[Part 17] Control the air conditioner from the IoT hub - IR transmitter node

#include <ESP8266WiFi.h>
#include <ESP8266HTTPClient.h>
#include <IRremoteESP8266.h>
#include <IRsend.h>
#include <IRrecv.h>
#include <IRutils.h>

const char* ssid     = "IoT_Hub_Net";
const char* password = "iothub1234";
const char* hubURL   = "http://192.168.1.1";

#define IR_RECV  5    // D1 (GPIO5) - VS1838B receive
#define IR_SEND  4    // D2 (GPIO4) - IR LED send
#define SLOT_NO  4    // brain 4note= AC

// =============================================
// note!
// =============================================
// note
// note
unsigned long long AC_ON_CODE  = 0x0; // ← note
unsigned long long AC_OFF_CODE = 0x0; // ← note

IRrecv irrecv(IR_RECV);
IRsend irsend(IR_SEND);
decode_results results;

String lastState = "--";
bool codesLearned = false;

// =============================================
// setup
// =============================================
void setup() {
  Serial.begin(115200);
  irsend.begin();
  irrecv.enableIRIn();

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  Serial.print("Connecting to IoT_Hub_Net");
  while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); }
  Serial.println("\nConnected! IP: " + WiFi.localIP().toString());

  // note
  if (AC_ON_CODE != 0x0 && AC_OFF_CODE != 0x0) {
    codesLearned = true;
    irrecv.disableIRIn();
    Serial.println("=== CODES ALREADY SET, SKIPPING LEARNING ===");
    Serial.print("AC_ON_CODE:  0x"); Serial.println((unsigned long)AC_ON_CODE, HEX);
    Serial.print("AC_OFF_CODE: 0x"); Serial.println((unsigned long)AC_OFF_CODE, HEX);
    Serial.println("Ready. Waiting for /set?no4=ON or OFF...");
    return;
  }

  // ── IR note──
  Serial.println();
  Serial.println("==========================================");
  Serial.println("  IR LEARNING MODE");
  Serial.println("==========================================");
  Serial.println("1. Point AC remote at VS1838B sensor.");
  Serial.println("2. Press ON button on the remote.");
  Serial.println("3. Press OFF button on the remote.");
  Serial.println("4. Copy the codes to AC_ON_CODE / AC_OFF_CODE");
  Serial.println("   in this sketch and re-upload.");
  Serial.println("==========================================");
  Serial.println();

  bool gotOn = false;
  bool gotOff = false;
  unsigned long startTime = millis();

  // note
  while (!gotOn || !gotOff) {
    if (millis() - startTime > 30000) {
      Serial.println("TIMEOUT: Learning mode ended.");
      break;
    }

    if (irrecv.decode(&results)) {
      unsigned long long code = results.value;
      uint16_t protocol = results.decode_type;

      if (!gotOn) {
        AC_ON_CODE = code;
        gotOn = true;
        Serial.print("AC_ON_CODE:  0x");
        Serial.println((unsigned long)code, HEX);
        Serial.println("  Now press OFF button...");
      } else if (!gotOff) {
        // OFF note
        if (code == AC_ON_CODE) {
          Serial.println("  WARNING: OFF code same as ON code!");
          Serial.println("  Your remote is toggle-type. Use the captured code for both.");
        }
        AC_OFF_CODE = code;
        gotOff = true;
        Serial.print("AC_OFF_CODE: 0x");
        Serial.println((unsigned long)code, HEX);
      }

      irrecv.resume();
    }
    delay(100);
  }

  irrecv.disableIRIn();
  codesLearned = (gotOn && gotOff);

  if (codesLearned) {
    Serial.println();
    Serial.println("=== LEARNING COMPLETE ===");
    Serial.println("Copy these two lines into the sketch and re-upload:");
    Serial.println();
    Serial.print("unsigned long long AC_ON_CODE  = 0x");
    Serial.println((unsigned long)AC_ON_CODE, HEX);
    Serial.print("unsigned long long AC_OFF_CODE = 0x");
    Serial.println((unsigned long)AC_OFF_CODE, HEX);
  } else {
    Serial.println("=== LEARNING FAILED ===");
    Serial.println("Restart the device and try again.");
  }
}

// =============================================
// loop
// =============================================
void loop() {
  if (!codesLearned) {
    Serial.println("Waiting for IR codes to be learned...");
    delay(5000);
    return;
  }

  // ── brainnote──
  WiFiClient client;
  HTTPClient http;
  String url = String(hubURL) + "/status";
  http.begin(client, url);
  int code = http.GET();

  if (code == 200) {
    String resp = http.getString();

    // no4 value note
    int pos = resp.indexOf("\"no4\":\"");
    if (pos > 0) {
      int start = pos + 7;
      int end = resp.indexOf("\"", start);
      String val = resp.substring(start, end);

      // statussend IR only when the value changes
      if (val != lastState) {
        Serial.print("State changed: ");
        Serial.print(lastState);
        Serial.print(" -> ");
        Serial.println(val);

        if (val == "ON") {
          Serial.print("Sending IR: AC ON  (0x");
          Serial.print((unsigned long)AC_ON_CODE, HEX);
          Serial.println(")");
          irsend.sendNEC(AC_ON_CODE, 32);
          delay(100);
        } else if (val == "OFF") {
          Serial.print("Sending IR: AC OFF (0x");
          Serial.print((unsigned long)AC_OFF_CODE, HEX);
          Serial.println(")");
          irsend.sendNEC(AC_OFF_CODE, 32);
          delay(100);
        }

        // IR note
        lastState = val;

        // note
        WiFiClient c2;
        HTTPClient h2;
        String fbUrl = String(hubURL) + "/set?no4=" + val;
        h2.begin(c2, fbUrl);
        h2.GET();
        h2.end();
        Serial.println("Feedback -> " + fbUrl);
      }
    }
  } else {
    Serial.print("HTTP ");
    Serial.print(code);
    Serial.println(" - retrying...");
  }

  http.end();
  delay(3000);
}

AC_ON_CODE:  0x880804F
AC_OFF_CODE: 0x880846B

unsigned long long AC_ON_CODE  = 0x880804F;  // copied value
unsigned long long AC_OFF_CODE = 0x880846B;  // copied value