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

// constants won't change. They're used here to set pin numbers:
const int buttonPin = 2;  // the number of the pushbutton pin
const int ledhijau = 4;    // the number of the LED pin
const int ledmerah = 3;    // the number of the LED pin
const int trigPin = 6;
const int echoPin = 5;
const int ldrPin = A0;

// Create semaphore 
SemaphoreHandle_t  sema_v; 

// variables will change:
int buttonState = 0;  // variable for reading the pushbutton status
long duration;
int distance;
int intensitas;
String cahaya;
bool stopTasks = false;

TaskHandle_t Handle_aTask; //membaca sensor ultrasonic
TaskHandle_t Handle_bTask; //membaca sensor ldr 
// TaskHandle_t Handle_dTask;


//membaca sensor ultrasonic
void aTask(void* pvParameters) {
  (void) pvParameters;

  for (;;) 
    {
    if (xSemaphoreTake(sema_v, portMAX_DELAY) == pdPASS) 
    {
          digitalWrite(ledhijau, LOW);
          digitalWrite(ledmerah, HIGH);
          Serial.println("Task A Received Semaphore");
          // Clears the trigPin
          digitalWrite(trigPin, LOW);
          delayMicroseconds(2);
          // Sets the trigPin on HIGH state for 10 micro seconds
          digitalWrite(trigPin, HIGH);
          delayMicroseconds(10);
          digitalWrite(trigPin, LOW);
          // Reads the echoPin, returns the sound wave travel time in microseconds
          duration = pulseIn(echoPin, HIGH);
          // Calculating the distance
          distance = duration * 0.034 / 2;
          // Prints the distance on the Serial Monitor
          // Serial.print("Distance: ");
          // Serial.println(distance);
          Serial.print("Jarak:");
          Serial.println(distance);
    }
}
}
//membaca sensor ldr
void bTask(void* pvParameters) {
  (void) pvParameters;
  for (;;) 
    {
      if (xSemaphoreTake(sema_v, portMAX_DELAY) == pdPASS)
    {
      digitalWrite(ledmerah, LOW);
      digitalWrite(ledhijau, HIGH);
      Serial.println("Task B Received Semaphore");
      intensitas = analogRead(ldrPin);
      if(intensitas <= 200){ 
        cahaya = "Terang";
      }else{
        cahaya = "gelap";
      }
      Serial.print("Cahaya: " );
      Serial.println(cahaya);
      
    }
}}


void setup() {
  pinMode(ledhijau, OUTPUT);
  pinMode(ledmerah, OUTPUT);
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
  pinMode(echoPin, INPUT); // Sets the echoPin as an Input
  Serial.begin(9600); // Starts the serial communication
  pinMode(buttonPin, INPUT);

  xTaskCreate(aTask,     "Task A",       256, NULL,tskIDLE_PRIORITY + 1, &Handle_aTask);
  xTaskCreate(bTask,     "Task B",       256, NULL,tskIDLE_PRIORITY + 1, &Handle_bTask);
  
  sema_v = xSemaphoreCreateBinary();
  if(sema_v !=NULL)
  {
  attachInterrupt(digitalPinToInterrupt(buttonPin), blinkmerah, HIGH);
  }
}

void loop() {
}

void blinkmerah(){  
    Serial.println("ISR interrupt, Semaphore is Given"); 
    BaseType_t  xHigherPriorityTaskWoken  pdFALSE;
    xSemaphoreGiveFromISR(sema_v, &xHigherPriorityTaskWoken); 
}