Pomodoro Timer: Update an in progress timer.

pomodoro.c

if (currentState != STATE_IDLE) {
  unsigned long timeNow = millis();
  if (timeNow - startTime >= MILLIS_IN_ONE_MIN) {
    minsRemaining--;

    if (minsRemaining == 0) {
      playTone(3);

      // Work out what state comes next...
      if (currentState == STATE_WORKING) {
        currIteration++;

        if (currIteration == 5) {
          currIteration = 1;
          minsRemaining = LONG_BREAK_MINS;
          currentState = STATE_BREAK;
          sprintf(statusBuf, "Long break...");
        } else {
          minsRemaining = SHORT_BREAK_MINS;
          currentState = STATE_BREAK;
          sprintf(statusBuf, "Short break...");
        }
      } else if (currentState == STATE_BREAK) {    
        minsRemaining = POMODORO_MINS;
        currentState = STATE_WORKING;
        sprintf(statusBuf, "Time to work... %d/4", currIteration);
      }   
    }

    drawScreen(statusBuf, minsRemaining);
    startTime = millis();     
  }
}