#include <LiquidCrystal_I2C.h>
// Pin definitions
#define BTN_1_PIN 2
#define BTN_2_PIN 3
#define BTN_3_PIN 4
#define BTN_4_PIN 5
#define BTN_ENTER_PIN A0

#define LED_R1_PIN 13
#define LED_B1_PIN 12
#define LED_R2_PIN 11
#define LED_B2_PIN 10
#define LED_R3_PIN 9
#define LED_B3_PIN 8
#define LED_R4_PIN 7
#define LED_B4_PIN 6

LiquidCrystal_I2C lcd(0x27,16,2);

// Game variables
char guess[5] = "0000";
char* history[] = {
  "3222"
};
int history_index = 0;
int current_digit = 0;
bool game_over = false;

// Function declarations
void setup();
void loop();
void generate_code(bool repeat, int length, char* code);
void get_score(const char* secret, const char* guess, int* peg_a, int* peg_b);
void turn_off_leds();
void render_leds(int peg_a, int peg_b);
void render_history(const char* secret, char** history, int entry);
void play_game(const char* secret);
void update_display();

void setup() {
  Serial.begin(9600);
  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Welcome to MasterMind");
  lcd.setCursor(0, 1);
  lcd.print("Your goal is to guess my secret combination.");
  delay(2000);
  
  // Initialize pins
  pinMode(BTN_1_PIN, INPUT_PULLUP);
  pinMode(BTN_2_PIN, INPUT_PULLUP);
  pinMode(BTN_3_PIN, INPUT_PULLUP);
  pinMode(BTN_4_PIN, INPUT);
  pinMode(BTN_ENTER_PIN, INPUT);

  pinMode(LED_R1_PIN, OUTPUT);
  pinMode(LED_B1_PIN, OUTPUT);
  pinMode(LED_R2_PIN, OUTPUT);
  pinMode(LED_B2_PIN, OUTPUT);
  pinMode(LED_R3_PIN, OUTPUT);
  pinMode(LED_B3_PIN, OUTPUT);
  pinMode(LED_R4_PIN, OUTPUT);
  pinMode(LED_B4_PIN, OUTPUT);

  turn_off_leds();

  // Generate secret code
  char* code = NULL;
  code = generate_code(true, 8);
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("I am thinking a number: ");
  lcd.setCursor(0, 1); 

  // Start the game
  play_game(code);
}
void turn_off_leds() {
  digitalWrite(LED_R1_PIN, LOW);
  digitalWrite(LED_B1_PIN, LOW);
  digitalWrite(LED_R2_PIN, LOW);
  digitalWrite(LED_B2_PIN, LOW);  
  digitalWrite(LED_R3_PIN, LOW);
  digitalWrite(LED_B3_PIN, LOW);
  digitalWrite(LED_R4_PIN, LOW);
  digitalWrite(LED_B4_PIN, LOW);
}
void render_leds(int peg_a, int peg_b){
  turn_off_leds();
  int red_leds[] = {LED_R1_PIN, LED_R2_PIN, LED_R3_PIN, LED_R4_PIN};
  int blue_leds[] = {LED_B1_PIN, LED_B2_PIN, LED_B3_PIN, LED_B4_PIN};
  for (int i = 0; i < peg_a; i++){
    digitalWrite(red_leds[i], HIGH);
  }
  for (int i = 0; i < peg_b; i++){
    digitalWrite(blue_leds[i], HIGH);
  }
}
void get_score(const char* secret, const char* guess, int* peg_a, int* peg_b){
  *peg_a = 0;
  *peg_b = 0;
  for (int i = 0; i < 4; i++){
    if (secret[i] == guess[i]){
      (*peg_a)++;
    }
    else{
      for (int j = 0; j < 4; j++){
        if (secret[i] == guess[j]){
          (*peg_b)++;
          break;
        }
      }
    }
  }
}
void play_game(const char* secret){
  while (game_over == false){
    update_display();
    while (digitalRead(BTN_1_PIN) == HIGH && digitalRead(BTN_2_PIN) == HIGH && digitalRead(BTN_3_PIN) == HIGH && digitalRead(BTN_4_PIN) == HIGH && digitalRead(BTN_ENTER_PIN) == HIGH){
      // Wait for any button to be pressed
    }   
    if (digitalRead(BTN_1_PIN) == LOW){
      guess[current_digit] = (guess[current_digit] - '0' + 1) % 10 + '0';
    }
    if (digitalRead(BTN_2_PIN) == LOW){
      guess[current_digit] = (guess[current_digit] - '0' + 9) % 10 + '0';
    }
    if (digitalRead(BTN_3_PIN) == LOW){
      current_digit = (current_digit + 1) % 4;
    }
    if (digitalRead(BTN_4_PIN) == LOW){
      current_digit = (current_digit + 3) % 4;
    }
    if (digitalRead(BTN_ENTER_PIN) == LOW){
      int peg_a, peg_b;
      get_score(secret, guess, &peg_a, &peg_b);
      render_leds(peg_a, peg_b);
      for (int i = 0; i < 4; i++){
        history[history_index][i] = guess[i];
      }
      history[history_index][4] = '\0';
      history_index++;
      if (peg_a == 4){
        game_over = true;
        lcd.clear();
        render_history(secret, history, history_index);
        lcd.setCursor(0, 1);
        lcd.print("Well done! You win in ");
        lcd.print(history_index);
        lcd.print(" guesses!");
        while (digitalRead(BTN_1_PIN) == HIGH && digitalRead(BTN_2_PIN) == HIGH && digitalRead(BTN_3_PIN) == HIGH && digitalRead(BTN_4_PIN) == HIGH && digitalRead(BTN_ENTER_PIN) == HIGH){
          // Wait for any button to be pressed
        }
        game_over = false;
        history_index = 0;
        turn_off_leds();
        current_digit = 0;
        for (int i = 0; i < 4; i++){
          guess[i] = '0';
        }
        return;
      }
      if (history_index == 10){
        game_over = true;
        lcd.clear();
        render_history(secret, history, history_index);
        lcd.setCursor(0, 1);
        lcd.print("Game over! My secret was ");
        lcd.print(secret);
        while (digitalRead(BTN_1_PIN) == HIGH && digitalRead(BTN_2_PIN) == HIGH && digitalRead(BTN_3_PIN) == HIGH && digitalRead(BTN_4_PIN) == HIGH && digitalRead(BTN_ENTER_PIN) == HIGH){
          // Wait for any button to be pressed
        }   
        game_over = false;
        history_index = 0;
        turn_off_leds();
        current_digit = 0;
        for (int i = 0; i < 4; i++){
          guess[i] = '0';
        }
      }

    }
  }
}
void loop() {

}

char* generate_code(bool repeat, int length) {
  randomSeed(analogRead(0));
  if (length < 1){
    return NULL;
  }
  if (repeat == false && length > 10){
    return NULL;
  }
  char* code = (char*)malloc(length+1);
  for (int i = 0; i < length; i++){
    code[i] = random(10) + '0';
    if (repeat == false){
      for (int j = 0; j < i; j++){
        if (code[i] == code[j]){
          i--;
          break;
        }
      }
    }
  }
  code[length] = '\0';
  return code;


}
void render_history(const char* secret, char** history, int entry){
  for (int i = 0; i < entry; i++){
    int peg_a, peg_b;
    get_score(secret, history[i], &peg_a, &peg_b);
    lcd.print(i+1);
    lcd.print(": ");
    lcd.print(history[i]);
    lcd.print(" ");
    for (int j = 0; j < peg_a; j++){
      lcd.print("R");
    }
    for (int j = 0; j < peg_b; j++){
      lcd.print("B");
    }
    lcd.print("\n");
  }
}
void update_display(){
  lcd.clear();
  render_history(guess, history, history_index);
  lcd.print("Your guess: ");
  lcd.print(guess);
}