//-----------------------------------------------------------------------------
// Iceman, 2019
//
// 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 GALLAGHER tag commands
// ASK/MAN, RF/32, 96 bits long (unknown cs) (0x00088060)
// sample Q5 ,  ASK RF/32, STT,  96 bits  (3blocks)   ( 0x9000F006)
//-----------------------------------------------------------------------------
#include "cmdlfgallagher.h"
#include <string.h>        // memcpy
#include <ctype.h>         // tolower
#include <stdio.h>
#include "commonutil.h"    // ARRAYLEN
#include "common.h"
#include "cmdparser.h"     // command_t
#include "comms.h"
#include "ui.h"
#include "cmddata.h"
#include "cmdlf.h"
#include "lfdemod.h"       // preamble test
#include "protocols.h"     // t55xx defines
#include "cmdlft55xx.h"    // clone..
#include "crc.h"           // CRC8/Cardx
#include "cmdlfem4x05.h"   //
#include "cliparser.h"

static int CmdHelp(const char *Cmd);

static void descramble(uint8_t *arr, uint8_t len) {

    uint8_t lut[] = {
        0xa3, 0xb0, 0x80, 0xc6, 0xb2, 0xf4, 0x5c, 0x6c, 0x81, 0xf1, 0xbb, 0xeb, 0x55, 0x67, 0x3c, 0x05,
        0x1a, 0x0e, 0x61, 0xf6, 0x22, 0xce, 0xaa, 0x8f, 0xbd, 0x3b, 0x1f, 0x5e, 0x44, 0x04, 0x51, 0x2e,
        0x4d, 0x9a, 0x84, 0xea, 0xf8, 0x66, 0x74, 0x29, 0x7f, 0x70, 0xd8, 0x31, 0x7a, 0x6d, 0xa4, 0x00,
        0x82, 0xb9, 0x5f, 0xb4, 0x16, 0xab, 0xff, 0xc2, 0x39, 0xdc, 0x19, 0x65, 0x57, 0x7c, 0x20, 0xfa,
        0x5a, 0x49, 0x13, 0xd0, 0xfb, 0xa8, 0x91, 0x73, 0xb1, 0x33, 0x18, 0xbe, 0x21, 0x72, 0x48, 0xb6,
        0xdb, 0xa0, 0x5d, 0xcc, 0xe6, 0x17, 0x27, 0xe5, 0xd4, 0x53, 0x42, 0xf3, 0xdd, 0x7b, 0x24, 0xac,
        0x2b, 0x58, 0x1e, 0xa7, 0xe7, 0x86, 0x40, 0xd3, 0x98, 0x97, 0x71, 0xcb, 0x3a, 0x0f, 0x01, 0x9b,
        0x6e, 0x1b, 0xfc, 0x34, 0xa6, 0xda, 0x07, 0x0c, 0xae, 0x37, 0xca, 0x54, 0xfd, 0x26, 0xfe, 0x0a,
        0x45, 0xa2, 0x2a, 0xc4, 0x12, 0x0d, 0xf5, 0x4f, 0x69, 0xe0, 0x8a, 0x77, 0x60, 0x3f, 0x99, 0x95,
        0xd2, 0x38, 0x36, 0x62, 0xb7, 0x32, 0x7e, 0x79, 0xc0, 0x46, 0x93, 0x2f, 0xa5, 0xba, 0x5b, 0xaf,
        0x52, 0x1d, 0xc3, 0x75, 0xcf, 0xd6, 0x4c, 0x83, 0xe8, 0x3d, 0x30, 0x4e, 0xbc, 0x08, 0x2d, 0x09,
        0x06, 0xd9, 0x25, 0x9e, 0x89, 0xf2, 0x96, 0x88, 0xc1, 0x8c, 0x94, 0x0b, 0x28, 0xf0, 0x47, 0x63,
        0xd5, 0xb3, 0x68, 0x56, 0x9c, 0xf9, 0x6f, 0x41, 0x50, 0x85, 0x8b, 0x9d, 0x59, 0xbf, 0x9f, 0xe2,
        0x8e, 0x6a, 0x11, 0x23, 0xa1, 0xcd, 0xb5, 0x7d, 0xc7, 0xa9, 0xc8, 0xef, 0xdf, 0x02, 0xb8, 0x03,
        0x6b, 0x35, 0x3e, 0x2c, 0x76, 0xc9, 0xde, 0x1c, 0x4b, 0xd1, 0xed, 0x14, 0xc5, 0xad, 0xe9, 0x64,
        0x4a, 0xec, 0x8d, 0xf7, 0x10, 0x43, 0x78, 0x15, 0x87, 0xe4, 0xd7, 0x92, 0xe1, 0xee, 0xe3, 0x90
    };

    for (int i = 0; i < len;  i++) {
        arr[i] = lut[arr[i]];
    }
}

//see ASK/MAN Demod for what args are accepted
int demodGallagher(bool verbose) {
    (void) verbose; // unused so far
    bool st = true;
    if (ASKDemod_ext(32, 0, 100, 0, false, false, false, 1, &st) != PM3_SUCCESS) {
        PrintAndLogEx(DEBUG, "DEBUG: Error - GALLAGHER: ASKDemod failed");
        return PM3_ESOFT;
    }

    size_t size = DemodBufferLen;
    int ans = detectGallagher(DemodBuffer, &size);
    if (ans < 0) {
        if (ans == -1)
            PrintAndLogEx(DEBUG, "DEBUG: Error - GALLAGHER: too few bits found");
        else if (ans == -2)
            PrintAndLogEx(DEBUG, "DEBUG: Error - GALLAGHER: preamble not found");
        else if (ans == -3)
            PrintAndLogEx(DEBUG, "DEBUG: Error - GALLAGHER: Size not correct: %zu", size);
        else
            PrintAndLogEx(DEBUG, "DEBUG: Error - GALLAGHER: ans: %d", ans);

        return PM3_ESOFT;
    }
    setDemodBuff(DemodBuffer, 96, 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);
    uint32_t raw3 = bytebits_to_byte(DemodBuffer + 64, 32);

    // bytes
    uint8_t arr[8] = {0};
    for (int i = 0, pos = 0; i < ARRAYLEN(arr); i++) {
        pos = (i * 8) + i;
        arr[i] = bytebits_to_byte(DemodBuffer + pos, 8);
        PrintAndLogEx(NORMAL, "%d -" NOLF, pos);
    }
    PrintAndLogEx(NORMAL, "");

    // crc
    uint8_t crc = bytebits_to_byte(DemodBuffer + 72, 8);
    uint8_t calc_crc =  CRC8Cardx(arr, ARRAYLEN(arr));

    PrintAndLogEx(INFO, " Before:  %s", sprint_hex(arr, 8));
    descramble(arr, ARRAYLEN(arr));
    PrintAndLogEx(INFO, " After :  %s", sprint_hex(arr, 8));

    // 4bit region code
    uint8_t rc = (arr[3] & 0x0E) >> 1;

    // 16bit FC
    uint16_t fc = (arr[5] & 0x0F) << 12 | arr[1] << 4 | ((arr[7] >> 4) & 0x0F);

    // 24bit CN
    uint32_t cn = arr[0] << 16 | (arr[4] & 0x1F) << 11 | arr[2] << 3 | (arr[3] & 0xE0) >> 4;

    // 4bit issue level
    uint8_t il = arr[7] & 0x0F;

    PrintAndLogEx(SUCCESS, "GALLAGHER - Region: " _GREEN_("%u") " FC: " _GREEN_("%u") " CN: " _GREEN_("%u") " Issue Level: " _GREEN_("%u"), rc, fc, cn, il);
    PrintAndLogEx(SUCCESS, "   Printed: " _GREEN_("%C%u"), rc + 0x40, fc);
    PrintAndLogEx(SUCCESS, "   Raw: %08X%08X%08X", raw1, raw2, raw3);
    PrintAndLogEx(SUCCESS, "   CRC: %02X - %02X (%s)", crc, calc_crc, (crc == calc_crc) ? "ok" : "fail");
    return PM3_SUCCESS;
}

static int CmdGallagherDemod(const char *Cmd) {
    CLIParserContext *ctx;
    CLIParserInit(&ctx, "lf gallagher demod",
                  "Try to find GALLAGHER preamble, if found decode / descramble data",
                  "lf gallagher demod"
                 );

    void *argtable[] = {
        arg_param_begin,
        arg_param_end
    };
    CLIExecWithReturn(ctx, Cmd, argtable, true);
    CLIParserFree(ctx);
    return demodGallagher(true);
}

static int CmdGallagherReader(const char *Cmd) {
    CLIParserContext *ctx;
    CLIParserInit(&ctx, "lf gallagher reader",
                  "read a GALLAGHER tag",
                  "lf gallagher reader -@   -> continuous reader mode"
                 );

    void *argtable[] = {
        arg_param_begin,
        arg_lit0("@", NULL, "optional - continuous reader mode"),
        arg_param_end
    };
    CLIExecWithReturn(ctx, Cmd, argtable, true);
    bool cm = arg_get_lit(ctx, 1);
    CLIParserFree(ctx);

    do {
        lf_read(false, 4096 * 2 + 20);
        demodGallagher(!cm);
    } while (cm && !kbd_enter_pressed());
    return PM3_SUCCESS;
}

static int CmdGallagherClone(const char *Cmd) {

    CLIParserContext *ctx;
    CLIParserInit(&ctx, "lf gallagher clone",
                  "clone a GALLAGHER tag to a T55x7, Q5/T5555 or EM4305/4469 tag.",
                  "lf gallagher clone --raw 0FFD5461A9DA1346B2D1AC32\n"
                  "lf gallagher clone --q5 --raw 0FFD5461A9DA1346B2D1AC32 -> encode for Q5/T5555 tag\n"
                  "lf gallagher clone --em --raw 0FFD5461A9DA1346B2D1AC32 -> encode for EM4305/4469"
                 );

    void *argtable[] = {
        arg_param_begin,
        arg_str1("r", "raw", "<hex>", "raw hex data. 12 bytes max"),
        arg_lit0(NULL, "q5", "optional - specify writing to Q5/T5555 tag"),
        arg_lit0(NULL, "em", "optional - specify writing to EM4305/4469 tag"),
        arg_param_end
    };
    CLIExecWithReturn(ctx, Cmd, argtable, false);

    int raw_len = 0;
    // skip first block,  3*4 = 12 bytes left
    uint8_t raw[12] = {0};
    CLIGetHexWithReturn(ctx, 1, raw, &raw_len);
    bool q5 = arg_get_lit(ctx, 2);
    bool em = arg_get_lit(ctx, 3);
    CLIParserFree(ctx);

    if (q5 && em) {
        PrintAndLogEx(FAILED, "Can't specify both Q5 and EM4305 at the same time");
        return PM3_EINVARG;
    }

    uint32_t blocks[4];
    for (uint8_t i = 1; i < ARRAYLEN(blocks); i++) {
        blocks[i] = bytes_to_num(raw + ((i - 1) * 4), sizeof(uint32_t));
    }

    //Pac - compat mode, NRZ, data rate 40, 3 data blocks
    blocks[0] = T55x7_MODULATION_MANCHESTER | T55x7_BITRATE_RF_32 | 3 << T55x7_MAXBLOCK_SHIFT;
    char cardtype[16] = {"T55x7"};
    // Q5
    if (q5) {
        blocks[0] = T5555_FIXED | T5555_MODULATION_MANCHESTER | T5555_SET_BITRATE(32) | 3 << T5555_MAXBLOCK_SHIFT;
        snprintf(cardtype, sizeof(cardtype), "Q5/T5555");
    }

    // EM4305
    if (em) {
        blocks[0] = EM4305_GALLAGHER_CONFIG_BLOCK;
        snprintf(cardtype, sizeof(cardtype), "EM4305/4469");
    }

    PrintAndLogEx(INFO, "Preparing to clone Gallagher to " _YELLOW_("%s") " with raw hex", cardtype);
    print_blocks(blocks,  ARRAYLEN(blocks));

    int res;
    if (em) {
        res = em4x05_clone_tag(blocks, ARRAYLEN(blocks), 0, false);
    } else {
        res = clone_t55xx_tag(blocks, ARRAYLEN(blocks));
    }
    PrintAndLogEx(SUCCESS, "Done");
    PrintAndLogEx(HINT, "Hint: try " _YELLOW_("`lf gallagher reader`") " to verify");
    return res;
}

static int CmdGallagherSim(const char *Cmd) {

   CLIParserContext *ctx;
    CLIParserInit(&ctx, "lf gallagher sim",
                  "Enables simulation of GALLAGHER card with specified card number.\n"
                  "Simulation runs until the button is pressed or another USB command is issued.\n",
                  "lf gallagher sim --raw 0FFD5461A9DA1346B2D1AC32"
                 );

    void *argtable[] = {
        arg_param_begin,
        arg_str1("r", "raw", "<hex>", "raw hex data. 12 bytes max"),
        arg_param_end
    };
    CLIExecWithReturn(ctx, Cmd, argtable, false);
    int raw_len = 0;
    // skip first block,  3*4 = 12 bytes left
    uint8_t raw[12] = {0};
    CLIGetHexWithReturn(ctx, 1, raw, &raw_len);
    CLIParserFree(ctx);

    // ASK/MAN sim.
    PrintAndLogEx(SUCCESS, "Simulating Gallagher - raw " _YELLOW_("%s"), sprint_hex_inrow(raw, sizeof(raw)));

    uint8_t bs[sizeof(raw) * 8];
    bytes_to_bytebits(raw, sizeof(raw), bs);

    lf_asksim_t *payload = calloc(1, sizeof(lf_asksim_t) + sizeof(bs));
    payload->encoding = 1;
    payload->invert = 0;
    payload->separator = 0;
    payload->clock = 32;
    memcpy(payload->data, bs, sizeof(bs));

    clearCommandBuffer();
    SendCommandNG(CMD_LF_ASK_SIMULATE, (uint8_t *)payload,  sizeof(lf_asksim_t) + sizeof(bs));
    free(payload);

    PacketResponseNG resp;
    WaitForResponse(CMD_LF_ASK_SIMULATE, &resp);

    PrintAndLogEx(INFO, "Done");
    if (resp.status != PM3_EOPABORTED)
        return resp.status;

    return PM3_SUCCESS;
    return PM3_SUCCESS;
}

static command_t CommandTable[] = {
    {"help",   CmdHelp,            AlwaysAvailable, "This help"},
    {"demod",  CmdGallagherDemod,  AlwaysAvailable, "Demodulate an GALLAGHER tag from the GraphBuffer"},
    {"reader", CmdGallagherReader, IfPm3Lf,         "Attempt to read and extract tag data from the antenna"},
    {"clone",  CmdGallagherClone,  IfPm3Lf,         "clone GALLAGHER tag to T55x7"},
    {"sim",    CmdGallagherSim,    IfPm3Lf,         "simulate GALLAGHER tag"},
    {NULL, NULL, NULL, NULL}
};

static int CmdHelp(const char *Cmd) {
    (void)Cmd; // Cmd is not used so far
    CmdsHelp(CommandTable);
    return PM3_SUCCESS;
}

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

// find Gallagher preamble in already demoded data
int detectGallagher(uint8_t *dest, size_t *size) {
    if (*size < 96) return -1; //make sure buffer has data
    size_t startIdx = 0;
    uint8_t preamble[] = { 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0 };
    if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
        return -2; //preamble not found

    if (*size != 96) return -3; //wrong demoded size
    //return start position
    return (int)startIdx;
}