#include <fstream.h>
#include <iostream.h>
#include <hash_map>



int isalpha(int value) {
  if(value == 0x5b) return 1;
  if(value == '\n') return 1;
  if(value == '#') return 1;
  if(value == ' ') return 1;
  if(value < 'A') return 0;
  if(value > 'z') return 0;

  if( (value > 'Z') && (value < 'a') ) return 0;
  return true;
}

struct eqint {
  bool operator()(const char c1, const char c2) {
    if(c1 == c2) return true;
    return false;
  }
};



int hextoi(char* input) {
  // Convert a 2 character hex string to an int.

  int total = 0;
  if( ('a' <= input[0]) && (input[0] <= 'f') ) {
    total += (16 * (input[0] - 'a' + 10));
  } else {
    total += (16 * (input[0] - '0'));
    cout << dec << total << endl;
  }
  if( ('a' <= input[1]) && (input[1] <= 'f') ) {
    total += (input[1] - 'a' + 10);
  } else {
    total += (input[1] - '0');
  }

  cout << input << " is " << total << endl;

  return total;
}

int main(int argc, char** argv) {

  ifstream file(argv[1]);
  if(!file) {
    cerr << "can't open " << argv[1] << "." << endl;
    exit(1);
  }

  hash_map<char, char, hash<int>, eqint> characters;
  char buffer[1024];

  file.read(buffer, 1024);

  int size = file.gcount();

  cout << "Read " << size << " bytes." << endl;

  for(int count = 0;count < 532;count++) {

    char value = buffer[count];
    if(characters.end() == characters.find(value)) {
      characters[value] = value;
    }
  }

  while(1) {

    hash_map<char, char, hash<int>, eqint>::iterator itr = characters.begin();
    hash_map<char, char, hash<int>, eqint>::iterator stop = characters.end();

    for(;itr != stop;itr++) {
      cout << hex << itr->first << " maps to " << itr->second << "." << endl;
    }

    for(int count = 0;count < size;count++) {
      char value = buffer[count];
      char map_value = characters[value];
 
      if(isalpha(characters[value]) || ('\n' == characters[value])) {
	cout << characters[value];
      } else {
	//	cout << (char) characters[value] << " is not printable. " << endl;

	cout << "*";
      }
    }

    char inbuf[1024];
    cin.getline(inbuf, 1024, '\n');
    int from = hextoi(strtok(inbuf, " \t\r\n"));
    int to = hextoi(strtok(NULL, " \t\r\n"));

    characters[from] = to;

    cout << "Setting " << hex << from << " to " << to << dec << "." << endl;

  }
}