// license: public domain
// authors: jonas.sundstrom@kirilla.com

#include <GenericThread.h>

GenericThread::GenericThread(const char * a_thread_name, int32 a_priority, BMessage * a_message)	
	:
	m_thread_data_store	(a_message),
	m_thread_id			(spawn_thread (private_thread_function, a_thread_name, a_priority, this)),
	m_execute_unit		(create_sem(1, "m_execute_unit")),
	m_quit_requested	(false),
	m_thread_is_paused	(false)
{
	if (m_thread_data_store == NULL)
		m_thread_data_store	=	new BMessage();
}

GenericThread::~GenericThread()
{
	kill_thread(m_thread_id);
	
	delete_sem(m_execute_unit);
}

status_t 
GenericThread::ThreadFunction (void)
{
	status_t  status  =  B_OK;
	
	status = ThreadStartup();	// Subclass and override this function
	if (status != B_OK)
	{
		ThreadStartupFailed (status);
		return (status);
		// is this the right thing to do?
	}
	
	while(1)
	{
		if (HasQuitBeenRequested())
		{
			status = ThreadShutdown();	// Subclass and override this function
			if (status != B_OK)
			{
				ThreadShutdownFailed (status);
				return (status);
				// what do we do?
			}
			
			delete this;		// destructor
		}

		BeginUnit();

		status = ExecuteUnit();	// Subclass and override

		if (status != B_OK)
			ExecuteUnitFailed (status); // Subclass and override
		
		EndUnit();	
	}

	return (B_OK);
}

status_t 
GenericThread::ThreadStartup (void)
{
	// This function is virtual.
	// Subclass and override this function.

	return B_OK;
}


status_t 
GenericThread::ExecuteUnit (void)
{
	// This function is virtual.

	// You would normally subclass and override this function
	// as it will provide you with Pause and Quit functionality
	// thanks to the unit management done by GenericThread::ThreadFunction()

	return B_OK;
}

status_t 
GenericThread::ThreadShutdown (void)
{
	// This function is virtual.
	// Subclass and override this function.

	return B_OK;
}

void 
GenericThread::ThreadStartupFailed (status_t a_status)
{
	// This function is virtual.
	// Subclass and override this function.
	
	Quit();
}

void 
GenericThread::ExecuteUnitFailed (status_t a_status)
{
	// This function is virtual.
	// Subclass and override this function.
	
	Quit();
}

void 
GenericThread::ThreadShutdownFailed (status_t a_status)
{
	// This function is virtual.
	// Subclass and override this function.
	
	// (is this good default behaviour?)
}

status_t 
GenericThread::Start (void)
{
	status_t	status	=	B_OK;
	
	if (IsPaused())
	{
		status	=	release_sem (m_execute_unit);
		if (status != B_OK)
			return status;

		m_thread_is_paused	=	false;
	}
	
	status	=	resume_thread (m_thread_id);
	
	return status;
}

int32 
GenericThread::private_thread_function (void * a_simple_thread_ptr)
{
	status_t	status	=	B_OK;

	status	=	((GenericThread *) a_simple_thread_ptr)-> ThreadFunction();

	return (status);
}

BMessage *	
GenericThread::GetDataStore (void)
{
	return	(m_thread_data_store);
}

void
GenericThread::SetDataStore (BMessage * a_message)
{
	m_thread_data_store  =  a_message;
}

status_t	
GenericThread::Pause (bool a_do_block, bigtime_t a_timeout)
{
	status_t	status	=	B_OK;
	
	if (a_do_block)
		status	=	acquire_sem(m_execute_unit); 
			// thread will wait on semaphore
	else
		status	=	acquire_sem_etc(m_execute_unit, 1, B_RELATIVE_TIMEOUT, a_timeout); 
			// thread will timeout

	if (status == B_OK)
	{
		m_thread_is_paused	=	true;
		return (B_OK);
	}
	
	return status;
}

void	
GenericThread::Quit (void)
{
	m_quit_requested	=	true;
}

bool 
GenericThread::HasQuitBeenRequested (void)
{
	return (m_quit_requested);
}

bool	
GenericThread::IsPaused (void)
{
	return (m_thread_is_paused);
}

status_t	
GenericThread::Suspend (void)
{
	return (suspend_thread(m_thread_id));
}

status_t	
GenericThread::Resume (void)
{
	release_sem(m_execute_unit);		// to counteract Pause()
	m_thread_is_paused	=	false;
	
	return (resume_thread(m_thread_id));	// to counteract Suspend()
}

status_t	
GenericThread::Kill (void)
{
	return (kill_thread(m_thread_id));
}

void	
GenericThread::ExitWithReturnValue (status_t a_return_value)
{
	exit_thread(a_return_value);
}

status_t	
GenericThread::SetExitCallback (void (*a_callback)(void*), void * a_data)
{
	return (on_exit_thread(a_callback, a_data));
}

status_t	
GenericThread::WaitForThread (status_t * a_exit_value)
{
	return (wait_for_thread(m_thread_id, a_exit_value));
}

status_t	
GenericThread::Rename (char * a_name)
{
	return (rename_thread(m_thread_id, a_name));
}

status_t	
GenericThread::SendData (int32 a_code, void * a_buffer, size_t a_buffer_size)
{
	return (send_data(m_thread_id, a_code, a_buffer, a_buffer_size));
}

int32	
GenericThread::ReceiveData (thread_id * a_sender, void * a_buffer, size_t a_buffer_size)
{
	return (receive_data(a_sender, a_buffer, a_buffer_size));
}
	
bool	
GenericThread::HasData	(void)
{
	return (has_data(m_thread_id));
}
			
status_t	
GenericThread::SetPriority (int32 a_new_priority)
{
	return (set_thread_priority(m_thread_id, a_new_priority));
}

void	
GenericThread::Snooze (bigtime_t a_microseconds)
{
	Suspend();
	snooze(a_microseconds);
	Resume();
}

void	
GenericThread::SnoozeUntil (bigtime_t a_microseconds, int a_timebase)
{
	Suspend();
	snooze_until(a_microseconds, a_timebase);
	Resume();
}

status_t	
GenericThread::GetInfo (thread_info * a_thread_info)
{
	return (get_thread_info(m_thread_id, a_thread_info));
}

thread_id	
GenericThread::GetThread (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.thread);
}

team_id	
GenericThread::GetTeam (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.team);
}

char *	
GenericThread::GetName (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.name);
}

thread_state	
GenericThread::GetState (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.state);
}

sem_id	
GenericThread::GetSemaphore (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.sem);
}

int32	
GenericThread::GetPriority (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.priority);
}

bigtime_t	
GenericThread::GetUserTime (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.user_time);
}

bigtime_t	
GenericThread::GetKernelTime (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.kernel_time);
}

void *	
GenericThread::GetStackBase (void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.stack_base);
}

void *	
GenericThread::GetStackEnd	(void)
{
	thread_info	t_thread_info;
	GetInfo (& t_thread_info);
	return (t_thread_info.stack_end);
}

void	
GenericThread::BeginUnit (void)
{
	acquire_sem(m_execute_unit); // thread can not be paused until it releases semaphore
}

void	
GenericThread::EndUnit	(void)
{
	release_sem(m_execute_unit); // thread can now be paused
}