/*  -*- C++ -*-
 *  Copyright (C) 2003 Thiago Macieira <thiago@kde.org>
 *
 *
 *  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.
 */

#include "k3reverseresolver.h"

#include <config-network.h>

// System includes
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <signal.h>

// Qt
#include <QEvent>
#include <QMutex>
#include <QCoreApplication>

// Us
#include "k3resolver_p.h"
#include "k3resolverworkerbase.h"
#include "k3socketaddress.h"

#if !HAVE_GETNAMEINFO
// FIXME KDE4:
// move to syssocket or adapt
# include "netsupp.h"
#endif

using namespace KNetwork;
using namespace KNetwork::Internal;

namespace
{
class ReverseThread: public KResolverWorkerBase
{
public:
    ReverseThread(const KSocketAddress &addr, int flags)
        : m_addr(addr), m_flags(flags), m_parent(nullptr)
    { }

    virtual ~ReverseThread()
    { }

    bool preprocess() Q_DECL_OVERRIDE
    {
        return true;
    }
    bool run() Q_DECL_OVERRIDE;
    bool postprocess() Q_DECL_OVERRIDE;

    // input:
    KSocketAddress m_addr;
    int m_flags;
    KReverseResolver *m_parent;

    // output:
    QString node;
    QString service;
    bool success;
};

class KReverseResolverEvent: public QEvent
{
public:
    static const int myType = QEvent::User + 63; // arbitrary value
    QString node;
    QString service;
    bool success;

    KReverseResolverEvent(const QString &_node, const QString &_service,
                          bool _success)
        : QEvent((Type)myType), node(_node),
          service(_service), success(_success)
    { }
};
}

class KNetwork::KReverseResolverPrivate
{
public:
    QString node;
    QString service;
    KSocketAddress addr;
    int flags;

    ReverseThread *worker;
    bool success;

    inline KReverseResolverPrivate(const KSocketAddress &_addr)
        : addr(_addr), worker(nullptr), success(false)
    { }
};

KReverseResolver::KReverseResolver(const KSocketAddress &addr, int flags,
                                   QObject *parent)
    : QObject(parent), d(new KReverseResolverPrivate(addr))
{
    d->flags = flags;
}

KReverseResolver::~KReverseResolver()
{
    if (d->worker) {
        d->worker->m_parent = nullptr;
    }
    delete d;
}

bool KReverseResolver::isRunning() const
{
    return d->worker != nullptr;
}

bool KReverseResolver::success() const
{
    return !isRunning() && d->success;
}

bool KReverseResolver::failure() const
{
    return !isRunning() && !d->success;
}

QString KReverseResolver::node() const
{
    return d->node;
}

QString KReverseResolver::service() const
{
    return d->service;
}

const KSocketAddress &KReverseResolver::address() const
{
    return d->addr;
}

bool KReverseResolver::start()
{
    if (d->worker != nullptr) {
        return true;    // already started
    }

    d->worker = new ReverseThread(d->addr, d->flags);
    d->worker->m_parent = this;

    RequestData *req = new RequestData;
    req->obj = nullptr;
    req->input = nullptr;
    req->requestor = nullptr;
    req->worker = d->worker;
    KResolverManager::manager()->dispatch(req);
    return true;
}

bool KReverseResolver::event(QEvent *e)
{
    if (e->type() != KReverseResolverEvent::myType) {
        return QObject::event(e);    // call parent
    }

    KReverseResolverEvent *re = static_cast<KReverseResolverEvent *>(e);
    d->node = re->node;
    d->service = re->service;
    d->success = re->success;

    // don't delete d->worker!
    // KResolverManager::doNotifying takes care of that, if it hasn't already
    d->worker = nullptr;

    // emit signal
    emit finished(*this);

    return true;
}

bool KReverseResolver::resolve(const KSocketAddress &addr, QString &node,
                               QString &serv, int flags)
{
    ReverseThread th(addr, flags);
    if (th.run()) {
        node = th.node;
        serv = th.service;
        return true;
    }
    return false;
}

bool KReverseResolver::resolve(const struct sockaddr *sa, quint16 salen,
                               QString &node, QString &serv, int flags)
{
    return resolve(KSocketAddress(sa, salen), node, serv, flags);
}

bool ReverseThread::run()
{
    int err;
    char h[NI_MAXHOST], s[NI_MAXSERV];
    int niflags = 0;

    h[0] = s[0] = '\0';

    if (m_flags & KReverseResolver::NumericHost) {
        niflags |= NI_NUMERICHOST;
    }
    if (m_flags & KReverseResolver::NumericService) {
        niflags |= NI_NUMERICSERV;
    }
    if (m_flags & KReverseResolver::NodeNameOnly) {
        niflags |= NI_NOFQDN;
    }
    if (m_flags & KReverseResolver::Datagram) {
        niflags |= NI_DGRAM;
    }
    if (m_flags & KReverseResolver::ResolutionRequired) {
        niflags |= NI_NAMEREQD;
    }

    {
#ifdef NEED_MUTEX
        QMutexLocker locker(&::getXXbyYYmutex);
#endif
        err = ::getnameinfo(m_addr, m_addr.length(),
                            h, sizeof(h) - 1, s, sizeof(s) - 1, niflags);
    }

    if (err == 0) {
        node = KResolver::domainToUnicode(QLatin1String(h));
        service = QLatin1String(s);
        success = true;
    } else {
        node.clear(); service.clear();
        success = false;
    }

    return success;
}

bool ReverseThread::postprocess()
{
    // post an event
    if (m_parent)
        QCoreApplication::postEvent(m_parent,
                                    new KReverseResolverEvent(node, service, success));
    return true;
}

