sort

package main

import (
	"flag"
	"fmt"
	"os"
	"path/filepath"
	"sort"
	"strconv"
	"strings"
)

var (
	dir      string
	split    string
	index    int
	suffix   string
	fullpath bool
)

func init() {
	flag.StringVar(&dir, "d", "./", `-d ./ 指定排序的文件目录`)
	flag.StringVar(&split, "S", ".", `-S "." 指定分隔符`)
	flag.IntVar(&index, "i", 0, "-i 0 指定使用哪一列进行排序")
	flag.StringVar(&suffix, "s", "", `-s ".sql" 指定排序文件的后缀`)
	flag.BoolVar(&fullpath, "p", false, "-p true 是否打印完整路径")
	flag.Parse()
}

func main() {
	path, err := os.Open(dir)
	if err != nil {
		fmt.Println(err)
		return
	}
	defer path.Close()
	info, err := path.Stat()
	if err != nil {
		fmt.Println(err)
		return
	}
	if !info.IsDir() {
		fmt.Println("指定的路径必须是文件目录")
		return
	}

	files, err := path.Readdir(-1)
	if err != nil {
		fmt.Println(err)
		return
	}
	var list = make(byName, 0, len(files))
	for _, name := range files {
		if !strings.HasSuffix(name.Name(), suffix) {
			continue
		}
		list = append(list, name.Name())
	}
	sort.Sort(list)
	basedir := filepath.Dir(dir)
	for _, path := range list {
		if fullpath {
			fmt.Println(basedir + string(filepath.Separator) + path)
		} else {
			fmt.Println(path)
		}
	}
}

type byName []string

func (f byName) Len() int { return len(f) }

func (f byName) Less(i, j int) bool {
	list := strings.Split(f[i], split)
	if index > len(list)-1 {
		return false
	}
	a := list[index]
	list = strings.Split(f[j], split)
	if index > len(list)-1 {
		return false
	}
	b := list[index]
	aint, err := strconv.Atoi(a)
	if err != nil {
		return a < b
	}
	bint, err := strconv.Atoi(b)
	if err != nil {
		return a < b
	}
	return aint < bint
}

func (f byName) Swap(i, j int) { f[i], f[j] = f[j], f[i] }