package geoinfo.com;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class KISA_SHA256 {

	BASE64Encoder encoder = new BASE64Encoder();
	BASE64Decoder decoder = new BASE64Decoder();

	public String Sha256Encrypt(byte[] plainTextByte) throws Exception {
		
		byte[] bszDigest = new byte[32];

		SHA256_Encrypt( plainTextByte, plainTextByte.length, bszDigest );
		return encoder.encode(bszDigest);
	}

	public byte[] Sha256EncryptB(byte[] plainTextByte) throws Exception {
		
		byte[] bszDigest = new byte[32];

		SHA256_Encrypt( plainTextByte, plainTextByte.length, bszDigest );
		return bszDigest;
	}



	public static final int BIG_ENDIAN = 0;
	public static final int LITTLE_ENDIAN = 1;

	public static void arraycopy(byte[] dst, byte[] src, int length) {
		for(int i=0; i<length; i++) {
			dst[i] = src[i];
		}
	}

	public static void arraycopy_offset(byte[] dst, int dst_offset, byte[] src, int src_offset, int length) {
		for(int i=0; i<length; i++) {
			dst[dst_offset+i] = src[src_offset+i];
		}
	}

	public static void arrayinit(byte[] dst, byte value, int length) {
		for(int i=0; i<length; i++) {
			dst[i] = value;
		}
	}

	public static void arrayinit_offset(byte[] dst, int dst_offset, byte value, int length) {
		for(int i=0; i<length; i++) {
			dst[dst_offset+i] = value;
		}
	}

	public static void memcpy(int[] dst, byte[] src, int length, int ENDIAN) {
		int iLen = length / 4;
		for(int i=0; i<iLen; i++) {
			byte_to_int(dst, i, src, i*4, ENDIAN);
		}
	}

	public static void memcpy(int[] dst, int[] src, int src_offset, int length) {
		int iLen = length / 4 + ((length % 4 != 0)?1:0);
		for(int i=0; i<iLen; i++) {
			dst[i] = src[src_offset+i];
		}
	}

	public static void set_byte_for_int(int[] dst, int b_offset, byte value, int ENDIAN) {
		if(ENDIAN == BIG_ENDIAN) {
			int shift_value = (3-b_offset%4)*8;
			int mask_value =  0x0ff << shift_value;
			int mask_value2 = ~mask_value;
			int value2 = (value&0x0ff) << shift_value;
			dst[b_offset/4] = (dst[b_offset/4] & mask_value2) | (value2 & mask_value);    
		} else {
			int shift_value = (b_offset%4)*8;
			int mask_value =  0x0ff << shift_value;
			int mask_value2 = ~mask_value;
			int value2 = (value&0x0ff) << shift_value;
			dst[b_offset/4] = (dst[b_offset/4] & mask_value2) | (value2 & mask_value);    
		}
	}

	public static byte get_byte_for_int(int[] src, int b_offset, int ENDIAN) {
		if(ENDIAN == BIG_ENDIAN) {
			int shift_value = (3-b_offset%4)*8;
			int mask_value =  0x0ff << shift_value;
			int value = (src[b_offset/4] & mask_value) >> shift_value;
			return (byte)value;
		} else {
			int shift_value = (b_offset%4)*8;
			int mask_value =  0x0ff << shift_value;
			int value = (src[b_offset/4] & mask_value) >> shift_value;
			return (byte)value;
		}
		
	}

	public static byte[] get_bytes_for_ints(int[] src, int offset, int ENDIAN) {
		int iLen = src.length-offset;
		byte[] result = new byte[(iLen)*4];
		for(int i=0; i<iLen; i++) {
			int_to_byte(result, i*4, src, offset+i, ENDIAN);
		}
		
		return result;
	}

	public static void byte_to_int(int[] dst, int dst_offset, byte[] src, int src_offset, int ENDIAN) {
		if(ENDIAN == BIG_ENDIAN) {
			dst[dst_offset] = ((0x0ff&src[src_offset]) << 24) | ((0x0ff&src[src_offset+1]) << 16) | ((0x0ff&src[src_offset+2]) << 8) | ((0x0ff&src[src_offset+3]));
		} else {
			dst[dst_offset] = ((0x0ff&src[src_offset])) | ((0x0ff&src[src_offset+1]) << 8) | ((0x0ff&src[src_offset+2]) << 16) | ((0x0ff&src[src_offset+3]) << 24);
		}
	}

	public static int byte_to_int(byte[] src, int src_offset, int ENDIAN) {
		if(ENDIAN == BIG_ENDIAN) {
			return ((0x0ff&src[src_offset]) << 24) | ((0x0ff&src[src_offset+1]) << 16) | ((0x0ff&src[src_offset+2]) << 8) | ((0x0ff&src[src_offset+3]));
		} else {
			return ((0x0ff&src[src_offset])) | ((0x0ff&src[src_offset+1]) << 8) | ((0x0ff&src[src_offset+2]) << 16) | ((0x0ff&src[src_offset+3]) << 24);
		}
	}

	public static int byte_to_int_big_endian(byte[] src, int src_offset) {
		return ((0x0ff&src[src_offset]) << 24) | ((0x0ff&src[src_offset+1]) << 16) | ((0x0ff&src[src_offset+2]) << 8) | ((0x0ff&src[src_offset+3]));
	}

	public static void int_to_byte(byte[] dst, int dst_offset, int[] src, int src_offset, int ENDIAN) {
		int_to_byte_unit(dst, dst_offset, src[src_offset], ENDIAN);
	}

	public static void int_to_byte_unit(byte[] dst, int dst_offset, int src, int ENDIAN) {
		if(ENDIAN == BIG_ENDIAN) {
			dst[dst_offset] = (byte)((src>> 24) & 0x0ff);
			dst[dst_offset+1] = (byte)((src >> 16) & 0x0ff);
			dst[dst_offset+2] = (byte)((src >> 8) & 0x0ff);
			dst[dst_offset+3] = (byte)((src) & 0x0ff);
		} else {
			dst[dst_offset] = (byte)((src) & 0x0ff);
			dst[dst_offset+1] = (byte)((src >> 8) & 0x0ff);
			dst[dst_offset+2] = (byte)((src >> 16) & 0x0ff);
			dst[dst_offset+3] = (byte)((src >> 24) & 0x0ff);
		}
		
	}

	public static void int_to_byte_unit_big_endian(byte[] dst, int dst_offset, int src) {
		dst[dst_offset] = (byte)((src>> 24) & 0x0ff);
		dst[dst_offset+1] = (byte)((src >> 16) & 0x0ff);
		dst[dst_offset+2] = (byte)((src >> 8) & 0x0ff);
		dst[dst_offset+3] = (byte)((src) & 0x0ff);
	}

	public static int URShift(int x, int n) {
		if(n == 0)
			return x;
		if(n >= 32)
			return 0;
		int v = x >> n;
		int v_mask = ~(0x80000000 >> (n-1));
		return v & v_mask;
	}

	public static final long INT_RANGE_MAX = (long)Math.pow(2, 32);

	public static long intToUnsigned(int x) {
		if(x >= 0)
			return x;
		return x + INT_RANGE_MAX;
	}



	// DEFAULT : JAVA = BIG_ENDIAN
	private static int ENDIAN = BIG_ENDIAN;

	private static final int SHA256_DIGEST_BLOCKLEN = 64;
	private static final int SHA256_DIGEST_VALUELEN = 32;

	private static final int SHA256_K[] =
	{
		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
	};


	private static final int ROTL_ULONG(int x, int n) {
		return (x << n) | URShift(x, 32 - n);
	}

	private static final int ROTR_ULONG(int x, int n) {
		return URShift(x, n) | (x << (32 - (n)));
	}

	private static final int ENDIAN_REVERSE_ULONG(int dwS) {
		return ( (ROTL_ULONG((dwS),  8) & 0x00ff00ff) | (ROTL_ULONG((dwS), 24) & 0xff00ff00) );
	}

	private static final void BIG_D2B(int D, byte[] B, int B_offset) {
		int_to_byte_unit(B, B_offset, D, ENDIAN);
	}

	private static final int RR(int x, int n) { return ROTR_ULONG(x, n); }
	private static final int SS(int x, int n) { return URShift(x, n); }

	private static final int Ch(int x, int y, int z) { return ((x & y) ^ ((~x) & z)); }
	private static final int Maj(int x, int y, int z) { return ((x & y) ^ (x & z) ^ (y & z)); }
	private static final int Sigma0(int x) { return (RR(x,  2) ^ RR(x, 13) ^ RR(x, 22)); }
	private static final int Sigma1(int x) { return (RR(x,  6) ^ RR(x, 11) ^ RR(x, 25)); }

	private static final int RHO0(int x) { return (RR(x,  7) ^ RR(x, 18) ^ SS(x,  3)); }
	private static final int RHO1(int x) { return (RR(x, 17) ^ RR(x, 19) ^ SS(x, 10)); }

	private static final int abcdefgh_a = 0;
	private static final int abcdefgh_b = 1;
	private static final int abcdefgh_c = 2;
	private static final int abcdefgh_d = 3;
	private static final int abcdefgh_e = 4;
	private static final int abcdefgh_f = 5;
	private static final int abcdefgh_g = 6;
	private static final int abcdefgh_h = 7;

	private static final void FF(int[] abcdefgh, int a, int b, int c, int d, int e, int f, int g, int h, int[] X, int j) {
		long T1;
		T1 = intToUnsigned(abcdefgh[h]) + intToUnsigned(Sigma1(abcdefgh[e])) + intToUnsigned(Ch(abcdefgh[e], abcdefgh[f], abcdefgh[g])) + intToUnsigned(SHA256_K[j]) + intToUnsigned(X[j]);
		abcdefgh[d] += T1;
		abcdefgh[h] = (int)(T1 + intToUnsigned(Sigma0(abcdefgh[a])) + intToUnsigned(Maj(abcdefgh[a], abcdefgh[b], abcdefgh[c])));
	}
	private static final int GetData(byte[] x, int x_offset) {
		return byte_to_int(x, x_offset, ENDIAN);
	}
	//*********************************************************************************************************************************
	// o SHA256_Transform() : 512 비트 단위 블록의 메시지를 입력 받아 연쇄변수를 갱신하는 압축 함수로써
//		                      4 라운드(64 단계)로 구성되며 8개의 연쇄변수(a, b, c, d, e, f, g, h)를 사용
	// o 입력                               : Message               - 입력 메시지의 포인터 변수
//		                      ChainVar              - 연쇄변수의 포인터 변수
	// o 출력                               :
	//*********************************************************************************************************************************
	private static void SHA256_Transform(byte[] Message, int[] ChainVar) {
		int abcdefgh[] = new int[8];
		int T1[] = new int[1];
		int X[] = new int[64];
		int j;

		for (j = 0; j < 16; j++)
			X[j] = GetData(Message, j*4);

		for (j = 16; j < 64; j++)
			X[j] = (int)(intToUnsigned(RHO1(X[j - 2])) + intToUnsigned(X[j - 7]) + intToUnsigned(RHO0(X[j - 15])) + intToUnsigned(X[j - 16]));

		abcdefgh[abcdefgh_a] = ChainVar[0];
		abcdefgh[abcdefgh_b] = ChainVar[1];
		abcdefgh[abcdefgh_c] = ChainVar[2];
		abcdefgh[abcdefgh_d] = ChainVar[3];
		abcdefgh[abcdefgh_e] = ChainVar[4];
		abcdefgh[abcdefgh_f] = ChainVar[5];
		abcdefgh[abcdefgh_g] = ChainVar[6];
		abcdefgh[abcdefgh_h] = ChainVar[7];

		for (j = 0; j < 64; j += 8)
		{
			FF(abcdefgh, abcdefgh_a, abcdefgh_b, abcdefgh_c, abcdefgh_d, abcdefgh_e, abcdefgh_f, abcdefgh_g, abcdefgh_h, X, j + 0);
			FF(abcdefgh, abcdefgh_h, abcdefgh_a, abcdefgh_b, abcdefgh_c, abcdefgh_d, abcdefgh_e, abcdefgh_f, abcdefgh_g, X, j + 1);
			FF(abcdefgh, abcdefgh_g, abcdefgh_h, abcdefgh_a, abcdefgh_b, abcdefgh_c, abcdefgh_d, abcdefgh_e, abcdefgh_f, X, j + 2);
			FF(abcdefgh, abcdefgh_f, abcdefgh_g, abcdefgh_h, abcdefgh_a, abcdefgh_b, abcdefgh_c, abcdefgh_d, abcdefgh_e, X, j + 3);
			FF(abcdefgh, abcdefgh_e, abcdefgh_f, abcdefgh_g, abcdefgh_h, abcdefgh_a, abcdefgh_b, abcdefgh_c, abcdefgh_d, X, j + 4);
			FF(abcdefgh, abcdefgh_d, abcdefgh_e, abcdefgh_f, abcdefgh_g, abcdefgh_h, abcdefgh_a, abcdefgh_b, abcdefgh_c, X, j + 5);
			FF(abcdefgh, abcdefgh_c, abcdefgh_d, abcdefgh_e, abcdefgh_f, abcdefgh_g, abcdefgh_h, abcdefgh_a, abcdefgh_b, X, j + 6);
			FF(abcdefgh, abcdefgh_b, abcdefgh_c, abcdefgh_d, abcdefgh_e, abcdefgh_f, abcdefgh_g, abcdefgh_h, abcdefgh_a, X, j + 7);
		}

		ChainVar[0] += abcdefgh[abcdefgh_a];
		ChainVar[1] += abcdefgh[abcdefgh_b];
		ChainVar[2] += abcdefgh[abcdefgh_c];
		ChainVar[3] += abcdefgh[abcdefgh_d];
		ChainVar[4] += abcdefgh[abcdefgh_e];
		ChainVar[5] += abcdefgh[abcdefgh_f];
		ChainVar[6] += abcdefgh[abcdefgh_g];
		ChainVar[7] += abcdefgh[abcdefgh_h];
	}

	/**
	@brief 연쇄변수와 길이변수를 초기화하는 함수
	@param Info : SHA256_Process 호출 시 사용되는 구조체
	*/
	public static void SHA256_Init( SHA256_INFO Info ) {
		Info.uChainVar[0] = 0x6a09e667;
		Info.uChainVar[1] = 0xbb67ae85;
		Info.uChainVar[2] = 0x3c6ef372;
		Info.uChainVar[3] = 0xa54ff53a;
		Info.uChainVar[4] = 0x510e527f;
		Info.uChainVar[5] = 0x9b05688c;
		Info.uChainVar[6] = 0x1f83d9ab;
		Info.uChainVar[7] = 0x5be0cd19;

		Info.uHighLength = Info.uLowLength = 0;
	}

	/**
	@brief 연쇄변수와 길이변수를 초기화하는 함수
	@param Info : SHA256_Init 호출하여 초기화된 구조체(내부적으로 사용된다.)
	@param pszMessage : 사용자 입력 평문
	@param inLen : 사용자 입력 평문 길이
	*/
	public static void SHA256_Process( SHA256_INFO Info, byte[] pszMessage, int uDataLen ) {
		int pszMessage_offset;

		if((Info.uLowLength += (uDataLen << 3)) < 0) {
			Info.uHighLength++;
		}

		Info.uHighLength += URShift(uDataLen,29);

		pszMessage_offset = 0;
		while (uDataLen >= SHA256_DIGEST_BLOCKLEN) {
			arraycopy_offset(Info.szBuffer, 0, pszMessage, pszMessage_offset, SHA256_DIGEST_BLOCKLEN);
			SHA256_Transform(Info.szBuffer, Info.uChainVar);
			pszMessage_offset += SHA256_DIGEST_BLOCKLEN;
			uDataLen -= SHA256_DIGEST_BLOCKLEN;
		}

		arraycopy_offset(Info.szBuffer, 0, pszMessage, pszMessage_offset, uDataLen);
	}

	/**
	@brief 메시지 덧붙이기와 길이 덧붙이기를 수행한 후 마지막 메시지 블록을 가지고 압축함수를 호출하는 함수
	@param Info : SHA256_Init 호출하여 초기화된 구조체(내부적으로 사용된다.)
	@param pszDigest : 암호문
	*/
	public static void SHA256_Close( SHA256_INFO Info, byte[] pszDigest ) {
		int i, Index;

		Index = URShift(Info.uLowLength, 3) % SHA256_DIGEST_BLOCKLEN;
		Info.szBuffer[Index++] = (byte)0x80;

		if (Index > SHA256_DIGEST_BLOCKLEN - 8) {
			arrayinit_offset(Info.szBuffer, Index, (byte)0, SHA256_DIGEST_BLOCKLEN - Index);
			SHA256_Transform(Info.szBuffer, Info.uChainVar);
			arrayinit(Info.szBuffer, (byte)0, SHA256_DIGEST_BLOCKLEN - 8);
		}
		else {
			arrayinit_offset(Info.szBuffer, Index, (byte)0, SHA256_DIGEST_BLOCKLEN - Index - 8);
		}

		if(ENDIAN == LITTLE_ENDIAN) {
			Info.uLowLength = ENDIAN_REVERSE_ULONG(Info.uLowLength);
			Info.uHighLength = ENDIAN_REVERSE_ULONG(Info.uHighLength);
		}

		int_to_byte_unit(Info.szBuffer, ((int)(SHA256_DIGEST_BLOCKLEN / 4 - 2))*4, Info.uHighLength, ENDIAN);
		int_to_byte_unit(Info.szBuffer, ((int)(SHA256_DIGEST_BLOCKLEN / 4 - 1))*4, Info.uLowLength, ENDIAN);

		SHA256_Transform(Info.szBuffer, Info.uChainVar);

		for (i = 0; i < SHA256_DIGEST_VALUELEN; i += 4)
			BIG_D2B((Info.uChainVar)[i / 4], pszDigest, i);
	}

	/**
	@brief 사용자 입력 평문을 한번에 처리
	@param pszMessage : 사용자 입력 평문
	@param pszDigest : 암호문
	@remarks 내부적으로 SHA256_Init, SHA256_Process, SHA256_Close를 호출한다.
	*/
	public static void SHA256_Encrypt( byte[] pszMessage, int uPlainTextLen, byte[] pszDigest ) {
		SHA256_INFO info = new SHA256_INFO();
		SHA256_Init( info );
		SHA256_Process( info, pszMessage, uPlainTextLen );
		SHA256_Close( info, pszDigest );
	}


	public static class SHA256_INFO {
		public int uChainVar[] = new int[SHA256_DIGEST_VALUELEN / 4];
		public int uHighLength;
		public int uLowLength;
		public byte szBuffer[] = new byte[SHA256_DIGEST_BLOCKLEN];
	}

	public byte[] getBytes(String data) {
		String[] str = data.split(",");
		byte[] result = new byte[str.length];
		for(int i=0; i<result.length; i++) {
			result[i] = getHex(str[i]);
		}
		return result;
	}

	public String getString(byte[] data) {
		String result = "";
		for(int i=0; i<data.length; i++) {
			result = result + toHex(data[i]);
		}
		return result;
	}

	public byte getHex(String str) {
		str = str.trim();
		if(str.length() == 0)
			str = "00";
		else if(str.length() == 1)
			str = "0" + str;
		
		str = str.toUpperCase();
		return (byte)(getHexNibble(str.charAt(0)) * 16 + getHexNibble(str.charAt(1)));
	}

	public byte getHexNibble(char c) {
		if(c >= '0' && c<='9')
			return (byte)(c - '0');
		if(c >= 'A' && c<='F')
			return (byte)(c - 'A' + 10);
		return 0;
	}

	public String toHex(int b) {
		char c[] = new char[2];
		c[0] = toHexNibble((b>>4) & 0x0f);
		c[1] = toHexNibble(b & 0x0f);
		return new String(c);
	}

	public char toHexNibble(int b) {
		if(b >= 0 && b <= 9)
			return (char)(b + '0');
		if(b >= 0x0a && b <= 0x0f)
			return (char)(b + 'A' - 10);
		return '0';
	}
}
	// private String shaEncrypt(String plainTextStr){
//	 	String encrypt_plainText = "";
//	 	String encrypt_cipherText = "";
//	 	String encrypt_cipherText_base64 = "";
//	 	String shaPassTemp = "";
//	 	String shaPass = "";

//	 		byte[] plainText = plainTextStr.getBytes("UTF-8");
//	 		String cipherTextStr = getString(Sha256EncryptB(plainText));

//	 		encrypt_plainText = plainTextStr;
	// // 		encrypt_cipherText = cipherTextStr;
//	 		shaPassTemp = encrypt_cipherText.substring(0,20);
//	 		shaPass = shaPassTemp.toLowerCase();
//	 	return shaPass;
	// }