#include <Arduino.h>

#include <WiFi.h>
#include <Wire.h>
#include <ArduinoJson.h> //https://github.com/arduino-libraries/Arduino_JSON/tree/master
#include <PubSubClient.h> //https://github.com/knolleary/pubsubclient.git
#include <LiquidCrystal_I2C.h> //https://github.com/johnrickman/LiquidCrystal_I2C

LiquidCrystal_I2C LCD = LiquidCrystal_I2C(0x27, 16, 2);

//Thông số MQTT
//mqtt://testesp32-6h:[email protected]
const char *broker = "testesp32-6h.cloud.shiftr.io";
const char *topic_control = "/controller";
const char *topic_sensor = "/sensor";
const char *mqtt_user = "testesp32-6h";
const char *mqtt_pass = "gor5W7lwNvMOz8qB";
const char* mqtt_client_name = "ESP32 test";//tên client kết nối
#define PORT_MQTT 1883

WiFiClient wifiClient;
PubSubClient wifiMqtt(wifiClient);

// hàm sẽ được gọi khi có dữ liệu gửi đến esp qua mqtt
void mqttCallback(char* topic, byte* payload, unsigned int len) {
 Serial.print("Du lieu gui den [");
 Serial.print(topic);
 Serial.print("]: ");
 Serial.write(payload, len);
 Serial.println();
  String msg="";
  JsonDocument  myObject;
  for (int i = 0; i<len; ++i) {
    msg += (char)payload[i]; // typecast because String takes uint8_t as something else than char
  }

 //
 if (String(topic) == topic_control){
    deserializeJson(myObject, msg)
    Serial.println(myObject);
    DeserializationError error = deserializeMsgPack(myObject, input);
    if (error) {
      //đối tượng ko phải là kiểu json
      Serial.print("deserializeMsgPack() failed: ");
      Serial.println(error.f_str());
    }else{
      if (myObject.containsKey("type"))
      {
        Serial.print("myObject[\"type\"] = ");
        Serial.println(JSON.stringify(myObject["type"]));
      } else return;

      if (myObject.containsKey("data"))
      {
        Serial.print("myObject[\"data\"] = ");
        Serial.println(myObject["data"]);
      } else return;

      if (myObject["type"].as<String>().equals("\"LCD\""))
      {
        Serial.println(myObject["data"]);
        String dataS= myObject["data"].as<String>().substring(1, myObject["data"].as<String>().length()-1);
        int idx = dataS.indexOf(";");
        LCD.clear();
        if (idx == -1)
        {
          LCD.setCursor(0, 0);
          LCD.println(dataS);
        }
        else
        {
          LCD.setCursor(0, 0);
          LCD.println(dataS.substring(0, idx));
          LCD.setCursor(0, 1);
          LCD.println(dataS.substring(idx+1, dataS.length()));
        }
      }
    }
 }
}

// Hàm setup cho MQTT Client
void setupMQTT(PubSubClient *mqtt) {
  mqtt->setServer(broker, PORT_MQTT);
  mqtt->setCallback(mqttCallback);
}

bool isWifiConnected() {
  return (WiFi.status() == WL_CONNECTED);
}

// Hàm kết nối tới MQTT Broker
boolean connectMQTT(PubSubClient *mqtt) {
  Serial.print("Ket noi broker ");
  Serial.print(broker);
  boolean status = mqtt->connect(mqtt_client_name, mqtt_user, mqtt_pass);
  if (status == false) {
    Serial.println(" khong thanh cong!");
    return false;
  }
  Serial.println(" thanh cong!");

  mqtt->subscribe(topic_control);// Đăng ký nhận dữ liệu từ topic topic_relays
  return mqtt->connected();
}

// Hàm xử lý trong loop() dành cho MQTT Client dùng wifi
void mqttLoopWithWifi() {
  // Vì dùng wifi, nên nếu có kết nối GPRS với MQTT thì ngắt kết nối
  if (!wifiMqtt.connected()) {
    Serial.println("Ket noi MQTT voi Wifi");
    while ( (!wifiMqtt.connected()) && isWifiConnected()) {
      connectMQTT(&wifiMqtt);
      delay(5000);
    }
  } else
    wifiMqtt.loop();// Hàm xử lý của thư viện mqtt
}


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

  LCD.init();
  LCD.backlight();
  LCD.setCursor(0, 0);
  LCD.print("Connecting to ");
  LCD.setCursor(0, 1);
  LCD.print("WiFi ");

  // while (!Serial);
  //Bật wifi chế độ sta, kết nối với mạng internet
  WiFi.begin("Wokwi-GUEST", "", 6);
  while (WiFi.status() != WL_CONNECTED) {
      delay(100);
      Serial.print(".");
  }
  Serial.println("Connected to the Wi-Fi network");
  
  LCD.clear();
  LCD.setCursor(0, 0);
  LCD.println("Online");
  LCD.setCursor(0, 1);
  LCD.println("setup MQTT");
  setupMQTT(&wifiMqtt);
  LCD.clear();
  LCD.setCursor(0, 0);
  LCD.println("Online");
  LCD.setCursor(0, 1);
  LCD.println("setup MQTT run");
}

void loop() {
  if (isWifiConnected()) {// Ưu tiên đầu, nếu có wifi thì xử lý kết nối mqtt với wifi
    mqttLoopWithWifi();
  }
  // if (wifiMqtt.connected() && (millis()-t0)>1000)
  // {
  //   int gasValue = analogRead(GASpin);

  //   float temp = dht.readTemperature();
  //   float hum = dht.readHumidity();
  //   // if (isnan(temp)) temp = 0;
  //   // if (isnan(hum)) hum = 0;
  //   JSONVar sendJson;
  //   sendJson["type"] = "data";
  //   sendJson["Gas"] = gasValue;
  //   sendJson["Temp"] = temp;
  //   sendJson["Hum"] = hum;
  //   String jsonString = JSON.stringify(sendJson); //có 2 ms
  //   Serial.print("JSON.stringify(myObject) = ");
  //   Serial.println(jsonString);
  //   wifiMqtt.publish(topic_sensor, jsonString.c_str());
    
  //   if(foundOled) printDisplay(gasValue, temp, hum);
    
  //   if (gasValue >= 100) digitalWrite(LED, HIGH);
  //   else digitalWrite(LED, LOW);
  //   t0=millis();
  // }
}