#include <WiFi.h>
#include <PubSubClient.h>
#include <ESP32Servo.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <ArduinoJson.h>

// ===== WiFi Config =====
const char* ssid = "Wokwi-GUEST";    // ganti dengan WiFi Anda
const char* password = "";

// ===== ThingsBoard Config =====
const char* mqtt_server = "thingsboard.cloud";   // server ThingsBoard
const int mqtt_port = 1883;
const char* access_token = "yjisll1rfplofacx7a2e";  // token device dari ThingsBoard

WiFiClient espClient;
PubSubClient client(espClient);

// ===== Pin Config =====
const int potPin    = 34;  // Potentiometer pin (ADC)
const int servo1Pin = 18;
const int servo2Pin = 19;

Servo servo1;
Servo servo2;

// ===== OLED Config =====
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET    -1
#define SCREEN_ADDRESS 0x3C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// ===== Variabel kontrol =====
int virtualPotValue = -1;  // -1 = pakai potensiometer fisik

// ===== MQTT Callback =====
void callback(char* topic, byte* message, unsigned int length) {
  String msg;
  for (unsigned int i = 0; i < length; i++) {
    msg += (char)message[i];
  }
  Serial.printf("Message arrived [%s] %s\n", topic, msg.c_str());

  if (String(topic).startsWith("v1/devices/me/rpc/request/")) {
    DynamicJsonDocument doc(256);
    deserializeJson(doc, msg);
    String method = doc["method"];
    
    if (method == "setState") {
      int value = doc["params"];
      virtualPotValue = constrain(value, 0, 180);
      servo1.write(virtualPotValue);
      servo2.write(virtualPotValue);
      Serial.printf("Servo angle via setState: %d\n", virtualPotValue);
    }
    
    if (method == "getState") {
      String responseTopic = String("v1/devices/me/rpc/response/") + 
                             String(topic).substring(String(topic).lastIndexOf("/") + 1);
      String payload = String(virtualPotValue);
      client.publish(responseTopic.c_str(), payload.c_str());
      Serial.printf("Responding getState: %d\n", virtualPotValue);
    }
  }
}  // <<<=== KURUNG callback() HARUS DITUTUP DI SINI

// ===== MQTT Reconnect =====
void reconnect() {
  while (!client.connected()) {
    Serial.print("Connecting to ThingsBoard...");
    if (client.connect("ESP32Client", access_token, NULL)) {
      Serial.println("connected");
      // Subscribe RPC request ThingsBoard
      client.subscribe("v1/devices/me/rpc/request/+");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      delay(2000);
    }
  }
}

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

  // Servo init
  servo1.attach(servo1Pin);
  servo2.attach(servo2Pin);

  // OLED init
  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;); // Berhenti kalau gagal
  }
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("ESP32 Servo Monitor");
  display.display();

  // WiFi init
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected");

  // MQTT init
  client.setServer(mqtt_server, mqtt_port);
  client.setCallback(callback);

  // Servo ke posisi awal
  int initialServo = 90;
  servo1.write(initialServo);
  servo2.write(initialServo);

  // kirim nilai awal ke ThingsBoard
  String payload = String("{\"servo\":") + initialServo + "}";
  client.publish("v1/devices/me/telemetry", payload.c_str());
}

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

  // Tentukan angle berdasarkan RPC atau potensiometer fisik
  int angle;
  if (virtualPotValue >= 0) {
    angle = virtualPotValue;  // nilai dari ThingsBoard
  } else {
    int potValue = analogRead(potPin);  // nilai fisik
    angle = map(potValue, 0, 4095, 0, 180);
  }

  // Gerakkan servo
  servo1.write(angle);
  servo2.write(angle);

  // Tampilkan ke OLED
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("ESP32 Servo Monitor");
  display.drawLine(0, 10, SCREEN_WIDTH, 10, SSD1306_WHITE);
  display.setCursor(0, 20);
  display.println("Angle Servo:");
  display.setTextSize(2);
  display.setCursor(0, 35);
  display.printf("%d deg", angle);
  display.display();

  // Kirim telemetry ke ThingsBoard
  String payload = String("{\"angle\":") + angle + "}";
  client.publish("v1/devices/me/telemetry", payload.c_str());
  Serial.printf("Published angle: %d\n", angle);

  delay(2000);
}