package com.hx.util;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;

/**
 * AES加密工具类
 */
public class Aes {

    /**
     * 将二进制转换成16进制
     *
     * @param buf 字节数组
     * @return
     */
    public static String parseByte2HexStr(byte buf[]) {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < buf.length; i++) {
            String hex = Integer.toHexString(buf[i] & 0xFF);
            if (hex.length() == 1) {
                hex = '0' + hex;
            }
            sb.append(hex.toUpperCase());
        }
        return sb.toString();
    }

    /**
     * 将16进制转换为二进制
     *
     * @param hexStr 16进制字符
     * @return
     */
    public static byte[] parseHexStr2Byte(String hexStr) {
        if (hexStr.length() < 1)
            return null;
        byte[] result = new byte[hexStr.length() / 2];
        for (int i = 0; i < hexStr.length() / 2; i++) {
            int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16);
            int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2), 16);
            result[i] = (byte) (high * 16 + low);
        }
        return result;
    }

    /**
     * 加密
     * @param str 待加密字符串
     * @param secret 密钥
     * @return
     */
    public static byte[] encrypt(String str, String secret) {
        if (null != str) {
            byte[] bytes = null;

            try {
                Base64 base64 = new Base64();
                String ALGORITHM = "AES";
                SecretKey desKey = new SecretKeySpec(secret.getBytes("UTF-8"), ALGORITHM);// 生成密钥
                Cipher c;
                c = Cipher.getInstance(ALGORITHM);
                c.init(Cipher.ENCRYPT_MODE, desKey);
                bytes = c.doFinal(str.getBytes("UTF-8"));
                return bytes;
            } catch (Exception e) {
                e.printStackTrace();
            }

        }
        return null;
    }

    /**
     * 解密
     * @param str 待解密字符串
     * @param secret 密钥
     * @return
     */
    public static byte[] decrypt(byte[] str, String secret) {
        try {
            String ALGORITHM = "AES";
            SecretKey desKey = new SecretKeySpec(secret.getBytes("UTF-8"), ALGORITHM);// 生成密钥
            Cipher c = Cipher.getInstance(ALGORITHM);
            c.init(Cipher.DECRYPT_MODE, desKey);
            return c.doFinal(str);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    public static void main(String[] args) throws UnsupportedEncodingException {

        String content = "apiKey=phitabfaceapi&userId=o5W1it6Pvqn6vPX6E1BGERH8J1lw";
        String password = "phitabfacesecret";

        byte[] encode = encrypt(content, password);
        String code = parseByte2HexStr(encode);
        System.out.println("密文字符串：" + code);

        //16进制字符串转成字节数组
        byte[] decode = parseHexStr2Byte(code);
        // 解密
        byte[] decryptResult = decrypt(decode, password);
        System.out.println("解密后：" + new String(decryptResult, "UTF-8")); //不转码会乱码

    }
}