#define LANE1_GREEN 14
#define LANE1_YELLOW 3
#define LANE1_RED 4

#define LANE2_GREEN 5
#define LANE2_YELLOW 6
#define LANE2_RED 7

#define LANE3_GREEN 8
#define LANE3_YELLOW 9
#define LANE3_RED 10

#define LANE4_GREEN 11
#define LANE4_YELLOW 12
#define LANE4_RED 13

#define PED_RED 15
#define PED_GREEN 16
#define PED_BUTTON 2

volatile bool pedestrianRequest = false; // 보행자 버튼 상태 저장

void pedestrianInterrupt() {
    pedestrianRequest = true;  // 보행자 버튼이 눌리면 true 설정
}

void setup() {
    pinMode(LANE1_GREEN, OUTPUT);
    pinMode(LANE1_YELLOW, OUTPUT);
    pinMode(LANE1_RED, OUTPUT);
    
    pinMode(LANE2_GREEN, OUTPUT);
    pinMode(LANE2_YELLOW, OUTPUT);
    pinMode(LANE2_RED, OUTPUT);
    
    pinMode(LANE3_GREEN, OUTPUT);
    pinMode(LANE3_YELLOW, OUTPUT);
    pinMode(LANE3_RED, OUTPUT);
    
    pinMode(LANE4_GREEN, OUTPUT);
    pinMode(LANE4_YELLOW, OUTPUT);
    pinMode(LANE4_RED, OUTPUT);

    pinMode(PED_RED, OUTPUT);
    pinMode(PED_GREEN, OUTPUT);
    pinMode(PED_BUTTON, INPUT_PULLUP);

    attachInterrupt(digitalPinToInterrupt(PED_BUTTON), pedestrianInterrupt, FALLING); // 인터럽트 설정

    Serial.begin(9600);
}

void loop() {
    if (pedestrianRequest) {
        handlePedestrian();
    } else {
        trafficCycle();
    }
}

void trafficCycle() {
    // LANE 1 & 3 GREEN
    digitalWrite(LANE1_GREEN, HIGH);
    digitalWrite(LANE3_GREEN, HIGH);
    digitalWrite(LANE1_RED, LOW);
    digitalWrite(LANE3_RED, LOW);
    
    delay(5000);
    if (pedestrianRequest) return;

    // LANE 1 & 3 YELLOW
    digitalWrite(LANE1_GREEN, LOW);
    digitalWrite(LANE3_GREEN, LOW);
    digitalWrite(LANE1_YELLOW, HIGH);
    digitalWrite(LANE3_YELLOW, HIGH);
    
    delay(2000);
    if (pedestrianRequest) return;

    // LANE 1 & 3 RED
    digitalWrite(LANE1_YELLOW, LOW);
    digitalWrite(LANE3_YELLOW, LOW);
    digitalWrite(LANE1_RED, HIGH);
    digitalWrite(LANE3_RED, HIGH);

    delay(2000);
    if (pedestrianRequest) return;

    // LANE 2 & 4 GREEN
    digitalWrite(LANE2_GREEN, HIGH);
    digitalWrite(LANE4_GREEN, HIGH);
    digitalWrite(LANE2_RED, LOW);
    digitalWrite(LANE4_RED, LOW);
    
    delay(5000);
    if (pedestrianRequest) return;

    // LANE 2 & 4 YELLOW
    digitalWrite(LANE2_GREEN, LOW);
    digitalWrite(LANE4_GREEN, LOW);
    digitalWrite(LANE2_YELLOW, HIGH);
    digitalWrite(LANE4_YELLOW, HIGH);
    
    delay(2000);
    if (pedestrianRequest) return;

    // LANE 2 & 4 RED
    digitalWrite(LANE2_YELLOW, LOW);
    digitalWrite(LANE4_YELLOW, LOW);
    digitalWrite(LANE2_RED, HIGH);
    digitalWrite(LANE4_RED, HIGH);

    delay(2000);
}

void handlePedestrian() {
    Serial.println("🚶 Pedestrian request activated!");

    // 모든 차량을 정지 (RED ON)
    digitalWrite(LANE1_GREEN, LOW);
    digitalWrite(LANE1_YELLOW, LOW);
    digitalWrite(LANE1_RED, HIGH);

    digitalWrite(LANE2_GREEN, LOW);
    digitalWrite(LANE2_YELLOW, LOW);
    digitalWrite(LANE2_RED, HIGH);

    digitalWrite(LANE3_GREEN, LOW);
    digitalWrite(LANE3_YELLOW, LOW);
    digitalWrite(LANE3_RED, HIGH);

    digitalWrite(LANE4_GREEN, LOW);
    digitalWrite(LANE4_YELLOW, LOW);
    digitalWrite(LANE4_RED, HIGH);

    // 보행자 신호 켜기
    digitalWrite(PED_RED, LOW);
    digitalWrite(PED_GREEN, HIGH);

    delay(5000); // 보행자 신호 유지

    // 보행자 신호 끄기
    digitalWrite(PED_GREEN, LOW);
    digitalWrite(PED_RED, HIGH);

    pedestrianRequest = false; // 보행자 요청 해제
}