#include "filedownloader.h"
#include <QFile>
FileDownloader* FileDownloader::_self=NULL;
QNetworkAccessManager* FileDownloader::m_WebCtrl=NULL;
QList<FileDownloaderTask*>* FileDownloader::m_pendingTasks=NULL;
DownLoadHistory* FileDownloader::m_gui=NULL;
bool FileDownloader::m_noGui=false;
QString FileDownloader::m_serviceName="FileDownloader";

#define _INIT \
    if(Q_UNLIKELY(_self==NULL))\
    {\
        init();\
    }\


int FileDownloader::downloadFile(QUrl fileUrl, const QString &name)
{
    _INIT
    if(QFile::exists(name)|| QFile::exists(name+".part"))
    {
        return -1;
    }
    FileDownloaderTask* task=NULL;
    int ID=_self->getTaskId();
    if(ID!=-1)
    {
        QNetworkRequest request(fileUrl);
        QNetworkReply* reply = m_WebCtrl->get(request);
        if(reply && (reply->error()==QNetworkReply::NoError))
        {
            task=new FileDownloaderTask(reply,ID,name,_self);
            m_pendingTasks->append(task);
            if(!m_noGui)
            {
                m_gui->addElement(new DownloadHistoryElement(task));
            }
        }
        else
        {
            return -1;
        }
    }
    return ID;
}

int FileDownloader::downloadFile(QString fileUrl, const QString &name)
{
    return downloadFile(QUrl(fileUrl),name);
}

QWidget *FileDownloader::getGUI()
{
    return (QWidget*) m_gui;
}

const QString &FileDownloader::serviceName()
{
    return m_serviceName;
}

FileDownloaderTask* FileDownloader::getDownloadTask(int ID)
{
    _INIT
    for(int i=0;i<m_pendingTasks->count();i++)
    {
        if(m_pendingTasks->at(i)->ID()==ID)
            return m_pendingTasks->at(i);
    }
    return NULL;
}

bool FileDownloader::taskIsCompleted(int ID)
{
    return getDownloadTask(ID)->downloadComplete();
}

FileDownloader *FileDownloader::self()
{
    _INIT
    return _self;
}

int FileDownloader::getTaskId()
{
    for(unsigned int i=0;i<INT_MAX;i++)
    {
        bool idValid=true;
        for(int j=0;j<m_pendingTasks->count();j++)
        {
            if(m_pendingTasks->at(j)->ID()==(int)i)
                idValid=false;
        }
        if(idValid)
            return (int)i;
    }
    return -1;
}

void FileDownloader::init(bool noGUI, QObject *parent)
{
    m_noGui=noGUI;
    if(Q_UNLIKELY(_self==NULL))
    {
        _self=new FileDownloader(parent);
    }
}

FileDownloader::FileDownloader(QObject *parent) : QLopService(parent)
{
    QNetworkProxyQuery q(QUrl("http://www.google.com"));
    q.setQueryType(QNetworkProxyQuery::UrlRequest);
    q.setProtocolTag("http");
    QList<QNetworkProxy> proxies = QNetworkProxyFactory::systemProxyForQuery(q);
    if( proxies.size() > 0 && proxies[0].type() != QNetworkProxy::NoProxy )
      QNetworkProxy::setApplicationProxy(proxies[0]);
    else
     qDebug("No proxy server selected");
    m_WebCtrl = new QNetworkAccessManager(this);
    m_pendingTasks = new QList<FileDownloaderTask*>();
    if(!m_noGui)
        m_gui=new DownLoadHistory();
}

FileDownloader::~FileDownloader()
{
    if(!m_noGui)
        delete m_gui;
    while (m_pendingTasks->count())
    {
        FileDownloaderTask* task=m_pendingTasks->last();
        m_pendingTasks->removeLast();
        delete task;
    }
    delete m_WebCtrl;
}