//-----------------------------------------------------------------------------
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Low frequency Jablotron tag commands
// Differential Biphase, RF/64, 64 bits long (complete)
//-----------------------------------------------------------------------------

#include "cmdlfjablotron.h"

static int CmdHelp(const char *Cmd);

int usage_lf_jablotron_clone(void){
	PrintAndLog("clone a Jablotron tag to a T55x7 tag.");
	PrintAndLog("Usage: lf jablotron clone [h] <card ID> <Q5>");
	PrintAndLog("Options:");
	PrintAndLog("      h          : This help");
	PrintAndLog("      <card ID>  : jablotron card ID");
	PrintAndLog("      <Q5>       : specify write to Q5 (t5555 instead of t55x7)");
	PrintAndLog("");
	PrintAndLog("Sample: lf jablotron clone 112233");
	return 0;
}

int usage_lf_jablotron_sim(void) {
	PrintAndLog("Enables simulation of jablotron card with specified card number.");
	PrintAndLog("Simulation runs until the button is pressed or another USB command is issued.");
	PrintAndLog("");
	PrintAndLog("Usage:  lf jablotron sim [h] <card ID>");
	PrintAndLog("Options:");
	PrintAndLog("      h          : This help");
	PrintAndLog("      <card ID>  : jablotron card ID");
	PrintAndLog("");
	PrintAndLog("Sample: lf jablotron sim 112233");
	return 0;
}

static uint8_t jablontron_chksum(uint8_t *bits){
	uint8_t chksum = 0;
	for (int i=16; i < 56; i += 8) {
		chksum += bytebits_to_byte(bits+i,8);
	}
	chksum ^= 0x3A;	
	return chksum;
}

int getJablotronBits(uint64_t fullcode, uint8_t *bits) {	
	//preamp
	num_to_bytebits(0xFFFF, 16, bits);

	//fullcode
	num_to_bytebits(fullcode, 40, bits+16);

	//chksum byte
	uint8_t chksum = jablontron_chksum(bits);
	num_to_bytebits(chksum, 8, bits+56);
	return 1;
}

// ASK/Diphase fc/64 (inverted Biphase)
// Note: this is not a demod, this is only a detection
// the parameter *bits needs to be demoded before call
// 0xFFFF preamble, 64bits
int detectJablotron(uint8_t *bits, size_t *size) {
	if (*size < 64*2) return -1; //make sure buffer has enough data
	size_t startIdx = 0;
	uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0};
	if (preambleSearch(bits, preamble, sizeof(preamble), size, &startIdx) == 0)
		return -2; //preamble not found
	if (*size != 64) return -3; // wrong demoded size
	
	uint8_t checkchksum = jablontron_chksum(bits+startIdx);
	uint8_t crc = bytebits_to_byte(bits+startIdx+56, 8);
	if ( checkchksum != crc ) return -5;
	return (int)startIdx;
}

static uint64_t getJablontronCardId( uint64_t rawcode ){
	uint64_t id = 0;
	uint8_t bytes[] = {0,0,0,0,0};
	num_to_bytes(rawcode, 5, bytes);
	for ( int i = 4, j = 0; i > -1;  --i, j += 2 ) {
		id += NIBBLE_LOW( bytes[i] ) * (int)pow(10,j);
		id += NIBBLE_HIGH( bytes[i] ) * (int)pow(10,j+1);
	}
	return id;
}

//see ASKDemod for what args are accepted
int CmdJablotronDemod(const char *Cmd) {

	//Differential Biphase / di-phase (inverted biphase)
	//get binary from ask wave
	if (!ASKbiphaseDemod("0 64 1 0", false)) {
		if (g_debugMode) PrintAndLog("DEBUG: Error - Jablotron ASKbiphaseDemod failed");
		return 0;
	}
	size_t size = DemodBufferLen;
	int ans = detectJablotron(DemodBuffer, &size);
	if (ans < 0){
		if (g_debugMode){
			if (ans == -1)
				PrintAndLog("DEBUG: Error - Jablotron too few bits found");
			else if (ans == -2)
				PrintAndLog("DEBUG: Error - Jablotron preamble not found");
			else if (ans == -3)
				PrintAndLog("DEBUG: Error - Jablotron size not correct: %d", size);
			else if (ans == -5)
				PrintAndLog("DEBUG: Error - Jablotron checksum failed");
			else
				PrintAndLog("DEBUG: Error - Jablotron ans: %d", ans);
		}
		return 0;
	}

	setDemodBuf(DemodBuffer, 64, ans);
	setClockGrid(g_DemodClock, g_DemodStartIdx + (ans*g_DemodClock));
	
	//got a good demod
	uint32_t raw1 = bytebits_to_byte(DemodBuffer, 32);
	uint32_t raw2 = bytebits_to_byte(DemodBuffer+32, 32);

	uint64_t rawid = bytebits_to_byte(DemodBuffer+16, 40);
	uint64_t id = getJablontronCardId(rawid);

	PrintAndLog("Jablotron Tag Found: Card ID: %"PRIx64" :: Raw: %08X%08X", id, raw1, raw2);

	uint8_t chksum = raw2 & 0xFF;
	PrintAndLog("Checksum: %02X [%s]",
		chksum,
		(chksum == jablontron_chksum(DemodBuffer)) ? "OK":"FAIL"		
	);

	id = DEC2BCD(id);
	// Printed format: 1410-nn-nnnn-nnnn	
	PrintAndLog("Printed: 1410-%02X-%04X-%04X",
		(uint8_t)(id >> 32) & 0xFF,
		(uint16_t)(id >> 16) & 0xFFFF,
		(uint16_t)id & 0xFFFF
	);
	return 1;
}

int CmdJablotronRead(const char *Cmd) {
	lf_read(true, 10000);
	return CmdJablotronDemod(Cmd);
}

int CmdJablotronClone(const char *Cmd) {

	uint64_t fullcode = 0;
	uint32_t blocks[3] = {T55x7_MODULATION_DIPHASE | T55x7_BITRATE_RF_64 | 2 << T55x7_MAXBLOCK_SHIFT, 0, 0};

	uint8_t bits[64];
	memset(bits, 0, sizeof(bits));
	
	char cmdp = param_getchar(Cmd, 0);
	if (strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') return usage_lf_jablotron_clone();

	fullcode = param_get64ex(Cmd, 0, 0, 16);
	
	//Q5
	if (param_getchar(Cmd, 1) == 'Q' || param_getchar(Cmd, 1) == 'q')
		blocks[0] = T5555_MODULATION_BIPHASE | T5555_INVERT_OUTPUT | T5555_SET_BITRATE(64) | 2 << T5555_MAXBLOCK_SHIFT;
	
	// clearing the topbit needed for the preambl detection. 
	if ((fullcode & 0x7FFFFFFFFF) != fullcode) {
		fullcode &= 0x7FFFFFFFFF;
		PrintAndLog("Card Number Truncated to 39bits: %"PRIx64, fullcode);
	}
	
	if ( !getJablotronBits(fullcode, bits)) {
		PrintAndLog("Error with tag bitstream generation.");
		return 1;
	}	
	
	blocks[1] = bytebits_to_byte(bits, 32);
	blocks[2] = bytebits_to_byte(bits + 32, 32);

	PrintAndLog("Preparing to clone Jablotron to T55x7 with FullCode: %"PRIx64, fullcode);
	print_blocks(blocks, 3);
	
	UsbCommand resp;
	UsbCommand c = {CMD_T55XX_WRITE_BLOCK, {0,0,0}};

	for (uint8_t i=0; i<4; i++) {
		c.arg[0] = blocks[i];
		c.arg[1] = i;
		clearCommandBuffer();
		SendCommand(&c);
		if (!WaitForResponseTimeout(CMD_ACK, &resp, T55XX_WRITE_TIMEOUT)){
			PrintAndLog("Error occurred, device did not respond during write operation.");
			return -1;
		}
	}
    return 0;
}

int CmdJablotronSim(const char *Cmd) {
	uint64_t fullcode = 0;

	char cmdp = param_getchar(Cmd, 0);
	if (strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') return usage_lf_jablotron_sim();

	fullcode = param_get64ex(Cmd, 0, 0, 16);

	// clearing the topbit needed for the preambl detection. 
	if ((fullcode & 0x7FFFFFFFFF) != fullcode) {
		fullcode &= 0x7FFFFFFFFF;
		PrintAndLog("Card Number Truncated to 39bits: %"PRIx64, fullcode);
	}
	
	uint8_t clk = 64, encoding = 2, separator = 0, invert = 1;
	uint16_t arg1, arg2;
	size_t size = 64;
	arg1 = clk << 8 | encoding;
	arg2 = invert << 8 | separator;

	PrintAndLog("Simulating Jablotron - FullCode: %"PRIx64, fullcode);

	UsbCommand c = {CMD_ASK_SIM_TAG, {arg1, arg2, size}};
	getJablotronBits(fullcode, c.d.asBytes);
	clearCommandBuffer();
	SendCommand(&c);
	return 0;
}

static command_t CommandTable[] = {
    {"help",	CmdHelp,			1, "This help"},
	{"demod",	CmdJablotronDemod,	1, "Demodulate an Jablotron tag from the GraphBuffer"},
	{"read",	CmdJablotronRead,	0, "Attempt to read and extract tag data from the antenna"},
	{"clone",	CmdJablotronClone,	0, "clone jablotron tag"},
	{"sim",		CmdJablotronSim,	0, "simulate jablotron tag"},
    {NULL, NULL, 0, NULL}
};

int CmdLFJablotron(const char *Cmd) {
	clearCommandBuffer();
    CmdsParse(CommandTable, Cmd);
    return 0;
}

int CmdHelp(const char *Cmd) {
    CmdsHelp(CommandTable);
    return 0;
}