Add QPdfSearchModel, QML PdfSearchModel and PdfPageView

This enables searching a PDF for a text string and getting the
boundaries of the areas where it is found.  The boundaries are returned
as polygons intended to be rendered with PathMultiline.

PdfPageView is a QML component intended to be a drop-in viewer for use
in applications that need the most common PDF viewing functionality.
More advanced applications are free to use it as a starting point for
customization.

Task-number: QTBUG-77507
Task-number: QTBUG-77514
Change-Id: Id08ac30224e41b6cdfb9300cc4288d5750259f78
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

8 files changed, 447 insertions, 2 deletions

diff --git a/src/pdf/quick/plugin.cpp b/src/pdf/quick/plugin.cpp
index 59aca576b..664ba51ab 100644
--- a/src/pdf/quick/plugin.cpp
+++ b/src/pdf/quick/plugin.cpp
@@ -39,6 +39,7 @@
 #include <QtQml/qqmlengine.h>
 #include <QtQml/qqmlextensionplugin.h>
 #include "qquickpdfdocument_p.h"
+#include "qquickpdfsearchmodel_p.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -79,6 +80,9 @@ public:
         qmlRegisterModule(uri, 2, QT_VERSION_MINOR);
 
         qmlRegisterType<QQuickPdfDocument>(uri, 5, 15, "PdfDocument");
+        qmlRegisterType<QQuickPdfSearchModel>(uri, 5, 15, "PdfSearchModel");
+
+        qmlRegisterType(QUrl("qrc:/qt-project.org/qtpdf/qml/PdfPageView.qml"), uri, 5, 15, "PdfPageView");
     }
 };
 
diff --git a/src/pdf/quick/qml/PdfPageView.qml b/src/pdf/quick/qml/PdfPageView.qml
new file mode 100644
index 000000000..adcdc807a
--- /dev/null
+++ b/src/pdf/quick/qml/PdfPageView.qml
@@ -0,0 +1,120 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtPDF module 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+import QtQuick 2.15
+import QtQuick.Controls 2.15
+import QtQuick.Pdf 5.15
+import QtQuick.Shapes 1.15
+
+Rectangle {
+    id: paper
+    width: image.width
+    height: image.height
+    transformOrigin: Item.TopLeft
+
+    // public API
+    // TODO 5.15: required property
+    property var document: null
+    property real renderScale: 1
+    property alias sourceSize: image.sourceSize
+    property alias currentPage: image.currentFrame
+    property alias pageCount: image.frameCount
+    property alias searchString: searchModel.searchString
+    property alias status: image.status
+
+    property real __pageScale: image.paintedWidth / document.pagePointSize(image.currentFrame).width
+
+    PdfSearchModel {
+        id: searchModel
+        document: paper.document
+        page: image.currentFrame
+    }
+
+    Image {
+        id: image
+        source: document.status === PdfDocument.Ready ? document.source : ""
+        asynchronous: true
+        fillMode: Image.PreserveAspectFit
+    }
+    function reRenderIfNecessary() {
+        var newSourceWidth = image.sourceSize.width * paper.scale
+        var ratio = newSourceWidth / image.sourceSize.width
+        if (ratio > 1.1 || ratio < 0.9) {
+            image.sourceSize.width = newSourceWidth
+            image.sourceSize.height = 1
+            paper.scale = 1
+        }
+    }
+    onRenderScaleChanged: {
+        image.sourceSize.width = document.pagePointSize(image.currentFrame).width * renderScale
+        image.sourceSize.height = 0
+        paper.scale = 1
+    }
+
+    Shape {
+        anchors.fill: parent
+        opacity: 0.25
+        visible: image.status === Image.Ready
+        ShapePath {
+            strokeWidth: 1
+            strokeColor: "blue"
+            fillColor: "cyan"
+            scale: Qt.size(paper.__pageScale, paper.__pageScale)
+            PathMultiline {
+                id: searchResultBoundaries
+                paths: searchModel.matchGeometry
+            }
+        }
+    }
+    PinchHandler {
+        id: pinch
+        minimumScale: 0.1
+        maximumScale: 10
+        minimumRotation: 0
+        maximumRotation: 0
+        onActiveChanged: if (!active) paper.reRenderIfNecessary()
+        grabPermissions: PinchHandler.TakeOverForbidden // don't allow takeover if pinch has started
+    }
+    DragHandler {
+        id: pageMovingTouchDrag
+        acceptedDevices: PointerDevice.TouchScreen
+    }
+    DragHandler {
+        id: pageMovingMiddleMouseDrag
+        acceptedDevices: PointerDevice.Mouse | PointerDevice.Stylus
+        acceptedButtons: Qt.MiddleButton
+        snapMode: DragHandler.NoSnap
+    }
+}
diff --git a/src/pdf/quick/qquickpdfdocument.cpp b/src/pdf/quick/qquickpdfdocument.cpp
index f0f40c227..73b3d4537 100644
--- a/src/pdf/quick/qquickpdfdocument.cpp
+++ b/src/pdf/quick/qquickpdfdocument.cpp
@@ -95,6 +95,41 @@ void QQuickPdfDocument::setSource(QUrl source)
 }
 
 /*!
+    \qmlproperty string Document::error
+
+    This property holds a translated string representation of the current
+    error, if any.
+
+    \sa status
+*/
+QString QQuickPdfDocument::error() const
+{
+    switch (m_doc.error()) {
+    case QPdfDocument::NoError:
+        return tr("no error");
+        break;
+    case QPdfDocument::UnknownError:
+        break;
+    case QPdfDocument::DataNotYetAvailableError:
+        return tr("data not yet available");
+        break;
+    case QPdfDocument::FileNotFoundError:
+        return tr("file not found");
+        break;
+    case QPdfDocument::InvalidFileFormatError:
+        return tr("invalid file format");
+        break;
+    case QPdfDocument::IncorrectPasswordError:
+        return tr("incorrect password");
+        break;
+    case QPdfDocument::UnsupportedSecuritySchemeError:
+        return tr("unsupported security scheme");
+        break;
+    }
+    return tr("unknown error");
+}
+
+/*!
     \qmlproperty bool Document::password
 
     This property holds the document password. If the passwordRequired()
diff --git a/src/pdf/quick/qquickpdfdocument_p.h b/src/pdf/quick/qquickpdfdocument_p.h
index ee6195679..1ec7edb1a 100644
--- a/src/pdf/quick/qquickpdfdocument_p.h
+++ b/src/pdf/quick/qquickpdfdocument_p.h
@@ -64,6 +64,7 @@ class QQuickPdfDocument : public QObject, public QQmlParserStatus
     Q_PROPERTY(int pageCount READ pageCount NOTIFY pageCountChanged FINAL)
     Q_PROPERTY(QString password READ password WRITE setPassword NOTIFY passwordChanged FINAL)
     Q_PROPERTY(QPdfDocument::Status status READ status NOTIFY statusChanged FINAL)
+    Q_PROPERTY(QString error READ error NOTIFY statusChanged FINAL)
 
     Q_PROPERTY(QString title READ title NOTIFY metaDataChanged)
     Q_PROPERTY(QString subject READ subject NOTIFY metaDataChanged)
@@ -86,6 +87,8 @@ public:
     int pageCount() const { return m_doc.pageCount(); }
     QPdfDocument::Status status() const { return m_doc.status(); }
 
+    QString error() const;
+
     QString password() const { return m_doc.password(); }
     void setPassword(const QString &password);
 
@@ -115,6 +118,7 @@ private:
     QUrl m_source;
     QPdfDocument m_doc;
 
+    friend class QQuickPdfSearchModel;
     friend class QQuickPdfSelection;
 
     Q_DISABLE_COPY(QQuickPdfDocument)
diff --git a/src/pdf/quick/qquickpdfsearchmodel.cpp b/src/pdf/quick/qquickpdfsearchmodel.cpp
new file mode 100644
index 000000000..8b0e88673
--- /dev/null
+++ b/src/pdf/quick/qquickpdfsearchmodel.cpp
@@ -0,0 +1,165 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtPDF module 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 "qquickpdfsearchmodel_p.h"
+#include <QQuickItem>
+#include <QQmlEngine>
+#include <QStandardPaths>
+#include <private/qguiapplication_p.h>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \qmltype PdfSearchModel
+    \instantiates QQuickPdfSearchModel
+    \inqmlmodule QtQuick.Pdf
+    \ingroup pdf
+    \brief A representation of text search results within a PDF Document.
+    \since 5.15
+
+    PdfSearchModel provides the ability to search for text strings within a
+    document and get the geometric locations of matches on each page.
+*/
+
+QQuickPdfSearchModel::QQuickPdfSearchModel(QObject *parent)
+    : QPdfSearchModel(parent)
+{
+}
+
+QQuickPdfDocument *QQuickPdfSearchModel::document() const
+{
+    return m_quickDocument;
+}
+
+void QQuickPdfSearchModel::setDocument(QQuickPdfDocument *document)
+{
+    if (document == m_quickDocument)
+        return;
+    m_quickDocument = document;
+    QPdfSearchModel::setDocument(&document->m_doc);
+}
+
+/*!
+    \qmlproperty list<list<point>> PdfSearchModel::matchGeometry
+
+    A set of paths in a form that can be bound to the \c paths property of a
+    \l {QtQuick::PathMultiline}{PathMultiline} instance to render a batch of
+    rectangles around all the locations where search results are found:
+
+    \qml
+    PdfDocument {
+        id: doc
+    }
+    PdfSearchModel {
+        id: searchModel
+        document: doc
+        page: doc.currentPage
+    }
+    Shape {
+        ShapePath {
+            PathMultiline {
+                paths: searchModel.matchGeometry
+            }
+        }
+    }
+    \endqml
+
+    \sa PathMultiline
+*/
+QVector<QPolygonF> QQuickPdfSearchModel::matchGeometry() const
+{
+    return m_matchGeometry;
+}
+
+/*!
+    \qmlproperty string PdfSearchModel::searchString
+
+    The string to search for.
+*/
+QString QQuickPdfSearchModel::searchString() const
+{
+    return m_searchString;
+}
+
+void QQuickPdfSearchModel::setSearchString(QString searchString)
+{
+    if (m_searchString == searchString)
+        return;
+
+    m_searchString = searchString;
+    emit searchStringChanged();
+    updateResults();
+}
+
+/*!
+    \qmlproperty int PdfSearchModel::page
+
+    The page number on which to search.
+
+    \sa QtQuick::Image::currentFrame
+*/
+int QQuickPdfSearchModel::page() const
+{
+    return m_page;
+}
+
+void QQuickPdfSearchModel::setPage(int page)
+{
+    if (m_page == page)
+        return;
+
+    m_page = page;
+    emit pageChanged();
+    updateResults();
+}
+
+void QQuickPdfSearchModel::updateResults()
+{
+    if (!document() || (m_searchString.isEmpty() && !m_matchGeometry.isEmpty()) || m_page < 0 || m_page > document()->pageCount()) {
+        m_matchGeometry.clear();
+        emit matchGeometryChanged();
+    }
+    QVector<QRectF> m = QPdfSearchModel::matches(m_page, m_searchString);
+    QVector<QPolygonF> matches;
+    for (QRectF r : m)
+        matches << QPolygonF(r);
+    if (matches != m_matchGeometry) {
+        m_matchGeometry = matches;
+        emit matchGeometryChanged();
+    }
+}
+
+QT_END_NAMESPACE
diff --git a/src/pdf/quick/qquickpdfsearchmodel_p.h b/src/pdf/quick/qquickpdfsearchmodel_p.h
new file mode 100644
index 000000000..799ef825f
--- /dev/null
+++ b/src/pdf/quick/qquickpdfsearchmodel_p.h
@@ -0,0 +1,103 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtPDF module 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQUICKPDFSEARCHMODEL_P_H
+#define QQUICKPDFSEARCHMODEL_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include "qquickpdfdocument_p.h"
+#include "../api/qpdfsearchmodel.h"
+
+#include <QVariant>
+#include <QtQml/qqml.h>
+
+QT_BEGIN_NAMESPACE
+
+class QQuickPdfSearchModel : public QPdfSearchModel
+{
+    Q_OBJECT
+    Q_PROPERTY(QQuickPdfDocument *document READ document WRITE setDocument NOTIFY documentChanged)
+    Q_PROPERTY(int page READ page WRITE setPage NOTIFY pageChanged)
+    Q_PROPERTY(QString searchString READ searchString WRITE setSearchString NOTIFY searchStringChanged)
+    Q_PROPERTY(QVector<QPolygonF> matchGeometry READ matchGeometry NOTIFY matchGeometryChanged)
+
+public:
+    explicit QQuickPdfSearchModel(QObject *parent = nullptr);
+
+    QQuickPdfDocument *document() const;
+    void setDocument(QQuickPdfDocument * document);
+
+    int page() const;
+    void setPage(int page);
+
+    QString searchString() const;
+    void setSearchString(QString searchString);
+
+    QVector<QPolygonF> matchGeometry() const;
+
+signals:
+    void documentChanged();
+    void pageChanged();
+    void searchStringChanged();
+    void matchGeometryChanged();
+
+private:
+    void updateResults();
+
+private:
+    QQuickPdfDocument *m_quickDocument = nullptr;
+    QString m_searchString;
+    QVector<QPolygonF> m_matchGeometry;
+    int m_page;
+
+    Q_DISABLE_COPY(QQuickPdfSearchModel)
+};
+
+QT_END_NAMESPACE
+
+QML_DECLARE_TYPE(QQuickPdfSearchModel)
+
+#endif // QQUICKPDFSEARCHMODEL_P_H
diff --git a/src/pdf/quick/quick.pro b/src/pdf/quick/quick.pro
index eb88bc003..cda768369 100644
--- a/src/pdf/quick/quick.pro
+++ b/src/pdf/quick/quick.pro
@@ -5,12 +5,21 @@ IMPORT_VERSION = 1.0
 
 #QMAKE_DOCS = $$PWD/doc/qtquickpdf.qdocconf
 
+PDF_QML_FILES = \
+    qml/PdfPageView.qml \
+
+QML_FILES += $$PDF_QML_FILES qmldir
+
+RESOURCES += resources.qrc
+
 SOURCES += \
+    plugin.cpp \
     qquickpdfdocument.cpp \
-    plugin.cpp
+    qquickpdfsearchmodel.cpp \
 
 HEADERS += \
-    qquickpdfdocument_p.h
+    qquickpdfdocument_p.h \
+    qquickpdfsearchmodel_p.h \
 
 QT += pdf quick-private gui gui-private core core-private qml qml-private
 
diff --git a/src/pdf/quick/resources.qrc b/src/pdf/quick/resources.qrc
new file mode 100644
index 000000000..a3f34189c
--- /dev/null
+++ b/src/pdf/quick/resources.qrc
@@ -0,0 +1,5 @@
+<RCC>
+  <qresource prefix="/qt-project.org/qtpdf">
+    <file>qml/PdfPageView.qml</file>
+  </qresource>
+</RCC>