/***************************************************************************
*   Copyright (C) 2009 Matthias Fuchs <mat69@gmx.net>                     *
*                                                                         *
*   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 Street, Fifth Floor, Boston, MA  02110-1301  USA .        *
***************************************************************************/

#include "checksumsearch.h"

#include "core/verifier.h"

#include <QFile>
#include <QFileInfo>

#include <KDebug>
#include <KLocale>

const QStringList ChecksumSearch::URLCHANGEMODES = (QStringList() << i18n("Append") << i18n("Replace file") << i18n("Replace file-ending"));

ChecksumSearch::ChecksumSearch(const QList<KUrl> &srcs, const QString &fileName, const QStringList &types, QObject *parent)
  : QObject(parent),
    m_copyJob(0),
    m_srcs(srcs),
    m_fileName(fileName),
    m_types(types)
{
    createDownload();
}

ChecksumSearch::~ChecksumSearch()
{
    if (m_copyJob)
    {
        m_copyJob->kill(KJob::Quietly);
    }
}

void ChecksumSearch::createDownload()
{
    if (m_srcs.isEmpty() || m_types.isEmpty()) {
        deleteLater();
    } else {
        m_src = m_srcs.takeFirst();
        m_type = m_types.takeFirst();
        m_isEmpty = m_type.isEmpty();

        m_copyJob = KIO::get(m_src, KIO::Reload, KIO::HideProgressInfo);
        connect(m_copyJob, SIGNAL(data(KIO::Job*,QByteArray)), SLOT(slotData(KIO::Job*,QByteArray)));
        connect(m_copyJob, SIGNAL(result(KJob*)), SLOT(slotResult(KJob*)));
    }
}

void ChecksumSearch::slotData(KIO::Job *job, const QByteArray &data)
{
    Q_UNUSED(job)

    if (m_dataBA.size() > 5 * 1024) {
        m_copyJob->kill(KJob::EmitResult);
    } else {
        m_dataBA.append(data);
    }
}

void ChecksumSearch::slotResult(KJob *job)
{
    m_data.clear();

    switch (job->error())
    {
        case 0://The download has finished
        {
            kDebug() << "Correctly downloaded" << m_src.pathOrUrl();
            m_data = QString(m_dataBA);
            break;
        }

        default:
            kDebug() << "There was error" << job->error() << "while downloading" << m_src.pathOrUrl();
            break;
    }

    m_copyJob = 0;
    m_dataBA.clear();

    parseDownload();
}

void ChecksumSearch::parseDownload()
{
    if (!m_data.isEmpty()) {
        kDebug() << "*******Parse*******\n" << m_data << "*******************";
    }

    //no type has been specified
    if (m_type.isEmpty()) {
        parseDownloadEmpty();
        return;
    }

    const int length = Verifier::diggestLength(m_type);

    const QString patternChecksum = QString("\\w{%1}").arg(length);
    QRegExp rxChecksum(patternChecksum);
    QString hash;

    //find the correct line
    const QStringList lines = m_data.split('\n');
    foreach (const QString &line, lines) {
        if (line.contains(m_fileName, Qt::CaseInsensitive)) {
            if (rxChecksum.indexIn(line) > -1) {
                hash = rxChecksum.cap(0).toLower();
                if (!m_fileName.contains(hash, Qt::CaseInsensitive)) {
                    kDebug() << "Found hash: " << hash;
                    emit data(m_type, hash);
                }
            }
        }
    }

    //nothing found yet, so simply search for a word in the whole data that has the correct length
    if (hash.isEmpty() && (rxChecksum.indexIn(m_data) > -1)) {
        QString hash = rxChecksum.cap(0);
        if (!m_fileName.contains(hash, Qt::CaseInsensitive)) {
            kDebug() << "Found hash:" << hash;
            emit data(m_type, hash);
        }
    }

    //only create a download here if type was specified, otherwise parseDownloadEmpty has to handle this
    if (!m_isEmpty) {
        createDownload();
    }
}

void ChecksumSearch::parseDownloadEmpty()
{
    const QStringList lines = m_data.split('\n');
    const QStringList supportedTypes = Verifier::supportedVerficationTypes();
    foreach (const QString &type, supportedTypes)
    {
        if (m_data.contains(type, Qt::CaseInsensitive))
        {
            m_type = type;
            parseDownload();
        }
    }

    createDownload();
}

KUrl ChecksumSearch::createUrl(const KUrl &src, const QString &change, ChecksumSearch::UrlChangeMode mode)
{
    if (!src.isValid() || change.isEmpty())
    {
        return KUrl();
    }

    KUrl url;
    if (mode == kg_Append)
    {
        url = KUrl(src.pathOrUrl() + change);
    }
    else if (mode == kg_ReplaceFile)
    {
        KUrl temp = src.upUrl();
        temp.addPath(change);
        url = temp;
    }
    else if (mode == kg_ReplaceEnding)
    {
        QString fileName = src.fileName();

        int index = fileName.lastIndexOf('.');
        if (index > -1)
        {
            fileName = fileName.left(index);
            index = fileName.lastIndexOf('.');
            // FIXME: for anything other than *.tar.* this would be wrong as it could be version,
            // e.g. foo-1.2.3.gz. have to probe for two cases here
            if (index > -1)
            {
                fileName = fileName.left(index);
            }
        }
        KUrl temp = src.upUrl();
        temp.addPath(fileName + change);
        url = temp;
    }

    return url;
}

#include "moc_checksumsearch.cpp"