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

// Pin definitions
const int oilSensorPin = 34;   // Oil quality sensor (potentiometer)
#define ONE_WIRE_BUS 27        // DS18B20 sensor
const int yellowLedPin = 15;   // Yellow LED
const int redLedPin = 4;       // Red LED

// Initialize DS18B20 and LCDs
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);
LiquidCrystal_I2C mainDisplay(0x27, 16, 2); // Main display (I2C address 0x27)
LiquidCrystal_I2C dataDisplay(0x26, 16, 2); // Data display (I2C address 0x26)

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

  // Initialize sensors and LCDs
  sensors.begin();
  mainDisplay.init();
  mainDisplay.backlight();
  dataDisplay.init();
  dataDisplay.backlight();

  // Configure LED pins as outputs
  pinMode(yellowLedPin, OUTPUT);
  pinMode(redLedPin, OUTPUT);

  // Ensure LEDs are off initially
  digitalWrite(yellowLedPin, LOW);
  digitalWrite(redLedPin, LOW);

  Serial.println("Setup complete!");
}

void loop() {
  // Simulate oil quality
  int oilSensorValue = analogRead(oilSensorPin);
  float oilQuality = (oilSensorValue / 4095.0) * 100.0;

  // Read coolant temperature
  sensors.requestTemperatures();
  float coolantTemp = sensors.getTempCByIndex(0);
  
  // Handle invalid DS18B20 readings
  if (coolantTemp == DEVICE_DISCONNECTED_C || coolantTemp == -127.0) {
    Serial.println("DS18B20 not working. Using random temperature for debugging.");
    coolantTemp = random(20, 81); // Simulate random temperature for now
  }

  Serial.println("Oil Quality: " + String(oilQuality) + "%");
  Serial.println("Coolant Temp: " + String(coolantTemp) + "°C");

  // Indicators logic
  int issues = 0;
  if (oilQuality < 5.0) issues++;
  if (coolantTemp > 50.0) issues++;

  // Control LEDs and Main Display
  mainDisplay.clear();
  if (issues == 0) {
    mainDisplay.setCursor(0, 0);
    mainDisplay.print("System Normal");
    digitalWrite(yellowLedPin, LOW);
    digitalWrite(redLedPin, LOW);
  } else if (issues == 1) {
    mainDisplay.setCursor(0, 0);
    mainDisplay.print("Check System!");
    mainDisplay.setCursor(0, 1);
    mainDisplay.print("1 Issue Found");
    digitalWrite(yellowLedPin, HIGH);
    digitalWrite(redLedPin, LOW);
  } else {
    mainDisplay.setCursor(0, 0);
    mainDisplay.print("IMMEDIATE ATT!");
    mainDisplay.setCursor(0, 1);
    mainDisplay.print("2 Issues Found");
    digitalWrite(yellowLedPin, LOW);
    digitalWrite(redLedPin, HIGH);
  }

  // Update Data Display with Coolant Temp and Oil Quality
  dataDisplay.clear();
  dataDisplay.setCursor(0, 0);
  dataDisplay.print("Temp: ");
  dataDisplay.print(coolantTemp);
  dataDisplay.print("C");
  dataDisplay.setCursor(0, 1);
  dataDisplay.print("Oil: ");
  dataDisplay.print(oilQuality);
  dataDisplay.print("%");

  delay(15000); // Wait 15 seconds before next check
}