#include <PubSubClient.h>
#include "WiFi.h"
#include <DHT.h>
#include <LiquidCrystal_I2C.h>
#include <ArduinoJson.h>
const int dhtPin = 14;
const int triggerPin = 12;
const int echoPin = 27;
DHT dht(dhtPin, DHT22);
LiquidCrystal_I2C lcd(0x27, 20, 4);
DynamicJsonDocument doc(1024);
const char* mqttServer = "broker.hivemq.com";
int port = 1883;
char clientId[50];
const char* ssid = "Wokwi-GUEST";
int channel = 6;
const char* password = "";
WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  
  Serial.begin(115200);
  lcd.init();
  lcd.backlight();
  lcd.begin(20, 4);
dht.begin();
Serial.print("Connecting to ");
  Serial.println(ssid);
  wifiConnect();
  pinMode(triggerPin, OUTPUT);
  pinMode(echoPin, INPUT_PULLUP);
  client.setServer(mqttServer, port);
  // client.setCallback(callback);
}
void loop() {

float humidity=dht.readHumidity();
// Read temperature as Celsius (the default)
float temperature = dht.readTemperature();
lcd.setCursor(0,0);
lcd.print("Humiditiy : "+String(humidity));
lcd.setCursor(0,1);
lcd.print("Temp  : "+String(temperature));
Serial.println("Humiditiy : "+String(humidity));
Serial.println("TEmp is : "+String(temperature));

lcd.setCursor(0,2);
digitalWrite(triggerPin, LOW);
delayMicroseconds(2);
digitalWrite(triggerPin, HIGH);
delayMicroseconds(10);
digitalWrite(triggerPin, LOW);
// Measure the echo time
float duration = pulseIn(echoPin, HIGH);
// Calculate the distance in centimeters
// distance=duration×0.034cm/μs/2
// 0.034 speed of sound in air
float distance = duration * 0.034 / 2;
lcd.print("Duration: " + String(duration)); //(char)223 = degree symbol
lcd.setCursor(0,3);
lcd.print("Distance: " + String(distance,0) + " cm");
String JsonData;
doc["Temperature"]=temperature;
doc["Humidity"]=humidity;
doc["Distance"]=distance;
doc["Feet"]=distance/30.48;
serializeJson(doc,JsonData);
Serial.println(JsonData);

//delay(1000);// Delay for readability
if (!client.connected())
  {
    mqttReconnect();
  }
  else
  {
    float temperature = dht.readTemperature();
    char tempstr[10];
    dtostrf(temperature,6,2,tempstr);

    client.publish("Temperature_75", JsonData.c_str());//topic,data
    //variable.c_str() -->str to const char
  }
  client.loop();
  delay(1000);
  
}
void wifiConnect() {
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
}
void mqttReconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    long r = random(1000);
    sprintf(clientId, "fcs-clientId-%ld", r);
    if (client.connect(clientId)) {
      Serial.print(clientId);
      Serial.println("connected");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}