done

slownie.go

@@ -1,12 +1,10 @@
-package main
+package slownie
 
 import (
 	"errors"
 	"fmt"
 	"math"
-	"math/rand"
 	"strings"
-	"time"
 )
 
 var _smallNumbers = []string{
@@ -37,9 +35,19 @@ var _zlotyWord = []string{"złoty", "złote", "złotych"}
 
 var _groszyWord = []string{"grosz", "grosze", "groszy"}
 
+func round(num float64) int {
+	return int(num + math.Copysign(0.5, num))
+}
+
+func toFixed(num float64, precision int) float64 {
+	output := math.Pow(10, float64(precision))
+	return float64(round(num*output)) / output
+}
+
 func split(value float64) (int64, int32) {
 	pre := int64(value)
-	post := int32(math.Mod((value*100 + 0.5), 100))
+	// post := int32((value - float64(pre)) * 100)
+	post := int32(math.Mod((value*100)+0.5, 100))
 	return pre, post
 }
 
@@ -116,7 +124,9 @@ func someSlownie(value int64, some []string) string {
 	return slownie(value) + " " + some[caseWord(int(value))]
 }
 
-func kwotaSlownie(input float64) (output string, err error) {
+// KwotaSlownie - return value in words of zloty and groszy
+func KwotaSlownie(input float64) (output string, err error) {
+	input = toFixed(input, 2)
 	defer func() {
 		if r := recover(); r != nil {
 			err = errors.New("too big number")
@@ -128,24 +138,5 @@ func kwotaSlownie(input float64) (output string, err error) {
 		input = -input
 	}
 	zloty, grosze := split(input)
-	return minusword + someSlownie(zloty, _zlotyWord) + fmt.Sprintf(" %d/100", grosze), nil
-}
-
-func main() {
-	r := rand.New(rand.NewSource(time.Now().UnixNano()))
-
-	for i := 0; i < 10; i++ {
-		x := r.Float64() * 10000000000000000
-		if kwota, err := kwotaSlownie(x); err == nil {
-			fmt.Printf("%.2f %s\n", x, kwota)
-		} else {
-			fmt.Printf("%.2f %s\n", x, err)
-		}
-	}
-	x := 4831179.50
-	if kwota, err := kwotaSlownie(x); err == nil {
-		fmt.Printf("%.2f %s\n", x, kwota)
-	} else {
-		fmt.Printf("%.2f %s\n", x, err)
-	}
+	return minusword + someSlownie(zloty, _zlotyWord) + fmt.Sprintf(" %02d/100", grosze), nil
 }