#include <Arduino.h>
#include "esp_sleep.h"

/* ================= MODE ================= */
// 1 = simulasi Wokwi
// 0 = hardware ESP32-C3 asli
#define SIM_WOKWI 1

#if !SIM_WOKWI
  #include <BLEDevice.h>
  #include <BLEServer.h>
  #include <BLEUtils.h>
  #include <BLE2902.h>
#endif

/* ================= PIN ================= */
#define PIN_BUTTON   5    // D3
#define PIN_ADC      2    // A0

#define LED_R        20   // D7
#define LED_G        21   // D6
#define LED_Y        7    // D5
#define LED_W        6    // D4
#define LED_B        8    // D8

/* ================= STATE ================= */
enum State {
  IDLE,
  WARMUP,
  RUN,
  OFF
};

State state = IDLE;

/* ================= TIMER ================= */
const unsigned long WARMUP_TIME  = 10000;
const unsigned long RUN_TIME     = 80000;
const unsigned long BLE_INTERVAL = 1000;

unsigned long startTime = 0;
unsigned long lastBle   = 0;

/* ================= BLE ================= */
#if !SIM_WOKWI
BLECharacteristic* txChar;
bool bleConnected = false;

class ServerCallbacks : public BLEServerCallbacks {
  void onConnect(BLEServer*) override {
    bleConnected = true;
    Serial.println("BLE connected");
  }

  void onDisconnect(BLEServer* server) override {
    bleConnected = false;
    Serial.println("BLE disconnected");
    server->startAdvertising();
  }
};
#endif

/* ================= HELPER ================= */
void setColor(bool r, bool g, bool y) {
  digitalWrite(LED_R, r);
  digitalWrite(LED_G, g);
  digitalWrite(LED_Y, y);
}

/* ================= BLE SEND ================= */
void sendBLE(const String& msg) {
#if SIM_WOKWI
  Serial.println("[BLE SIM] " + msg);
#else
  if (bleConnected) {
    txChar->setValue(msg.c_str());
    txChar->notify();
  }
#endif
}

/* ================= BLE FILE SEND ================= */
void sendFileBLE(const uint8_t* data, size_t length) {
  const size_t CHUNK_SIZE = 180;
  size_t offset = 0;

#if SIM_WOKWI
  Serial.println("[BLE SIM] SEND FILE START");
  Serial.print("SIZE: ");
  Serial.println(length);
  Serial.println("[BLE SIM] SEND FILE END");
#else
  if (!bleConnected) return;

  while (offset < length) {
    size_t chunkLen = min(CHUNK_SIZE, length - offset);
    txChar->setValue((uint8_t*)(data + offset), chunkLen);
    txChar->notify();
    offset += chunkLen;
    delay(20);
  }
#endif
}

/* ================= BLE SETUP ================= */
#if !SIM_WOKWI
void setupBLE() {
  BLEDevice::init("XIAO-GAS");

  BLEServer* server = BLEDevice::createServer();
  server->setCallbacks(new ServerCallbacks());

  BLEService* service = server->createService(
    "12345678-1234-1234-1234-1234567890ab"
  );

  txChar = service->createCharacteristic(
    "abcd1234-1a2b-3c4d-5e6f-abcdefabcdef",
    BLECharacteristic::PROPERTY_NOTIFY
  );

  txChar->addDescriptor(new BLE2902());
  service->start();
  server->getAdvertising()->start();

  Serial.println("BLE READY");
}
#endif

/* ================= SETUP ================= */
void setup() {
  Serial.begin(115200);

  pinMode(PIN_BUTTON, INPUT_PULLUP);
  pinMode(LED_R, OUTPUT);
  pinMode(LED_G, OUTPUT);
  pinMode(LED_Y, OUTPUT);
  pinMode(LED_W, OUTPUT);
  pinMode(LED_B, OUTPUT);

  analogReadResolution(12);

#if SIM_WOKWI
  Serial.println("MODE SIMULASI WOKWI");
#else
  setupBLE();
#endif

  Serial.println("SYSTEM SIAP");
}

/* ================= LOOP ================= */
void loop() {
  unsigned long now = millis();

  switch (state) {

    case IDLE:
      setColor(0,0,0);
      digitalWrite(LED_W, LOW);
      digitalWrite(LED_B, LOW);

      if (digitalRead(PIN_BUTTON) == LOW) {
        delay(300);
        state = WARMUP;
        startTime = now;
        Serial.println("MEMANASKAN SENSOR...");
      }
      break;

    case WARMUP:
      digitalWrite(LED_W, (now / 500) % 2);
      if (now - startTime >= WARMUP_TIME) {
        state = RUN;
        startTime = now;
        Serial.println("SENSOR SIAP");
      }
      break;

    case RUN: {
      digitalWrite(LED_B, HIGH);
      int value = analogRead(PIN_ADC);

      if (now - lastBle >= BLE_INTERVAL) {
        sendBLE("ADC=" + String(value));
        lastBle = now;
      }

      if (value >= 3700) {
        Serial.println("BAHAYA");
        setColor(1,0,0);
      } else if (value >= 2700) {
        Serial.println("WASPADA");
        setColor(0,0,1);
      } else if (value >= 844) {
        Serial.println("AMAN");
        setColor(0,1,0);
      } else {
        Serial.println("SENSOR TIDAK MENDETEKSI");
        setColor(0,0,0);
      }


      if (now - startTime >= RUN_TIME) {
        state = OFF;
      }
      break;
    }

    case OFF: {
      setColor(0,0,0);
      sendBLE("STATE=off");

      /* contoh file */
      const char fileData[] = "LOG DATA SENSOR\nEND\n";
      sendFileBLE((uint8_t*)fileData, sizeof(fileData));

#if SIM_WOKWI
      if (digitalRead(PIN_BUTTON) == LOW) {
        delay(300);
        state = IDLE;
      }
#else
      delay(2000);
      esp_sleep_enable_gpio_wakeup();
      gpio_wakeup_enable((gpio_num_t)PIN_BUTTON, GPIO_INTR_LOW_LEVEL);
      esp_deep_sleep_start();
#endif
      break;
    }
  }

  delay(100);
}