#include <OneWire.h>
#include <DallasTemperature.h>
#include <PubSubClient.h>
#include <WiFi.h>

// WiFi credentials
const char* ssid = "Wokwi-GUEST";
const char* password = "";

// MQTT broker settings
const char* mqtt_server = "broker.hivemq.com";
const char* mqtt_topic = "iot/sensor/data";
WiFiClient espClient;
PubSubClient client(espClient);

// Pin definitions
#define ONE_WIRE_BUS 12  // Pin connected to DS18B20
#define TRIG_PIN 26       // Pin connected to HC-SR04 TRIG
#define ECHO_PIN 25       // Pin connected to HC-SR04 ECHO
#define PH_PIN 34        // Pin connected to potentiometer for pH simulation
#define TDS_PIN 35      // Pin connected to potentiometer for flow simulation
#define Oksigen_PIN 32  // Pin connected to potentiometer for pressure simulation

// OneWire and DallasTemperature objects
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

void setup() {
  // Initialize Serial Monitor
  Serial.begin(9600);

  // Initialize DS18B20
  sensors.begin();

  // Initialize HC-SR04 pins
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  // Initialize sensor pins
  pinMode(PH_PIN, INPUT);
  pinMode(TDS_PIN, INPUT);
  pinMode(Oksigen_PIN, INPUT);

  // Connect to WiFi
  setup_wifi();

  // Set MQTT server
  client.setServer(mqtt_server, 1883);
}

void loop() {
  // Reconnect to MQTT broker if disconnected
  if (!client.connected()) {
    reconnect();
  }
  client.loop();

  // Read temperature from DS18B20
  sensors.requestTemperatures();
  float temperatureC = sensors.getTempCByIndex(0);

  // Read level from HC-SR04
  float distance = readDistance();

  // Read pH value from potentiometer
  int phValueRaw = analogRead(PH_PIN);
  float phValue = map(phValueRaw, 0, 1023, 0, 14);

  // Read flow value from potentiometer
  int TDSValueRaw = analogRead(TDS_PIN);
  float TDSValue = map(TDSValueRaw, 0, 1023, 0, 2000);

  // Read pressure value from potentiometer
  int OksigenValueRaw = analogRead(Oksigen_PIN);
  float OksigenValue = map(OksigenValueRaw, 0, 1023, 0, 20);

  // Create JSON payload
  String payload = "{";
  payload += "\"temperature\": " + String(temperatureC) + ", ";
  payload += "\"level\": " + String(distance) + ", ";
  payload += "\"ph\": " + String(phValue) + ", ";
  payload += "\"tds\": " + String(TDSValue) + ", ";
  payload += "\"oksigen\": " + String(OksigenValue);
  payload += "}";

  // Publish data to MQTT broker
  client.publish(mqtt_topic, payload.c_str());
  Serial.println(payload);

  delay(1000);
}

// Function to connect to WiFi
void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

// Function to reconnect to MQTT broker
void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    if (client.connect("ArduinoClient")) {
      Serial.println("connected");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(1000);
    }
  }
}

// Function to read distance from HC-SR04
float readDistance() {
  long duration;
  float distance;

  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2;
  return distance;
}