// ============================================================================
//  Copyright (C) 2001-2013 by Jozef Starosczyk
//  ixen@copyhandler.com
//
//  This program is free software; you can redistribute it and/or modify
//  it under the terms of the GNU Library General Public License
//  (version 2) as published by the Free Software Foundation;
//
//  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 Library General Public
//  License along with this program; if not, write to the
//  Free Software Foundation, Inc.,
//  59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
// ============================================================================
#include "stdafx.h"
#include "TSQLiteTransaction.h"
#include "TSQLiteException.h"
#include "ErrorCodes.h"
#include "sqlite3/sqlite3.h"

BEGIN_CHCORE_NAMESPACE

namespace sqlite
{
	TSQLiteTransaction::TSQLiteTransaction(const TSQLiteDatabasePtr& spDatabase) :
		m_spDatabase(spDatabase),
		m_bTransactionStarted(false)
	{
		if(!m_spDatabase)
			THROW_SQLITE_EXCEPTION(eErr_InvalidArgument, 0, _T("Invalid database provided"));
		Begin();
	}

	TSQLiteTransaction::~TSQLiteTransaction()
	{
		// try to rollback the transaction; this is the last resort
		if(m_bTransactionStarted && m_spDatabase->GetInTransaction())
		{
			int iResult = sqlite3_exec((sqlite3*)m_spDatabase->GetHandle(), "ROLLBACK TRANSACTION;", NULL, NULL, NULL);
			iResult;
			_ASSERTE(iResult == SQLITE_OK);
			m_spDatabase->SetInTransaction(false);
		}
	}

	void TSQLiteTransaction::Begin()
	{
		if(m_spDatabase->GetInTransaction())
			return;

		if(m_bTransactionStarted)
			THROW_SQLITE_EXCEPTION(eErr_SQLiteCannotBeginTransaction, 0, _T("Transaction already started"));

		int iResult = sqlite3_exec((sqlite3*)m_spDatabase->GetHandle(), "BEGIN TRANSACTION", NULL, NULL, NULL);
		if(iResult != SQLITE_OK)
			THROW_SQLITE_EXCEPTION(eErr_SQLiteCannotBeginTransaction, iResult, _T("Cannot begin transaction"));

		m_spDatabase->SetInTransaction(true);
		m_bTransactionStarted = true;
	}

	void TSQLiteTransaction::Rollback()
	{
		// no transactions whatsoever (even on database)
		if(!m_bTransactionStarted && !m_spDatabase->GetInTransaction())
			THROW_SQLITE_EXCEPTION(eErr_SQLiteCannotRollbackTransaction, 0, _T("Transaction not started"));

		// database has transaction started, but not by this object
		if(!m_bTransactionStarted)
			return;

		int iResult = sqlite3_exec((sqlite3*)m_spDatabase->GetHandle(), "ROLLBACK TRANSACTION;", NULL, NULL, NULL);
		if(iResult != SQLITE_OK)
			THROW_SQLITE_EXCEPTION(eErr_SQLiteCannotRollbackTransaction, iResult, _T("Cannot rollback transaction"));
		m_spDatabase->SetInTransaction(false);
		m_bTransactionStarted = false;
	}

	void TSQLiteTransaction::Commit()
	{
		// no transactions whatsoever (even on database)
		if(!m_bTransactionStarted && !m_spDatabase->GetInTransaction())
			THROW_SQLITE_EXCEPTION(eErr_SQLiteCannotRollbackTransaction, 0, _T("Transaction not started"));

		// database has transaction started, but not by this object
		if(!m_bTransactionStarted)
			return;

		int iResult = sqlite3_exec((sqlite3*)m_spDatabase->GetHandle(), "COMMIT TRANSACTION;", NULL, NULL, NULL);
		if(iResult != SQLITE_OK)
			THROW_SQLITE_EXCEPTION(eErr_SQLiteCannotCommitTransaction, iResult, _T("Cannot commit transaction"));
		m_spDatabase->SetInTransaction(false);
		m_bTransactionStarted = false;
	}
}

END_CHCORE_NAMESPACE