package main

import (
	"crypto/md5"
	"crypto/sha1"
	"flag"
	"fmt"
	"github.com/oylshe1314/framework/util"
	"golang.org/x/crypto/md4"
	"golang.org/x/crypto/sha3"
	"hash"
	"os"
	"strings"
)

type strAry []string

func (this *strAry) Set(str string) error {
	*this = append(*this, str)
	return nil
}

func (this *strAry) String() string {
	return strings.Join(*this, " ")
}

const usage = `The hash calculator usage:
Options:
    -a 
     A string to specify the algorithm of the hash value calculating(Case insensitive).
     Provided algorithms include MD4/MD5/SHA1/SHA224/SHA256/SHA384/SHA512, default algorithms MD5.

    -s
     Specicy a string that you want to calculate the hash value.

    -f
     A string to specify the path of the file that you want to calculate the hash value.

    -d
     A string to specify a directory, The calculator will be calculated the hash value of all files in the directory specified.
	
    -i
     Specify if output the information for calculating hash valule

    -m
     Specify if merge all strings, files specified, and files in directories specified to calculate a final hash value.
     The s/f/d options could be specified multiple and used with other options at the same time.
`

func main() {

	var algo string
	var strs strAry
	var dirs strAry
	var files strAry

	var info bool
	var merge bool

	flag.StringVar(&algo, "a", "", "")
	flag.Var(&strs, "s", "")
	flag.Var(&dirs, "d", "")
	flag.Var(&files, "f", "")
	flag.BoolVar(&info, "i", false, "")
	flag.BoolVar(&merge, "m", false, "")

	flag.Usage = func() {
		fmt.Print(usage)
	}

	flag.Parse()

	if len(strs) == 0 && len(files) == 0 && len(dirs) == 0 {
		flag.Usage()
		return
	}

	var h hash.Hash
	if algo == "" {
		algo = "md5"
	} else {
		algo = strings.ToLower(algo)
	}

	switch algo {
	case "md4":
		h = md4.New()
	case "md5":
		h = md5.New()
	case "sha1":
		h = sha1.New()
	case "sha224":
		h = sha3.New224()
	case "sha256":
		h = sha3.New256()
	case "sha384":
		h = sha3.New384()
	case "sha512":
		h = sha3.New512()
	default:
		fmt.Println("Unsupported hash algorithm")
		os.Exit(1)
		return
	}

	var hashs, infos, err = util.HashAll(h, merge, strs, dirs, files)
	if err != nil {
		fmt.Println(err)
		os.Exit(1)
		return
	}

	if !info {
		for i := range hashs {
			fmt.Println(hashs[i])
		}
	} else {
		for i := range hashs {
			fmt.Println(hashs[i], infos[i])
		}
	}
}