// $Id$

// ============================================================================
//
// = LIBRARY
//    tests
// 
// = FILENAME
//    Future_Test.cpp
//
// = DESCRIPTION
//    This example tests the ACE Future.
//
// = AUTHOR
//    Andres Kruse <Andres.Kruse@cern.ch> and Douglas C. Schmidt
//    <schmidt@cs.wustl.edu> 
// 
// ============================================================================

#include <math.h>
#include "ace/Task.h"

#include "ace/Synch.h"
#include "ace/Message_Queue.h"
#include "ace/Future.h"
#include "ace/Method_Object.h"
#include "ace/Activation_Queue.h"
#include "ace/Auto_Ptr.h"
#include "test_config.h"

#if defined (ACE_HAS_THREADS)

typedef ACE_Atomic_Op<ACE_Thread_Mutex, u_long> ATOMIC_INT;

// a counter for the tasks..
static ATOMIC_INT task_count (0);

// a counter for the futures..
static ATOMIC_INT future_count (0);
static ATOMIC_INT future_no (0);

// a counter for the capsules..
static ATOMIC_INT capsule_count (0);
static ATOMIC_INT capsule_no (0);

// a counter for the method objects...
static ATOMIC_INT methodobject_count (0);
static ATOMIC_INT methodobject_no (0);

class Scheduler : public ACE_Task<ACE_MT_SYNCH>
  // = TITLE
  //     Active Object Scheduler.
{
  friend class Method_ObjectWork;
public:
  Scheduler (const char *, Scheduler * = 0);
  ~Scheduler (void);

  virtual int open (void *args = 0);
  virtual int close (u_long flags = 0);
  virtual int put (ACE_Message_Block *mb, ACE_Time_Value *tv = 0);
  virtual int svc (void);

  ACE_Future<double> work (double param, int count);
  ACE_Future<const char*> name (void);
  void end (void);

  double work_i (double, int);
  const char *name_i (void);

private:
  char *name_;
  ACE_Activation_Queue activation_queue_;
  Scheduler *scheduler_;
};

class Method_Object_work : public ACE_Method_Object
  // = TITLE
  //     Reification of the <work> method.
{
public:
  Method_Object_work (Scheduler *, double, int, ACE_Future<double> &);
  ~Method_Object_work (void);
  virtual int call (void);

private:
  Scheduler *scheduler_;
  double param_;
  int count_;
  ACE_Future<double> future_result_;
};

Method_Object_work::Method_Object_work (Scheduler* new_Scheduler,
				        double new_param, 
				        int new_count, 
					ACE_Future<double> &new_result)
  :   scheduler_ (new_Scheduler),
      param_ (new_param),
      count_ (new_count),
      future_result_ (new_result)
{ 
  ACE_DEBUG ((LM_DEBUG,
	      "(%t) Method_Object_work created\n"));
}

Method_Object_work::~Method_Object_work (void)
{
  ACE_DEBUG ((LM_DEBUG, "(%t) Method_Object_work will be deleted.\n"));
}


int
Method_Object_work::call (void)
{
  return this->future_result_.set (this->scheduler_->work_i (this->param_, this->count_));
}

class Method_Object_name : public ACE_Method_Object
  // = TITLE
  //     Reification of the <name> method.
{
public:
  Method_Object_name (Scheduler *, ACE_Future<const char*> &);
  ~Method_Object_name (void);
  virtual int call (void);

private:
  Scheduler *scheduler_;
  ACE_Future<const char*> future_result_;
};

Method_Object_name::Method_Object_name (Scheduler *new_scheduler,
					ACE_Future<const char*> &new_result)
  : scheduler_ (new_scheduler),
    future_result_ (new_result)
{
  ACE_DEBUG ((LM_DEBUG,
	      "(%t) Method_Object_name created\n"));
};

Method_Object_name::~Method_Object_name (void)
{
  ACE_DEBUG ((LM_DEBUG, 
	      "(%t) Method_Object_name will be deleted.\n"));
}

int
Method_Object_name::call (void)
{
  return future_result_.set (scheduler_->name_i ());
}

class Method_Object_end : public ACE_Method_Object
  // = TITLE
  //     Reification of the <end> method.
{
public:
  Method_Object_end (Scheduler *new_Scheduler): scheduler_ (new_Scheduler) {}
  ~Method_Object_end (void) {}
  virtual int call (void) { this->scheduler_->close (); return -1; }

private:
  Scheduler *scheduler_;
};

// constructor
Scheduler::Scheduler (const char *newname, Scheduler *new_Scheduler)
{
  ACE_NEW (this->name_, char[ACE_OS::strlen (newname) + 1]);
  ACE_OS::strcpy ((char *) this->name_, newname);
  this->scheduler_ = new_Scheduler;
  ACE_DEBUG ((LM_DEBUG, "(%t) Scheduler %s created\n", this->name_));
}

// Destructor
Scheduler::~Scheduler (void)
{
  ACE_DEBUG ((LM_DEBUG, "(%t) Scheduler %s will be destroyed\n", this->name_));
}

// open
int 
Scheduler::open (void *)
{
  task_count++;
  ACE_DEBUG ((LM_DEBUG, "(%t) Scheduler %s open\n", this->name_));
  return this->activate (THR_BOUND);
}

// close
int 
Scheduler::close (u_long)
{
  ACE_DEBUG ((LM_DEBUG, "(%t) Scheduler %s close\n", this->name_));
  task_count--;
  return 0;
}

// put... ??
int 
Scheduler::put (ACE_Message_Block *, ACE_Time_Value *)
{
  return 0;
}

// service..
int 
Scheduler::svc (void)
{
  ACE_NEW_THREAD;

  for (;;) 
    {
      // Dequeue the next method object (we use an auto pointer in
      // case an exception is thrown in the <call>).
      auto_ptr<ACE_Method_Object> mo (this->activation_queue_.dequeue ());

      ACE_DEBUG ((LM_DEBUG, "(%t) calling method object\n"));
      // Call it.
      if (mo->call () == -1)
	break;
      // Destructor automatically deletes it.
    }

  /* NOTREACHED */
  return 0;
}

void 
Scheduler::end (void)
{
  this->activation_queue_.enqueue (new Method_Object_end (this));
}


// Here's where the Work takes place.
double 
Scheduler::work_i (double param, 
		   int count)
{
  double x = 0, y = 0;
  
  // @@ We should probably do something fun here, like compute the
  // Fibonacci sequence or something.

  for (int j = 0; j < count; j++) 
    {
      x = x + param;
      y = y + ::sin (x);
    }

  return y;
}

const char *
Scheduler::name_i (void)
{
  char *the_name;

  ACE_NEW_RETURN (the_name, char[ACE_OS::strlen (this->name_) + 1], 0);
  ACE_OS::strcpy (the_name, this->name_);

  return the_name;
}

ACE_Future<const char *> 
Scheduler::name (void)
{
  if (this->scheduler_) 
    // Delegate to the Scheduler.
    return this->scheduler_->name ();
  else 
    {
      ACE_Future<const char*> new_future;

      // @@ What happens if new fails here?
      this->activation_queue_.enqueue 
	(new Method_Object_name (this, new_future));

      return new_future;
    }
}

ACE_Future<double> 
Scheduler::work (double newparam, int newcount)
{
  if (this->scheduler_) {
    return this->scheduler_->work (newparam, newcount);
  }
  else {
    ACE_Future<double> new_future;

    this->activation_queue_.enqueue
      (new Method_Object_work (this, newparam, newcount, new_future));
    return new_future;
  }
}

// @@ These values should be set by the command line options!

// Total number of iterations to <work>
static int n_iterations = 50000;

// Total number of loops.
static int n_loops = 100;

#if defined (ACE_TEMPLATES_REQUIRE_SPECIALIZATION)
template class ACE_Atomic_Op<ACE_Thread_Mutex, u_long>;
#endif /* ACE_TEMPLATES_REQUIRE_SPECIALIZATION */

#endif /* ACE_HAS_THREADS */

int
main (int, char *[]) 
{
  ACE_START_TEST ("Future_Test");

#if defined (ACE_HAS_THREADS)
  Scheduler *andres, *peter, *helmut, *matias;

  // Create active objects..  
  // @@ Should "open" be subsumed within the constructor of
  // Scheduler()?
  ACE_NEW_RETURN (andres, Scheduler ("andres"), -1);
  andres->open ();
  ACE_NEW_RETURN (peter, Scheduler ("peter"), -1);
  peter->open ();
  ACE_NEW_RETURN (helmut, Scheduler ("helmut"), -1);
  helmut->open ();

  // Matias passes all asynchronous method calls on to Andres...
  ACE_NEW_RETURN (matias, Scheduler ("matias", andres), -1);
  matias->open ();

  for (int i = 0; i < n_loops; i++) 
    {
      {
	ACE_Future<double> fresulta, fresultb, fresultc, fresultd, fresulte;
	ACE_Future<const char*> fname;

	ACE_DEBUG ((LM_DEBUG, "(%t) going to do a non-blocking call\n"));

	fresulta = andres->work (0.01, 100 + (n_iterations * (i % 2)));
	fresultb = peter->work (0.01, 100 + (n_iterations * (i % 2)));
	fresultc = helmut->work (0.01, 100 + (n_iterations * (i % 2)));
	fresultd = matias->work (0.02, 100 + (n_iterations * (i % 2)));
	fname = andres->name ();

	// see if the result is available...
	if (fresulta.ready ())
	  ACE_DEBUG ((LM_DEBUG, "(%t) wow.. work is ready.....\n"));

	ACE_DEBUG ((LM_DEBUG, "(%t) non-blocking call done... now blocking...\n"));

	// Save the result of fresulta.

	fresulte = fresulta;

	if (i % 3 == 0) 
	  {
	    // Every 3rd time... disconnect the futures...
	    // but "fresulte" should still contain the result...
	    fresulta.cancel (10.0);
	    fresultb.cancel (20.0);
	    fresultc.cancel (30.0);
	    fresultd.cancel (40.0);
	  }

	double resulta = 0, resultb = 0, resultc = 0, resultd = 0, resulte = 0;

	fresulta.get (resulta);
	fresultb.get (resultb);
	fresultc.get (resultc);
	fresultd.get (resultd);
	fresulte.get (resulte);

	ACE_DEBUG ((LM_DEBUG, "(%t) result a %f\n", resulte));
	ACE_DEBUG ((LM_DEBUG, "(%t) result b %f\n", resulta));
	ACE_DEBUG ((LM_DEBUG, "(%t) result c %f\n", resultb));
	ACE_DEBUG ((LM_DEBUG, "(%t) result d %f\n", resultc));
	ACE_DEBUG ((LM_DEBUG, "(%t) result e %f\n", resultd));

	const char *name;

	fname.get (name);

	ACE_DEBUG ((LM_DEBUG, "(%t) name %s\n", name));

      }

      ACE_DEBUG ((LM_DEBUG,
		  "(%t) task_count %d future_count %d capsule_count %d methodobject_count %d\n",
		  (u_long) task_count,
		  (u_long) future_count,
		  (u_long) capsule_count,
		  (u_long) methodobject_count));
    }

  // Close things down.
  andres->end ();
  peter->end ();
  helmut->end ();
  matias->end ();

  ACE_OS::sleep (2);
  
  ACE_DEBUG ((LM_DEBUG,
	      "(%t) task_count %d future_count %d capsule_count %d methodobject_count %d\n",
	      (u_long) task_count,
	      (u_long) future_count,
	      (u_long) capsule_count,
	      (u_long) methodobject_count));

  ACE_DEBUG ((LM_DEBUG,"(%t) th' that's all folks!\n"));

  ACE_OS::sleep (5);
#else
  ACE_ERROR ((LM_ERROR, "threads not supported on this platform\n"));
#endif /* ACE_HAS_THREADS */
  ACE_END_TEST;
  return 0;
}