package docker

import (
	"bytes"
	"os"
	"os/exec"
	"path/filepath"
	"strconv"
	"strings"
)

// Return bytes, inodes occupied by a directory and/or error if there is any
func du(path string) (int, int, error) {
	space, inodes := 0, 0

	// Occupied space
	var out bytes.Buffer
	command := exec.Command("/usr/bin/du -m -s " + path)
	command.Stdout = &out
	err := command.Run()
	if err != nil {
		return space, inodes, err
	}
	fields := strings.Fields(strings.TrimSpace(out.String()))
	out.Reset()

	if len(fields) == 2 {
		space, err = strconv.Atoi(fields[0])
		if err != nil {
			return space, inodes, err
		}
	}

	// Occupied inodes
	command = exec.Command("/usr/bin/du --inodes -s " + path)
	command.Stdout = &out
	err = command.Run()
	if err != nil {
		return space, inodes, err
	}
	fields = strings.Fields(strings.TrimSpace(out.String()))
	out.Reset()

	if len(fields) == 2 {
		space, err = strconv.Atoi(fields[0])
		if err != nil {
			return inodes, inodes, err
		}
	}

	return space, inodes, nil
}

// Removes content of given directory
func removeDirectory(dir string) error {
	d, err := os.Open(dir)
	if err != nil {
		return err
	}
	defer d.Close()
	names, err := d.Readdirnames(-1)
	if err != nil {
		return err
	}
	for _, name := range names {
		err = os.RemoveAll(filepath.Join(dir, name))
		if err != nil {
			return err
		}
	}
	return nil
}