//--------------------------------------------------------------------------------
// <copyright file="SCPExecutor.h" company="LiquidRobotics">
//
// Copyright (c) 2014 Liquid Robotics, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
// This software is associated with a release.  Liquid Robotics makes no
// representation that the design, interfaces or component distribution will
// remain unchanged in future releases.
//
// </copyright>
//
// <summary>
//   Declarations for the SCPExecutor class, which is responsible for periodically
//	 starting a PPP session, reading a file with a standard name and then executing
//   it, then disconnecting.
// </summary>
//
// <owner>Mike Cookson</owner>
//--------------------------------------------------------------------------------

#ifndef __SCPEEXECUTOR_H__
#define __SCPEEXECUTOR_H__

#include "LqrSMACAsynchronousProcessExecutor.h"
#include "PPPHost.h"
#include "SCPExecutorSettings.h"
#include "LqrSMACByteArray.h"
#include "LqrSMACLogger.h"
#include "LqrSMACSemaphore.h"
#include "LqrSMACSharedLib.h"
#include "LqrSMACWaitableThreadSafeQueue.h"
#include <string>
#include <boost/shared_ptr.hpp>
#include <boost/signals2.hpp>

namespace LiquidRobotics {
namespace SMACFramework {
	class LineMachine;
}
}

namespace LiquidRobotics {
namespace PPPHostLib {

class SHARED_LIB_PUBLIC SCPExecutor : boost::noncopyable
{
public:

	DECLARE_EXCEPTION(AbortDelay, std::runtime_error);
	DECLARE_EXCEPTION(AlreadyInitialized, std::runtime_error);
	DECLARE_EXCEPTION(NotInitialized, std::runtime_error);
	DECLARE_EXCEPTION(ShutdownRequested, std::runtime_error);

	typedef LiquidRobotics::SMACFramework::AsynchronousProcessExecutor AsynchronousProcessExecutor;
	typedef PPPHost::ConnectionStatus ConnectionStatus;
	typedef LiquidRobotics::SMACFramework::Logger Logger;
	typedef LiquidRobotics::PPPHostLib::PPPHost::ConnectionSignalType ConnectionSignalType;
	typedef boost::unique_lock<SCPExecutor> Lock;
	typedef boost::recursive_mutex Mutex;
	typedef boost::unique_lock<Mutex> MutexLock;
	typedef LiquidRobotics::SMACFramework::LineMachine LineMachine;
	typedef boost::shared_ptr<SCPExecutor> Ptr;
	typedef std::string string;
	typedef boost::signals2::scoped_connection ScopedConnection;
	typedef boost::shared_ptr<ScopedConnection> ScopedConnectionPtr;

	SCPExecutor(const SCPExecutorSettings& _settings, Logger::Ptr _logger = Logger::Ptr());

	virtual ~SCPExecutor();

	void Initialize();
	void QueueConnect();
	void Shutdown();
	ScopedConnectionPtr Subscribe(ConnectionSignalType::slot_type slot);

	// Lockable concept used internally and usable by external actors
	virtual void lock();
	virtual bool try_lock();
	virtual void unlock();


	struct QueueEntry
	{
		enum Type
		{
			UNSPECIFIED = -1,
			ABORT_DELAY,
			CONNECTION_STATE_CHANGE,
			SHUT_DOWN,
			SCP_EXITED,
			SCP_OUTPUT,
			USER_OUTPUT,
			USER_PROGRAM_EXITED
		};

		QueueEntry(Type _type)
		: type(_type)
		{
		}

		QueueEntry(Type _type, const ConnectionStatus& _newStatus)
		: type(_type)
		, newStatus(_newStatus)
		{
		}

		QueueEntry(Type _type, const int& _resultCode)
		: type(_type)
		, resultCode(_resultCode)
		{
		}

		QueueEntry(Type _type, const string& _line)
		: type(_type)
		, line(_line)
		{
		}

		Type type;
		ConnectionStatus newStatus;						// the new connection status
		int resultCode;									// exit code from process
		string line;									// line received
	};

private:

	typedef LiquidRobotics::SMACFramework::ByteArray ByteArray;
	typedef LiquidRobotics::SMACFramework::Semaphore Semaphore;
	typedef LiquidRobotics::SMACFramework::WaitableThreadSafeQueue<QueueEntry> QueueType;

	friend class boost::detail::thread_data<boost::reference_wrapper<SCPExecutor> >;

	void APEExitHandler(AsynchronousProcessExecutor& sender, int resultCode);
	void APEReportHandler(AsynchronousProcessExecutor& sender, const ByteArray& dataReceived, bool fromStdErr);
	void BackgroundThread();
	void Connect();
	void Delay(float seconds, const string& reason);
	void Disconnect();
	float GetNextCallInterval();
	void LineHandler(LineMachine& sender, const string& receivedLine);
	void PPPHostCallback(PPPHost& sender, ConnectionStatus connectionStatus);
	bool RunSCPVerb();
	void RunUserCommand();

	Mutex mutex;
	ConnectionSignalType connectionStateChanged;
	const SCPExecutorSettings settings;
	bool runningSCP;
	Logger::Ptr logger;
	PPPHost::Ptr pppHost;
	QueueType queue;
	ScopedConnectionPtr pppConnection;
	LineMachine::Ptr lineMachine;
	ScopedConnectionPtr lineMachineConnection;
	boost::thread* pThread;
};

SHARED_LIB_PUBLIC std::ostream& operator<<(std::ostream& out, const SCPExecutor::QueueEntry::Type& entryType);

}
}

#endif
