// ==== Pin Definitions ====
// Relay Control (Outputs)
const int FAN1_RELAY = 5;
const int FAN2_RELAY = 4;
const int LIGHT1_RELAY = 2;
const int LIGHT2_RELAY = 15;
const int LIGHT3_RELAY = 13;

// Manual Toggles (Inputs)
const int FAN1_BTN = 18;
const int FAN2_BTN = 19;
const int LIGHT1_BTN = 21;
const int LIGHT2_BTN = 22;
const int LIGHT3_BTN = 23;

// Sensor & Status
const int CURRENT_SENSOR = 34; // ACS712 analog in
const int STATUS_LED = 27;     // Heartbeat

// ==== State Tracking ====
bool f1_state = false;
bool f2_state = false;
bool l1_state = false;
bool l2_state = false;
bool l3_state = false;

// Button Last States (for debouncing/edge detection)
bool last_f1 = LOW, last_f2 = LOW, last_l1 = LOW, last_l2 = LOW, last_l3 = LOW;

unsigned long lastHeartbeat = 0;
unsigned long lastSerialPrint = 0;

void setup() {
  Serial.begin(115200);

  // Set Relay pins as outputs
  pinMode(FAN1_RELAY, OUTPUT);
  pinMode(FAN2_RELAY, OUTPUT);
  pinMode(LIGHT1_RELAY, OUTPUT);
  pinMode(LIGHT2_RELAY, OUTPUT);
  pinMode(LIGHT3_RELAY, OUTPUT);
  pinMode(STATUS_LED, OUTPUT);

  // Set Button pins as inputs with internal pulldowns
  pinMode(FAN1_BTN, INPUT_PULLDOWN);
  pinMode(FAN2_BTN, INPUT_PULLDOWN);
  pinMode(LIGHT1_BTN, INPUT_PULLDOWN);
  pinMode(LIGHT2_BTN, INPUT_PULLDOWN);
  pinMode(LIGHT3_BTN, INPUT_PULLDOWN);

  // Analog input for ACS712
  pinMode(CURRENT_SENSOR, INPUT);
}

// Function to handle toggling logic
void handleButton(int pin, bool &lastState, bool &relayState, int relayPin) {
  bool currentState = digitalRead(pin);
  
  // Detect low-to-high transition (button press)
  if (currentState == HIGH && lastState == LOW) {
    relayState = !relayState; // Toggle the state
    digitalWrite(relayPin, relayState ? HIGH : LOW);
    delay(50); // Simple debounce
  }
  lastState = currentState;
}

void loop() {
  // 1. Scan Inputs and Update Relays
  handleButton(FAN1_BTN, last_f1, f1_state, FAN1_RELAY);
  handleButton(FAN2_BTN, last_f2, f2_state, FAN2_RELAY);
  handleButton(LIGHT1_BTN, last_l1, l1_state, LIGHT1_RELAY);
  handleButton(LIGHT2_BTN, last_l2, l2_state, LIGHT2_RELAY);
  handleButton(LIGHT3_BTN, last_l3, l3_state, LIGHT3_RELAY);

  // 2. Handle Heartbeat LED (blinks every 500ms)
  if (millis() - lastHeartbeat >= 500) {
    lastHeartbeat = millis();
    digitalWrite(STATUS_LED, !digitalRead(STATUS_LED)); // Toggle LED status
  }

  // 3. Read Analog Sensor (simulating printing to serial every 2 seconds)
  if (millis() - lastSerialPrint >= 2000) {
    lastSerialPrint = millis();
    int sensorValue = analogRead(CURRENT_SENSOR);
    Serial.print("ACS712 Simulated Analog Value: ");
    Serial.println(sensorValue);
  }

  delay(10); // Yield slightly to prevent Watchdog Timer crashes
}