package etelligens.com.foodsafety.utils;

import java.math.BigInteger;
import java.nio.ByteBuffer;

/**
 * @author wj
 * @Description: 获取硬件中的指令加密
 * @create 2023/12/27  14:53
 **/
public class hardwareEncryption {

    public static  byte[] CRC16_XMODEM(byte[] data,int type){
        int len = data.length;
        int wCRCin = 0x0000;
        int wCPoly = 0x0483;
        int i,j;
        if(type == 1)
        {
            wCPoly = 0x6072;
        }
        for(i=0;i<len;i++)
        {
            wCRCin = wCRCin^(data[i]<<8);
            for(j=0;j<8;j++)
            {
                if((wCRCin & 0x8000)>0) wCRCin = (wCRCin<<1)^wCPoly;
                else wCRCin = wCRCin<<1;
            }
        }
        return intToByteArray(wCRCin & 0x0000ffff);
    }

    public static byte[] intToByteArray(int value) {
        return ByteBuffer.allocate(4).putInt(value).array();
    }

    public static byte[] intTo8DigitHexString(int decimalNumber) {
        // 使用 Integer.toHexString() 将整数转为十六进制字符串
        String hexString = Integer.toHexString(decimalNumber);

        // 如果十六进制字符串长度不足8位，前面补0
        while (hexString.length() < 8) {
            hexString = "0" + hexString;
        }

        return hexStringToByteArray(hexString);
    }
    private static byte[] hexStringToByteArray(String hexString) {
        // 确保字符串长度为偶数
        if (hexString.length() % 2 != 0) {
            throw new IllegalArgumentException("Hex string length must be even.");
        }

        // 计算字节数组的长度
        int byteArrayLength = hexString.length() / 2;
        byte[] byteArray = new byte[byteArrayLength];

        // 解析每两个字符为一个字节
        for (int i = 0; i < byteArrayLength; i++) {
            int index = i * 2;
            int intValue = Integer.parseInt(hexString.substring(index, index + 2), 16);
            byteArray[i] = (byte) intValue;
        }

        return byteArray;
    }

    public static byte[] concatenateArrays(byte[] first, byte[] second) {
        ByteBuffer buffer = ByteBuffer.allocate(first.length + second.length);
        buffer.put(first);
        buffer.put(second);
        return buffer.array();
    }
    public static byte[] removeFirstAndLast(byte[] originalArray) {
        if (originalArray.length < 3) {
            // 如果数组长度小于3，无法去掉第一个和最后一个元素
            return new byte[0];
        }

        byte[] newArray = new byte[originalArray.length - 2];
        System.arraycopy(originalArray, 1, newArray, 0, newArray.length);

        return newArray;
    }

    public static byte[] removeFirstTwo(byte[] originalArray) {
        if (originalArray.length < 2) {
            // 如果数组长度小于3，无法去掉第一个和第二个元素
            return new byte[0];
        }

        byte[] newArray = new byte[originalArray.length - 2];
        System.arraycopy(originalArray, 2, newArray, 0, newArray.length);

        return newArray;
    }

 }