/* Simple threaded work queue using POSIX threads.
 */
#ifndef eslWORKQUEUE_INCLUDED
#define eslWORKQUEUE_INCLUDED
#include <esl_config.h>

typedef struct {
  pthread_mutex_t  queueMutex;          /* mutex for queue serialization                           */
  pthread_cond_t   readerQueueCond;     /* condition variable used to wake up the producer         */
  pthread_cond_t   workerQueueCond;     /* condition variable used to wake up the consumers        */

  void           **readerQueue;         /* list of objects the the workers have completed          */
  int              readerQueueCnt;      /* number of objects in the queue                          */
  int              readerQueueHead;     /* first object in the queue                               */

  void           **workerQueue;         /* list of objects ready to be processed by worker threads */
  int              workerQueueCnt;      /* number of objects in the queue                          */
  int              workerQueueHead;     /* first object in the queue                               */

  int              queueSize;           /* max number of items a queue will hold                   */
  int              pendingWorkers;      /* number of consumers waiting for work                    */
} ESL_WORK_QUEUE;

typedef struct{
  pthread_mutex_t   queueMutex;    // lock that controls access to the object
  

  // 
  void           **readerQueue; //empty objects waiting for reader to fill them
  int              readerQueueCnt;
  int              readerQueueHead;

  void           **workerQueue;       // Queue of full objects waiting to be processed by workers
  int              workerQueueCnt;
  int              workerQueueHead;

  void           ***workerWaitQueue;   // Queue of workers waiting for readers to fill blocks
  int              workerWaitQueueCnt;
  int              workerWaitQueueHead; 

  void           ***readerWaitQueue;  // Queue of readers waiting for workers to complete blocks
  int              readerWaitQueueCnt;
  int              readerWaitQueueHead;

  int              queueSize;         // max number of items a queue will hold
  int              waitingWorkers;    // Number of wokrers waiting for blocks
  int              waitingReaders;    // number of readers waiting for blocks
} ESL_WORK_QUEUE_QUEUELOCK;


extern ESL_WORK_QUEUE *esl_workqueue_Create(int size);
extern void            esl_workqueue_Destroy(ESL_WORK_QUEUE *queue);

extern ESL_WORK_QUEUE_QUEUELOCK *esl_workqueue_queuelock_Create(int size);
extern void            esl_workqueue_queuelock_Destroy(ESL_WORK_QUEUE_QUEUELOCK *queue);

extern int esl_workqueue_Init    (ESL_WORK_QUEUE *queue, void *ptr);
extern int esl_workqueue_Complete(ESL_WORK_QUEUE *queue);
extern int esl_workqueue_Reset   (ESL_WORK_QUEUE *queue);

extern int esl_workqueue_queuelock_Init    (ESL_WORK_QUEUE_QUEUELOCK *queue, void *ptr);
extern int esl_workqueue_queuelock_Complete(ESL_WORK_QUEUE_QUEUELOCK *queue);
extern int esl_workqueue_queuelock_Reset   (ESL_WORK_QUEUE_QUEUELOCK *queue);

extern int esl_workqueue_Remove(ESL_WORK_QUEUE *queue, void **obj);
extern int esl_workqueue_queuelock_Remove(ESL_WORK_QUEUE_QUEUELOCK *queue, void **obj);

extern int esl_workqueue_ReaderUpdate(ESL_WORK_QUEUE *queue, void *in, void **out);
extern int esl_workqueue_WorkerUpdate(ESL_WORK_QUEUE *queue, void *in, void **out);
extern int esl_workqueue_queuelock_ReaderUpdate(ESL_WORK_QUEUE_QUEUELOCK *queue, void *in, void **out);
extern int esl_workqueue_queuelock_WorkerUpdate(ESL_WORK_QUEUE_QUEUELOCK *queue, void *in, void **out);

extern int esl_workqueue_Dump(ESL_WORK_QUEUE *queue);
extern int esl_workqueue_queuelock_Dump(ESL_WORK_QUEUE_QUEUELOCK *queue);
#endif /*eslWORKQUEUE_INCLUDED*/