Add QPdfPageNavigation class

The QPdfPageNavigation class encapsulates the logic of navigating
inside a QPdfDocument. It has the notion of a 'current' page and
provides slots to navigate to the previous/next page or jump
directly to a given page.
Additionally it provides properties to indicate whether there is
a previous or next page, relative to the current one.

Change-Id: I053f3c49ab4a70b2610b64d96d2c274c3d0f629b
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>

4 files changed, 209 insertions, 1 deletions

diff --git a/tests/auto/pdf/pdf.pro b/tests/auto/pdf/pdf.pro
index 04e36b3dc..388b8853d 100644
--- a/tests/auto/pdf/pdf.pro
+++ b/tests/auto/pdf/pdf.pro
@@ -1,4 +1,7 @@
 TEMPLATE = subdirs
 
-SUBDIRS = qpdfbookmarkmodel
+SUBDIRS = \
+    qpdfbookmarkmodel \
+    qpdfpagenavigation
+
 qtHaveModule(printsupport): SUBDIRS += qpdfdocument
diff --git a/tests/auto/pdf/qpdfpagenavigation/pdf-sample.pagenavigation.pdf b/tests/auto/pdf/qpdfpagenavigation/pdf-sample.pagenavigation.pdf
new file mode 100644
index 000000000..c4e1aa36e
--- /dev/null
+++ b/tests/auto/pdf/qpdfpagenavigation/pdf-sample.pagenavigation.pdf
diff --git a/tests/auto/pdf/qpdfpagenavigation/qpdfpagenavigation.pro b/tests/auto/pdf/qpdfpagenavigation/qpdfpagenavigation.pro
new file mode 100644
index 000000000..8de99543f
--- /dev/null
+++ b/tests/auto/pdf/qpdfpagenavigation/qpdfpagenavigation.pro
@@ -0,0 +1,5 @@
+CONFIG += testcase
+TARGET = tst_qpdfpagenavigation
+QT += pdf testlib network
+macos:CONFIG -= app_bundle
+SOURCES += tst_qpdfpagenavigation.cpp
diff --git a/tests/auto/pdf/qpdfpagenavigation/tst_qpdfpagenavigation.cpp b/tests/auto/pdf/qpdfpagenavigation/tst_qpdfpagenavigation.cpp
new file mode 100644
index 000000000..ff6a02750
--- /dev/null
+++ b/tests/auto/pdf/qpdfpagenavigation/tst_qpdfpagenavigation.cpp
@@ -0,0 +1,200 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://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.LGPLv3 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.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 later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+
+#include <QtTest/QtTest>
+
+#include <QPdfDocument>
+#include <QPdfPageNavigation>
+
+class tst_QPdfPageNavigation: public QObject
+{
+    Q_OBJECT
+
+private slots:
+    void defaultValues();
+    void setEmptyDocument();
+    void setEmptyDocumentAndLoad();
+    void setLoadedDocument();
+    void unloadDocument();
+    void navigate();
+};
+
+void tst_QPdfPageNavigation::defaultValues()
+{
+    QPdfPageNavigation pageNavigation;
+
+    QCOMPARE(pageNavigation.document(), nullptr);
+    QCOMPARE(pageNavigation.currentPage(), 0);
+    QCOMPARE(pageNavigation.pageCount(), 0);
+    QCOMPARE(pageNavigation.canGoToPreviousPage(), false);
+    QCOMPARE(pageNavigation.canGoToNextPage(), false);
+}
+
+void tst_QPdfPageNavigation::setEmptyDocument()
+{
+    QPdfDocument document;
+    QPdfPageNavigation pageNavigation;
+
+    pageNavigation.setDocument(&document);
+
+    QCOMPARE(pageNavigation.document(), &document);
+    QCOMPARE(pageNavigation.currentPage(), 0);
+    QCOMPARE(pageNavigation.pageCount(), 0);
+    QCOMPARE(pageNavigation.canGoToPreviousPage(), false);
+    QCOMPARE(pageNavigation.canGoToNextPage(), false);
+}
+
+void tst_QPdfPageNavigation::setEmptyDocumentAndLoad()
+{
+    QPdfDocument document;
+    QPdfPageNavigation pageNavigation;
+
+    pageNavigation.setDocument(&document);
+
+    QSignalSpy currentPageChangedSpy(&pageNavigation, &QPdfPageNavigation::currentPageChanged);
+    QSignalSpy pageCountChangedSpy(&pageNavigation, &QPdfPageNavigation::pageCountChanged);
+    QSignalSpy canGoToPreviousPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToPreviousPageChanged);
+    QSignalSpy canGoToNextPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToNextPageChanged);
+
+    QCOMPARE(document.load(QFINDTESTDATA("pdf-sample.pagenavigation.pdf")), QPdfDocument::NoError);
+
+    QCOMPARE(currentPageChangedSpy.count(), 0); // current page stays '0'
+    QCOMPARE(pageCountChangedSpy.count(), 1);
+    QCOMPARE(pageCountChangedSpy[0][0].toInt(), 3);
+    QCOMPARE(canGoToPreviousPageChangedSpy.count(), 0); // still no previous page available
+    QCOMPARE(canGoToNextPageChangedSpy.count(), 1);
+    QCOMPARE(canGoToNextPageChangedSpy[0][0].toBool(), true);
+}
+
+void tst_QPdfPageNavigation::setLoadedDocument()
+{
+    QPdfDocument document;
+    QCOMPARE(document.load(QFINDTESTDATA("pdf-sample.pagenavigation.pdf")), QPdfDocument::NoError);
+
+    QPdfPageNavigation pageNavigation;
+
+    QSignalSpy currentPageChangedSpy(&pageNavigation, &QPdfPageNavigation::currentPageChanged);
+    QSignalSpy pageCountChangedSpy(&pageNavigation, &QPdfPageNavigation::pageCountChanged);
+    QSignalSpy canGoToPreviousPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToPreviousPageChanged);
+    QSignalSpy canGoToNextPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToNextPageChanged);
+
+    pageNavigation.setDocument(&document);
+
+    QCOMPARE(currentPageChangedSpy.count(), 0); // current page stays '0'
+    QCOMPARE(pageCountChangedSpy.count(), 1);
+    QCOMPARE(pageCountChangedSpy[0][0].toInt(), 3);
+    QCOMPARE(canGoToPreviousPageChangedSpy.count(), 0); // still no previous page available
+    QCOMPARE(canGoToNextPageChangedSpy.count(), 1);
+    QCOMPARE(canGoToNextPageChangedSpy[0][0].toBool(), true);
+}
+
+void tst_QPdfPageNavigation::unloadDocument()
+{
+    QPdfDocument document;
+    QCOMPARE(document.load(QFINDTESTDATA("pdf-sample.pagenavigation.pdf")), QPdfDocument::NoError);
+
+    QPdfPageNavigation pageNavigation;
+    pageNavigation.setDocument(&document);
+
+    QSignalSpy currentPageChangedSpy(&pageNavigation, &QPdfPageNavigation::currentPageChanged);
+    QSignalSpy pageCountChangedSpy(&pageNavigation, &QPdfPageNavigation::pageCountChanged);
+    QSignalSpy canGoToPreviousPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToPreviousPageChanged);
+    QSignalSpy canGoToNextPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToNextPageChanged);
+
+    document.close();
+
+    QCOMPARE(currentPageChangedSpy.count(), 0); // current page stays '0'
+    QCOMPARE(pageCountChangedSpy.count(), 1);
+    QCOMPARE(pageCountChangedSpy[0][0].toInt(), 0);
+    QCOMPARE(canGoToPreviousPageChangedSpy.count(), 0); // still no previous page available
+    QCOMPARE(canGoToNextPageChangedSpy.count(), 1);
+    QCOMPARE(canGoToNextPageChangedSpy[0][0].toBool(), false);
+}
+
+void tst_QPdfPageNavigation::navigate()
+{
+    QPdfDocument document;
+    QCOMPARE(document.load(QFINDTESTDATA("pdf-sample.pagenavigation.pdf")), QPdfDocument::NoError);
+
+    QPdfPageNavigation pageNavigation;
+    pageNavigation.setDocument(&document);
+
+    QSignalSpy currentPageChangedSpy(&pageNavigation, &QPdfPageNavigation::currentPageChanged);
+    QSignalSpy canGoToPreviousPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToPreviousPageChanged);
+    QSignalSpy canGoToNextPageChangedSpy(&pageNavigation, &QPdfPageNavigation::canGoToNextPageChanged);
+
+    QCOMPARE(pageNavigation.currentPage(), 0);
+
+    // try to go to previous page while there is none
+    QCOMPARE(pageNavigation.canGoToPreviousPage(), false);
+    pageNavigation.goToPreviousPage();
+    QCOMPARE(canGoToPreviousPageChangedSpy.count(), 0);
+    QCOMPARE(pageNavigation.currentPage(), 0);
+    QCOMPARE(pageNavigation.canGoToPreviousPage(), false);
+
+    // try to go to next page
+    QCOMPARE(pageNavigation.canGoToNextPage(), true);
+    pageNavigation.goToNextPage();
+    QCOMPARE(canGoToPreviousPageChangedSpy.count(), 1);
+    QCOMPARE(canGoToNextPageChangedSpy.count(), 0);
+    QCOMPARE(currentPageChangedSpy.count(), 1);
+    QCOMPARE(pageNavigation.currentPage(), 1);
+    QCOMPARE(pageNavigation.canGoToPreviousPage(), true);
+
+    currentPageChangedSpy.clear();
+    canGoToPreviousPageChangedSpy.clear();
+    canGoToNextPageChangedSpy.clear();
+
+    // try to go to last page
+    pageNavigation.setCurrentPage(2);
+    QCOMPARE(canGoToPreviousPageChangedSpy.count(), 0);
+    QCOMPARE(canGoToNextPageChangedSpy.count(), 1);
+    QCOMPARE(currentPageChangedSpy.count(), 1);
+    QCOMPARE(pageNavigation.currentPage(), 2);
+    QCOMPARE(pageNavigation.canGoToNextPage(), false);
+
+    // check that invalid requests are ignored
+    pageNavigation.setCurrentPage(-1);
+    QCOMPARE(pageNavigation.currentPage(), 2);
+
+    pageNavigation.setCurrentPage(3);
+    QCOMPARE(pageNavigation.currentPage(), 2);
+}
+
+QTEST_MAIN(tst_QPdfPageNavigation)
+
+#include "tst_qpdfpagenavigation.moc"