/**
   FreeRTOS Counting Semaphore Challenge

   Challenge: use a mutex and counting semaphores to protect the shared buffer
   so that each number (0 throguh 4) is printed exactly 3 times to the Serial
   monitor (in any order). Do not use queues to do this!

   Hint: you will need 2 counting semaphores in addition to the mutex, one for
   remembering number of filled slots in the buffer and another for
   remembering the number of empty slots in the buffer.

   Date: January 24, 2021
   Author: Shawn Hymel
   License: 0BSD
*/

// You'll likely need this on vanilla FreeRTOS
//#include <semphr.h>

// Use only core 1 for demo purposes
#if CONFIG_FREERTOS_UNICORE
static const BaseType_t app_cpu = 0;
#else
static const BaseType_t app_cpu = 1;
#endif

// Settings
// enum {BUF_SIZE = 5};                  // Size of buffer array
static const int num_prod_tasks = 5;  // Number of producer tasks
static const int num_cons_tasks = 2;  // Number of consumer tasks
static const int num_writes = 3;      // Num times each producer writes to buf

// Globals
//static int buf[BUF_SIZE];             // Shared buffer
static int producerWorkload[num_prod_tasks] = {0,0,0,0,0};

static int head = 0;                  // Writing index to buffer
static int tail = 0;                  // Reading index to buffer
static SemaphoreHandle_t bin_sem;     // Waits for parameter to be read
SemaphoreHandle_t sem_empty;     // Waits for parameter to be read
SemaphoreHandle_t mutex;     // Waits for parameter to be read

static const uint8_t msg_queue_len = 5;
static QueueHandle_t msg_queue;

/*


1. show the number of items a worker has pushed to the queue.

*/


//*****************************************************************************
// Tasks

// Producer: write a given number of times to shared buffer
void producer(void *parameters) {

  // Copy the parameters into a local variable
  int num = *(int *)parameters;

  // Release the binary semaphore
  xSemaphoreGive(bin_sem);


  // Fill shared buffer with task number
  for (int i = 0; i < num_writes; i++) {

    // Wait for empty slot in buffer to be available
    xQueueSend(msg_queue, (void *)&num, portMAX_DELAY);

    xSemaphoreTake(mutex, portMAX_DELAY);
    Serial.print("\n\rproducer: ");
    Serial.println(num);
    producerWorkload[num] +=1;
    xSemaphoreGive(mutex);

  }

  // vTaskDelay(1000 / portTICK_PERIOD_MS);


  // Delete self task
  vTaskDelete(NULL);
}

void showProducers(void *parameters) {//void *parameters
  char task_name[20];

for (int i =0; i<num_prod_tasks; i++){
       sprintf(task_name, "%d: %d | ",i, producerWorkload[i]);
 
}
Serial.println('task_name');
}

// Consumer: continuously read from shared buffer
void consumer(void *parameters) {

  int val;

  // Copy the parameters into a local variable
  int consumerNum = *(int *)parameters;

  // Release the binary semaphore
  xSemaphoreGive(bin_sem);

  // Read from buffer
  while (1) {
    int num;
    xQueueReceive(msg_queue, (void *)&num, portMAX_DELAY);
    // Lock Serial resource with a mutex
    producerWorkload[num] -=1;

    xSemaphoreTake(mutex, portMAX_DELAY);

    Serial.print("\n\rconsumer: ");
    Serial.print(consumerNum);
    Serial.print("  | got: ");
    Serial.println(num);
    

    xSemaphoreGive(mutex);



  }

}

//*****************************************************************************
// Main (runs as its own task with priority 1 on core 1)

void setup() {

  char task_name[12];

  // Configure Serial
  Serial.begin(9600);

  // Wait a moment to start (so we don't miss Serial output)
  vTaskDelay(1000 / portTICK_PERIOD_MS);
  Serial.println();
  Serial.println("---FreeRTOS Semaphore Alternate Solution---");

  // Create mutexes and semaphores before starting tasks
  bin_sem = xSemaphoreCreateBinary();
  mutex = xSemaphoreCreateMutex();
 
  msg_queue = xQueueCreate(msg_queue_len, sizeof(int));

    xTaskCreatePinnedToCore(showProducers,
                            "show producers status",
                            1024,
                            NULL,
                            1,
                            NULL,
                            app_cpu);
  // Start producer tasks (wait for each to read argument)
  for (int i = 0; i < num_prod_tasks; i++) {
    sprintf(task_name, "Producer %d", i);
    Serial.println(task_name);
    xTaskCreatePinnedToCore(producer,
                            task_name,
                            1024,
                            (void *)&i,
                            1,
                            NULL,
                            app_cpu);
    xSemaphoreTake(bin_sem, portMAX_DELAY);
  }
  vTaskDelay(1000 / portTICK_PERIOD_MS);

  // Start consumer tasks
  for (int i = 0; i < num_cons_tasks; i++) {
    sprintf(task_name, "Consumer %d", i);
    Serial.println(task_name);

    xTaskCreatePinnedToCore(consumer,
                            task_name,
                            1024,
                            (void *)&i,
                            1,
                            NULL,
                            app_cpu);
    xSemaphoreTake(bin_sem, portMAX_DELAY);
  }

  // Notify that all tasks have been created
  xSemaphoreTake(mutex, portMAX_DELAY);

  Serial.println("All tasks created");
  xSemaphoreGive(mutex);
}

void loop() {

  // Do nothing but allow yielding to lower-priority tasks
  vTaskDelay(1000 / portTICK_PERIOD_MS);
}