package aes

import (
	"errors"
	"fmt"
	"io"
	"os"

	"b612.me/starcrypto"
	"b612.me/staros"
)

func EncodeStr(str string, key []byte) (string, error) {
	if len(key) < 16 {
		key = starcrypto.Md5(key)
	} else {
		key = key[:len(key)/16*16]
		if len(key) > 32 {
			key = key[:32]
		}
	}
	ensdata, err := starcrypto.CustomEncryptAesCFB([]byte(str), key)
	if err != nil {
		return "", err
	}
	return starcrypto.Base64Encode(ensdata), nil
}

func DecodeStr(str string, key []byte) (string, error) {
	if len(key) < 16 {
		key = starcrypto.Md5(key)
	} else {
		key = key[:len(key)/16*16]
	}
	strtmp, err := starcrypto.Base64Decode(str)
	if err != nil {
		return "", err
	}
	p, err := starcrypto.CustomDecryptAesCFB(strtmp, key)
	return string(p), err
}

func EncodeFile(fpath, out string, key []byte) error {
	if len(key) < 16 {
		key = starcrypto.Md5(key)
	} else {
		key = key[:len(key)/16*16]
	}
	if !staros.Exists(fpath) {
		return errors.New("SrcFile Not Exists")
	}
	fpsrc, err := os.Open(fpath)
	if err != nil {
		return err
	}
	defer fpsrc.Close()
	fpdst, err := os.Create(out)
	if err != nil {
		return err
	}
	defer fpdst.Close()
	bufsize := 1024 * 1024 //1MB
	stat, _ := fpsrc.Stat()
	buf := make([]byte, bufsize)
	var sumAll int64
	for {
		n, err := fpsrc.Read(buf)
		if err != nil && err != io.EOF {
			return err
		}
		fmt.Printf("已完成：%.2f%%\r", float64(sumAll)/float64(stat.Size())*100)
		sumAll += int64(n)
		if n > 0 {
			encodeBytes, err := starcrypto.CustomEncryptAesCFBNoBlock(buf[:n], key, key)
			if err != nil {
				return err
			}
			fpdst.Write(encodeBytes)
		}
		if err == io.EOF {
			fmt.Print("已完成：100%   \n")
			break
		}
	}
	return nil
}

func DecodeFile(fpath, out string, key []byte) error {
	if len(key) < 16 {
		key = starcrypto.Md5(key)
	} else {
		key = key[:len(key)/16*16]
	}
	if !staros.Exists(fpath) {
		return errors.New("SrcFile Not Exists")
	}
	fpsrc, err := os.Open(fpath)
	if err != nil {
		return err
	}
	defer fpsrc.Close()
	fpdst, err := os.Create(out)
	if err != nil {
		return err
	}
	defer fpdst.Close()
	bufsize := 1024 * 1024 //1MB
	stat, _ := fpsrc.Stat()
	buf := make([]byte, bufsize)
	var sumAll int64
	for {
		n, err := fpsrc.Read(buf)
		if err != nil && err != io.EOF {
			return err
		}
		fmt.Printf("已完成：%.2f%%\r", float64(sumAll)/float64(stat.Size())*100)
		sumAll += int64(n)
		if n > 0 {
			encodeBytes, err := starcrypto.CustomDecryptAesCFBNoBlock(buf[:n], key, key)
			if err != nil {
				return err
			}
			fpdst.Write(encodeBytes)
		}
		if err == io.EOF {
			fmt.Print("已完成：100%   \n")
			break
		}
	}
	return nil
}