/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0""

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:  

*

*/

#include "cptaskexecutor.h"

#include <QMutexLocker>

#include <QDebug>

#include <QtAlgorithms>

#include <QPointer>

static QPointer<CpTaskExecutor> g_instance;

CpTaskExecutor *CpTaskExecutor::globalInstance()

{

    if (!g_instance) {

        g_instance = new CpTaskExecutor();

    }

    return g_instance.data();

}

void CpTaskExecutor::destroyGlobalInstance()

{

    delete g_instance.data();

}

CpTaskExecutor::CpTaskExecutor(QObject *parent /*=0*/) 

: QThread(parent), mStopped(false)

{

}

CpTaskExecutor::~CpTaskExecutor()

{

    stop();

}

bool CpTaskExecutor::runTask(CpTask *task,bool append /*= false*/)

{

    if (mStopped) {

        if (isRunning()) {

            qDebug() << "thread in stopping process...can not run task.\r\n";

            return false;

        }

        mStopped = false;

    }

    if (task) {

        {

            QMutexLocker locker(&mMutex);

            if (append) {

                mTasks.append(task);

            }

            else {

                mTasks.insert(0,task);

            }

        }

        if (!isRunning()) {

            qDebug() << "isRunning() == false, call start()\r\n";

            start();

        }

    }

    return true;

}

void CpTaskExecutor::stop()

{

    if (!mStopped && isRunning() ) {

       mStopped = true;

       removeTasks();

       wait(); //wait for finished

    }

}

void CpTaskExecutor::removeTasks()

{

    QMutexLocker locker(&mMutex);

    QList<CpTask*>::const_iterator begin(mTasks.begin());

    QList<CpTask*>::const_iterator end(mTasks.end());

    for (; begin != end; ++begin) {

        if ((*begin)->autoDelete()) {

            delete (*begin);

        }

    }

    mTasks.clear();

}

void CpTaskExecutor::run()

{

    while (!mStopped) {

        CpTask *task = 0;

        {

            QMutexLocker locker(&mMutex);

            if (mTasks.isEmpty()) {

                break;

            }

            task = mTasks.takeFirst();

        }

        try {

            task->execute(&mStopped);

            task->complete(&mStopped);

        }catch(...) {

            qDebug() << "excetion occur when running task\r\n";           

        }

        if (task->autoDelete()) {

            delete task;

        }

    }

}

bool CpTaskExecutor::toFront(CpTask *task)

{

    QMutexLocker locker(&mMutex);

    QList<CpTask*>::iterator foundIterator = ::qFind(mTasks.begin(),mTasks.end(),task);

    if (foundIterator == mTasks.end()) {

        return false;

    }

    mTasks.erase(foundIterator);

    mTasks.insert(0,task);

    return true;

}

//End of File