#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <LiquidCrystal_I2C.h>

// OLED water level display
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

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

// Ultrasonic pins
const int trigPin = 5;
const int echoPin = 18;

// Tank dimensions
const int tankHeight = 400; // cm

// LED pins
int ledPins[] = {13, 12, 14, 27}; // Green, Yellow, Red, White

// Buzzer pin
const int buzzerPin = 26;

// NTC temperature sensor pin
const int tempPin = 34;

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

  // LEDs
  for (int i = 0; i < 4; i++) {
    pinMode(ledPins[i], OUTPUT);
  }

  // Buzzer
  pinMode(buzzerPin, OUTPUT);

  // Ultrasonic
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);

  // OLED 
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("OLED failed");
    for (;;);
  }
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);

  // LCD init
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Temp Display Ready");
  delay(1000);
  lcd.clear();
}

void loop() {
  // Ultrasonic distance
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  long duration = pulseIn(echoPin, HIGH);
  int distance = duration * 0.034 / 2; // cm

  // Water level
  int waterLevel = tankHeight - distance;
  if (waterLevel < 0) waterLevel = 0;
  if (waterLevel > tankHeight) waterLevel = tankHeight;

  int percentage = map(waterLevel, 0, tankHeight, 0, 100);

  int adcValue = analogRead(tempPin);
  float temperature = (1.0 / ((log(1.0 / (4095.0 / adcValue - 1.0)) / 3950.0) + (1.0 / (25.0 + 273.15)))) - 273.15;

  for (int i = 0; i < 4; i++) digitalWrite(ledPins[i], LOW);
  if (percentage > 0 && percentage <= 25) {
    digitalWrite(ledPins[0], HIGH);
  } else if (percentage > 25 && percentage <= 50) {
    digitalWrite(ledPins[1], HIGH);
  } else if (percentage > 50 && percentage <= 75) {
    digitalWrite(ledPins[2], HIGH);
  } else if (percentage > 75 && percentage < 100) {
    digitalWrite(ledPins[3], HIGH);
  } else if (percentage >= 100) {
    bool blinkState = (millis() / 500) % 2;
    for (int i = 0; i < 4; i++) {
      digitalWrite(ledPins[i], blinkState);
    }
    digitalWrite(buzzerPin, blinkState);
  } else {
    digitalWrite(buzzerPin, LOW);
  }

  display.clearDisplay();
  display.setTextSize(1);
  display.setCursor(0, 0);
  display.println("Water Level Monitor");

  display.setTextSize(2);
  display.setCursor(0, 20);
  display.print("Level: ");
  display.print(percentage);
  display.println("%");

  display.display();

  
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temperature, 1);
  lcd.print(" C");
//if you ever read this then well all the sentences given below are taken from Differnt Songs
//just an Easter Egg
  lcd.setCursor(0, 1);
  if (temperature < 10) {
    lcd.print("Life's too Short");
  } else if (temperature <= 15) {
    lcd.print("This is all a situation");
  } else if (temperature <= 28) {
    lcd.print("The Best that Never was");
  } else if (temperature <= 36){
    lcd.print("No Rival")
  } else if (temperature <= 46){
    lcd.print("Everybody want some but can't handle when I brought 'em")
  } else if (temperature <= 58 ){
    lcd.print("Sheesh")
  } else if(temperature <=70 ){
    lcd.print("Too Hot, Too Hot")
  } else {
    lcd.print("Life's too short")
  }
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.print(" cm | Water: ");
  Serial.print(percentage);
  Serial.print("% | Temp: ");
  Serial.print(temperature);
  Serial.println(" C");

  delay(1000);
}