/*
    Copyright (c) 2006 - 2007 Volker Krause <vkrause@kde.org>

    This library is free software; you can redistribute it and/or modify it
    under the terms of the GNU Library General Public License as published by
    the Free Software Foundation; either version 2 of the License, or (at your
    option) any later version.

    This library 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 Library General Public
    License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to the
    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301, USA.
*/

#include "collectionview.h"

#include "collection.h"
#include "collectionmodel.h"
#include "control.h"

#include <kicon.h>
#include <kaction.h>
#include <kdebug.h>
#include <klocalizedstring.h>
#include <kmessagebox.h>
#include <kurl.h>
#include <kxmlguifactory.h>
#include <kxmlguiwindow.h>

#include <QtCore/QDebug>
#include <QtCore/QTimer>
#include <QApplication>
#include <QDragMoveEvent>
#include <QHeaderView>
#include <QMenu>

using namespace Akonadi;

/**
 * @internal
 */
class CollectionView::Private
{
public:
    Private(CollectionView *parent)
        : mParent(parent)
        , xmlGuiClient(0)
    {
    }

    void init();
    void dragExpand();
    void itemClicked(const QModelIndex &);
    void itemCurrentChanged(const QModelIndex &);
    bool hasParent(const QModelIndex &idx, Collection::Id parentId);

    CollectionView *mParent;
    QModelIndex dragOverIndex;
    QTimer dragExpandTimer;

    KXMLGUIClient *xmlGuiClient;
};

void CollectionView::Private::init()
{
    mParent->header()->setClickable(true);
    mParent->header()->setStretchLastSection(false);

    mParent->setSortingEnabled(true);
    mParent->sortByColumn(0, Qt::AscendingOrder);
    mParent->setEditTriggers(QAbstractItemView::EditKeyPressed);
    mParent->setAcceptDrops(true);
    mParent->setDropIndicatorShown(true);
    mParent->setDragDropMode(DragDrop);
    mParent->setDragEnabled(true);

    dragExpandTimer.setSingleShot(true);
    mParent->connect(&dragExpandTimer, SIGNAL(timeout()), SLOT(dragExpand()));

    mParent->connect(mParent, SIGNAL(clicked(QModelIndex)),
                     mParent, SLOT(itemClicked(QModelIndex)));

    Control::widgetNeedsAkonadi(mParent);
}

bool CollectionView::Private::hasParent(const QModelIndex &idx, Collection::Id parentId)
{
    QModelIndex idx2 = idx;
    while (idx2.isValid()) {
        if (mParent->model()->data(idx2, CollectionModel::CollectionIdRole).toLongLong() == parentId) {
            return true;
        }

        idx2 = idx2.parent();
    }
    return false;
}

void CollectionView::Private::dragExpand()
{
    mParent->setExpanded(dragOverIndex, true);
    dragOverIndex = QModelIndex();
}

void CollectionView::Private::itemClicked(const QModelIndex &index)
{
    if (!index.isValid()) {
        return;
    }

    const Collection collection = index.model()->data(index, CollectionModel::CollectionRole).value<Collection>();
    if (!collection.isValid()) {
        return;
    }

    emit mParent->clicked(collection);
}

void CollectionView::Private::itemCurrentChanged(const QModelIndex &index)
{
    if (!index.isValid()) {
        return;
    }

    const Collection collection = index.model()->data(index, CollectionModel::CollectionRole).value<Collection>();
    if (!collection.isValid()) {
        return;
    }

    emit mParent->currentChanged(collection);
}

CollectionView::CollectionView(QWidget *parent)
    : QTreeView(parent)
    , d(new Private(this))
{
    d->init();
}

CollectionView::CollectionView(KXMLGUIClient *xmlGuiClient, QWidget *parent)
    : QTreeView(parent)
    , d(new Private(this))
{
    d->xmlGuiClient = xmlGuiClient;
    d->init();
}

CollectionView::CollectionView(KXmlGuiWindow *xmlGuiWindow, QWidget *parent)
    : QTreeView(parent)
    , d(new Private(this))
{
    d->xmlGuiClient = static_cast<KXMLGUIClient *>(xmlGuiWindow);
    d->init();
}

CollectionView::~CollectionView()
{
    delete d;
}

void CollectionView::setModel(QAbstractItemModel *model)
{
    QTreeView::setModel(model);
    header()->setStretchLastSection(true);

    connect(selectionModel(), SIGNAL(currentChanged(QModelIndex,QModelIndex)),
            this, SLOT(itemCurrentChanged(QModelIndex)));
}

void CollectionView::dragMoveEvent(QDragMoveEvent *event)
{
    QModelIndex index = indexAt(event->pos());
    if (d->dragOverIndex != index) {
        d->dragExpandTimer.stop();
        if (index.isValid() && !isExpanded(index) && itemsExpandable()) {
            d->dragExpandTimer.start(QApplication::startDragTime());
            d->dragOverIndex = index;
        }
    }

    // Check if the collection under the cursor accepts this data type
    const QStringList supportedContentTypes = model()->data(index, CollectionModel::CollectionRole).value<Collection>().contentMimeTypes();
    const QMimeData *mimeData = event->mimeData();
    const KUrl::List urls = KUrl::List::fromMimeData(mimeData);
    foreach (const KUrl &url, urls) {

        const Collection collection = Collection::fromUrl(url);
        if (collection.isValid()) {
            if (!supportedContentTypes.contains(QString::fromLatin1("inode/directory"))) {
                break;
            }

            // Check if we don't try to drop on one of the children
            if (d->hasParent(index, collection.id())) {
                break;
            }
        } else {
            const QString type = url.queryItems()[QString::fromLatin1("type")];
            if (!supportedContentTypes.contains(type)) {
                break;
            }
        }

        QTreeView::dragMoveEvent(event);
        return;
    }

    event->setDropAction(Qt::IgnoreAction);
}

void CollectionView::dragLeaveEvent(QDragLeaveEvent *event)
{
    d->dragExpandTimer.stop();
    d->dragOverIndex = QModelIndex();
    QTreeView::dragLeaveEvent(event);
}

void CollectionView::dropEvent(QDropEvent *event)
{
    d->dragExpandTimer.stop();
    d->dragOverIndex = QModelIndex();

    // open a context menu offering different drop actions (move, copy and cancel)
    // TODO If possible, hide non available actions ...
    QMenu popup(this);
    QAction *moveDropAction = popup.addAction(KIcon(QString::fromLatin1("edit-rename")), i18n("&Move here"));
    QAction *copyDropAction = popup.addAction(KIcon(QString::fromLatin1("edit-copy")), i18n("&Copy here"));
    popup.addSeparator();
    popup.addAction(KIcon(QString::fromLatin1("process-stop")), i18n("Cancel"));

    QAction *activatedAction = popup.exec(QCursor::pos());
    if (activatedAction == moveDropAction) {
        event->setDropAction(Qt::MoveAction);
    } else if (activatedAction == copyDropAction) {
        event->setDropAction(Qt::CopyAction);
    } else {
        return;
    }

    QTreeView::dropEvent(event);
}

void CollectionView::contextMenuEvent(QContextMenuEvent *event)
{
    if (!d->xmlGuiClient) {
        return;
    }
    QMenu *popup = static_cast<QMenu *>(d->xmlGuiClient->factory()->container(
                                            QLatin1String("akonadi_collectionview_contextmenu"), d->xmlGuiClient));
    if (popup) {
        popup->exec(event->globalPos());
    }
}

void CollectionView::setXmlGuiClient(KXMLGUIClient *xmlGuiClient)
{
    d->xmlGuiClient = xmlGuiClient;
}

void CollectionView::setXmlGuiWindow(KXmlGuiWindow *xmlGuiWindow)
{
    d->xmlGuiClient = static_cast<KXMLGUIClient *>(xmlGuiWindow);
}

#include "moc_collectionview.cpp"