#include "encryptionIdentify.h"

#define ROTLEFT(a,b)                (((a) << (b)) | ((a) >> (32-(b))))
#define ROTRIGHT(a,b)               (((a) >> (b)) | ((a) << (32-(b))))

#define CH(x,y,z)                   (((x) & (y)) ^ (~(x) & (z)))
#define MAJ(x,y,z)                  (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
#define EP0(x)                      (ROTRIGHT(x,2) ^ ROTRIGHT(x,13) ^ ROTRIGHT(x,22))
#define EP1(x)                      (ROTRIGHT(x,6) ^ ROTRIGHT(x,11) ^ ROTRIGHT(x,25))
#define SIG0(x)                     (ROTRIGHT(x,7) ^ ROTRIGHT(x,18) ^ ((x) >> 3))
#define SIG1(x)                     (ROTRIGHT(x,17) ^ ROTRIGHT(x,19) ^ ((x) >> 10))

static const WORD k[64] = {
	0x428a2f98,0x71374491,0xb5c0fbcf,0xe9b5dba5,0x3956c25b,0x59f111f1,0x923f82a4,0xab1c5ed5,
	0xd807aa98,0x12835b01,0x243185be,0x550c7dc3,0x72be5d74,0x80deb1fe,0x9bdc06a7,0xc19bf174,
	0xe49b69c1,0xefbe4786,0x0fc19dc6,0x240ca1cc,0x2de92c6f,0x4a7484aa,0x5cb0a9dc,0x76f988da,
	0x983e5152,0xa831c66d,0xb00327c8,0xbf597fc7,0xc6e00bf3,0xd5a79147,0x06ca6351,0x14292967,
	0x27b70a85,0x2e1b2138,0x4d2c6dfc,0x53380d13,0x650a7354,0x766a0abb,0x81c2c92e,0x92722c85,
	0xa2bfe8a1,0xa81a664b,0xc24b8b70,0xc76c51a3,0xd192e819,0xd6990624,0xf40e3585,0x106aa070,
	0x19a4c116,0x1e376c08,0x2748774c,0x34b0bcb5,0x391c0cb3,0x4ed8aa4a,0x5b9cca4f,0x682e6ff3,
	0x748f82ee,0x78a5636f,0x84c87814,0x8cc70208,0x90befffa,0xa4506ceb,0xbef9a3f7,0xc67178f2
};

EncryptionIdentify::EncryptionIdentify(){}

/**
 * @brief Construct a new EncryptionIdentify:: EncryptionIdentify object
 * 
 */
EncryptionIdentify::EncryptionIdentify(std::string cryptFilePath)/*: filePath("../resource/encryp_map/cryp_map.txt")*/
{
    filePath = cryptFilePath;
}

/**
 * @brief Destroy the EncryptionIdentify:: EncryptionIdentify object
 * 
 */
EncryptionIdentify::~EncryptionIdentify()
{
    if(ctx != nullptr)
    {
        delete ctx;
        ctx = nullptr;
    }
}

int EncryptionIdentify::init()
{
    if(readEncryptMapValue() < 0) return -1;
    return 0;
}

int EncryptionIdentify::readEncryptMapValue()
{
    std::fstream inFile(filePath);
    inFile.open(filePath, std::ios::in | std::ios::out);
    if(!inFile.is_open())
    {
        std::cout << "encryptionFile open failed!" << std::endl;
        return -1;
    }
    else
    {
        std::string dataLine;
        std::vector<std::string> temStr;
        int i = 0;
        while(std::getline(inFile, dataLine))
        {
            std::cout << "source-dataLine: " << dataLine.size() << std::endl;
            // std::cout << "source-dataLine: " << std::endl;
            // std::cout << dataLine << std::endl;
            dataLine = dataLine.substr(0, dataLine.size()-1);
            std::cout << "substr-dataLine: " << dataLine.size() << std::endl;
            // std::cout << "substr-dataLine: " << std::endl;
            // std::cout << dataLine << std::endl;
            
            temStr = split(dataLine, ",");

            for(int j = 0; j < 256; j++)
            {
                A[i][j] = (unsigned short)std::stoi(temStr.at(j));
            }

            i++;
        }

        // 打印输出A[256][256]中的R值
        // for(int i = 0; i < 256; i++)
        // {
        //     for(int j = 0; j < 256; j++)
        //     {
        //         std::cout << A[i][j] << " ";
        //     }
        //     std::cout << "\n";
        // }
    }
    return 0;
}

void EncryptionIdentify::sha256_transform(SHA256_CTX *ctx, const BYTE data[])
{
    WORD a, b, c, d, e, f, g, h, i, j, t1, t2, m[64];

	// initialization 
	for (i = 0, j = 0; i < 16; ++i, j += 4)
		m[i] = (data[j] << 24) | (data[j + 1] << 16) | (data[j + 2] << 8) | (data[j + 3]);
	for ( ; i < 64; ++i)
		m[i] = SIG1(m[i - 2]) + m[i - 7] + SIG0(m[i - 15]) + m[i - 16];

	a = ctx->state[0];
	b = ctx->state[1];
	c = ctx->state[2];
	d = ctx->state[3];
	e = ctx->state[4];
	f = ctx->state[5];
	g = ctx->state[6];
	h = ctx->state[7];

	for (i = 0; i < 64; ++i) {
		t1 = h + EP1(e) + CH(e,f,g) + k[i] + m[i];
		t2 = EP0(a) + MAJ(a,b,c);
		h = g;
		g = f;
		f = e;
		e = d + t1;
		d = c;
		c = b;
		b = a;
		a = t1 + t2;
	}

	ctx->state[0] += a;
	ctx->state[1] += b;
	ctx->state[2] += c;
	ctx->state[3] += d;
	ctx->state[4] += e;
	ctx->state[5] += f;
	ctx->state[6] += g;
	ctx->state[7] += h;
}

void EncryptionIdentify::sha256_init(SHA256_CTX *ctx)
{
    ctx->datalen = 0;
	ctx->bitlen = 0;
	ctx->state[0] = 0x6a09e667;
	ctx->state[1] = 0xbb67ae85;
	ctx->state[2] = 0x3c6ef372;
	ctx->state[3] = 0xa54ff53a;
	ctx->state[4] = 0x510e527f;
	ctx->state[5] = 0x9b05688c;
	ctx->state[6] = 0x1f83d9ab;
	ctx->state[7] = 0x5be0cd19;
}

void EncryptionIdentify::sha256_update(SHA256_CTX *ctx, const BYTE data[], size_t len)
{
    WORD i;

	for (i = 0; i < len; ++i) {
		ctx->data[ctx->datalen] = data[i];
		ctx->datalen++;
		if (ctx->datalen == 64) {
			// 64 byte = 512 bit  means the buffer ctx->data has fully stored one chunk of message
			// so do the sha256 hash map for the current chunk
			sha256_transform(ctx, ctx->data);
			ctx->bitlen += 512;
			ctx->datalen = 0;
		}
	}
}

void EncryptionIdentify::sha256_final(SHA256_CTX *ctx, BYTE hash[])
{
    WORD i;

	i = ctx->datalen;

	// Pad whatever data is left in the buffer.
	if (ctx->datalen < 56) {
		ctx->data[i++] = 0x80;  // pad 10000000 = 0x80
		while (i < 56)
			ctx->data[i++] = 0x00;
	}
	else {
		ctx->data[i++] = 0x80;
		while (i < 64)
			ctx->data[i++] = 0x00;
		sha256_transform(ctx, ctx->data);
		memset(ctx->data, 0, 56);
	}

	// Append to the padding the total message's length in bits and transform.
	ctx->bitlen += ctx->datalen * 8;
	ctx->data[63] = ctx->bitlen;
	ctx->data[62] = ctx->bitlen >> 8;
	ctx->data[61] = ctx->bitlen >> 16;
	ctx->data[60] = ctx->bitlen >> 24;
	ctx->data[59] = ctx->bitlen >> 32;
	ctx->data[58] = ctx->bitlen >> 40;
	ctx->data[57] = ctx->bitlen >> 48;
	ctx->data[56] = ctx->bitlen >> 56;
	sha256_transform(ctx, ctx->data);

	// copying the final state to the output hash(use big endian).
	for (i = 0; i < 4; ++i) {
		hash[i]      = (ctx->state[0] >> (24 - i * 8)) & 0x000000ff;
		hash[i + 4]  = (ctx->state[1] >> (24 - i * 8)) & 0x000000ff;
		hash[i + 8]  = (ctx->state[2] >> (24 - i * 8)) & 0x000000ff;
		hash[i + 12] = (ctx->state[3] >> (24 - i * 8)) & 0x000000ff;
		hash[i + 16] = (ctx->state[4] >> (24 - i * 8)) & 0x000000ff;
		hash[i + 20] = (ctx->state[5] >> (24 - i * 8)) & 0x000000ff;
		hash[i + 24] = (ctx->state[6] >> (24 - i * 8)) & 0x000000ff;
		hash[i + 28] = (ctx->state[7] >> (24 - i * 8)) & 0x000000ff;
	}
}

void EncryptionIdentify::genZZ(unsigned int equipmentCode)
{
    ctx = new SHA256_CTX;

    unsigned char buf[4];
    memcpy(buf, &equipmentCode, sizeof(equipmentCode));

    sha256_init(ctx);
    sha256_update(ctx, buf, sizeof(buf));
    sha256_final(ctx, hash);

    for(int i = 0; i <= 28; i += 4)
    {
        std::cout << std::hex << *(unsigned int *)(hash + i) << std::endl;
    }
}

std::vector<std::string> EncryptionIdentify::split(const std::string &str, const std::string &pattern)
{
    std::vector<std::string> res;
    if(str == "") return res;
    std::string strs = str + pattern;
    size_t pos = str.find(pattern);

    while(pos != str.npos)
    {
        std::string temp = strs.substr(0, pos);
        res.push_back(temp);
        strs = strs.substr(pos+1, strs.size());
        pos = strs.find(pattern);
    }

    return res;
}

unsigned short EncryptionIdentify::safeMapXYtoR(unsigned char X, unsigned char Y)
{
    return A[X][Y];
}

int EncryptionIdentify::combineData(unsigned short & R, unsigned char hash[], unsigned char * dBodyBuf, int dBodyLen)
{
    std::cout << sizeof(R) << std::endl;
    std::cout << 32 << std::endl;
    std::cout << dBodyLen << std::endl;

    int len = sizeof(R) + 32 + dBodyLen;
    std::cout << len << std::endl;

    buf = new unsigned char[len];
    memcpy(buf, &R, sizeof(R));
    std::cout << *(unsigned short *)buf << std::endl;
    memcpy(buf+sizeof(R), hash, 32);
    // for(int i = 0; i < 32; i++)
    // {
    //     *(buf+2+i) = *(hash+i);
    // }
    std::cout << std::hex << *(unsigned long long *)(buf + 2) << std::endl;
    memcpy(buf+sizeof(R)+32, dBodyBuf, dBodyLen);
    return len;
}

unsigned char EncryptionIdentify::swapBit8(unsigned char & byte8)
{
    byte8 = (byte8 >> 7 & 0x01) | (byte8 >> 5 & 0x02) | (byte8 >> 3 & 0x04) | (byte8 >> 1 & 0x08) | 
             (byte8 << 7 & 0x80) | (byte8 << 5 & 0x40) | (byte8 << 3 & 0x20) | (byte8 << 1 & 0x10);
    return byte8;
}

unsigned short EncryptionIdentify::swapBit16(unsigned short & buf16)
{
    buf16 = ((((buf16 >> 7 & 0x0100) | (buf16 >> 5 & 0x0200) | (buf16 >> 3 & 0x0400) | (buf16 >> 1 & 0x0800)) | 
            ((buf16 << 7 & 0x8000) | (buf16 << 5 & 0x4000) | (buf16 << 3 & 0x2000) | (buf16 << 1 & 0x1000))) >> 8) | 
            ((((buf16 >> 7 & 0x0001) | (buf16 >> 5 & 0x0002) | (buf16 >> 3 & 0x0004) | (buf16 >> 1 & 0x0008)) | 
            ((buf16 << 7 & 0x0080) | (buf16 << 5 & 0x0040) | (buf16 << 3 & 0x0020) | (buf16 << 1 & 0x0010))) << 8);
    return buf16;
}

unsigned short EncryptionIdentify::genJMByCRC16IBM(unsigned char * buf, int len)
{
    unsigned char j;
    register unsigned short crc=0x0000;

    for(int i = 0; i < len; i++)
    {
        unsigned char byte = *(unsigned char *)(buf + i);
        byte = swapBit8(byte);
        crc = (crc ^ byte) << 8;
        printf("%hu\n", crc);
        for(j = 8; j > 0; --j)
        {
            if(crc & 0x8000)
            {
                crc = (crc << 1) ^ 0x8005;
            }
            else
            {
                crc = crc << 1;
            }
        }
    }
    crc = swapBit16(crc) ^ 0x0000;
    printf("%hu\n", crc);
    return crc;
}