#include <WiFi.h>
#include <WebServer.h>
#include <HTTPClient.h>
#include <Keypad.h>

const char* ssid = "Wokwi-GUEST";
const char* password = "";

String writeAPIKey = "JQ53BYN69KKIOLJS";
String serverTS = "https://api.thingspeak.com/update?api_key=";

const int buzzerPin = 19;

#define NOTE_C   261
#define NOTE_D   294
#define NOTE_E   329
#define NOTE_F   349
#define NOTE_G   392
#define NOTE_A   440
#define NOTE_B   494
#define NOTE_C2  523

const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};
byte rowPins[ROWS] = {18, 5, 17, 16};
byte colPins[COLS] = {4, 0, 2, 15};  

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// ===== Countdown Variabel =====
unsigned long lastUpdate = 0;
const unsigned long updateInterval = 15000; // 15 detik
bool countdownAktif = false;
unsigned long countdownStart = 0;

void updateThingSpeak(int field, int value) {
  unsigned long now = millis();
  if (now - lastUpdate >= updateInterval) {
    if (WiFi.status() == WL_CONNECTED) {
      HTTPClient http;
      String url = serverTS + writeAPIKey + "&field" + String(field) + "=" + String(value);
      http.begin(url);
      int httpCode = http.GET();
      if (httpCode > 0) {
        Serial.println("ThingSpeak updated: field" + String(field) + " = " + String(value));
      } else {
        Serial.println("Error updating ThingSpeak");
      }
      http.end();

      lastUpdate = now;

      // Mulai countdown
      countdownAktif = true;
      countdownStart = millis();
    }
  } else {
    Serial.println("Update diblokir, tunggu cooldown selesai.");
  }
}

void playNote(int freq, int duration, int field, int valueTS) {
  tone(buzzerPin, freq, duration);
  updateThingSpeak(field, valueTS); 
  Serial.print("Play note: ");
  Serial.println(valueTS);
  delay(duration + 100);
  noTone(buzzerPin);
}

void playNoteByName(String note) {
  if (note == "C") playNote(NOTE_C, 400, 1, 1);
  else if (note == "D") playNote(NOTE_D, 400, 1, 2);
  else if (note == "E") playNote(NOTE_E, 400, 1, 3);
  else if (note == "F") playNote(NOTE_F, 400, 1, 4);
  else if (note == "G") playNote(NOTE_G, 400, 1, 5);
  else if (note == "A") playNote(NOTE_A, 400, 1, 6);
  else if (note == "B") playNote(NOTE_B, 400, 1, 7);
  else if (note == "C2") playNote(NOTE_C2, 400, 1, 8);
}

void setup() {
  Serial.begin(115200);
  pinMode(buzzerPin, OUTPUT);

  WiFi.begin(ssid, password);
  Serial.print("Connecting to WiFi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println(" Connected!");
  Serial.print("IP ESP32: ");
  Serial.println(WiFi.localIP());
}

void loop() {
  char key = keypad.getKey();
  if (key) {
    Serial.print("Tombol ditekan: ");
    Serial.println(key);

    if (key == '1') playNoteByName("C");
    else if (key == '2') playNoteByName("D");
    else if (key == '3') playNoteByName("E");
    else if (key == '4') playNoteByName("F");
    else if (key == '5') playNoteByName("G");
    else if (key == '6') playNoteByName("A");
    else if (key == '7') playNoteByName("B");
    else if (key == '8') playNoteByName("C2");
  }

  // ===== Countdown Display =====
  if (countdownAktif) {
    unsigned long elapsed = millis() - countdownStart;
    int detikSisa = updateInterval / 1000 - elapsed / 1000;

    if (detikSisa >= 0) {
      static int lastShown = -1;
      if (detikSisa != lastShown) {  // hanya print sekali per detik
        Serial.println("Cooldown: " + String(detikSisa) + " detik");
        lastShown = detikSisa;
      }
    } else {
      countdownAktif = false; // selesai cooldown
      Serial.println("Siap update lagi!");
    }
  }
}