From 471b7b2f16dc97e57e1b7d317291bb1345c5e1d3 Mon Sep 17 00:00:00 2001
From: coderofstuff <114628839+coderofstuff@users.noreply.github.com>
Date: Fri, 22 Sep 2023 08:45:26 -0600
Subject: [PATCH] Fix off by small amounts in sent amount kaspa

Floating point math causes inconsistencies when converting kas to sompi.

Use a method that parses the amount as a string, the converts it to
sompi then parse back to uint64
---
 cmd/kaspawallet/send.go      | 16 ++++++++++++++--
 cmd/kaspawallet/send_test.go | 25 +++++++++++++++++++++++++
 2 files changed, 39 insertions(+), 2 deletions(-)
 create mode 100644 cmd/kaspawallet/send_test.go

diff --git a/cmd/kaspawallet/send.go b/cmd/kaspawallet/send.go
index 3e20c2b97..71d6fdb24 100644
--- a/cmd/kaspawallet/send.go
+++ b/cmd/kaspawallet/send.go
@@ -4,13 +4,13 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"strconv"
 	"strings"
 
 	"github.com/kaspanet/kaspad/cmd/kaspawallet/daemon/client"
 	"github.com/kaspanet/kaspad/cmd/kaspawallet/daemon/pb"
 	"github.com/kaspanet/kaspad/cmd/kaspawallet/keys"
 	"github.com/kaspanet/kaspad/cmd/kaspawallet/libkaspawallet"
-	"github.com/kaspanet/kaspad/domain/consensus/utils/constants"
 	"github.com/pkg/errors"
 )
 
@@ -35,7 +35,7 @@ func send(conf *sendConfig) error {
 
 	var sendAmountSompi uint64
 	if !conf.IsSendAll {
-		sendAmountSompi = uint64(conf.SendAmount * constants.SompiPerKaspa)
+		sendAmountSompi = kasToSompi(conf.SendAmount)
 	}
 
 	createUnsignedTransactionsResponse, err :=
@@ -99,3 +99,15 @@ func send(conf *sendConfig) error {
 
 	return nil
 }
+
+/**
+ */
+func kasToSompi(amount float64) uint64 {
+	amountInStr := fmt.Sprintf("%.8f", amount)
+
+	parts := strings.Split(amountInStr, ".")
+
+	convertedAmount, _ := strconv.ParseUint(strings.Join(parts, ""), 10, 64)
+
+	return convertedAmount
+}
diff --git a/cmd/kaspawallet/send_test.go b/cmd/kaspawallet/send_test.go
new file mode 100644
index 000000000..dcd04b4e0
--- /dev/null
+++ b/cmd/kaspawallet/send_test.go
@@ -0,0 +1,25 @@
+package main
+
+import "testing"
+
+func TestKasToSompi(t *testing.T) {
+	type testVector struct {
+		originalAmount  float64
+		convertedAmount uint64
+	}
+
+	testVectors := []testVector{
+		{originalAmount: 0, convertedAmount: 0},
+		{originalAmount: 1, convertedAmount: 100000000},
+		{originalAmount: 33184.1489732, convertedAmount: 3318414897320},
+		{originalAmount: 21.35808032, convertedAmount: 2135808032},
+		{originalAmount: 184467440737.09551615, convertedAmount: 18446744073709551615},
+	}
+
+	for _, currentTestVector := range testVectors {
+		if kasToSompi(currentTestVector.originalAmount) != currentTestVector.convertedAmount {
+			t.Fail()
+			t.Logf("Expected %.8f, to convert to %d. Got: %d", currentTestVector.originalAmount, currentTestVector.convertedAmount, kasToSompi(currentTestVector.originalAmount))
+		}
+	}
+}