#define LED_PIN 12    //which pin I use
#define PWM1_Ch    0  //first channel of 16
#define PWM1_Res   8
#define PWM1_Freq  1000
 
int PWM1_DutyCycle = 0;

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

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

// MQTT broker details
const char* mqttServer = "broker.hivemq.com";
const int mqttPort = 1883;

// MQTT client details
const char* clientId = "actuator_2";   //the MQTT client identifier
const char* mqttTopic = "/polimi/iot/22-23/Genovese-Francesco/humidity1";//the MQTT topic

// Wi-Fi client and MQTT client
WiFiClient wifiClient;
PubSubClient client(wifiClient);  
// Wait for wifi to be connected
int notConnectedCounter = 0;

//
int uS_TO_mS_FACTOR=1000;  /* Conversion factor for micro seconds to milli seconds */
int InactivePart;          /* Time ESP32 will go to sleep (in milli seconds) */

bool isConnected = false;  //if the client is connected to the broker
bool isRegistered =false;  //if the client is connected to the PanC

//info from the PanC
int BI, CAP, CFP, ts, myIndex;
int Humidity;
unsigned long startTime;



void setup() {
  
  Serial.begin(115200);
  delay(500);
  // setup Wi-Fi
  
  WiFi.mode(WIFI_STA);  //setting the wifi in station mode
  WiFi.begin(ssid, password); //speciyng the SSID and password for the wifi
  
  
  Serial.print("Connecting to WiFi...");
  while (WiFi.status() != WL_CONNECTED) {
    Serial.print(".");
    delay(200);        //we keep waiting 0.2 seconds more for a connection until we get it
    
    notConnectedCounter++;
    if(notConnectedCounter > 20) { // Reset board if not connected after 20 tries
        Serial.println("Resetting due to Wifi not connecting...");
        ESP.restart();
    }         //problems here (sopra, nel wifi)
  }
  Serial.println("Connected to WiFi");

 
  // Connect to MQTT broker and set callback
  client.setServer(mqttServer, mqttPort);
  client.setCallback(callback);

  //first connection to the MQTT broker
  while (!client.connected()) {
    if (client.connect(clientId)) {
      Serial.println("Connected to MQTT broker");
      client.subscribe(mqttTopic);
      isConnected=true;
    } else {
      Serial.print("Failed to connect to MQTT broker. Client state=");
      Serial.println(client.state());
      Serial.println(" Retrying in 2 seconds...");
      delay(2000);
    }
  }





  //Set led pin as output
  pinMode(LED_PIN, OUTPUT);

  // configure LED PWM functionalitites
  ledcSetup(PWM1_Ch, PWM1_Freq, PWM1_Res);

 // attach the channel to the Pin to be controlled
  ledcAttachPin(LED_PIN, PWM1_Ch);
    
}



//maintaininig the MQTT connection while waiting for the beacon
 void loop() {
  //reconnect if not connected to the MQTT broker
  if (!client.connected()) {
    isConnected=false;
    reconnect();
  }
  client.loop();
}


void Turn_On(){

    byte led_dim = map(Humidity, 0, 100, 0, 255);
    ledcWrite(PWM1_Ch, led_dim);  
    delay(ts);
    ledcWrite(PWM1_Ch, 0); // Set brightness to 0 (LED off)
    Serial.println("LED turned off");
    Humidity=0;
}



//reconnecting to the broker when a disconnection happen
void reconnect() {
  while (!client.connected()) {
    Serial.println("Attempting MQTT connection...");
    if (client.connect(clientId)) {
      Serial.println("Connected to MQTT broker");
      client.subscribe(mqttTopic);
      isConnected=true;
    } else {
      Serial.print("Failed to connect to MQTT broker, rc=");
      Serial.print(client.state());
      Serial.println(" Retrying in 0.5 seconds...");
      delay(500);
    }
  }
}

// Handle incoming MQTT messages
void callback(char* topic, byte* payload, unsigned int length) {
//syncro= millis();  //to syncronize the clients
  
  /*     delete this to check the message
  // Print the Topic
  Serial.print("Topic: "); Serial.println(topic);
  
  // Print the Message
  Serial.print("Message: ");
  */  
  String s="";
  for (unsigned int i = 0; i < length; i++) {
    s += (char)payload[i];
  }
  Serial.println("");
 
  if(s.indexOf("BI")==1){
  startTime=millis();
  Serial.println("New MQTT message received:");
  Serial.println(s);
    //reading BI
    int firstReadBI =s.indexOf("BI")+3;
    int stopReadBI =s.indexOf("/");
    String BIs= s.substring(firstReadBI,stopReadBI);
    BI= BIs.toInt();
    Serial.print("BI: "); Serial.println(BI);

    //reading CAP
    int firstReadCAP =s.indexOf("CAP")+4;
    int stopReadCAP =s.indexOf("CFP")-1;
    String CAPs= s.substring(firstReadCAP,stopReadCAP);
    CAP= CAPs.toInt();
    Serial.print("CAP: "); Serial.println(CAP);

    //reading CFP
    int firstReadCFP =s.indexOf("CFP")+4;
    int stopReadCFP =s.indexOf("ts")-1;
    String CFPs= s.substring(firstReadCFP,stopReadCFP);
    CFP= CFPs.toInt();
    Serial.print("CFP: "); Serial.println(CFP);

    //reading ts
    int firstReadts =s.indexOf("ts")+3;
    int stopReadts =s.indexOf("slot")-1;
    String tss= s.substring(firstReadts,stopReadts);
    ts= tss.toInt();
    Serial.print("ts: "); Serial.println(ts);

    //reading myIndex
    int lenghtId =strlen(clientId);
    int firstReadmyIndex =s.indexOf(clientId)+lenghtId+1;
    int stopReadmyIndex =s.indexOf("}");
    String myIndexs= s.substring(firstReadmyIndex,stopReadmyIndex);
    myIndex= myIndexs.toInt();
    if(!myIndex){
      Serial.println("Al momento non siamo iscritti");
      isRegistered=false;
    }else{
      isRegistered=true;
    Serial.print("myIndex: "); Serial.println(myIndex);     //check if my index is right
    }
  }else{
    // reading the humidity, if the message comes from a sensor
    int lenghtHumidity =strlen(clientId);
    int firstReadmyHumidity =s.indexOf(clientId)+lenghtHumidity+1;
    //int stopReadmyhumidity =s.indexOf("}");
    String myHumiditys= s.substring(firstReadmyHumidity);
    Humidity= myHumiditys.toInt();
    if(Humidity){
      Serial.print("my humidity is: "); Serial.println(Humidity);
    }
  }


  InactivePart=(BI-ts-CAP-CFP-250);
  esp_sleep_enable_timer_wakeup(InactivePart * uS_TO_mS_FACTOR);
  timerCallback();
}


// Manage the active part
void timerCallback() {  
     
  //delay for the beacon slot
  do{
    delay(1); 
  }while((millis()-startTime)<ts);

  //registration during the CAP
  unsigned int a;  
  if(!isRegistered){
    
    a=random(CAP); 
    Serial.print("a="); Serial.println(a);   
    do{
      delay(1); 
    }while((millis()-startTime)<(ts+a));     //i delay for a random value during the cap, to register this client
    registration();   
  } 

  if((myIndex!=0)&&(Humidity)){
   
    do{
      delay(1); 
    }while((millis()-startTime)<(CAP+ts*myIndex));      //here we get to our indicated slot (-1 because i wrote in the beacon all index +1, because an index =0 for this code means no index)
    Turn_On();
  }

  /*
  //now we go to the deep sleep state
  Serial.println("Setup ESP32 to sleep for  " + String(InactivePart) + " milli-seconds");
  
  // Disconnect from Wi-Fi before entering deep sleep
  WiFi.disconnect(true);

  esp_deep_sleep_start();
  */
}
// problemi qua sopra


// here is where the clients ask the registration to the PanC
void registration ()
{
  client.publish(mqttTopic,clientId);
  Serial.print("my name is: "); Serial.println(clientId);
  isRegistered=true;
}