#include <Adafruit_GFX.h>
#include <Adafruit_PCD8544.h>

// Define pin connections for Nokia 5110 display
#define RST_PIN  D2
#define CE_PIN   D3
#define DC_PIN   D4
#define DIN_PIN  D11
#define CLK_PIN  D13

// Initialize display
Adafruit_PCD8544 display = Adafruit_PCD8544(CLK_PIN, DIN_PIN, DC_PIN, CE_PIN, RST_PIN);

// Multiplexor - corectat conform imaginii
const int S0 = 7;  // D7
const int S1 = 8;  // D8
const int S2 = 9;  // D9
const int S3 = 10; // D10
const int muxSIG = A0;
const int muxChannel = 0; // citim canalul 0

// Releu & LED
const int relayPin = 8;
const int ledPin = D6;  // LED pe pinul D6

// Timing
unsigned long previousBlink = 0;
bool ledState = false;

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

  pinMode(S0, OUTPUT);
  pinMode(S1, OUTPUT);
  pinMode(S2, OUTPUT);
  pinMode(S3, OUTPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(relayPin, OUTPUT);

  // Initialize the Nokia 5110 display
  display.begin();
  display.setContrast(50);
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(BLACK);

  display.setCursor(0, 0);
  display.println("Salut!");
  display.display();

  digitalWrite(relayPin, LOW); // start OFF
}

void selectMuxChannel(int channel) {
  digitalWrite(S0, channel & 1);
  digitalWrite(S1, (channel >> 1) & 1);
  digitalWrite(S2, (channel >> 2) & 1);
  digitalWrite(S3, (channel >> 3) & 1);
}

void loop() {
  // 1. Citim valoarea analogă de pe multiplexer canal 0
  selectMuxChannel(muxChannel);
  int sensorValue = analogRead(muxSIG);

  // 2. Decidem starea releului
  bool relayOn = sensorValue >= 500;
  digitalWrite(relayPin, relayOn ? HIGH : LOW);

  // 3. LED blink dacă releul e OFF
  if (!relayOn) {
    if (millis() - previousBlink >= 100) {
      ledState = !ledState;
      digitalWrite(ledPin, ledState);
      previousBlink = millis();
    }
  } else {
    digitalWrite(ledPin, LOW);
  }

  // 4. Afișăm pe display
  display.clearDisplay();
  display.setCursor(0, 0);
  display.print("Valoare: ");
  display.println(sensorValue);
  display.print("Releu: ");
  display.println(relayOn ? "ON" : "OFF");
  display.display();

  delay(10);
}