refactor all container widgets into subpackage

cwidgets/util.go

@@ -0,0 +1,60 @@
+package cwidgets
+
+import (
+	"fmt"
+	"strconv"
+
+	ui "github.com/gizak/termui"
+)
+
+const (
+	kb = 1024
+	mb = kb * 1024
+	gb = mb * 1024
+)
+
+// convenience method
+func ByteFormatInt(n int) string {
+	return ByteFormat(int64(n))
+}
+
+func ByteFormat(n int64) string {
+	if n < kb {
+		return fmt.Sprintf("%sB", strconv.FormatInt(n, 10))
+	}
+	if n < mb {
+		n = n / kb
+		return fmt.Sprintf("%sK", strconv.FormatInt(n, 10))
+	}
+	if n < gb {
+		n = n / mb
+		return fmt.Sprintf("%sM", strconv.FormatInt(n, 10))
+	}
+	nf := float64(n) / gb
+	return fmt.Sprintf("%sG", unpadFloat(nf))
+}
+
+func unpadFloat(f float64) string {
+	return strconv.FormatFloat(f, 'f', getPrecision(f), 64)
+}
+
+func getPrecision(f float64) int {
+	frac := int((f - float64(int(f))) * 100)
+	if frac == 0 {
+		return 0
+	}
+	if frac%10 == 0 {
+		return 1
+	}
+	return 2 // default precision
+}
+
+func ColorScale(n int) ui.Attribute {
+	if n > 70 {
+		return ui.ColorRed
+	}
+	if n > 30 {
+		return ui.ColorYellow
+	}
+	return ui.ColorGreen
+}