/*
  Project: Lampu Tidur ESP32 dengan Sensor Tepuk (LDR), LCD I2C, dan Alarm Jam Internal (tanpa RTC)
  Deskripsi:
  - Sensor LDR dipakai sebagai pengganti sensor suara
  - Saat nilai LDR berubah cepat (simulasi tepuk), lampu akan toggle (nyala/mati)
  - Jam diambil dari waktu internal NTP (tanpa modul RTC)
  - Alarm diset via Serial, contoh: SET 05:00
  - Saat waktu sesuai, buzzer bunyi dan lampu mati otomatis
*/

#include <WiFi.h>
#include "time.h"
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// ====== Konfigurasi ======
const char* WIFI_SSID = "YOUR_WIFI_SSID";
const char* WIFI_PASS = "YOUR_WIFI_PASSWORD";
const char* ntpServer = "pool.ntp.org";
const long gmtOffset_sec = 7 * 3600;  // UTC+7 (WIB)
const int daylightOffset_sec = 0;

// ====== Pin Setup (sesuai gambar) ======
#define PIN_LDR 34      // AO dari sensor LDR
#define PIN_LAMP 2      // LED
#define PIN_BUZZER 15   // Buzzer
#define SDA_PIN 21
#define SCL_PIN 22

// ====== Konstanta ======
#define CLAP_DELTA_THRESHOLD 120
#define CLAP_DEBOUNCE_MS 400

// ====== Variabel ======
bool lampState = false;
int lastLdrValue = 0;
unsigned long lastClapTime = 0;
bool alarmEnabled = false;
bool alarmTriggeredToday = false;
int alarmHour = -1;
int alarmMinute = -1;

// ====== LCD I2C ======
LiquidCrystal_I2C lcd(0x27, 16, 2);

// ====== Buzzer ======
#define BUZZER_CHANNEL 0
#define BUZZER_FREQ 2000
#define BUZZER_RESOLUTION 8

void setup() {
  Serial.begin(115200);
  delay(1000);

  // Setup pin
  pinMode(PIN_LAMP, OUTPUT);
  digitalWrite(PIN_LAMP, LOW);
  pinMode(PIN_BUZZER, OUTPUT);

  // Setup buzzer PWM
  ledcSetup(BUZZER_CHANNEL, BUZZER_FREQ, BUZZER_RESOLUTION);
  ledcAttachPin(PIN_BUZZER, BUZZER_CHANNEL);
  ledcWrite(BUZZER_CHANNEL, 0);

  // Setup LCD
  Wire.begin(SDA_PIN, SCL_PIN);
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Connecting WiFi");

  // Setup WiFi dan waktu
  connectWiFi();
  configTime(gmtOffset_sec, daylightOffset_sec, ntpServer);
  delay(1000);
  lcd.clear();
  lcd.print("Ready...");

  lastLdrValue = analogRead(PIN_LDR);
  Serial.println("=== Sistem Siap ===");
  Serial.println("Perintah: SET hh:mm | OFF | STATUS");
}

void loop() {
  checkClap();
  displayTime();
  checkAlarm();
  handleSerial();
  delay(100);
}

// ====== Fungsi ======
void connectWiFi() {
  WiFi.begin(WIFI_SSID, WIFI_PASS);
  Serial.print("Connecting");
  int retry = 0;
  while (WiFi.status() != WL_CONNECTED && retry < 30) {
    delay(500);
    Serial.print(".");
    retry++;
  }
  Serial.println();

  if (WiFi.status() == WL_CONNECTED) {
    Serial.println("WiFi Connected!");
    lcd.clear();
    lcd.print("WiFi Connected");
  } else {
    Serial.println("WiFi Failed!");
    lcd.clear();
    lcd.print("WiFi Failed");
  }
}

void checkClap() {
  int ldrValue = analogRead(PIN_LDR);
  int delta = abs(ldrValue - lastLdrValue);

  if (delta > CLAP_DELTA_THRESHOLD && (millis() - lastClapTime > CLAP_DEBOUNCE_MS)) {
    lastClapTime = millis();
    lampState = !lampState;
    digitalWrite(PIN_LAMP, lampState ? HIGH : LOW);
    Serial.printf("Clap detected! Lamp %s\n", lampState ? "ON" : "OFF");
  }

  lastLdrValue = ldrValue;
}

void displayTime() {
  struct tm timeinfo;
  if (getLocalTime(&timeinfo)) {
    lcd.setCursor(0, 0);
    lcd.printf("%02d:%02d:%02d     ", timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec);

    lcd.setCursor(0, 1);
    if (alarmEnabled)
      lcd.printf("Alarm %02d:%02d ", alarmHour, alarmMinute);
    else
      lcd.print("Alarm OFF      ");
  } else {
    lcd.setCursor(0, 0);
    lcd.print("No Time Data   ");
  }
}

void checkAlarm() {
  if (!alarmEnabled) return;

  struct tm timeinfo;
  if (!getLocalTime(&timeinfo)) return;

  if (timeinfo.tm_hour == alarmHour && timeinfo.tm_min == alarmMinute && !alarmTriggeredToday) {
    alarmTriggeredToday = true;
    Serial.println("Alarm triggered!");
    lampState = false;
    digitalWrite(PIN_LAMP, LOW);
    soundAlarm();
  }

  if (timeinfo.tm_hour == 0 && timeinfo.tm_min == 0)
    alarmTriggeredToday = false;
}

void soundAlarm() {
  unsigned long start = millis();
  while (millis() - start < 10000) {
    ledcWrite(BUZZER_CHANNEL, 200);
    delay(300);
    ledcWrite(BUZZER_CHANNEL, 0);
    delay(300);
  }
  ledcWrite(BUZZER_CHANNEL, 0);
  Serial.println("Alarm stopped.");
}

void handleSerial() {
  if (!Serial.available()) return;
  String line = Serial.readStringUntil('\n');
  line.trim();
  line.toUpperCase();

  if (line.startsWith("SET ")) {
    int colon = line.indexOf(':');
    if (colon > 0) {
      alarmHour = line.substring(4, colon).toInt();
      alarmMinute = line.substring(colon + 1).toInt();
      alarmEnabled = true;
      alarmTriggeredToday = false;
      Serial.printf("Alarm set to %02d:%02d\n", alarmHour, alarmMinute);
    } else {
      Serial.println("Format salah! Gunakan: SET hh:mm");
    }
  } else if (line == "OFF") {
    alarmEnabled = false;
    Serial.println("Alarm dimatikan.");
  } else if (line == "STATUS") {
    Serial.printf("Lamp: %s | Alarm: %s %02d:%02d\n",
      lampState ? "ON" : "OFF",
      alarmEnabled ? "ON" : "OFF",
      alarmHour, alarmMinute);
  } else {
    Serial.println("Perintah tidak dikenal. Gunakan: SET hh:mm | OFF | STATUS");
  }
}