/*
 *  This file is part of nzbget
 *
 *  Copyright (C) 2008-2015 Andrey Prygunkov <hugbug@users.sourceforge.net>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * $Revision$
 * $Date$
 *
 */


#include "nzbget.h"
#include "Scheduler.h"
#include "Options.h"
#include "Log.h"
#include "NewsServer.h"
#include "ServerPool.h"
#include "FeedInfo.h"
#include "FeedCoordinator.h"
#include "SchedulerScript.h"

Scheduler::Task::Task(int id, int hours, int minutes, int weekDaysBits, ECommand command, const char* param)
{
	m_id = id;
	m_hours = hours;
	m_minutes = minutes;
	m_weekDaysBits = weekDaysBits;
	m_command = command;
	m_param = param ? strdup(param) : NULL;
	m_lastExecuted = 0;
}

Scheduler::Task::~Task()
{
	free(m_param);
}


Scheduler::Scheduler()
{
	debug("Creating Scheduler");

	m_firstChecked = false;
	m_lastCheck = 0;
	m_taskList.clear();
}

Scheduler::~Scheduler()
{
	debug("Destroying Scheduler");

	for (TaskList::iterator it = m_taskList.begin(); it != m_taskList.end(); it++)
	{
		delete *it;
	}
}

void Scheduler::AddTask(Task* task)
{
	m_taskListMutex.Lock();
	m_taskList.push_back(task);
	m_taskListMutex.Unlock();
}

bool Scheduler::CompareTasks(Scheduler::Task* task1, Scheduler::Task* task2)
{
	return (task1->m_hours < task2->m_hours) ||
		((task1->m_hours == task2->m_hours) && (task1->m_minutes < task2->m_minutes));
}

void Scheduler::FirstCheck()
{
	m_taskListMutex.Lock();
	m_taskList.sort(CompareTasks);
	m_taskListMutex.Unlock();

	// check all tasks for the last week
	CheckTasks();
}

void Scheduler::ServiceWork()
{
	if (!DownloadQueue::IsLoaded())
	{
		return;
	}

	if (!m_firstChecked)
	{
		FirstCheck();
		m_firstChecked = true;
		return;
	}

	m_executeProcess = true;
	CheckTasks();
	CheckScheduledResume();
}

void Scheduler::CheckTasks()
{
	PrepareLog();

	m_taskListMutex.Lock();

	time_t current = time(NULL);

	if (!m_taskList.empty())
	{
		// Detect large step changes of system time
		time_t diff = current - m_lastCheck;
		if (diff > 60*90 || diff < 0)
		{
			debug("Reset scheduled tasks (detected clock change greater than 90 minutes or negative)");

			// check all tasks for the last week
			m_lastCheck = current - 60*60*24*7;
			m_executeProcess = false;

			for (TaskList::iterator it = m_taskList.begin(); it != m_taskList.end(); it++)
			{
				Task* task = *it;
				task->m_lastExecuted = 0;
			}
		}

		time_t localCurrent = current + g_Options->GetLocalTimeOffset();
		time_t localLastCheck = m_lastCheck + g_Options->GetLocalTimeOffset();

		tm tmCurrent;
		gmtime_r(&localCurrent, &tmCurrent);
		tm tmLastCheck;
		gmtime_r(&localLastCheck, &tmLastCheck);

		tm tmLoop;
		memcpy(&tmLoop, &tmLastCheck, sizeof(tmLastCheck));
		tmLoop.tm_hour = tmCurrent.tm_hour;
		tmLoop.tm_min = tmCurrent.tm_min;
		tmLoop.tm_sec = tmCurrent.tm_sec;
		time_t loop = Util::Timegm(&tmLoop);

		while (loop <= localCurrent)
		{
			for (TaskList::iterator it = m_taskList.begin(); it != m_taskList.end(); it++)
			{
				Task* task = *it;
				if (task->m_lastExecuted != loop)
				{
					tm tmAppoint;
					memcpy(&tmAppoint, &tmLoop, sizeof(tmLoop));
					tmAppoint.tm_hour = task->m_hours;
					tmAppoint.tm_min = task->m_minutes;
					tmAppoint.tm_sec = 0;

					time_t appoint = Util::Timegm(&tmAppoint);

					int weekDay = tmAppoint.tm_wday;
					if (weekDay == 0)
					{
						weekDay = 7;
					}

					bool weekDayOK = task->m_weekDaysBits == 0 || (task->m_weekDaysBits & (1 << (weekDay - 1)));
					bool doTask = weekDayOK && localLastCheck < appoint && appoint <= localCurrent;

					//debug("TEMP: 1) m_tLastCheck=%i, tLocalCurrent=%i, tLoop=%i, tAppoint=%i, bWeekDayOK=%i, bDoTask=%i", m_tLastCheck, tLocalCurrent, tLoop, tAppoint, (int)bWeekDayOK, (int)bDoTask);

					if (doTask)
					{
						ExecuteTask(task);
						task->m_lastExecuted = loop;
					}
				}
			}
			loop += 60*60*24; // inc day
			gmtime_r(&loop, &tmLoop);
		}
	}

	m_lastCheck = current;

	m_taskListMutex.Unlock();

	PrintLog();
}

void Scheduler::ExecuteTask(Task* task)
{
	const char* commandName[] = { "Pause", "Unpause", "Pause Post-processing", "Unpause Post-processing",
		"Set download rate", "Execute process", "Execute script",
		"Pause Scan", "Unpause Scan", "Enable Server", "Disable Server", "Fetch Feed" };
	debug("Executing scheduled command: %s", commandName[task->m_command]);

	switch (task->m_command)
	{
		case scDownloadRate:
			if (!Util::EmptyStr(task->m_param))
			{
				g_Options->SetDownloadRate(atoi(task->m_param) * 1024);
				m_downloadRateChanged = true;
			}
			break;

		case scPauseDownload:
		case scUnpauseDownload:
			g_Options->SetPauseDownload(task->m_command == scPauseDownload);
			m_pauseDownloadChanged = true;
			break;

		case scPausePostProcess:
		case scUnpausePostProcess:
			g_Options->SetPausePostProcess(task->m_command == scPausePostProcess);
			m_pausePostProcessChanged = true;
			break;

		case scPauseScan:
		case scUnpauseScan:
			g_Options->SetPauseScan(task->m_command == scPauseScan);
			m_pauseScanChanged = true;
			break;

		case scScript:
		case scProcess:
			if (m_executeProcess)
			{
				SchedulerScriptController::StartScript(task->m_param, task->m_command == scProcess, task->m_id);
			}
			break;

		case scActivateServer:
		case scDeactivateServer:
			EditServer(task->m_command == scActivateServer, task->m_param);
			break;

		case scFetchFeed:
			if (m_executeProcess)
			{
				FetchFeed(task->m_param);
				break;
			}
	}
}

void Scheduler::PrepareLog()
{
	m_downloadRateChanged = false;
	m_pauseDownloadChanged = false;
	m_pausePostProcessChanged = false;
	m_pauseScanChanged = false;
	m_serverChanged = false;
}

void Scheduler::PrintLog()
{
	if (m_downloadRateChanged)
	{
		info("Scheduler: setting download rate to %i KB/s", g_Options->GetDownloadRate() / 1024);
	}
	if (m_pauseDownloadChanged)
	{
		info("Scheduler: %s download", g_Options->GetPauseDownload() ? "pausing" : "unpausing");
	}
	if (m_pausePostProcessChanged)
	{
		info("Scheduler: %s post-processing", g_Options->GetPausePostProcess() ? "pausing" : "unpausing");
	}
	if (m_pauseScanChanged)
	{
		info("Scheduler: %s scan", g_Options->GetPauseScan() ? "pausing" : "unpausing");
	}
	if (m_serverChanged)
	{
		int index = 0;
		for (Servers::iterator it = g_ServerPool->GetServers()->begin(); it != g_ServerPool->GetServers()->end(); it++, index++)
		{
			NewsServer* server = *it;
			if (server->GetActive() != m_serverStatusList[index])
			{
				info("Scheduler: %s %s", server->GetActive() ? "activating" : "deactivating", server->GetName());
			}
		}
		g_ServerPool->Changed();
	}
}

void Scheduler::EditServer(bool active, const char* serverList)
{
	Tokenizer tok(serverList, ",;");
	while (const char* serverRef = tok.Next())
	{
		int id = atoi(serverRef);
		for (Servers::iterator it = g_ServerPool->GetServers()->begin(); it != g_ServerPool->GetServers()->end(); it++)
		{
			NewsServer* server = *it;
			if ((id > 0 && server->GetId() == id) ||
				!strcasecmp(server->GetName(), serverRef))
			{
				if (!m_serverChanged)
				{
					// store old server status for logging
					m_serverStatusList.clear();
					m_serverStatusList.reserve(g_ServerPool->GetServers()->size());
					for (Servers::iterator it2 = g_ServerPool->GetServers()->begin(); it2 != g_ServerPool->GetServers()->end(); it2++)
					{
						NewsServer* server2 = *it2;
						m_serverStatusList.push_back(server2->GetActive());
					}
				}
				m_serverChanged = true;
				server->SetActive(active);
				break;
			}
		}
	}
}

void Scheduler::FetchFeed(const char* feedList)
{
	Tokenizer tok(feedList, ",;");
	while (const char* feedRef = tok.Next())
	{
		int id = atoi(feedRef);
		for (Feeds::iterator it = g_FeedCoordinator->GetFeeds()->begin(); it != g_FeedCoordinator->GetFeeds()->end(); it++)
		{
			FeedInfo* feed = *it;
			if (feed->GetId() == id ||
				!strcasecmp(feed->GetName(), feedRef) ||
				!strcasecmp("0", feedRef))
			{
				g_FeedCoordinator->FetchFeed(!strcasecmp("0", feedRef) ? 0 : feed->GetId());
				break;
			}
		}
	}
}

void Scheduler::CheckScheduledResume()
{
	time_t resumeTime = g_Options->GetResumeTime();
	time_t currentTime = time(NULL);
	if (resumeTime > 0 && currentTime >= resumeTime)
	{
		info("Autoresume");
		g_Options->SetResumeTime(0);
		g_Options->SetPauseDownload(false);
		g_Options->SetPausePostProcess(false);
		g_Options->SetPauseScan(false);
	}
}