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// Copyright 2017 The Gogs Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package tool
import (
"fmt"
"math"
"net/http"
"strings"
)
// IsTextFile returns true if file content format is plain text or empty.
func IsTextFile(data []byte) bool {
if len(data) == 0 {
return true
}
return strings.Contains(http.DetectContentType(data), "text/")
}
func IsImageFile(data []byte) bool {
return strings.Contains(http.DetectContentType(data), "image/")
}
func IsPDFFile(data []byte) bool {
return strings.Contains(http.DetectContentType(data), "application/pdf")
}
func IsVideoFile(data []byte) bool {
return strings.Contains(http.DetectContentType(data), "video/")
}
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("%d B", 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 int64) string {
sizes := []string{"B", "KB", "MB", "GB", "TB", "PB", "EB"}
return humanateBytes(uint64(s), 1024, sizes)
}
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