#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/gpio.h"

volatile bool button_pressed = false;

void buttonIsPressed(void *args)
{
  button_pressed = true;
}

void app_main() {

  gpio_config_t button_config = {
    .pin_bit_mask = 1 << 4,
    .mode = GPIO_MODE_INPUT,
    .pull_up_en = GPIO_PULLUP_ENABLE,
    .pull_down_en = GPIO_PULLDOWN_DISABLE,
    .intr_type = GPIO_INTR_NEGEDGE
  };

  gpio_config(&button_config);

  gpio_install_isr_service(0);

  gpio_isr_handler_add(GPIO_NUM_4, buttonIsPressed, NULL);

  while (1) {
    printf("GPIO 4 = %d\n", gpio_get_level(GPIO_NUM_4));
    vTaskDelay(500 / portTICK_PERIOD_MS);
  }
}