#include <WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>
#include <ESP32Servo.h>
#include <uRTCLib.h>

const int servoPin = 18;
#define Ldrpin 35
int LED_R = 23;

Servo myServo; // Creates a servo object for controlling the servo motor
int angle = 0;

const char *WIFI_SSID = "Wokwi-GUEST";
const char *WIFI_PWD = "";

const char *MQTT_SERVER = "broker.hivemq.com";  // MQTT server name
const uint16_t MQTT_PORT = 1883; // MQTT port number to use

WiFiClient wifiClient;
PubSubClient mqttClient(wifiClient);
// ---------------------------


// ---------------------------
const char *topicPubSensor = "IOT/PA31/s10206236";
const char *topicPubDist = "IOT/PA31/dist";
const char *topicPubTemp = "IOT/PA31/temp";
const char *topicPubHumi = "IOT/PA31/humi";
const char *topicPubDate = "IOT/PA31/date";
const char *topicPubLux = "IOT/PA31/lux";

// defines variables
char daysOfTheWeek[7][12] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
uRTCLib rtc(0x68);
long duration;
int distance;
//**************
void SetupRtc()
{
  URTCLIB_WIRE.begin();
}
void ConnectToWiFi()
{
  Serial.print("Connecting to WiFi ");
  Serial.println(WIFI_SSID);

  WiFi.begin(WIFI_SSID, WIFI_PWD, 6);
  while (WiFi.status() != WL_CONNECTED)
  {
    Serial.print(".");
    delay(500);
  }
  Serial.print("\nConnected to ");
  Serial.println(WIFI_SSID);
}
//--------------------------------------------------------
void SetupMqtt()
{
  mqttClient.setServer(MQTT_SERVER, MQTT_PORT);
  // set the callback function
  mqttClient.setCallback(callback);
}

void ConnectToMqtt()
{
  Serial.println("Connecting to MQTT Broker...");
  while (!mqttClient.connected())
  {
    char clientId[100] = "\0";
    sprintf(clientId, "ESP32Client-%04X", random(0xffff));
    Serial.println(clientId);

    if (mqttClient.connect(clientId))
    {
      Serial.println("Connected to MQTT broker.");
      // subscribe to topics
      MQTTSubscribe();
    }
  }
}

void callback(String topic, byte* payload, unsigned int length)
{
  String messageTemp;
  Serial.print("\nMessage received in topic: ");
  Serial.print(topic);
  Serial.print(" length is: ");
  Serial.println(length);

  Serial.print("Data received from broker: ");
  for (int i = 0; i < length; i++)
  {
    Serial.print( (char)payload[i] );
    messageTemp += (char)payload[i];
  }
//The whole code above is just to print all the message recieved (payload)

  int value = messageTemp.toInt();
  if ( topic == topicPubDate)
  {
    if (messageTemp == "00:00")
    {
      for(angle = 0; angle <= 180; angle+=180)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(10000);
      }

      // rotates the servo motor from 180 to 0 degrees
      for(angle = 180; angle >= 0; angle-=180)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(10000);
      }
    }
    else if (messageTemp == "08:00")
    {
      for(angle = 0; angle <= 180; angle+=180)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(10000);
      }

      // rotates the servo motor from 180 to 0 degrees
      for(angle = 180; angle >= 0; angle-=180)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(10000);
      }
    }
    else if (messageTemp == "16:00")
    {
      for(angle = 0; angle <= 180; angle+=180)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(10000);
      }

      // rotates the servo motor from 180 to 0 degrees
      for(angle = 180; angle >= 0; angle-=180)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(10000);
      }
    }
  }
  else if (topic == topicPubTemp) {
    if (value > 30) {
      // rotates the servo motor from 0 to 180 degrees
      for(angle = 0; angle <= 180; angle+=15)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(100);
      }

      // rotates the servo motor from 180 to 0 degrees
      for(angle = 180; angle >= 0; angle-=15)
      {
        myServo.write(angle); // tells servo to go to position in variable 'angle'
        delay(100);
      }
    }
  }
  else if (topic == topicPubLux) {
    if (value < 50) {
      digitalWrite(LED_R, LOW);
    }
    else {
      digitalWrite(LED_R, HIGH);
    }
  }
  else {
    Serial.printf("\nReceived topic \"%s\" + payload \"%s\" not processed",
                  topic.c_str(), messageTemp.c_str());
  }
}

void MQTTSubscribe() 
{
  Serial.printf("\n--- Subscribe to topics:");
  Serial.printf("\n%s", topicPubSensor);
  mqttClient.subscribe(topicPubSensor);

  Serial.printf("\n%s", topicPubDist);
  mqttClient.subscribe(topicPubDist);

  Serial.printf("\n%s", topicPubTemp);
  mqttClient.subscribe(topicPubTemp);
  
  Serial.printf("\n%s", topicPubHumi);
  mqttClient.subscribe(topicPubHumi);

  Serial.printf("\n%s", topicPubDate);
  mqttClient.subscribe(topicPubDate);

  Serial.printf("\n%s", topicPubLux);
  mqttClient.subscribe(topicPubLux);
}

//--------------------------------------------------------
// Publish a topic with its payload
bool publishTopic(const char* topic, const char *str) {
  Serial.printf("\nPublishing topic \"%s\" + payload \"%s\"", topic, str);
  if (mqttClient.publish(topic, str)) {
    Serial.print(" -- Done");
    return true;
  }
  else {
    Serial.print("\nPublishing encounter error");
    return false;
  }
}
//--------------------------------------------------------

// ---------------------------
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(LED_R,OUTPUT);
  myServo.attach(18); // Defines the attached pin of servo motor 
  SetupRtc();
  ConnectToWiFi();
  SetupMqtt();
  ConnectToMqtt(); // This line establishes the MQTT connection
}
const size_t BUFFER_SIZE = 100;
const char *BUFFER_FORMAT = "%1.3f";
char buffer[BUFFER_SIZE + 1]; 
const float GAMMA = 0.7; 
const float RL10 = 50;

void loop() {
  // put your main code here, to run repeatedly:
  delay(10); // this speeds up the simulation
  if (!mqttClient.connected())
  {
    ConnectToMqtt();
  }
  mqttClient.loop();
  {
    rtc.refresh();
    snprintf(buffer, BUFFER_SIZE, "%02d:%02d",rtc.hour(), rtc.minute());
    mqttClient.publish("IOT/PA31/date", buffer);
    Serial.print("\nCurrent Hour in 24 hour format: ");
    Serial.println(buffer);

    int ldrValue = analogRead(Ldrpin);
    float voltage = ldrValue / 4095. * 5;
    float resistance = 2000.0 * voltage / (1 - voltage / 5);
    float lux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1.0 / GAMMA));
    char luxStr[20];
    dtostrf(lux, 6, 3, luxStr); // Format: %6.3f (6 characters wide, 3 decimal places)
    Serial.println(luxStr); // Print the lux value to Serial Monitor
    mqttClient.publish("IOT/PA31/lux", luxStr); // Publish the lux value
  } //make sure connection is not broken, auto restart the connection
  delay(1000);
}