#include <LiquidCrystal_I2C.h>
#include <DHTesp.h>
#include <HTTPClient.h>
#include <WiFi.h>
#include <PubSubClient.h> // Include the MQTT library

#define LED_PIN 32
#define DHT_PIN 15
#define MOTION_PIN 12
LiquidCrystal_I2C lcd(0x27,20,4);  // set the LCD address to 0x27 for a 16 chars and 2 line display

int motion_detec = 0;
const char* ssid = "Wokwi-GUEST";
const char* pass = "";
const char* MQTT_BROKER = "broker.emqx.io"; // MQTT broker address
const char* clientID = "ujaisldaaasdfgh;laslksdja1";

// Parameters for using non-blocking delay
unsigned long previousMillis = 0;
const long interval = 1000;
String msgStr = "";      // MQTT message buffer
float temp, humid;

DHTesp dhtSensor;
WiFiClient wifiClient;
PubSubClient mqttClient(wifiClient);

void setup_wifi() {
  delay(10);
  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, pass);
  while(WiFi.status() != WL_CONNECTED){
    delay(100);
    Serial.println(".");
  }
  Serial.println("WiFi Connected!");
  Serial.println(WiFi.localIP());
  //config LED_PIN output
  pinMode(LED_PIN, OUTPUT);
  pinMode(DHT_PIN, INPUT);
  pinMode(MOTION_PIN, INPUT);

  //setup for serial communication
  Serial.begin(9600);
  Serial.println("ESP32 collecting sensors data");

  //Setup DHT to according PIN
  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);

  lcd.init(); // initialize the lcd 
  // Print a message to the LCD.
  lcd.backlight();
  lcd.setCursor(1,0);
  lcd.print("ESP32 collecting data ...");

  setup_wifi();
  mqttClient.setServer(MQTT_BROKER, 1883); // Connect to MQTT broker
  mqttClient.setCallback(mqttCallback); // Set the callback function for MQTT messages
  delay(1000);
}

void loop() {
  if (!mqttClient.connected()) {
    reconnect();
  }
  mqttClient.loop();
  unsigned long currentMillis = millis(); // Read current time
  if (currentMillis - previousMillis >= interval) { // If current time - last time > 5 sec
    previousMillis = currentMillis;
    lcd.clear();
    TempAndHumidity data = dhtSensor.getTempAndHumidity();
    temp = data.temperature;
    humid = data.humidity;
    lcd.setCursor(0,0);
    lcd.print("Temp: " + String(temp));
    lcd.setCursor(0,1);
    lcd.print("Humidity: " + String(humid) +"%");

    msgStr = String(temp) + "," + String(humid) + ",";
    byte arrSize = msgStr.length() + 1;
    char msg[arrSize];
    Serial.print("PUBLISH DATA: ");
    Serial.println(msgStr);
    msgStr.toCharArray(msg, arrSize);
    mqttClient.publish("sensor", msg);
    msgStr = "";
    delay(1);
  }
  //Turn on led if motion sensor return true
  // motion_detec = digitalRead(MOTION_PIN);

  // if(motion_detec == 1){
  //   digitalWrite(LED_PIN, true);
  //   Serial.println("Motion detected!");
  // }
  // else{
  //   digitalWrite(LED_PIN, false);
  // }
}
void reconnect() {
  while (!mqttClient.connected()) {
    if (mqttClient.connect(clientID)) {
      Serial.println("MQTT connected");
      mqttClient.subscribe("led");
      mqttClient.subscribe("sensor");
      Serial.println("Topic Subscribed");
    }
    else {
      Serial.print("failed, rc=");
      Serial.print(mqttClient.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);  // wait 5sec and retry
    }
  }
}


void mqttCallback(char* topic, byte* payload, unsigned int length) {
  String message;
  for (int i = 0; i < length; i++) {
    message += (char)payload[i];
  }
  
  if (String(topic) == "led") {
    Serial.println(message);
    if (message == "ON" || message == "on") {
      digitalWrite(LED_PIN, true);
    } else if (message == "OFF" || message == "off") {
      digitalWrite(LED_PIN, false);
    }
  }
}