/* -*- mode: c++; c-basic-offset:4 -*-
    dialogs/certificateselectiondialog.cpp

    This file is part of Kleopatra, the KDE keymanager
    Copyright (c) 2008 Klarälvdalens Datakonsult AB

    Kleopatra 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.

    Kleopatra 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

    In addition, as a special exception, the copyright holders give
    permission to link the code of this program with any edition of
    the Qt library by Trolltech AS, Norway (or with modified versions
    of Qt that use the same license as Qt), and distribute linked
    combinations including the two.  You must obey the GNU General
    Public License in all respects for all of the code used other than
    Qt.  If you modify this file, you may extend this exception to
    your version of the file, but you are not obligated to do so.  If
    you do not wish to do so, delete this exception statement from
    your version.
*/

#include <config-kleopatra.h>

#include "certificateselectiondialog.h"

#include <view/searchbar.h>
#include <view/tabwidget.h>

#include <Libkleo/KeyListModel>
#include <Libkleo/KeyCache>

#include <commands/reloadkeyscommand.h>
#include <commands/lookupcertificatescommand.h>
#include <commands/newcertificatecommand.h>

#include <gpgme++/key.h>

#include <KLocalizedString>
#include <KConfigGroup>
#include <KSharedConfig>

#include <QLabel>
#include <QPushButton>
#include <QDialogButtonBox>
#include <QItemSelectionModel>
#include <QAbstractItemView>
#include <QPointer>
#include <QVBoxLayout>

#include <algorithm>
#include <cassert>

using namespace Kleo;
using namespace Kleo::Dialogs;
using namespace Kleo::Commands;
using namespace GpgME;

class CertificateSelectionDialog::Private
{
    friend class ::Kleo::Dialogs::CertificateSelectionDialog;
    CertificateSelectionDialog *const q;
public:
    explicit Private(CertificateSelectionDialog *qq);

private:
    void reload()
    {
        Command *const cmd = new ReloadKeysCommand(nullptr);
        cmd->setParentWidget(q);
        cmd->start();
    }
    void create()
    {
        NewCertificateCommand *cmd = new NewCertificateCommand(nullptr);
        cmd->setParentWidget(q);
        if ((options & AnyFormat) != AnyFormat) {
            cmd->setProtocol((options & OpenPGPFormat) ? OpenPGP : CMS);
        }
        cmd->start();
    }
    void lookup()
    {
        Command *const cmd = new LookupCertificatesCommand(nullptr);
        cmd->setParentWidget(q);
        cmd->start();
    }
    void slotKeysMayHaveChanged();
    void slotCurrentViewChanged(QAbstractItemView *newView);
    void slotSelectionChanged();
    void slotDoubleClicked(const QModelIndex &idx);

private:
    bool acceptable(const std::vector<Key> &keys)
    {
        return !keys.empty();
    }
    void updateLabelText()
    {
        ui.label.setText(!customLabelText.isEmpty() ? customLabelText :
                         (options & MultiSelection)
                         ? i18n("Please select one or more of the following certificates:")
                         : i18n("Please select one of the following certificates:"));
    }

private:
    QPointer<QAbstractItemView> lastView;
    QString customLabelText;
    Options options;

    struct UI {
        QLabel label;
        SearchBar searchBar;
        TabWidget tabWidget;
        QDialogButtonBox buttonBox;
        QVBoxLayout vlay;

        explicit UI(CertificateSelectionDialog *q)
            : label(q),
              searchBar(q),
              tabWidget(q),
              buttonBox(q),
              vlay(q)
        {
            KDAB_SET_OBJECT_NAME(label);
            KDAB_SET_OBJECT_NAME(searchBar);
            KDAB_SET_OBJECT_NAME(tabWidget);
            KDAB_SET_OBJECT_NAME(buttonBox);
            KDAB_SET_OBJECT_NAME(vlay);

            vlay.addWidget(&label);
            vlay.addWidget(&searchBar);
            vlay.addWidget(&tabWidget, 1);
            vlay.addWidget(&buttonBox);

            QPushButton *const ok = buttonBox.addButton(QDialogButtonBox::Ok);
            ok->setEnabled(false);
            QPushButton *const cancel = buttonBox.addButton(QDialogButtonBox::Close);
            Q_UNUSED(cancel);
            QPushButton *const reload = buttonBox.addButton(i18n("Reload"),    QDialogButtonBox::ActionRole);
            QPushButton *const lookup = buttonBox.addButton(i18n("Lookup..."), QDialogButtonBox::ActionRole);
            QPushButton *const create = buttonBox.addButton(i18n("New..."),    QDialogButtonBox::ActionRole);

            lookup->setToolTip(i18nc("@info:tooltip", "Lookup certificates on server"));
            reload->setToolTip(i18nc("@info:tooltip", "Refresh certificate list"));
            create->setToolTip(i18nc("@info:tooltip", "Create a new certificate"));

            connect(&buttonBox, &QDialogButtonBox::accepted, q, &CertificateSelectionDialog::accept);
            connect(&buttonBox, &QDialogButtonBox::rejected, q, &CertificateSelectionDialog::reject);
            connect(reload,     SIGNAL(clicked()),  q, SLOT(reload()));
            connect(lookup,     SIGNAL(clicked()),  q, SLOT(lookup()));
            connect(create,     SIGNAL(clicked()),  q, SLOT(create()));
            connect(KeyCache::instance().get(), SIGNAL(keysMayHaveChanged()),
                    q, SLOT(slotKeysMayHaveChanged()));
        }
    } ui;
};

CertificateSelectionDialog::Private::Private(CertificateSelectionDialog *qq)
    : q(qq),
      ui(q)
{
    ui.tabWidget.setFlatModel(AbstractKeyListModel::createFlatKeyListModel());
    ui.tabWidget.setHierarchicalModel(AbstractKeyListModel::createHierarchicalKeyListModel());
    ui.tabWidget.connectSearchBar(&ui.searchBar);

    connect(&ui.tabWidget, SIGNAL(currentViewChanged(QAbstractItemView*)),
            q, SLOT(slotCurrentViewChanged(QAbstractItemView*)));

    updateLabelText();
    q->setWindowTitle(i18n("Certificate Selection"));
}

CertificateSelectionDialog::CertificateSelectionDialog(QWidget *parent)
    : QDialog(parent), d(new Private(this))
{
    const KSharedConfig::Ptr config = KSharedConfig::openConfig(QStringLiteral("kleopatracertificateselectiondialogrc"));
    d->ui.tabWidget.loadViews(config.data());
    const KConfigGroup geometry(config, "Geometry");
    resize(geometry.readEntry("size", size()));
    d->slotKeysMayHaveChanged();
}

CertificateSelectionDialog::~CertificateSelectionDialog() {}

void CertificateSelectionDialog::setCustomLabelText(const QString &txt)
{
    if (txt == d->customLabelText) {
        return;
    }
    d->customLabelText = txt;
    d->updateLabelText();
}

QString CertificateSelectionDialog::customLabelText() const
{
    return d->customLabelText;
}

void CertificateSelectionDialog::setOptions(Options options)
{
    if (d->options == options) {
        return;
    }
    d->options = options;

    d->ui.tabWidget.setMultiSelection(options & MultiSelection);

    d->slotKeysMayHaveChanged();
}

CertificateSelectionDialog::Options CertificateSelectionDialog::options() const
{
    return d->options;
}

void CertificateSelectionDialog::setStringFilter(const QString &filter)
{
    d->ui.tabWidget.setStringFilter(filter);
}

void CertificateSelectionDialog::setKeyFilter(const std::shared_ptr<KeyFilter> &filter)
{
    d->ui.tabWidget.setKeyFilter(filter);
}

void CertificateSelectionDialog::selectCertificates(const std::vector<Key> &keys)
{
    const QAbstractItemView *const view = d->ui.tabWidget.currentView();
    if (!view) {
        return;
    }
    const auto *const model = d->ui.tabWidget.currentModel();
    assert(model);
    QItemSelectionModel *const sm = view->selectionModel();
    assert(sm);

    Q_FOREACH (const QModelIndex &idx, model->indexes(keys))
        if (idx.isValid()) {
            sm->select(idx, QItemSelectionModel::Select | QItemSelectionModel::Rows);
        }
}

void CertificateSelectionDialog::selectCertificate(const Key &key)
{
    selectCertificates(std::vector<Key>(1, key));
}

std::vector<Key> CertificateSelectionDialog::selectedCertificates() const
{
    const QAbstractItemView *const view = d->ui.tabWidget.currentView();
    if (!view) {
        return std::vector<Key>();
    }
    const auto *const model = d->ui.tabWidget.currentModel();
    assert(model);
    const QItemSelectionModel *const sm = view->selectionModel();
    assert(sm);
    return model->keys(sm->selectedRows());
}

Key CertificateSelectionDialog::selectedCertificate() const
{
    const std::vector<Key> keys = selectedCertificates();
    return keys.empty() ? Key() : keys.front();
}

void CertificateSelectionDialog::hideEvent(QHideEvent *e)
{
    KSharedConfig::Ptr config = KSharedConfig::openConfig(QStringLiteral("kleopatracertificateselectiondialogrc"));
    d->ui.tabWidget.saveViews(config.data());
    KConfigGroup geometry(config, "Geometry");
    geometry.writeEntry("size", size());
    QDialog::hideEvent(e);
}

void CertificateSelectionDialog::Private::slotKeysMayHaveChanged()
{
    q->setEnabled(true);
    std::vector<Key> keys = (options & SecretKeys) ? KeyCache::instance()->secretKeys() : KeyCache::instance()->keys();
    q->filterAllowedKeys(keys, options);
    const std::vector<Key> selected = q->selectedCertificates();
    if (AbstractKeyListModel *const model = ui.tabWidget.flatModel()) {
        model->setKeys(keys);
    }
    if (AbstractKeyListModel *const model = ui.tabWidget.hierarchicalModel()) {
        model->setKeys(keys);
    }
    q->selectCertificates(selected);
}

void CertificateSelectionDialog::filterAllowedKeys(std::vector<Key> &keys, int options)
{
    std::vector<Key>::iterator end = keys.end();

    switch (options & AnyFormat) {
    case OpenPGPFormat:
        end = std::remove_if(keys.begin(), end, [](const Key &key) { return key.protocol() != OpenPGP; });
        break;
    case CMSFormat:
        end = std::remove_if(keys.begin(), end, [](const Key &key) { return key.protocol() != CMS; });
        break;
    default:
    case AnyFormat:
        ;
    }

    switch (options & AnyCertificate) {
    case SignOnly:
        end = std::remove_if(keys.begin(), end, [](const Key &key) { return !key.canReallySign(); });
        break;
    case EncryptOnly:
        end = std::remove_if(keys.begin(), end, [](const Key &key) { return !key.canEncrypt(); });
        break;
    default:
    case AnyCertificate:
        ;
    }

    if (options & SecretKeys) {
        end = std::remove_if(keys.begin(), end, [](const Key &key) { return !key.hasSecret(); });
    }

    keys.erase(end, keys.end());
}

void CertificateSelectionDialog::Private::slotCurrentViewChanged(QAbstractItemView *newView)
{
    if (lastView) {
        disconnect(lastView, SIGNAL(doubleClicked(QModelIndex)),
                   q, SLOT(slotDoubleClicked(QModelIndex)));
        assert(lastView->selectionModel());
        disconnect(lastView->selectionModel(), SIGNAL(selectionChanged(QItemSelection,QItemSelection)),
                   q, SLOT(slotSelectionChanged()));
    }
    lastView = newView;
    if (newView) {
        connect(newView, SIGNAL(doubleClicked(QModelIndex)),
                q, SLOT(slotDoubleClicked(QModelIndex)));
        assert(newView->selectionModel());
        connect(newView->selectionModel(), SIGNAL(selectionChanged(QItemSelection,QItemSelection)),
                q, SLOT(slotSelectionChanged()));
    }
    slotSelectionChanged();
}

void CertificateSelectionDialog::Private::slotSelectionChanged()
{
    if (QPushButton *const pb = ui.buttonBox.button(QDialogButtonBox::Ok)) {
        pb->setEnabled(acceptable(q->selectedCertificates()));
    }
}

void CertificateSelectionDialog::Private::slotDoubleClicked(const QModelIndex &idx)
{
    QAbstractItemView *const view = ui.tabWidget.currentView();
    assert(view);
    const auto *const model = ui.tabWidget.currentModel();
    assert(model);
    Q_UNUSED(model);
    QItemSelectionModel *const sm = view->selectionModel();
    assert(sm);
    sm->select(idx, QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows);
    QMetaObject::invokeMethod(q, "accept", Qt::QueuedConnection);
}

void CertificateSelectionDialog::accept()
{
    if (d->acceptable(selectedCertificates())) {
        QDialog::accept();
    }
}

#include "moc_certificateselectiondialog.cpp"
