package util

import (
    "io"
    "math/rand"
    "os"
    "path/filepath"
    "time"

    //   "strings"
)


func DirModTime (path string) (time.Time, error) {

    var lastTime time.Time
    err := filepath.Walk(path, func(path string, info os.FileInfo, err error) error {
        if err != nil {
            return err
        }

        cur := info.ModTime()
        if cur.After(lastTime) {
            lastTime = info.ModTime()
        }

        return nil
    })
    if err != nil {
        return time.Time{}, err
    }
    return lastTime, nil
}

func RandomString(n int) string {
    var letter = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")

    b := make([]rune, n)
    for i := range b {
        b[i] = letter[rand.Intn(len(letter))]
    }
    return string(b)
}

func CopyFile(source string, dest string) error {
    sourceFD, err := os.Open(source)
    if err != nil {
        return err
    }

    finfo, err := sourceFD.Stat()

    destFD, err := os.OpenFile(dest, os.O_RDWR|os.O_CREATE, finfo.Mode())
    if err != nil {
        return err
    }

    _, err = io.Copy(destFD, sourceFD)
    if err != nil {
        return err
    }

    sourceFD.Close()

    return destFD.Close()
}