#include <Arduino.h>
#include <Arduino_FreeRTOS.h>
#include <semphr.h>

#define BUTTON_PIN 2
#define LED_PIN 13

SemaphoreHandle_t xBinarySemaphore;

void vTaskFunction(void *pvParameters);
void ISR_ButtonPress();

void setup() {
  pinMode(LED_PIN, OUTPUT);
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(BUTTON_PIN), ISR_ButtonPress, FALLING);
  xBinarySemaphore = xSemaphoreCreateBinary();

  if (xBinarySemaphore != NULL) {
    xTaskCreate(
      vTaskFunction,       /* Task function. */
      "Task1",             /* String with name of task. */
      128,                 /* Stack size in bytes. */
      NULL,                /* Parameter passed as input of the task */
      1,                   /* Priority of the task. */
      NULL);               /* Task handle. */
  }
}

void loop() {
  // Do nothing here.
}

void vTaskFunction(void *pvParameters) {
  for (;;) {
    if (xSemaphoreTake(xBinarySemaphore, portMAX_DELAY) == pdTRUE) {
      digitalWrite(LED_PIN, HIGH);
      vTaskDelay(1000 / portTICK_PERIOD_MS);
      digitalWrite(LED_PIN, LOW);
    }
  }
}

void ISR_ButtonPress() {
  Serial.println("Button pressed!");
  BaseType_t xHigherPriorityTaskWoken = pdFALSE;
  xSemaphoreGiveFromISR(xBinarySemaphore, &xHigherPriorityTaskWoken);
  if (xHigherPriorityTaskWoken == pdTRUE) {
    portYIELD_FROM_ISR();
  }
}