/*
 * Copyright 2004,2005,2016 Ronald S. Burkey <info@sandroid.org>
 *
 * This file is part of yaAGC.
 *
 * yaAGC is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * yaAGC 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 yaAGC; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Filename:    webb2burkey-rope.c
 * Purpose:	A utility program that converts an AGC core-rope
 *              from Julian Webb's format to the Virtual AGC
 *              (Ron Burkey's) format, and vice-versa.
 * Contact:	Ron Burkey <info@sandroid.org>
 * Website:	www.ibiblio.org/apollo/index.html
 * Mod history:	07/16/04 RSB	Began.
 *              05/14/05 RSB	Fixed website references.
 *              09/29/16 RSB    Now that there are Block 2 programs with
 *                              less than 044 banks (such as Aurora 12),
 *                              had to modify this program to gracefully
 *                              accept that condition.  Also, had to
 *                              fix the format of this file-header, which
 *                              had become messed up.
 *
 * The point of this utility is that it allows AGC programs assembled with
 * Julian Webb's assembler to be run on yaAGC (if prefer my sim to Julian's),
 * and AGC programs assembled with yaYUL to be run on Julian Webb's AGC sim
 * (if you prefer Julian's sim to mine).
 *
 * The format of a yaAGC rope is defined in www.ibiblio.org/apollo/developer.html.
 * The format of Webb's rope format is as follows:  The files are ASCII,
 * with one line for each memory location.  The lines are arranged in order
 * of increasing addresses: i.e., Bank 0 offset 0 is first and Bank 43 (octal)
 * offset 1777 (octal) is last.  Each line consists of a comma-separated
 * pair of decimal numbers.  The SECOND number is the value stored at the
 * location.  The FIRST number represents the address, but is mutated as
 * follows:  first the numbers 4096 through 6143 are used, then the numbers
 * 2048 through 4095 are used, and finally the numbers 8192 through 40959
 * are used.  (No, 0-2047 and 6144-8191 are not used.)
 */

//#define VERSION(x) #x
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

// Data is read into this array, and then it is written out again.
static unsigned Rope[044][02000] =
  {
    { 0 } };

static int endOfFile = 0;
static int
getByte(FILE *fin)
{
  int b;
  if (endOfFile)
    b = 0;
  else
    {
      b = fgetc(fin);
      if (b == EOF)
        {
          fprintf(stderr, "File ended prematurely, after %ld bytes.\n",
              ftell(fin));
          endOfFile = 1;
          b = 0;
        }
    }
  return (b);
}

int
main(int argc, char *argv[])
{
  int i, j, FromWebb = 0, RetVal = 1;
  char *InFile = NULL, *OutFile = NULL;
  FILE *fin = NULL, *fout = NULL;
  int Bank, Address;
  unsigned Value;

  printf("(c)2004,2005,2016 Ronald S. Burkey, ver " NVER
  ", built " __DATE__ "\n");
  printf(
      "Refer to http://www.ibiblio.org/apollo/index.html for more information.\n");

  //----------------------------------------------------------------------
  // Parse the command-line.
  for (i = 1; i < argc; i++)
    {
      if (!strcmp(argv[i], "--help") || !strcmp(argv[i], "/?"))
        {
          printf("USAGE:\n"
              "\twebb2burkey-rope [OPTIONS] Infile Outfile\r\n"
              "By default, the InFile is in Virtual AGC (Burkey)\r\n"
              "format and the OutFile is in Webb format.  Available\r\n"
              "OPTIONS are:\r\n"
              "--help       Display this menu.\r\n"
              "--from-webb  Convert to Virtual AGC (Burkey) format\r\n"
              "             from Webb format.\r\n");
          return (0);
        }
      else if (!strcmp(argv[i], "--from-webb"))
        FromWebb = 1;
      else if (argv[i][0] == '-')
        {
          printf("Unknown option \"%s\".\r\n", argv[i]);
          return (1);
        }
      else if (InFile == NULL)
        InFile = argv[i];
      else if (OutFile == NULL)
        OutFile = argv[i];
      else
        {
          printf("Unknown stuff on command line: \"%s\".\r\n", argv[i]);
          return (1);
        }
    }
  if (OutFile == NULL)
    {
      printf("Not enough files specified on command line.\r\n");
      return (1);
    }
  if (FromWebb)
    {
      fin = fopen(InFile, "r");
      fout = fopen(OutFile, "wb");
    }
  else
    {
      fin = fopen(InFile, "rb");
      fout = fopen(OutFile, "w");
    }
  if (fin == NULL)
    printf("Cannot open the input file.\r\n");
  if (fout == NULL)
    printf("Cannot create the output file.\r\n");
  if (fin == NULL || fout == NULL)
    goto Error;

  //----------------------------------------------------------------------
  // Read the input file.
  if (FromWebb)
    {
      for (i = Bank = Address = 0; i < 36864; i++)
        {
          if (2 != fscanf(fin, "%d,%u", &j, &Value))
            {
              printf("Corrupted input line or premature end of file.\r\n");
              goto Error;
            }
          Rope[Bank][Address] = Value;
          Address++;
          if (Address >= 02000)
            {
              Address = 0;
              Bank++;
            }
        }
    }
  else
    {
      for (Bank = 2; Bank < 044;)
        {
          for (Address = 0; Address < 02000; Address++)
            {
              int b;
              b = getByte(fin);
              if (b == EOF)
                {
                  printf("File-read error.\r\n");
                  goto Error;
                }
              Value = (b << 7) & 077600;
              b = getByte(fin);
              if (b == EOF)
                {
                  printf("File-read error.\r\n");
                  goto Error;
                }
              Value |= (b >> 1) & 0177;
              Rope[Bank][Address] = Value;
            }
          // Next bank.
          if (Bank == 2)
            Bank = 3;
          else if (Bank == 3)
            Bank = 0;
          else if (Bank == 0)
            Bank = 1;
          else if (Bank == 1)
            Bank = 4;
          else
            Bank++;
        }
    }

  //----------------------------------------------------------------------
  // Write the output file.
  if (FromWebb)
    {
      for (Bank = 2; Bank < 044;)
        {
          for (Address = 0; Address < 02000; Address++)
            {
              if (EOF == fputc(Rope[Bank][Address] >> 7, fout))
                {
                  printf("Write error. (Disk full?)\r\n");
                  goto Error;
                }
              if (EOF == fputc(Rope[Bank][Address] << 1, fout))
                {
                  printf("Write error. (Disk full?)\r\n");
                  goto Error;
                }
            }
          // Next bank.
          if (Bank == 2)
            Bank = 3;
          else if (Bank == 3)
            Bank = 0;
          else if (Bank == 0)
            Bank = 1;
          else if (Bank == 1)
            Bank = 4;
          else
            Bank++;
        }
    }
  else
    {
      for (i = 4096, Bank = 0; Bank < 044; Bank++)
        {
          for (Address = 0; Address < 02000; Address++)
            {
              fprintf(fout, "%d,%u\r\n", i, Rope[Bank][Address]);
              i++;
              if (i == 6144)
                i = 2048;
              else if (i == 4096)
                i = 8192;
            }
        }
    }

  //----------------------------------------------------------------------
  // All done.
  RetVal = 0;
  Error: if (fin != NULL)
    fclose(fin);
  if (fout != NULL)
    fclose(fout);
  return (RetVal);
}