#include "esp_sleep.h"

static const gpio_num_t PIN_SWITCH = GPIO_NUM_13;
static const gpio_num_t PIN_LED    = GPIO_NUM_15;

void enterDeepSleep() {
    digitalWrite(PIN_LED, LOW);            // turn LED OFF before sleep
    delay(50);                             // small safety delay

    // Configure wakeup on GPIO13, trigger when LOW (button pressed)
    esp_sleep_enable_ext1_wakeup(
        (1ULL << PIN_SWITCH),
        ESP_EXT1_WAKEUP_ALL_LOW
    );

    esp_deep_sleep_start();                // never returns
}

void setup() {
    pinMode(PIN_LED, OUTPUT);
    digitalWrite(PIN_LED, LOW);

    pinMode(PIN_SWITCH, INPUT_PULLUP);

    // Optional: slow debug
    Serial.begin(115200);
    delay(200);
    Serial.println("Booting in NORMAL MODE");
}

void loop() {
    // check if user pressed button → go to deep sleep
    if (digitalRead(PIN_SWITCH) == LOW) {
        Serial.println("Button pressed → entering DEEP SLEEP");
        delay(1000);
        enterDeepSleep();
    }

    // normal mode: blink LED 1Hz
    digitalWrite(PIN_LED, HIGH);
    delay(250);

    digitalWrite(PIN_LED, LOW);
    delay(250);
}