File indexing completed on 2024-05-26 05:28:14

 /* Copyright (C) 2012 Thomas Gahr <thomas.gahr@physik.uni-muenchen.de>
    Copyright (C) 2006 - 2016 Jan Kundrát <jkt@kde.org>
 
    This file is part of the Trojita Qt IMAP e-mail client,
    http://trojita.flaska.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) version 3 or any later version
    accepted by the membership of KDE e.V. (or its successor approved
    by the membership of KDE e.V.), which shall act as a proxy
    defined in Section 14 of version 3 of the license.
 
    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, see <http://www.gnu.org/licenses/>.
 */
 
 #include <QDragMoveEvent>
 #include <QDropEvent>
 #include <QMenu>
 #include <QMimeData>
 #include "Common/SettingsNames.h"
 #include "Gui/MailBoxTreeView.h"
 #include "Gui/Util.h"
 #include "Imap/Model/ItemRoles.h"
 #include "Imap/Model/MailboxFinder.h"
 #include "Imap/Model/DragAndDrop.h"
 #include "UiUtils/IconLoader.h"
 
 namespace Gui {
 
 MailBoxTreeView::MailBoxTreeView(QWidget *parent, QSettings *settings)
     : QTreeView(parent)
     , m_mailboxFinder(nullptr), m_settings(settings)
 {
     setUniformRowHeights(true);
     setContextMenuPolicy(Qt::CustomContextMenu);
     setSelectionMode(QAbstractItemView::SingleSelection);
     setAllColumnsShowFocus(true);
     setAcceptDrops(true);
     setDropIndicatorShown(true);
     setHeaderHidden(true);
     // I wonder what's the best value to use here. Unfortunately, the default is to disable auto expanding.
     setAutoExpandDelay(800);
 
     // Track expansion/collapsing so that we remember this state despite the asynchronous nature of mailbox loading
     connect(this, &QTreeView::expanded, this, [this](const QModelIndex &what) {
         auto name = what.data(Imap::Mailbox::RoleMailboxName).toString();
         if (!m_desiredExpansionState.contains(name)) {
             m_desiredExpansionState.insert(name);
             emit mailboxExpansionChanged(m_desiredExpansionState.values());
         }
     });
     connect(this, &QTreeView::collapsed, this, [this](const QModelIndex &what) {
         auto name = what.data(Imap::Mailbox::RoleMailboxName).toString();
         if (m_desiredExpansionState.remove(name)) {
             emit mailboxExpansionChanged(m_desiredExpansionState.values());
         }
     });
 }
 
 /** \reimp
 
 The MailboxFinder has to be kept up-to-speed about these changes.
 */
 void MailBoxTreeView::setModel(QAbstractItemModel *model)
 {
     delete m_mailboxFinder;
     m_mailboxFinder = nullptr;
 
     if (model) {
         m_mailboxFinder = new Imap::Mailbox::MailboxFinder(this, model);
         connect(m_mailboxFinder, &Imap::Mailbox::MailboxFinder::mailboxFound,
                 this, [this](const QString &, const QModelIndex &index) {
             expand(index);
         });
         connect(model, &QAbstractItemModel::layoutChanged, this, &MailBoxTreeView::resetWatchedMailboxes);
         connect(model, &QAbstractItemModel::rowsRemoved, this, &MailBoxTreeView::resetWatchedMailboxes);
         connect(model, &QAbstractItemModel::modelReset, this, &MailBoxTreeView::resetWatchedMailboxes);
     }
     QTreeView::setModel(model);
     resetWatchedMailboxes();
 }
 /** @short Returns the user's default action from Qt::DropAction or Qt::IgnoreAction if not set */
 Qt::DropAction MailBoxTreeView::defaultDropAction()
 {
     auto mboxDropAction = m_settings->value(Common::SettingsNames::mboxDropAction, QVariant(QStringLiteral("ask"))).toString();
     if (mboxDropAction == QStringLiteral("move")) {
         return Qt::MoveAction;
     } else if (mboxDropAction == QStringLiteral("copy")) {
         return Qt::CopyAction;
     } else {
         return Qt::IgnoreAction;
     }
 }
 
 /** @short Reimplemented for more consistent handling of modifiers
 
   Qt's default behaviour is odd here:
   If you selected the move-action by pressing shift and you release the shift
   key while moving the mouse, the action does not change back to copy. But if you
   then move the mouse over a widget border - i.e. cause dragLeaveEvent, the action
   WILL change back to copy.
   This implementation immitates KDE's behaviour: react to a change in modifiers
   immediately.
 */
 void MailBoxTreeView::dragMoveEvent(QDragMoveEvent *event)
 {
     QTreeView::dragMoveEvent(event);
     if (!event->isAccepted())
         return;
     if (event->keyboardModifiers() == Qt::ShiftModifier)
         event->setDropAction(Qt::MoveAction);
     else
         event->setDropAction(Qt::CopyAction);
 }
 
 /** @short Reimplemented to present the user with a menu to choose between copy or move.
 
   Does not show the menu if either ctrl (copy messages) or shift (move messages)
   is pressed
 */
 void MailBoxTreeView::dropEvent(QDropEvent *event)
 {
     if (Gui::Util::isFromDistinctImapAccount(event)) {
         event->ignore();
         return;
     }
     if (event->keyboardModifiers() == Qt::ControlModifier) {
         event->setDropAction(Qt::CopyAction);
     } else if (event->keyboardModifiers() == Qt::ShiftModifier) {
         event->setDropAction(Qt::MoveAction);
     } else if (defaultDropAction() != Qt::IgnoreAction) {
         event->setDropAction(defaultDropAction());
     } else {
         QMenu menu(this);
         QAction *moveAction = menu.addAction(UiUtils::loadIcon(QStringLiteral("go-jump")), tr("Move here\tShift"));
         menu.addAction(UiUtils::loadIcon(QStringLiteral("edit-copy")), tr("Copy here\tCtrl"));
         QAction *cancelAction = menu.addAction(UiUtils::loadIcon(QStringLiteral("process-stop")), tr("Cancel"));
 
         QAction *selectedAction = menu.exec(mapToGlobal(event->pos()));
 
         // if user closes the menu or selects cancel, ignore the event
         if (!selectedAction || selectedAction == cancelAction) {
             event->ignore();
             return;
         }
 
         event->setDropAction(selectedAction == moveAction ? Qt::MoveAction : Qt::CopyAction);
     }
 
     QTreeView::dropEvent(event);
 }
 
 void MailBoxTreeView::dragEnterEvent(QDragEnterEvent *event)
 {
     if (Gui::Util::isFromDistinctImapAccount(event)) {
         event->ignore();
         return;
     }
     QTreeView::dragEnterEvent(event);
 }
 
 /** @short Specify which mailboxes should be expanded
 
 The mailboxes might appear and disappear at any time, so let's make sure that
 they are properly expanded/collapsed once they pop in.
 */
 void MailBoxTreeView::setDesiredExpansion(const QStringList &mailboxNames)
 {
     m_desiredExpansionState = QSet<QString>(mailboxNames.begin(), mailboxNames.end());
     resetWatchedMailboxes();
 }
 
 /** @short Ensure that we watch stuff that we need to watch */
 void MailBoxTreeView::resetWatchedMailboxes()
 {
     if (m_mailboxFinder) {
         for (const auto &mailbox: m_desiredExpansionState) {
             m_mailboxFinder->addMailbox(mailbox);
         }
     }
 }
 
 }