#include <iostream>
using namespace std;

#include "digit.h"
#include "digitdata.h"

Digit::Digit()
{
  setdigit(0);
}

Digit::Digit(int n)
{
  setdigit(n);
}

Digit::~Digit()
{ }

int Digit::getvalue()
{
  return value;
}

void Digit::setdigit(int n)
{
  setvalue(n);
  setgrid(n);
}

void Digit::operator= (int n)
{
  setdigit(n);
}

void Digit::operator+= (Digit d)
{
  *this = *this + d;
}

void Digit::operator-= (Digit d)
{
  *this = *this - d;
}

Digit Digit::operator+ (Digit d)
{
  Digit res;
  int n;

  n = value + d.value;
  if(n >= 10) {
    n -= 10;
    cout << "(warning: addition overflow)\n";
  }

  res = n;

  return res;
}

Digit Digit::operator- (Digit d)
{
  Digit res;
  int n;
  
  n = value - d.value;
  if(n < 0) {
    n = - n;
    cout << "(warning: negative result)\n";
  }

  res = n;

  return res;
}

bool Digit::operator==(Digit d) { return (getvalue() == d.getvalue()); }
bool Digit::operator!=(Digit d) { return (getvalue() != d.getvalue()); }
bool Digit::operator<=(Digit d) { return (getvalue() <= d.getvalue()); }
bool Digit::operator<(Digit d)  { return (getvalue() < d.getvalue());  }
bool Digit::operator>=(Digit d) { return (getvalue() >= d.getvalue()); }
bool Digit::operator>(Digit d)  { return (getvalue() > d.getvalue());  }

Digit Digit::operator++()
{
  value++;
  if(value == 10) value = 0;
  setdigit(value);

  return *this;
}

Digit Digit::operator--()
{
  if(value == 0)
    value = 9;
  else
    value--;

  setdigit(value);

  return *this;
}


void Digit::setvalue(int n)
{
  value = n;
}

void Digit::setgrid(int n)
{
  for(int i = 0; i < ROWS; ++i)
    for(int j = 0; j < COLS ; ++j)
      grid[i][j] = number[n][i][j];
}

void Digit::display()
{
  cout << *this;
}

void Digit::showcell(int i, int j)
{
  cout << grid[i][j];
}

bool Digit::isvalid()
{
  return (value >=0 && value <=9);
}

ostream& operator<< (ostream& s, Digit& d)
{
  s << endl;
  s << "\t+--------+\n";
  for(int i = 0; i < ROWS; ++i) {
    s << "\t|";
    for(int j = 0; j < COLS ; ++j)
      d.showcell(i, j);
    s << "|" << endl;
  }
  s << "\t+--------+\n";
  s << endl;

  return s;
}

istream& operator>> (istream& s, Digit& d)
{
  int n;

  cout << "Enter an integer (0-9): ";
  s >> n;
  d = n;

  return s;
}