Support HTML5 <datalist> element

The datalist uses Chromium's autofill component to fetch and filter
predefined options in the list and autocomplete the field with the
selected option. Autofill component is added to build and bound to
WebEngine. All the unnecessary autofill features for datalist are
supposed to be disabled: payment/credit card support, password manager,
save profile data, store suggestions in database etc.

Custom popups for the dropdown are implemented for Widget and Quick.
Scrolling in dropdown is not implemented in this change.

Fixes: QTBUG-54433
Pick-to: 6.4
Change-Id: I155d02d6dbc9d88fbca4bc5f55b76c19d0ba7a9d
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

1 files changed, 150 insertions, 0 deletions

diff --git a/src/core/autofill_popup_controller.cpp b/src/core/autofill_popup_controller.cpp
new file mode 100644
index 000000000..e42f5a4f6
--- /dev/null
+++ b/src/core/autofill_popup_controller.cpp
@@ -0,0 +1,150 @@
+/****************************************************************************
+**
+** Copyright (C) 2022 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "autofill_popup_controller.h"
+#include "autofill_popup_controller_p.h"
+
+#include "components/autofill/core/browser/ui/autofill_popup_delegate.h"
+#include "components/autofill/core/browser/ui/suggestion.h"
+
+namespace QtWebEngineCore {
+
+AutofillPopupController::AutofillPopupController(AutofillPopupControllerPrivate *dd)
+{
+    Q_ASSERT(dd);
+    d.reset(dd);
+}
+
+AutofillPopupController::~AutofillPopupController() { }
+
+void AutofillPopupController::setCurrentIndex(const QModelIndex &index)
+{
+    if (m_currentIndex == index)
+        return;
+
+    m_currentIndex = index;
+
+    if (m_currentIndex.isValid()) {
+        const autofill::Suggestion &suggestion = d->suggestions[m_currentIndex.row()];
+        d->delegate->DidSelectSuggestion(suggestion.value, suggestion.frontend_id);
+    }
+
+    Q_EMIT currentIndexChanged(index);
+}
+
+void AutofillPopupController::selectPreviousSuggestion()
+{
+    if (!m_currentIndex.isValid()) {
+        setCurrentIndex(m_model.index(m_model.rowCount() - 1, 0));
+        return;
+    }
+
+    if (m_currentIndex.row() == 0) {
+        selectLastSuggestion();
+        return;
+    }
+
+    setCurrentIndex(m_model.index(m_currentIndex.row() - 1, 0));
+}
+
+void AutofillPopupController::selectNextSuggestion()
+{
+    if (!m_currentIndex.isValid()) {
+        setCurrentIndex(m_model.index(0, 0));
+        return;
+    }
+
+    if (m_currentIndex.row() == m_model.rowCount() - 1) {
+        selectFirstSuggestion();
+        return;
+    }
+
+    setCurrentIndex(m_model.index(m_currentIndex.row() + 1, 0));
+}
+
+void AutofillPopupController::selectFirstSuggestion()
+{
+    setCurrentIndex(m_model.index(0, 0));
+}
+
+void AutofillPopupController::selectLastSuggestion()
+{
+    setCurrentIndex(m_model.index(m_model.rowCount() - 1, 0));
+}
+
+void AutofillPopupController::acceptSuggestion()
+{
+    if (!m_currentIndex.isValid())
+        return;
+
+    const int index = m_currentIndex.row();
+    const autofill::Suggestion &suggestion = d->suggestions[index];
+    d->delegate->DidAcceptSuggestion(suggestion.value, suggestion.frontend_id,
+                                     suggestion.backend_id, index);
+}
+
+void AutofillPopupController::notifyPopupShown()
+{
+    d->delegate->OnPopupShown();
+}
+
+void AutofillPopupController::notifyPopupHidden()
+{
+    d->delegate->OnPopupHidden();
+}
+
+void AutofillPopupController::selectSuggestion(int index)
+{
+    if (index < 0)
+        setCurrentIndex(QModelIndex());
+    else
+        setCurrentIndex(m_model.index(index, 0));
+}
+
+void AutofillPopupController::updateModel()
+{
+    QStringList values;
+    for (size_t i = 0; i < d->suggestions.size(); ++i) {
+        values.append(QString::fromStdU16String(d->suggestions[i].value));
+    }
+    m_model.setStringList(values);
+    setCurrentIndex(QModelIndex());
+}
+
+} // namespace QtWebEngineCore