/*
 * This file is a part of Winix
 * and is distributed under the 2-Clause BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2012-2022, Tomasz Sowa
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 */
 
#include "job.h"
#include "plugin.h"
#include "log.h"
#include "functions/functions.h"
#include "lock.h"



namespace Winix
{




Job::Job()
{
	jobs_queue_tab.resize(PRIORITY_HIGHEST + 1);
	cur = nullptr;
	functions = nullptr;
	mounts = nullptr;
	load_avg = nullptr;
	req_tab = nullptr;
}


void Job::SetCur(Cur * cur)
{
	this->cur = cur;
}


void Job::SetFunctions(Functions * functions)
{
	this->functions = functions;
}


void Job::SetLoadAvg(LoadAvg * load_avg)
{
	this->load_avg = load_avg;
}


void Job::SetMounts(Mounts * mounts)
{
	this->mounts = mounts;
}


void Job::SetReqTab(std::list<Request> * req_tab)
{
	this->req_tab = req_tab;
}


void Job::CheckPriority(size_t & priority) const
{
	if( priority > PRIORITY_HIGHEST )
		priority = PRIORITY_HIGHEST;
}


// first thread (objects locked)
void Job::Add(pt::Space & job, size_t priority)
{
	CheckPriority(priority);
	JobTask task;
	task.job_type = JobTask::JOB_TYPE_DEFAULT;
	task.job_id = JobTask::JOB_ID_DEFAULT;
	task.job = job;
	jobs_queue_tab[priority].push(task);
	WakeUpThread();
}


// first thread (objects locked)
void Job::Add(Request * request, pt::Space & job, size_t priority)
{
	CheckPriority(priority);
	JobTask task;
	task.job_type = JobTask::JOB_TYPE_REQUEST_CONTINUATION;
	task.job_id = JobTask::JOB_ID_DEFAULT;
	task.request = request;
	task.job = job;
	jobs_queue_tab[priority].push(task);
	WakeUpThread();
}



// first thread (objects locked)
void Job::Add(long job_id, pt::Space & job, size_t priority)
{
	CheckPriority(priority);
	JobTask task;
	task.job_type = JobTask::JOB_TYPE_DEFAULT;
	task.job_id = job_id;
	task.job = job;
	jobs_queue_tab[priority].push(task);
	WakeUpThread();
}


// first thread (objects locked)
void Job::Add(long job_id, Request * request, pt::Space & job, size_t priority)
{
	CheckPriority(priority);
	JobTask task;
	task.job_type = JobTask::JOB_TYPE_REQUEST_CONTINUATION;
	task.job_id = job_id;
	task.request = request;
	task.job = job;
	jobs_queue_tab[priority].push(task);
	WakeUpThread();
}




size_t Job::Size(size_t priority) const
{
	CheckPriority(priority);
	return jobs_queue_tab[priority].size();
}



size_t Job::Size() const
{
size_t sum = 0;

	for(size_t i=0 ; i <= PRIORITY_HIGHEST ; ++i)
		sum += Size(i);

return sum;
}


bool Job::Empty(size_t priority) const
{
	CheckPriority(priority);
	return jobs_queue_tab[priority].empty();
}


bool Job::Empty() const
{
	for(size_t i=0 ; i <= PRIORITY_HIGHEST ; ++i)
		if( !Empty(i) )
			return false;

return true;
}




/*
	second thread
*/

// second thread (objects locked)
bool Job::SignalReceived()
{
	return !Empty();
}


// second thread (objects not locked)
void Job::Do()
{
size_t i = PRIORITY_HIGHEST + 1;
bool is_empty;

	while( i-- > 0 && !IsExitSignal() )
	{
		do
		{
			{
				Winix::Lock lock(synchro);
				is_empty = Empty(i);
			}

			if( !is_empty )
				DoQueue(jobs_queue_tab[i], i);
		}
		while( !is_empty && !IsExitSignal() );
	}
}


// second thread (objects not locked, jobs_queue is not empty)
void Job::DoQueue(JobsQueue & jobs_queue, size_t priority)
{
bool is_empty;

	do
	{
		// references will not be invalidated after insertion to jobs_queue
		// (jobs_queue is std::queue and it uses std::deque by default)
		JobTask * job_task = nullptr;

		{
			Winix::Lock lock(synchro);

			if( !jobs_queue.empty() )
			{
				job_task = &jobs_queue.front();
			}
		}

		if( job_task )
		{
			DoJob(*job_task, priority);

			{
				Winix::Lock lock(synchro);

				jobs_queue.pop();
				is_empty = jobs_queue.empty();
			}
		}
	}
	while( !is_empty && !IsExitSignal() );
}


// second thread (objects not locked)
void Job::DoJob(JobTask & task, size_t priority)
{
	PluginRes res;

	try
	{
		main_log << logsave;

		if( task.job_type == JobTask::JOB_TYPE_REQUEST_CONTINUATION )
		{
			if( task.request )
			{
				Cur local_cur;

				// is this correct? we can read the task.request->session ... from the second thread?
				// chyba tak bo ta struktura zostaje na stosie specjalnie dla joba do uzytku

				local_cur.request = task.request;
				local_cur.session = task.request->session;
				local_cur.mount = task.request->mount;
				cur->request->run_state = Request::RunState::job_run;

				res = plugin->Call(model_connector, &log, &local_cur, WINIX_JOB, &task.job, nullptr, task.job_type, task.job_id);
				log << logsave;

				{
					Winix::Lock lock(synchro);
					cur->request = local_cur.request;
					cur->session = local_cur.session;
					cur->mount = local_cur.mount;
					// winix templates functions uses its own cur (global pointer in TemplatesFunctions namespace)
					// so we have to set it correctly
					DoRequestContinuationJob(task, priority);
				}
			}
			else
			{
				log << log2 << "Job: request continuation task doesn't have a request set, skipping the job and request continuation" << logend;
				log << log2 << "Job: this is an internal error, the request if exists in the queue will never be removed" << logend;
			}
		}
		else
		{
			res = plugin->Call(model_connector, &log, nullptr, WINIX_JOB, &task.job, nullptr, task.job_type, task.job_id);
		}

		log << logsave;

		if( res.res_true == 0 )
		{
			DoWinixJob(task.job); // probably this will be removed
		}
	}
	catch(...)
	{
		log << log2 << "Job: an exception was catched when doing a job" << logend;
	}
}


// second thread (objects locked)
// use main_log (after locking) for the logs to be in the correct order
void Job::DoRequestContinuationJob(JobTask & job_task, size_t priority)
{
	if( cur->request->function )
	{
		main_log << config->log_delimiter << logend;
		main_log << log3 << "Job: making a continuation for request " << cur->request << logend;
		main_log << log4 << "Job: doing directory analysis again" << logend;

		if( functions->ParseOnlyDirs() )
		{
			cur->mount = mounts->CalcCurMount(cur->request);
			cur->request->mount = cur->mount;
			cur->request->run_state = Request::RunState::job_continuation_run;
			functions->ContinueMakeFunction();

			if( cur->request->run_state == Request::RunState::assigned_to_job )
			{
				log << log3 << "Job: this request (" << cur->request << ") has been moved to the job queue again" << logend;
				Add(cur->request->job_id, cur->request, cur->request->job, priority);
			}
		}
		else
		{
			main_log << log4 << "Job: directories have not been correctly prepared, finishing the request" << logend;
			cur->request->http_status = Header::status_500_internal_server_error;
			cur->request->run_state = Request::RunState::prepare_to_finish;
		}
	}
	else
	{
		main_log << log2 << "Job: request continuation task doesn't have a funtion set, return 500 internal error" << logend;
		cur->request->http_status = Header::status_500_internal_server_error;
		cur->request->run_state = Request::RunState::prepare_to_finish;
	}

	if( cur->request->run_state != Request::RunState::assigned_to_job )
	{
		cur->request->FinishRequest(); // jak cur->request->function bedzie null to nie zadzialaja funkcje templajtowe
		load_avg->StopRequest(cur->request);
		cur->request->Clear();
		cur->request->run_state = Request::RunState::finished;
		RemoveOldRequest(cur->request);
	}

	main_log << logendrequest;
}



// second thread (objects not locked)
void Job::DoWinixJob(pt::Space & job)
{
	//log << log1 << "standard winix job: " << job.Text(L"type") << logend;
}



// second thread (objects locked)
// use main_log for the logs to be in the correct order
void Job::RemoveOldRequest(Request * request)
{
	std::list<Request>::iterator i = req_tab->begin();

	while( i != req_tab->end() )
	{
		if( &(*i) == request )
		{
			main_log << log3 << "Job: removing request " << request << logend;
			req_tab->erase(i);
			break;
		}
		else
		{
			++i;
		}
	}
}




} // namespace Winix