#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Pin
const int SWITCH_MASUK = 13;

// Slot kiri (HIGH = kosong)
const int SLOT_L1 = 6;
const int SLOT_L2 = 7;
const int SLOT_L3 = 8;

// Slot kanan (LOW = kosong)
const int SLOT_R1 = A1;
const int SLOT_R2 = A2;
const int SLOT_R3 = A3;

// LCD
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Status sebelumnya
int prevL1 = -1, prevL2 = -1, prevL3 = -1;
int prevR1 = -1, prevR2 = -1, prevR3 = -1;

// Timer
unsigned long startTime;
const unsigned long pantauDurasi = 10000;  // 10 detik

void setup() {
  Serial.begin(9600);
  lcd.init();
  lcd.backlight();

  pinMode(SWITCH_MASUK, INPUT);
  pinMode(SLOT_L1, INPUT);
  pinMode(SLOT_L2, INPUT);
  pinMode(SLOT_L3, INPUT);
  pinMode(SLOT_R1, INPUT);
  pinMode(SLOT_R2, INPUT);
  pinMode(SLOT_R3, INPUT);

  tampilkanSiap();
}

void loop() {
  if (digitalRead(SWITCH_MASUK) == HIGH) {
    tampilkanSlotKosong();
    startTime = millis();

    // Pantau selama 10 detik
    while (millis() - startTime < pantauDurasi) {
      pantauSlot();
      delay(100);  // periksa setiap 100ms
    }

    tampilkanSiap();  // kembali ke awal
  }
}

// --- LCD ---
void tampilkanSiap() {
  lcd.clear();
  lcd.setCursor(1, 0); lcd.print("SMART PARKING");
  lcd.setCursor(1, 1); lcd.print("TAB ACCES CARD");
}

void tampilkanSlotKosong() {
  lcd.clear();
  lcd.setCursor(1, 0); lcd.print("Slot Tersedia:");

  bool L1 = digitalRead(SLOT_L1) == HIGH;
  bool L2 = digitalRead(SLOT_L2) == HIGH;
  bool L3 = digitalRead(SLOT_L3) == HIGH;
  bool R1 = digitalRead(SLOT_R1) == LOW;
  bool R2 = digitalRead(SLOT_R2) == LOW;
  bool R3 = digitalRead(SLOT_R3) == LOW;

  lcd.setCursor(2, 1);
  lcd.print("L:");
  lcd.print(L1 ? "1" : "-");
  lcd.print(L2 ? "2" : "-");
  lcd.print(L3 ? "3" : "-");
  lcd.print(" R:");
  lcd.print(R1 ? "1" : "-");
  lcd.print(R2 ? "2" : "-");
  lcd.print(R3 ? "3" : "-");

  kirimStatusSlot();  // kirim awal
}

// --- Pantau perubahan slot ---
void pantauSlot() {
  int L1 = digitalRead(SLOT_L1) == LOW ? 1 : 0;
  int L2 = digitalRead(SLOT_L2) == LOW ? 1 : 0;
  int L3 = digitalRead(SLOT_L3) == LOW ? 1 : 0;
  int R1 = digitalRead(SLOT_R1) != LOW;
  int R2 = digitalRead(SLOT_R2) != LOW;
  int R3 = digitalRead(SLOT_R3) != LOW;

  if (L1 != prevL1 || L2 != prevL2 || L3 != prevL3 ||
      R1 != prevR1 || R2 != prevR2 || R3 != prevR3) {

    lcd.clear();
    lcd.setCursor(0, 0); lcd.print("Slot Terisi:");
    lcd.setCursor(0, 1);
    lcd.print("L:");
    lcd.print(L1 ? "1" : "-");
    lcd.print(L2 ? "2" : "-");
    lcd.print(L3 ? "3" : "-");
    lcd.print(" R:");
    lcd.print(R1 ? "1" : "-");
    lcd.print(R2 ? "2" : "-");
    lcd.print(R3 ? "3" : "-");

    kirimStatusSlot();

    prevL1 = L1; prevL2 = L2; prevL3 = L3;
    prevR1 = R1; prevR2 = R2; prevR3 = R3;
  }
}

// --- Kirim ke Serial (JSON) ---
void kirimStatusSlot() {
  int L1 = digitalRead(SLOT_L1) == LOW ? 1 : 0;
  int L2 = digitalRead(SLOT_L2) == LOW ? 1 : 0;
  int L3 = digitalRead(SLOT_L3) == LOW ? 1 : 0;
  int R1 = digitalRead(SLOT_R1) != LOW;
  int R2 = digitalRead(SLOT_R2) != LOW;
  int R3 = digitalRead(SLOT_R3) != LOW;

  Serial.print("{\"L1\":"); Serial.print(L1);
  Serial.print(",\"L2\":"); Serial.print(L2);
  Serial.print(",\"L3\":"); Serial.print(L3);
  Serial.print(",\"R1\":"); Serial.print(R1);
  Serial.print(",\"R2\":"); Serial.print(R2);
  Serial.print(",\"R3\":"); Serial.print(R3);
  Serial.println("}");
}