#include <WiFi.h>
#include <PubSubClient.h>
#include <ArduinoJson.h>
#define TOKEN "hhZqt27zIGhbfpyD35XQ"
const int LDR_PIN = 33; // LDR (Photoresistor) connected to Analog Pin A0
const int SWITCH_PIN = 14;
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "demo.thingsboard.io";
WiFiClient espClient;
PubSubClient client(espClient);
unsigned long lastRead = 0;
unsigned long lastMsg = 0;
unsigned long lastThreshold = 0;
#define MSG_BUFFER_SIZE (50)
int lightLevel = 0;
int switch_state;
int threshold = 0;
void setup_wifi() {
  delay(10);
  // We start by connecting to a WiFi network
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);

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

  randomSeed(micros());

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

void callback(const char* topic, byte* payload, unsigned int length){
 char json[length + 1];
 strncpy (json, (char*)payload, length);
 json[length] = '\0';
 
 Serial.println("Topic: ");
 Serial.println(topic);
 
 Serial.println("Message: ");
 
 Serial.println(json);
 
 StaticJsonDocument<200> jsonBuffer;
 
  DeserializationError data = deserializeJson(jsonBuffer, json);
 
 if (data){
 Serial.println("parseObject() failed");
 return;
 }
  threshold = jsonBuffer["params"]["Threshold"];
  Serial.print("Nguong:"); Serial.println(threshold);
}


void reconnect(){
 while (!client.connected()){
 if(WiFi.status() != WL_CONNECTED){
 WiFi.begin(ssid, password);
 while(WiFi.status() != WL_CONNECTED){
 delay(500);
 Serial.print(".");
 }
 Serial.println("Connected to AP");
 }
 Serial.print("Connecting to ThingsBoard node ...");
 if ( client.connect ("SensorIoT", TOKEN, NULL)){
 Serial.println( "[DONE]" );
 client.subscribe("v1/devices/me/rpc/request/+");
 }
 else {
 Serial.print("[FAILED] [ rc = " );
 Serial.print(client.state() );
 Serial.println( " : retrying in 5 seconds]");
 delay( 5000 );
 }
 }
}

void setup() {
  Serial.begin(115200);
  setup_wifi();
  pinMode(SWITCH_PIN, INPUT);
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  unsigned long now = millis();
  if (now - lastRead > 500) {
    // Read the LDR value
    lightLevel = analogRead(LDR_PIN);
    int percent = map(lightLevel, 0, 1023, 0, 100);
    Serial.print("Light Level: ");
    Serial.print(percent);
    Serial.println(" %");
    lastRead = now;
  }
  if(now - lastMsg > 5000){
    SendData();
    lastMsg = now;
  }
  if(now - lastThreshold > 6000){
    Serial.println("Check ThreshHold");
    ThresholdUpdate();
    lastThreshold = now;
  }
  client.loop();
}
void SendData(){
  lightLevel = analogRead(LDR_PIN);
  int percent = map(lightLevel, 0, 1023, 0, 100);
  String Light_level = String(percent);
  String State;
  switch_state = digitalRead(SWITCH_PIN);
  if(switch_state == 1){
    State = "On";
  }else{
    State = "Off";
  }
  String payload = "{";
 payload += "\"light_level\":"; payload += Light_level; payload += ",";
 payload += "\"switch_status\":"; payload += State;
 payload += "}";
 char telemetry[100];
 payload.toCharArray( telemetry, 100 );
 client.publish( "v1/devices/me/telemetry", telemetry );
 Serial.println("Send Data Successful");
}
void ThresholdUpdate(){
  Serial.print("Threshold Value: ");
  Serial.println(threshold);
}