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

#define ON 1
#define OFF 0

Servo myServo;
WiFiClient espClient;

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqttServer = "mqtt.netpie.io";
const int mqttPort = 1883;
const char* clientID = "c61fb73f-6caf-4bf0-87fe-2f87acd0104b";
const char* mqttUser = "4aigSaeuurMZaaV4Y7LyAcN8oriJiDVy";
const char* mqttPassword = "QZ1C9hMyy3TUNunCN2L5eKkoej3jXd1B";
const char* topic_pub = "@shadow/data/update";
const char* topic_sub = "@msg/lab_ict_kps/command";

String publishMessage;

PubSubClient client(espClient);

const int TRIGGER_PIN = 16;
const int ECHO_PIN = 17;
const int SERVO_PIN = 4;
const int button = 12;
int servo_status = OFF;
int current_mode = 0;
const int mode_1 = 32;
const int mode_2 = 33;


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

void reconnectMQTT() {
  while (!client.connected()) {
    Serial.println("Attempting MQTT connection...");
    String clientId = clientID;
    if (client.connect(clientId.c_str(), mqttUser, mqttPassword)) {
      Serial.println("Connected to MQTT");
      client.subscribe(topic_sub);
    } else {
      Serial.print("Failed, rc=");
      Serial.print(client.state());
      Serial.println(" Retrying in 5 seconds...");
      delay(5000);
    }
  }
}

void messageReceivedCallback(char* topic, byte* payload, unsigned int length) { 
  char payloadMsg[80];
  Serial.print("Message arrived in topic: ");
  Serial.println(topic); 
  Serial.print("Message:");
  for (int i = 0; i < length; i++) {
    Serial.print((char)payload[i]);
    payloadMsg[i] = (char) payload[i];
  }
  payloadMsg[length] = '\0';
  Serial.println();
  Serial.println("-----------------------");
  processMessage(payloadMsg);

}

void processMessage(String recvCommand) {
  if (recvCommand == "SERVO_OPEN") {
    myServo.write(180); 
    servo_status = ON;// Set Servo to 0 degrees (open position)
  } else if (recvCommand == "SERVO_CLOSE") {
    myServo.write(0);
    servo_status = OFF; // Set Servo to 180 degrees (closed position)
  }
  // You can add more conditions for controlling the Servo based on other commands
}

void setup() {
  Serial.begin(115200);
  setup_wifi();
  client.setServer(mqttServer, mqttPort);
  client.setCallback(messageReceivedCallback); 
  pinMode(TRIGGER_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  myServo.attach(4);
  servo_status = OFF;
  pinMode(button, INPUT_PULLUP);
  pinMode(mode_1, OUTPUT);
  pinMode(mode_2, OUTPUT);
}

void loop() {
  if (!client.connected()) {
    reconnectMQTT();
  }
  client.loop();

  long duration, distance;
  digitalWrite(TRIGGER_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIGGER_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGGER_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2;
  if(digitalRead(button) == 0){
    current_mode = current_mode +1;
    if (current_mode > 1){
      current_mode = 0;
    }
    delay(100);
  }
  if (current_mode == 0)
{
  int angle = map(distance, 2, 400, 0, 180);
  myServo.write(angle);
  digitalWrite(mode_1, HIGH);
  digitalWrite(mode_2, LOW);
}
else if (current_mode == 1)
{
  digitalWrite(mode_1, LOW);
  digitalWrite(mode_2, HIGH);
}

  String distanceStr = String(distance);
  publishMessage = "{\"data\": {\"distance\": " + distanceStr + ",\"servo\":" + String(servo_status)+ "}}";
  client.publish(topic_pub, publishMessage.c_str());
  Serial.println(publishMessage);

  delay(100);
}