/*
 * CMD2BIN
 * A tool for converting executable FLEX CMD files to binary files.
 * By Daniel Tufvesson 2015
 */
#include <stdlib.h>
#include <stdio.h>

#define false 0
#define true 1

int main(int argc, char **argv){
  FILE *flxFile;
  FILE *binFile;

  unsigned short address, next_address;
  unsigned char length, data;
  unsigned int addressLo = 0x0000, addressHi = 0xFFFF, first_run = true;

  if(argc < 3){
    printf("Usage: %s <infile.cmd> <outfile.bin> [start address] [stop address]\n",argv[0]);
    exit(0);
  }

  // Open files
  if( (flxFile = fopen( argv[1], "rb")) == NULL ){
    printf("Unable to open source file\n");
    exit(-1);
  }
  if( (binFile = fopen( argv[2], "wb")) == NULL ){
    printf("Unable to open destination file\n");
    exit(-1);
  }

  // Read start and stop addresses
  if(argc == 5){
    sscanf(argv[3], "%x", &addressLo);
    sscanf(argv[4], "%x", &addressHi);
  }

  // Read loop
  printf("Converting %04X to %04X\n", addressLo, addressHi);
  while(!feof(flxFile)){
    while(!feof(flxFile) && (data = fgetc(flxFile)) == 0); // Skip over chunks of zeroes
    if(data != 0x02) break; // Exit on unknown chunk ID
    // Read chunk header
    data = fgetc(flxFile); //Address MSB
    address = data << 8; //Shift one byte
    data = fgetc(flxFile); //Address LSB
    address = address | data;
    length = fgetc(flxFile); //Length
    if(first_run){
      next_address = address;
    }
    // Only print the chunks we write
    if(address >= addressLo && address <= addressHi){
      if(address != next_address & !first_run)
	printf("\n");
      printf("\nAddress: %04X-%04X  Length: %03d",address,address+length-1, length);
      first_run = false;
      next_address = address+length;
    }
    // Read chunk
    for(;length > 0; length--){
      data = fgetc(flxFile); //Data
      if(address >= addressLo && address <= addressHi)
	fputc(data,binFile);
    }
  }
  printf("\n\n");
  fclose(flxFile);
  fclose(binFile);
}