chess-timer.ino

const int SECOND = 1000;
const int MINUTE = 60 * SECOND;
const int RESOLUTION = 1 * SECOND;
//const int EXTRA_TURN_TIME = SECOND;

const int GREEN = 0;
const int RED = 1;

const int DRY_RUN = 1; // Comment this whole line to enable gpio pins

void pinMode(int pin, int mode) {
  // noop
}

// Pin assignment
BTN_PLAYER_0 = 10
LED_0_GREEN = 13
LED_0_RED = 14

BTN_PLAYER_1 = 11
LED_1_GREEN = 15
LED_1_RED = 16

BTN_MODE_SELECT = 12

// Pin setuo
pinMode(BTN_PLAYER_0, INPUT)
pinMode(LED_0_GREEN, OUTPUT)
pinMode(LED_0_RED, OUTPUT)

pinMode(BTN_PLAYER_1, INPUT)
pinMode(LED_1_GREEN, OUTPUT)
pinMode(LED_1_RED, OUTPUT)

pinMode(BTN_MODE_SELECT, INPUT)

// Setup pins
const int GAME_TIME = 5 * MINUTE

int activePlayer = 0;
int timeLeft[] = { GAME_TIME, GAME_TIME };
boolean gameStarted = 0;

void playerLed(int player, int color, int state) {
  digitalWrite((player * 2) + color, state);
}

void turnComplete() {
  activePlayer ^= 1;
}

// Runs forever
void loop() {
  if (gameStarted) {
    
    // Game over ?
    if (timeLeft[activePlayer] <= 0) {
      gameStarted = false;
      int winner = activePlayer ^ 1;
      int loser = activePlayer;
      
      playerLed(winner, RED, LOW);
      playerLed(loser, GREEN, LOW);
      
      // Visualize winner and loser
      while (true) {
        playerLed(winner, GREEN, HIGH);
        playerLed(loser, RED, HIGH);
        delay(0.5 * SECOND);
        
        playerLed(winner, GREEN, LOW);
        playerLed(loser, RED, LOW);
        delay(0.5 * SECOND);
      }
    }
    
    // Countdown!
    timeLeft[activePlayer] -= RESOLUTION;
    delay(RESOLUTION);
  }
}