용량 컨버전 로직 추가

misc/converse.go

@@ -2,9 +2,11 @@ package misc
 
 import (
 	"strconv"
+	"fmt"
+	"math"
+	"image"
 )
 
-
 func mustParseInt(value string, bits int) int64 {
 	if parsed, err := strconv.ParseInt(value, 10, bits); err != nil {
 		panic(err)
@@ -124,3 +126,65 @@ func FormatInt16(value int16) string { return strconv.FormatInt(int64(value), 10
 func FormatInt32(value int32) string { return strconv.FormatInt(int64(value), 10) }
 func FormatInt64(value int64) string { return strconv.FormatInt(value, 10) }
 func FormatInt(value int) string     { return strconv.FormatInt(int64(value), 10) }
+
+const (
+	Byte  = 1 << (10 * iota)
+	KiByte
+	MiByte
+	GiByte
+	TiByte
+	PiByte
+	EiByte
+	ZiByte
+	YiByte
+)
+
+var bytesSizeTable = map[string]uint64{
+	"B":   Byte,
+	"KiB": KiByte,
+	"MiB": MiByte,
+	"GiB": GiByte,
+	"TiB": TiByte,
+	"PiB": PiByte,
+	"EiB": EiByte,
+	"ZiB": ZiByte,
+	"YiB": YiByte,
+}
+
+func logn(n, b float64) float64 {
+	return math.Log(n) / math.Log(b)
+}
+
+func humanateBytes(s uint64, base float64, sizes []string) string {
+	if s < 10 {
+		return fmt.Sprintf("%dB", s)
+	}
+	e := math.Floor(logn(float64(s), base))
+	suffix := sizes[int(e)]
+	val := float64(s) / math.Pow(base, math.Floor(e))
+	f := "%.0f"
+	if val < 10 {
+		f = "%.1f"
+	}
+
+	return fmt.Sprintf(f+"%s", val, suffix)
+}
+
+// FileSize calculates the file size and generate user-friendly string.
+func FileSize(s uint64) string {
+	sizes := []string{"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"}
+	return humanateBytes(s, 1024, sizes)
+}
+
+func AspectRatio(srcRect image.Point, toResize uint64) image.Point {
+	w, h := int(toResize), getRatioSize(int(toResize), srcRect.Y, srcRect.X)
+	if srcRect.X < srcRect.Y {
+		w, h = getRatioSize(int(toResize), srcRect.X, srcRect.Y), int(toResize)
+	}
+	return image.Point{w, h}
+}
+
+func getRatioSize(a, b, c int) int {
+	d := a * b / c
+	return (d + 1) & -1
+}