/******************************************************************************
 * Icinga 2                                                                   *
 * Copyright (C) 2012-2015 Icinga Development Team (http://www.icinga.org)    *
 *                                                                            *
 * 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 St, Fifth Floor, Boston, MA 02110-1301, USA.             *
 ******************************************************************************/

#include "icinga/dependency.hpp"
#include "icinga/dependency.tcpp"
#include "icinga/service.hpp"
#include "base/logger.hpp"
#include "base/exception.hpp"
#include <boost/foreach.hpp>
#include <boost/algorithm/string/split.hpp>
#include <boost/algorithm/string/classification.hpp>

using namespace icinga;

REGISTER_TYPE(Dependency);

String DependencyNameComposer::MakeName(const String& shortName, const Object::Ptr& context) const
{
	Dependency::Ptr dependency = dynamic_pointer_cast<Dependency>(context);

	if (!dependency)
		return "";

	String name = dependency->GetChildHostName();

	if (!dependency->GetChildServiceName().IsEmpty())
		name += "!" + dependency->GetChildServiceName();

	name += "!" + shortName;

	return name;
}

Dictionary::Ptr DependencyNameComposer::ParseName(const String& name) const
{
	std::vector<String> tokens;
	boost::algorithm::split(tokens, name, boost::is_any_of("!"));

	if (tokens.size() < 2)
		BOOST_THROW_EXCEPTION(std::invalid_argument("Invalid Dependency name."));

	Dictionary::Ptr result = new Dictionary();
	result->Set("child_host_name", tokens[0]);

	if (tokens.size() > 2) {
		result->Set("child_service_name", tokens[1]);
		result->Set("name", tokens[2]);
	} else {
		result->Set("name", tokens[1]);
	}

	return result;
}

void Dependency::OnConfigLoaded(void)
{
	Value defaultFilter;

	if (GetParentServiceName().IsEmpty())
		defaultFilter = StateFilterUp;
	else
		defaultFilter = StateFilterOK | StateFilterWarning;

	SetStateFilter(FilterArrayToInt(GetStates(), defaultFilter));
}

void Dependency::OnAllConfigLoaded(void)
{
	ObjectImpl<Dependency>::OnAllConfigLoaded();

	Host::Ptr childHost = Host::GetByName(GetChildHostName());

	if (childHost) {
		if (GetChildServiceName().IsEmpty()) {
			Log(LogDebug, "Dependency")
			    << "Dependency '" << GetName() << "' child host '" << GetChildHostName() << ".";
			m_Child = childHost;
		} else {
			Log(LogDebug, "Dependency")
			    << "Dependency '" << GetName() << "' child host '" << GetChildHostName() << "' service '" << GetChildServiceName() << "' .";
			m_Child = childHost->GetServiceByShortName(GetChildServiceName());
		}
	}
	
	if (!m_Child)
		BOOST_THROW_EXCEPTION(ScriptError("Dependency '" + GetName() + "' references a child host/service which doesn't exist.", GetDebugInfo()));

	m_Child->AddDependency(this);

	Host::Ptr parentHost = Host::GetByName(GetParentHostName());

	if (parentHost) {
		if (GetParentServiceName().IsEmpty()) {
			Log(LogDebug, "Dependency")
			    << "Dependency '" << GetName() << "' parent host '" << GetParentHostName() << ".";
			m_Parent = parentHost;
		} else {
			Log(LogDebug, "Dependency")
			    << "Dependency '" << GetName() << "' parent host '" << GetParentHostName() << "' service '" << GetParentServiceName() << "' .";
			m_Parent = parentHost->GetServiceByShortName(GetParentServiceName());
		}
	}
	
	if (!m_Parent)
		BOOST_THROW_EXCEPTION(ScriptError("Dependency '" + GetName() + "' references a parent host/service which doesn't exist.", GetDebugInfo()));

	m_Parent->AddReverseDependency(this);
}

void Dependency::Stop(bool runtimeRemoved)
{
	ObjectImpl<Dependency>::Stop(runtimeRemoved);

	GetChild()->RemoveDependency(this);
	GetParent()->RemoveReverseDependency(this);
}

bool Dependency::IsAvailable(DependencyType dt) const
{
	Checkable::Ptr parent = GetParent();

	Host::Ptr parentHost;
	Service::Ptr parentService;
	tie(parentHost, parentService) = GetHostService(parent);

	/* ignore if it's the same checkable object */
	if (parent == GetChild()) {
		Log(LogNotice, "Dependency")
		    << "Dependency '" << GetName() << "' passed: Parent and child " << (parentService ? "service" : "host") << " are identical.";
		return true;
	}

	/* ignore pending  */
	if (!parent->GetLastCheckResult()) {
		Log(LogNotice, "Dependency")
		    << "Dependency '" << GetName() << "' passed: Parent " << (parentService ? "service" : "host") << " '" << parent->GetName() << "' hasn't been checked yet.";
		return true;
	}

	if (GetIgnoreSoftStates()) {
		/* ignore soft states */
		if (parent->GetStateType() == StateTypeSoft) {
			Log(LogNotice, "Dependency")
			    << "Dependency '" << GetName() << "' passed: Parent " << (parentService ? "service" : "host") << " '" << parent->GetName() << "' is in a soft state.";
			return true;
		}
	} else {
		Log(LogNotice, "Dependency")
		    << "Dependency '" << GetName() << "' failed: Parent " << (parentService ? "service" : "host") << " '" << parent->GetName() << "' is in a soft state.";
	}

	int state;

	if (parentService)
		state = ServiceStateToFilter(parentService->GetState());
	else
		state = HostStateToFilter(parentHost->GetState());

	/* check state */
	if (state & GetStateFilter()) {
		Log(LogNotice, "Dependency")
		    << "Dependency '" << GetName() << "' passed: Parent " << (parentService ? "service" : "host") << " '" << parent->GetName() << "' matches state filter.";
		return true;
	}

	/* ignore if not in time period */
	TimePeriod::Ptr tp = GetPeriod();
	if (tp && !tp->IsInside(Utility::GetTime())) {
		Log(LogNotice, "Dependency")
		    << "Dependency '" << GetName() << "' passed: Outside time period.";
		return true;
	}

	if (dt == DependencyCheckExecution && !GetDisableChecks()) {
		Log(LogNotice, "Dependency")
		    << "Dependency '" << GetName() << "' passed: Checks are not disabled.";
		return true;
	} else if (dt == DependencyNotification && !GetDisableNotifications()) {
		Log(LogNotice, "Dependency")
		    << "Dependency '" << GetName() << "' passed: Notifications are not disabled";
		return true;
	}

	Log(LogNotice, "Dependency")
	    << "Dependency '" << GetName() << "' failed. Parent "
	    << (parentService ? "service" : "host") << " '" << parent->GetName() << "' is "
	    << (parentService ? Service::StateToString(parentService->GetState()) : Host::StateToString(parentHost->GetState()));

	return false;
}

Checkable::Ptr Dependency::GetChild(void) const
{
	return m_Child;
}

Checkable::Ptr Dependency::GetParent(void) const
{
	return m_Parent;
}

TimePeriod::Ptr Dependency::GetPeriod(void) const
{
	return TimePeriod::GetByName(GetPeriodRaw());
}

void Dependency::ValidateStates(const Array::Ptr& value, const ValidationUtils& utils)
{
	ObjectImpl<Dependency>::ValidateStates(value, utils);

	int sfilter = FilterArrayToInt(value, 0);

	if (GetParentServiceName().IsEmpty() && (sfilter & ~(StateFilterUp | StateFilterDown)) != 0)
		BOOST_THROW_EXCEPTION(ValidationError(this, boost::assign::list_of("states"), "State filter is invalid for host dependency."));

	if (!GetParentServiceName().IsEmpty() && (sfilter & ~(StateFilterOK | StateFilterWarning | StateFilterCritical | StateFilterUnknown)) != 0)
		BOOST_THROW_EXCEPTION(ValidationError(this, boost::assign::list_of("states"), "State filter is invalid for service dependency."));
}

