package com.topdraw.security;

import com.alibaba.fastjson.JSONObject;
import com.topdraw.utils.StringUtils;
import lombok.extern.slf4j.Slf4j;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.AlgorithmParameters;
import java.security.Key;
import java.security.Security;
import java.security.spec.AlgorithmParameterSpec;
import java.util.Arrays;

@Slf4j
public class AESUtil {

	public static String encrypt(String data, String key) {
		String strResult = null;
		try {
			SecretKey secretKey = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			AlgorithmParameterSpec aps = new IvParameterSpec("0123456789ABCDEF".getBytes("UTF-8"));
			cipher.init(Cipher.ENCRYPT_MODE, secretKey, aps);
			byte[] result = cipher.doFinal(data.getBytes("UTF-8"));
			StringBuilder sb_hex = new StringBuilder();
			for (byte b : result) {
				sb_hex.append(String.format("%02x", b));
			}
			strResult = sb_hex.toString();
		} catch (Exception e) {

		}
		return strResult;
	}

	public static String decrypt(String encryptedData, String key) {
		String strResult = null;
		try {
			int len = encryptedData.length() / 2;
			byte[] data = new byte[len];
			for (int i = 0; i < len; i++) {
				String str = encryptedData.substring(i * 2, i * 2 + 2);
				data[i] = Integer.valueOf(str, 16).byteValue();
			}
			SecretKey secretKey = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			AlgorithmParameterSpec aps = new IvParameterSpec("0123456789ABCDEF".getBytes("UTF-8"));
			cipher.init(Cipher.DECRYPT_MODE, secretKey, aps);
			byte[] result = cipher.doFinal(data);
			strResult = new String(result, "UTF-8");
		} catch (Exception e) {

		}
		return strResult;
	}

	private static final String AES ="AES";
	private static final String AES_CBC_PKCS7 ="AES/CBC/PKCS7Padding";
	public static String decryptJsUserInfo(String encryptedData,String iv,String sessionKey) {
		try {
			byte[] data = java.util.Base64.getDecoder().decode(encryptedData);
			byte[] aseKey = java.util.Base64.getDecoder().decode(sessionKey);
			byte[] ivData = java.util.Base64.getDecoder().decode(iv);
			Security.addProvider(new BouncyCastleProvider());
			Cipher cipher = Cipher.getInstance(AES_CBC_PKCS7);

			Key sKeySpec = new SecretKeySpec(aseKey, AES);
			AlgorithmParameterSpec aps = new IvParameterSpec(ivData);
			cipher.init(Cipher.DECRYPT_MODE, sKeySpec, aps);// 初始化
			byte[] result = cipher.doFinal(data);
			return new String(result);
		} catch (Exception e) {
			log.error("decryptJsUserInfo："+ e);
			return null;
		}
	}

	public static JSONObject decryptJsUserPhone(String encryptedData, String iv, String key) {
		byte[] dataByte = java.util.Base64.getDecoder().decode(encryptedData);
		// 加密秘钥
		byte[] keyByte = java.util.Base64.getDecoder().decode(key);
		// 偏移量
		byte[] ivByte = java.util.Base64.getDecoder().decode(iv);
		try {
			// 如果密钥不足16位，那么就补足.  这个if 中的内容很重要
			int base = 16;
			if (keyByte.length % base != 0) {
				int groups = keyByte.length / base + (keyByte.length % base != 0 ? 1 : 0);
				byte[] temp = new byte[groups * base];
				Arrays.fill(temp, (byte) 0);
				System.arraycopy(keyByte, 0, temp, 0, keyByte.length);
				keyByte = temp;
			}
			// 初始化
			Security.addProvider(new BouncyCastleProvider());
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding","BC");
			SecretKeySpec spec = new SecretKeySpec(keyByte, "AES");
			AlgorithmParameters parameters = AlgorithmParameters.getInstance("AES");
			parameters.init(new IvParameterSpec(ivByte));
			cipher.init(Cipher.DECRYPT_MODE, spec, parameters);// 初始化
			byte[] resultByte = cipher.doFinal(dataByte);
			if (null != resultByte && resultByte.length > 0) {
				String result = new String(resultByte, "UTF-8");
				return JSONObject.parseObject(result);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}
}