosInFelt pads zeros to the left of a hex felt value to make it 64 characters long.
+func PadZerosInFelt(hexFelt *felt.Felt) string {
+	length := 66
+	hexStr := hexFelt.String()
+
+	// Check if the hex value is already of the desired length
+	if len(hexStr) >= length {
+		return hexStr
+	}
+
+	// Extract the hex value without the "0x" prefix
+	hexValue := hexStr[2:]
+	// Pad zeros after the "0x" prefix
+	paddedHexValue := fmt.Sprintf("%0*s", length-2, hexValue)
+	// Add back the "0x" prefix to the padded hex value
+	paddedHexStr := "0x" + paddedHexValue
+
+	return paddedHexStr
+}