/*
 * buildtnco - helper for nLaunch
 *
 * Copyright (C) 2012-2013 nLaunch team
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
 */

#include <stdio.h>

static const unsigned char part1[] = {
    0x54, 0x49, 0x2d, 0x4e, 0x73, 0x70, 0x69, 0x72, 0x65, 0x2e, 0x74, 0x6e, 0x63, 0x20, 0x31, 0x2e,
    0x31, 0x2e, 0x39, 0x31, 0x37, 0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x30, 0x20,
    0x30, 0x0a, 0x5f, 0x5f, 0x52, 0x45, 0x53, 0x5f, 0x5f, 0x20, 0x31, 0x2e, 0x31, 0x2e, 0x39, 0x31,
    0x37, 0x30, 0x20, 0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x30, 0x0a, 0x0a, 0x1a,
    0x50, 0x4b, 0x03, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

static const unsigned char part3[] = {
                                                                            0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x09, 0x00,
    0x00, 0xea, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x70, 0x11, 0xb0, 0x02, 0x82, 0x11
};

int main(int argc, char * argv[]) {
    FILE * input = fopen("nlaunch.tns", "rb");
    FILE * output1 = fopen("nlaunch.tno", "w+b");
    FILE * output2 = fopen("nlaunch.tnc", "w+b");
    long filesize;
    long padding;
    long i;
    if (input != NULL && output1 != NULL && output2 != NULL) {
        // Header
        fwrite(part1, sizeof(part1[0]), sizeof(part1)/sizeof(part1[0]), output1);
        fwrite(part1, sizeof(part1[0]), sizeof(part1)/sizeof(part1[0]), output2);

        // Retrieve the size of the payload.
        fseek(input, 0, SEEK_END);
        filesize = ftell(input);
        fseek(input, 0, SEEK_SET);

        // Second part: size bytes
        filesize += 0x1CA - 0x40 - 0x1E;
        padding = ((filesize + 0x100) & 0xFF00) - filesize;
        printf("Initial payload size is %ld (0x%lX), will add %ld (0x%lX) bytes of padding\n", filesize, filesize, padding, padding);
        fputc(0x00, output1);
        fputc(0x00, output2);
        fputc(((filesize + 0x100) & 0xFF00) >> 8, output1);
        fputc(((filesize + 0x100) & 0xFF00) >> 8, output2);
        filesize -= 0x1CA - 0x40 - 0x1E;

        // Smasher + padding
        fwrite(part3, sizeof(part3[0]), sizeof(part3)/sizeof(part3[0]), output1);
        fwrite(part3, sizeof(part3[0]), sizeof(part3)/sizeof(part3[0]), output2);
        for (i = 0; i < padding; i++) {
            fputc(0x00, output1);
            fputc(0x00, output2);
        }

        // Payload
        for (i = 0; i < filesize; i++) {
            int c = fgetc(input);
            fputc(c, output1);
            fputc(c, output2);
        }

        // Update leading metadata
        filesize = ftell(output1);
        fseek(output1, 23, SEEK_SET);
        fseek(output2, 23, SEEK_SET);
        fprintf(output1, "%8ld", filesize);
        fprintf(output2, "%8ld", filesize);

        fclose(input);
        fclose(output1);
        fclose(output2);
    }
    else {
        fprintf(stderr, "Couldn't open input file nlaunch.tns or output files nlaunch.tno/.tnc !\n");
    }
    return 0;
}