/*
    Copyright (c) 2009 Kevin Ottens <ervin@kde.org>

    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 "widget.h"

#include <akonadi/collection.h>
#include <akonadi/item.h>
#include <akonadi/itemcopyjob.h>
#include <akonadi/itemmovejob.h>

#include "storagemodel.h"
#include "core/messageitem.h"
#include "core/view.h"
#include <core/settings.h>

#include <QtCore/QTimer>
#include <QAction>
#include <QApplication>
#include <QDrag>
#include <QDragMoveEvent>
#include <QDropEvent>

#include <KDE/KActionCollection>
#include <KDE/KComboBox>
#include <KDE/KDebug>
#include <KDE/KIcon>
#include <KDE/KIconLoader>
#include <KDE/KLocale>
#include <KDE/KMenu>
#include <KDE/KToggleAction>
#include <KDE/KXMLGUIClient>
#include <KDE/KXMLGUIFactory>

#include "core/groupheaderitem.h"

#include <Akonadi/Monitor>
#include <Akonadi/Tag>
#include <Akonadi/TagFetchJob>
#include <Akonadi/TagFetchScope>
#include <Akonadi/TagAttribute>


namespace MessageList
{

class Widget::Private
{
public:
    Private( Widget *owner )
        : q( owner ), mLastSelectedMessage(-1), mXmlGuiClient( 0 ), mMonitor( 0 ) { }

    Akonadi::Item::List selectionAsItems() const;
    Akonadi::Item itemForRow( int row ) const;
    KMime::Message::Ptr messageForRow( int row ) const;

    Widget * const q;

    int mLastSelectedMessage;
    KXMLGUIClient *mXmlGuiClient;
    QModelIndex mGroupHeaderItemIndex;
    Akonadi::Monitor *mMonitor;
};

} // namespace MessageList

using namespace MessageList;
using namespace Akonadi;

Widget::Widget( QWidget *parent )
    : Core::Widget( parent ), d( new Private( this ) )
{
    populateStatusFilterCombo();

    d->mMonitor = new Akonadi::Monitor( this );
    d->mMonitor->setTypeMonitored( Akonadi::Monitor::Tags );
    connect(d->mMonitor, SIGNAL(tagAdded(Akonadi::Tag)), this, SLOT(populateStatusFilterCombo()));
    connect(d->mMonitor, SIGNAL(tagRemoved(Akonadi::Tag)), this, SLOT(populateStatusFilterCombo()));
    connect(d->mMonitor, SIGNAL(tagChanged(Akonadi::Tag)), this, SLOT(populateStatusFilterCombo()));
}

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

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

bool Widget::canAcceptDrag( const QDropEvent * e )
{
    if ( e->source() == view()->viewport() )
        return false;

    Collection::List collections = static_cast<const StorageModel*>( storageModel() )->displayedCollections();
    if ( collections.size()!=1 )
        return false; // no folder here or too many (in case we can't decide where the drop will end)

    const Collection target = collections.first();

    if ( ( target.rights() & Collection::CanCreateItem ) == 0 )
        return false; // no way to drag into

    const KUrl::List urls = KUrl::List::fromMimeData( e->mimeData() );
    foreach ( const KUrl &url, urls ) {
        const Collection collection = Collection::fromUrl( url );
        if ( collection.isValid() ) { // You're not supposed to drop collections here
            return false;
        } else { // Yay, this is an item!
            const QString type = url.queryItems()[QLatin1String( "type" )]; // But does it have the right type?
            if ( !target.contentMimeTypes().contains( type ) ) {
                return false;
            }
        }
    }

    return true;
}

bool Widget::selectNextMessageItem( MessageList::Core::MessageTypeFilter messageTypeFilter,
                                    MessageList::Core::ExistingSelectionBehaviour existingSelectionBehaviour,
                                    bool centerItem,
                                    bool loop )
{
    return view()->selectNextMessageItem( messageTypeFilter, existingSelectionBehaviour, centerItem, loop );
}

bool Widget::selectPreviousMessageItem( MessageList::Core::MessageTypeFilter messageTypeFilter,
                                        MessageList::Core::ExistingSelectionBehaviour existingSelectionBehaviour,
                                        bool centerItem,
                                        bool loop )
{
    return view()->selectPreviousMessageItem( messageTypeFilter, existingSelectionBehaviour, centerItem, loop );
}

bool Widget::focusNextMessageItem( MessageList::Core::MessageTypeFilter messageTypeFilter, bool centerItem, bool loop )
{
    return view()->focusNextMessageItem( messageTypeFilter, centerItem, loop );
}

bool Widget::focusPreviousMessageItem( MessageList::Core::MessageTypeFilter messageTypeFilter, bool centerItem, bool loop )
{
    return view()->focusPreviousMessageItem( messageTypeFilter, centerItem, loop );
}

void Widget::selectFocusedMessageItem( bool centerItem )
{
    view()->selectFocusedMessageItem( centerItem );
}

bool Widget::selectFirstMessageItem( MessageList::Core::MessageTypeFilter messageTypeFilter, bool centerItem )
{
    return view()->selectFirstMessageItem( messageTypeFilter, centerItem );
}

bool Widget::selectLastMessageItem( Core::MessageTypeFilter messageTypeFilter, bool centerItem )
{
    return view()->selectLastMessageItem( messageTypeFilter, centerItem );
}

void Widget::selectAll()
{
    view()->setAllGroupsExpanded( true );
    view()->selectAll();
}

void Widget::setCurrentThreadExpanded( bool expand )
{
    view()->setCurrentThreadExpanded(expand );
}

void Widget::setAllThreadsExpanded( bool expand )
{
    view()->setAllThreadsExpanded( expand );
}

void Widget::setAllGroupsExpanded( bool expand )
{
    view()->setAllGroupsExpanded(expand);
}

void Widget::focusQuickSearch(const QString &selectedText)
{
    view()->focusQuickSearch(selectedText);
}

void Widget::setQuickSearchClickMessage(const QString &msg)
{
    view()->setQuickSearchClickMessage(msg);
}

void Widget::fillMessageTagCombo()
{
    Akonadi::TagFetchJob *fetchJob = new Akonadi::TagFetchJob(this);
    fetchJob->fetchScope().fetchAttribute<Akonadi::TagAttribute>();
    connect(fetchJob, SIGNAL(result(KJob*)), this, SLOT(slotTagsFetched(KJob*)));
}

void Widget::slotTagsFetched(KJob *job)
{
    if (job->error()) {
        kWarning() << "Failed to load tags " << job->errorString();
        return;
    }
    Akonadi::TagFetchJob *fetchJob = static_cast<Akonadi::TagFetchJob*>(job);

    KConfigGroup conf( MessageList::Core::Settings::self()->config(),"MessageListView");
    const QString tagSelected= conf.readEntry(QLatin1String("TagSelected"));
    if(tagSelected.isEmpty()) {
        setCurrentStatusFilterItem();
        return;
    }
    const QStringList tagSelectedLst = tagSelected.split(QLatin1Char(','));

    addMessageTagItem( SmallIcon( QLatin1String( "mail-flag" ) ), i18n( "All" ), QString() );

    QStringList tagFound;
    foreach( const Akonadi::Tag &akonadiTag, fetchJob->tags() ) {
        if(tagSelectedLst.contains(akonadiTag.url().url())) {
            tagFound.append(akonadiTag.url().url());
            QString iconName = QLatin1String( "mail-tagged" );
            const QString label = akonadiTag.name();
            const QString id = akonadiTag.url().url();
            Akonadi::TagAttribute *attr = akonadiTag.attribute<Akonadi::TagAttribute>();
            if (attr) {
                iconName = attr->iconName();
            }
            addMessageTagItem( SmallIcon( iconName ), label, QVariant( id ) );
        }
    }
    conf.writeEntry(QLatin1String("TagSelected"), tagFound);
    conf.sync();

    setCurrentStatusFilterItem();
}

void Widget::viewMessageSelected( MessageList::Core::MessageItem *msg )
{
    int row = -1;
    if ( msg ) {
        row = msg->currentModelIndexRow();
    }

    if ( !msg || !msg->isValid() || !storageModel() ) {
        d->mLastSelectedMessage = -1;
        emit messageSelected( Item() );
        return;
    }

    Q_ASSERT( row >= 0 );

    d->mLastSelectedMessage = row;

    emit messageSelected( d->itemForRow( row ) ); // this MAY be null
}

void Widget::viewMessageActivated( MessageList::Core::MessageItem *msg )
{
    Q_ASSERT( msg ); // must not be null
    Q_ASSERT( storageModel() );

    if ( !msg->isValid() ) {
        return;
    }

    int row = msg->currentModelIndexRow();
    Q_ASSERT( row >= 0 );

    // The assert below may fail when quickly opening and closing a non-selected thread.
    // This will actually activate the item without selecting it...
    //Q_ASSERT( d->mLastSelectedMessage == row );

    if ( d->mLastSelectedMessage != row ) {
        // Very ugly. We are activating a non selected message.
        // This is very likely a double click on the plus sign near a thread leader.
        // Dealing with mLastSelectedMessage here would be expensive: it would involve releasing the last selected,
        // emitting signals, handling recursion... ugly.
        // We choose a very simple solution: double clicking on the plus sign near a thread leader does
        // NOT activate the message (i.e open it in a toplevel window) if it isn't previously selected.
        return;
    }

    emit messageActivated( d->itemForRow( row ) ); // this MAY be null
}

void Widget::viewSelectionChanged()
{
    emit selectionChanged();
    if ( !currentMessageItem() ) {
        emit messageSelected( Item() );
    }
}

void Widget::viewMessageListContextPopupRequest( const QList< MessageList::Core::MessageItem * > &selectedItems,
                                                 const QPoint &globalPos )
{
    Q_UNUSED( selectedItems );

    if ( !d->mXmlGuiClient )
        return;

    QMenu *popup = static_cast<QMenu*>( d->mXmlGuiClient->factory()->container(
                                            QLatin1String( "akonadi_messagelist_contextmenu" ),
                                            d->mXmlGuiClient ) );
    if ( popup ) {
        popup->exec( globalPos );
    }
}

void Widget::viewMessageStatusChangeRequest( MessageList::Core::MessageItem *msg, const Akonadi::MessageStatus &set, const Akonadi::MessageStatus &clear )
{
    Q_ASSERT( msg ); // must not be null
    Q_ASSERT( storageModel() );

    if ( !msg->isValid() ) {
        return;
    }

    int row = msg->currentModelIndexRow();
    Q_ASSERT( row >= 0 );

    Item item = d->itemForRow( row );
    Q_ASSERT( item.isValid() );

    emit messageStatusChangeRequest( item, set, clear );
}

void Widget::viewGroupHeaderContextPopupRequest( MessageList::Core::GroupHeaderItem *ghi, const QPoint &globalPos )
{
    Q_UNUSED( ghi );

    KMenu menu( this );

    QAction *act;

    QModelIndex index = view()->model()->index( ghi, 0 );
    d->mGroupHeaderItemIndex = index;

    if ( view()->isExpanded( index ) ) {
        act = menu.addAction( i18n ( "Collapse Group" ) );
        connect( act, SIGNAL(triggered(bool)),
                 this, SLOT(slotCollapseItem()) );
    } else {
        act = menu.addAction( i18n ( "Expand Group" ) );
        connect( act, SIGNAL(triggered(bool)),
                 this, SLOT(slotExpandItem()) );
    }

    menu.addSeparator();

    act = menu.addAction( i18n( "Expand All Groups" ) );
    connect( act, SIGNAL(triggered(bool)),
             view(), SLOT(slotExpandAllGroups()) );

    act = menu.addAction( i18n( "Collapse All Groups" ) );
    connect( act, SIGNAL(triggered(bool)),
             view(), SLOT(slotCollapseAllGroups()) );

    menu.exec( globalPos );
}

void Widget::viewDragEnterEvent( QDragEnterEvent *e )
{
    if ( !canAcceptDrag( e ) ) {
        e->ignore();
        return;
    }

    e->accept();
}

void Widget::viewDragMoveEvent( QDragMoveEvent *e )
{
    if ( !canAcceptDrag( e ) ) {
        e->ignore();
        return;
    }

    e->accept();
}

enum DragMode
{
    DragCopy,
    DragMove,
    DragCancel
};

void Widget::viewDropEvent( QDropEvent *e )
{
    if ( !canAcceptDrag( e ) ) {
        e->ignore();
        return;
    }

    KUrl::List urls = KUrl::List::fromMimeData( e->mimeData() );
    if ( urls.isEmpty() ) {
        kWarning() << "Could not decode drag data!";
        e->ignore();
        return;
    }

    e->accept();

    int action;
    if ( ( e->possibleActions() & Qt::MoveAction ) == 0 ) { // We can't move anyway
        action = DragCopy;
    } else {
        action = DragCancel;
        int keybstate = QApplication::keyboardModifiers();
        if ( keybstate & Qt::CTRL ) {
            action = DragCopy;

        } else if ( keybstate & Qt::SHIFT ) {
            action = DragMove;

        } else {
            KMenu menu;
            QAction *moveAction = menu.addAction( KIcon( QLatin1String( "go-jump" )), i18n( "&Move Here" ) );
            QAction *copyAction = menu.addAction( KIcon( QLatin1String( "edit-copy" ) ), i18n( "&Copy Here" ) );
            menu.addSeparator();
            menu.addAction( KIcon( QLatin1String( "dialog-cancel" ) ), i18n( "C&ancel" ) );

            QAction *menuChoice = menu.exec( QCursor::pos() );
            if ( menuChoice == moveAction ) {
                action = DragMove;
            } else if ( menuChoice == copyAction ) {
                action = DragCopy;
            } else {
                action = DragCancel;
            }
        }
    }
    if ( action == DragCancel )
        return;

    Collection::List collections = static_cast<const StorageModel*>( storageModel() )->displayedCollections();
    Collection target = collections.first();
    Item::List items;
    foreach ( const KUrl &url, urls ) {
        items << Item::fromUrl( url );
    }

    if ( action == DragCopy ) {
        new ItemCopyJob( items, target, this );
    } else if ( action == DragMove ) {
        new ItemMoveJob( items, target, this );
    }
}


void Widget::viewStartDragRequest()
{
    Collection::List collections = static_cast<const StorageModel*>( storageModel() )->displayedCollections();

    if ( collections.isEmpty() )
        return; // no folder here

    QList<Core::MessageItem *> selection = view()->selectionAsMessageItemList();
    if ( selection.isEmpty() ) {
        return;
    }

    bool readOnly = false;

    foreach ( const Collection &c, collections ) {
        // We won't be able to remove items from this collection
        if ( ( c.rights() & Collection::CanDeleteItem ) == 0 ) {
            // So the drag will be read-only
            readOnly = true;
            break;
        }
    }

    KUrl::List urls;
    Q_FOREACH ( Core::MessageItem *mi, selection ) {
        const Item i = d->itemForRow( mi->currentModelIndexRow() );
        KUrl url = i.url( Item::Item::Item::UrlWithMimeType );
        url.addQueryItem(QLatin1String("parent"), QString::number( mi->parentCollectionId() ) );
        urls << url;
    }

    QMimeData *mimeData = new QMimeData;
    urls.populateMimeData( mimeData );

    QDrag *drag = new QDrag( view()->viewport() );
    drag->setMimeData( mimeData );

    // Set pixmap
    QPixmap pixmap;
    if( selection.size() == 1 ) {
        pixmap = QPixmap( DesktopIcon(QLatin1String( "mail-message" ), KIconLoader::SizeSmall) );
    } else {
        pixmap = QPixmap( DesktopIcon(QLatin1String( "document-multiple" ), KIconLoader::SizeSmall) );
    }

    // Calculate hotspot (as in Konqueror)
    if( !pixmap.isNull() ) {
        drag->setHotSpot( QPoint( pixmap.width() / 2, pixmap.height() / 2 ) );
        drag->setPixmap( pixmap );
    }

    if ( readOnly )
        drag->exec( Qt::CopyAction );
    else
        drag->exec( Qt::CopyAction | Qt::MoveAction );
}

Item::List Widget::Private::selectionAsItems() const
{
    Item::List res;
    QList<Core::MessageItem *> selection = q->view()->selectionAsMessageItemList();

    foreach ( Core::MessageItem *mi, selection ) {
        Item i = itemForRow( mi->currentModelIndexRow() );
        Q_ASSERT( i.isValid() );
        res << i;
    }

    return res;
}

Item Widget::Private::itemForRow( int row ) const
{
    return static_cast<const StorageModel*>( q->storageModel() )->itemForRow( row );
}

KMime::Message::Ptr Widget::Private::messageForRow( int row ) const
{
    return static_cast<const StorageModel*>( q->storageModel() )->messageForRow( row );
}

Item Widget::currentItem() const
{
    Core::MessageItem *mi = view()->currentMessageItem();

    if ( mi == 0 ) {
        return Item();
    }

    return d->itemForRow( mi->currentModelIndexRow() );
}

KMime::Message::Ptr Widget::currentMessage() const
{
    Core::MessageItem *mi = view()->currentMessageItem();

    if ( mi == 0 ) {
        return KMime::Message::Ptr();
    }

    return d->messageForRow( mi->currentModelIndexRow() );
}


QList<KMime::Message::Ptr > Widget::selectionAsMessageList( bool includeCollapsedChildren ) const
{
    QList<KMime::Message::Ptr> lstMiPtr;
    QList<Core::MessageItem *> lstMi = view()->selectionAsMessageItemList( includeCollapsedChildren );
    if ( lstMi.isEmpty() ) {
        return lstMiPtr;
    }
    foreach( Core::MessageItem *it, lstMi ) {
        lstMiPtr.append( d->messageForRow( it->currentModelIndexRow() ) );
    }
    return lstMiPtr;
}

QList<Akonadi::Item> Widget::selectionAsMessageItemList( bool includeCollapsedChildren ) const
{
    QList<Item> lstMiPtr;
    QList<Core::MessageItem *> lstMi = view()->selectionAsMessageItemList( includeCollapsedChildren );
    if ( lstMi.isEmpty() ) {
        return lstMiPtr;
    }
    foreach( Core::MessageItem *it, lstMi ) {
        lstMiPtr.append( d->itemForRow( it->currentModelIndexRow() ) );
    }
    return lstMiPtr;
}

QVector<qlonglong> Widget::selectionAsMessageItemListId( bool includeCollapsedChildren ) const
{
    QVector<qlonglong> lstMiPtr;
    QList<Core::MessageItem *> lstMi = view()->selectionAsMessageItemList( includeCollapsedChildren );
    if ( lstMi.isEmpty() ) {
        return lstMiPtr;
    }
    foreach( Core::MessageItem *it, lstMi ) {
        lstMiPtr.append( d->itemForRow( it->currentModelIndexRow() ).id() );
    }
    return lstMiPtr;
}


QList<Akonadi::Item::Id> Widget::selectionAsListMessageId( bool includeCollapsedChildren ) const
{
    QList<qlonglong> lstMiPtr;
    QList<Core::MessageItem *> lstMi = view()->selectionAsMessageItemList( includeCollapsedChildren );
    if ( lstMi.isEmpty() ) {
        return lstMiPtr;
    }
    foreach( Core::MessageItem *it, lstMi ) {
        lstMiPtr.append( d->itemForRow( it->currentModelIndexRow() ).id() );
    }
    return lstMiPtr;
}

QList<Akonadi::Item> Widget::currentThreadAsMessageList() const
{
    QList<Item> lstMiPtr;
    QList<Core::MessageItem *> lstMi = view()->currentThreadAsMessageItemList();
    if ( lstMi.isEmpty() ) {
        return lstMiPtr;
    }
    foreach( Core::MessageItem *it, lstMi ) {
        lstMiPtr.append( d->itemForRow( it->currentModelIndexRow() ) );
    }
    return lstMiPtr;
}


QList<Akonadi::MessageStatus> Widget::currentFilterStatus() const
{
    return view()->currentFilterStatus();
}

QString Widget::currentFilterSearchString() const
{
    return view()->currentFilterSearchString();
}


bool Widget::isThreaded() const
{
    return view()->isThreaded();
}

bool Widget::selectionEmpty() const
{
    return view()->selectionEmpty();
}

bool Widget::getSelectionStats(
        Akonadi::Item::List &selectedItems,
        Akonadi::Item::List &selectedVisibleItems,
        bool * allSelectedBelongToSameThread,
        bool includeCollapsedChildren ) const
{
    if ( !storageModel() )
        return false;

    selectedItems.clear();
    selectedVisibleItems.clear();

    QList< Core::MessageItem * > selected = view()->selectionAsMessageItemList( includeCollapsedChildren );

    Core::MessageItem * topmost = 0;

    *allSelectedBelongToSameThread = true;

    foreach( Core::MessageItem *it, selected ) {
        const Item item = d->itemForRow( it->currentModelIndexRow() );
        selectedItems.append( item );
        if ( view()->isDisplayedWithParentsExpanded( it ) )
            selectedVisibleItems.append( item );
        if ( topmost == 0 )
            topmost = ( *it ).topmostMessage();
        else {
            if ( topmost != ( *it ).topmostMessage() )
                *allSelectedBelongToSameThread = false;
        }
    }
    return true;
}

void Widget::deletePersistentSet( MessageList::Core::MessageItemSetReference ref )
{
    view()->deletePersistentSet( ref );
}

void Widget::markMessageItemsAsAboutToBeRemoved( MessageList::Core::MessageItemSetReference ref, bool bMark )
{
    QList< Core::MessageItem * > lstPersistent = view()->persistentSetCurrentMessageItemList( ref );
    if ( !lstPersistent.isEmpty() )
        view()->markMessageItemsAsAboutToBeRemoved( lstPersistent, bMark );
}

QList<Akonadi::Item> Widget::itemListFromPersistentSet( MessageList::Core::MessageItemSetReference ref )
{
    QList<Akonadi::Item> lstItem;
    QList< Core::MessageItem * > refList = view()->persistentSetCurrentMessageItemList( ref );
    if ( !refList.isEmpty() ) {
        foreach( Core::MessageItem *it, refList ) {
            lstItem.append( d->itemForRow( it->currentModelIndexRow() ) );
        }
    }
    return lstItem;
}


MessageList::Core::MessageItemSetReference Widget::selectionAsPersistentSet( bool includeCollapsedChildren ) const
{
    QList<Core::MessageItem *> lstMi = view()->selectionAsMessageItemList( includeCollapsedChildren );
    if ( lstMi.isEmpty() ) {
        return -1;
    }
    return view()->createPersistentSet( lstMi );
}

MessageList::Core::MessageItemSetReference Widget::currentThreadAsPersistentSet() const
{
    QList<Core::MessageItem *> lstMi = view()->currentThreadAsMessageItemList();
    if ( lstMi.isEmpty() ) {
        return -1;
    }
    return view()->createPersistentSet( lstMi );
}

Akonadi::Collection Widget::currentCollection() const
{
    Collection::List collections = static_cast<const StorageModel*>( storageModel() )->displayedCollections();
    if ( collections.size()!=1 )
        return Akonadi::Collection(); // no folder here or too many (in case we can't decide where the drop will end)
    return collections.first();
}

void Widget::slotCollapseItem()
{
    view()->setCollapseItem(d->mGroupHeaderItemIndex);
}

void Widget::slotExpandItem()
{
    view()->setExpandItem(d->mGroupHeaderItemIndex);
}