package com.hb.proj.gather.utils;

import java.util.ArrayList;
import java.util.List;

public class Crc16Utils {

	/**
     * 一个字节包含位的数量 8
     */
    private static final int BITS_OF_BYTE = 8;

    /**
     * 多项式
     */
    private static final int POLYNOMIAL = 0xA001;

    /**
     * 初始值
     */
    private static final int INITIAL_VALUE = 0xFFFF;

    /**
     * CRC16 编码
     * @param bytes 编码内容
     * @return 编码结果
     */
    public static String crc16(int[] bytes) {
        int res = INITIAL_VALUE;
        for (int data : bytes) {
            res = res ^ data;
            for (int i = 0; i < BITS_OF_BYTE; i++) {
                res = (res & 0x0001) == 1 ? (res >> 1) ^ POLYNOMIAL : res >> 1;
            }
        }
        return Integer.toHexString(revert(res));
    }

    /**
     * 翻转16位的高八位和低八位字节  低位在前  LH
     * @param src 翻转数字
     * @return 翻转结果
     */
    private static int revert(int src) {
        int lowByte = (src & 0xFF00) >> 8;
        int highByte = (src & 0x00FF) << 8;
        return lowByte | highByte;
    }

   
    
    
    public static int getCRC(byte[] bytes) {
    	int CRC = 0x0000ffff;
        int POLYNOMIAL = 0x0000a001;
        
        for(byte b : bytes) {
        	CRC = CRC ^ (b & 0x000000ff) ;
        	for(int j = 0; j < 8; j++) {
        		CRC = (CRC & 0x0001) == 1 ? (CRC >> 1) ^ POLYNOMIAL : CRC >> 1;
        	}
        }
        return revert(CRC);
    }


    public static void main(String[] args) {
       // int[] data = new int[]{0x01, 0x03, 0x03, 0xd7, 0x00, 0x01};
       // System.out.println(Crc16Utils.crc16(data));
    	String[] addrs= {"1810","188D","190A","1987","1A04","1A81","1AFE","1B7B","1BF8","1C75","1CF2","1D6F","1DEC","1E69","1EE6","1F63","1FE0","205D","20DA","2157","21D4","2251","22CE","234B","23C8","2445","24C2","253F","25BC","2639","26B6","2733","27B0","282D","28AA","2927","29A4","2A21","2A9E","2B1B"};
        int[]  cmds=null;
        int ad1=0,ad2=0;
        String s1,s2=null,crc=null;
        String cmdstr=null;
    	for(String adr : addrs) {
    		
    		ad1=Integer.parseInt(adr.substring(0,2),16);
    		ad2=Integer.parseInt(adr.substring(2,4),16);
    		cmds=new int[] {0x01,0x03,ad1,ad2,0x00,0x7d};
    		crc=Crc16Utils.crc16(cmds);
    		
    		
    		System.out.println(crc);
    		
    		s1=(ad1>0x7f?"(byte)0x":"0x")+adr.substring(0,2);
    		s2=(ad2>0x7f?"(byte)0x":"0x")+adr.substring(2,4);
    		
    		cmdstr="0x01,0x03,"+s1+","+s2+",0x00,0x7d";
    		
    		if(crc.length()>3) {
    			ad1=Integer.parseInt(crc.substring(0,2),16);
        		ad2=Integer.parseInt(crc.substring(2,4),16);
        		
        		s1=(ad1>0x7f?"(byte)0x":"0x")+crc.substring(0,2);
        		s2=(ad2>0x7f?"(byte)0x":"0x")+crc.substring(2,4);
        		
        		cmdstr+=","+s1+","+s2;
    		}
    		
    		
    		System.out.println(cmdstr);
    	}
       
       // System.out.println(Integer.toHexString(Crc16Utils.getCRC(data2)));
    }
}