/****************************************************************************

**

** Copyright (C) 2016 The Qt Company Ltd.

** Contact: https://www.qt.io/licensing/

**

** This file is part of the QtGui 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 "qtextimagehandler_p.h"

#include <qguiapplication.h>

#include <qtextformat.h>

#include <qpainter.h>

#include <qdebug.h>

#include <qfile.h>

#include <private/qtextengine_p.h>

#include <qpalette.h>

#include <qthread.h>

QT_BEGIN_NAMESPACE

extern QString qt_findAtNxFile(const QString &baseFileName, qreal targetDevicePixelRatio,

                               qreal *sourceDevicePixelRatio);

static inline QUrl fromLocalfileOrResources(QString path)

{

    if (path.startsWith(QLatin1String(":/"))) // auto-detect resources and convert them to url

        path.prepend(QLatin1String("qrc"));

    return QUrl(path);

}

static QPixmap getPixmap(QTextDocument *doc, const QTextImageFormat &format, const qreal devicePixelRatio = 1.0)

{

    qreal sourcePixelRatio = 1.0;

    const QString name = qt_findAtNxFile(format.name(), devicePixelRatio, &sourcePixelRatio);

    const QUrl url = fromLocalfileOrResources(name);

    QPixmap pm;

    const QVariant data = doc->resource(QTextDocument::ImageResource, url);

    if (data.userType() == QMetaType::QPixmap || data.userType() == QMetaType::QImage) {

        pm = qvariant_cast<QPixmap>(data);

    } else if (data.userType() == QMetaType::QByteArray) {

        pm.loadFromData(data.toByteArray());

    }

    if (pm.isNull()) {

#if 0

        QString context;

        // ### Qt5

        QTextBrowser *browser = qobject_cast<QTextBrowser *>(doc->parent());

        if (browser)

            context = browser->source().toString();

#endif

        // try direct loading

        QImage img;

        if (name.isEmpty() || !img.load(name))

            return QPixmap(QLatin1String(":/qt-project.org/styles/commonstyle/images/file-16.png"));

        pm = QPixmap::fromImage(img);

        doc->addResource(QTextDocument::ImageResource, url, pm);

    }

    if (name.contains(QLatin1String("@2x")))

        pm.setDevicePixelRatio(sourcePixelRatio);

    return pm;

}

static QSize getPixmapSize(QTextDocument *doc, const QTextImageFormat &format)

{

    QPixmap pm;

    const bool hasWidth = format.hasProperty(QTextFormat::ImageWidth);

    const int width = qRound(format.width());

    const bool hasHeight = format.hasProperty(QTextFormat::ImageHeight);

    const int height = qRound(format.height());

    QSize size(width, height);

    if (!hasWidth || !hasHeight) {

        pm = getPixmap(doc, format);

        const int pmWidth = pm.width() / pm.devicePixelRatio();

        const int pmHeight = pm.height() / pm.devicePixelRatio();

        if (!hasWidth) {

            if (!hasHeight)

                size.setWidth(pmWidth);

            else

                size.setWidth(qRound(height * (pmWidth / (qreal) pmHeight)));

        }

        if (!hasHeight) {

            if (!hasWidth)

                size.setHeight(pmHeight);

            else

                size.setHeight(qRound(width * (pmHeight / (qreal) pmWidth)));

        }

    }

    qreal scale = 1.0;

    QPaintDevice *pdev = doc->documentLayout()->paintDevice();

    if (pdev) {

        if (pm.isNull())

            pm = getPixmap(doc, format);

        if (!pm.isNull())

            scale = qreal(pdev->logicalDpiY()) / qreal(qt_defaultDpi());

    }

    size *= scale;

    return size;

}

static QImage getImage(QTextDocument *doc, const QTextImageFormat &format, const qreal devicePixelRatio = 1.0)

{

    qreal sourcePixelRatio = 1.0;

    const QString name = qt_findAtNxFile(format.name(), devicePixelRatio, &sourcePixelRatio);

    const QUrl url = fromLocalfileOrResources(name);

    QImage image;

    const QVariant data = doc->resource(QTextDocument::ImageResource, url);

    if (data.userType() == QMetaType::QImage) {

        image = qvariant_cast<QImage>(data);

    } else if (data.userType() == QMetaType::QByteArray) {

        image.loadFromData(data.toByteArray());

    }

    if (image.isNull()) {

#if 0

        QString context;

        // ### Qt5

        QTextBrowser *browser = qobject_cast<QTextBrowser *>(doc->parent());

        if (browser)

            context = browser->source().toString();

#endif

        // try direct loading

        if (name.isEmpty() || !image.load(name))

            return QImage(QLatin1String(":/qt-project.org/styles/commonstyle/images/file-16.png"));

        doc->addResource(QTextDocument::ImageResource, url, image);

    }

    if (sourcePixelRatio != 1.0)

        image.setDevicePixelRatio(sourcePixelRatio);

    return image;

}

static QSize getImageSize(QTextDocument *doc, const QTextImageFormat &format)

{

    QImage image;

    const bool hasWidth = format.hasProperty(QTextFormat::ImageWidth);

    const int width = qRound(format.width());

    const bool hasHeight = format.hasProperty(QTextFormat::ImageHeight);

    const int height = qRound(format.height());

    QSize size(width, height);

    if (!hasWidth || !hasHeight) {

        image = getImage(doc, format);

        if (!hasWidth)

            size.setWidth(image.width() / image.devicePixelRatio());

        if (!hasHeight)

            size.setHeight(image.height() / image.devicePixelRatio());

    }

    qreal scale = 1.0;

    QPaintDevice *pdev = doc->documentLayout()->paintDevice();

    if (pdev) {

        if (image.isNull())

            image = getImage(doc, format);

        if (!image.isNull())

            scale = qreal(pdev->logicalDpiY()) / qreal(qt_defaultDpi());

    }

    size *= scale;

    return size;

}

QTextImageHandler::QTextImageHandler(QObject *parent)

    : QObject(parent)

{

}

QSizeF QTextImageHandler::intrinsicSize(QTextDocument *doc, int posInDocument, const QTextFormat &format)

{

    Q_UNUSED(posInDocument)

    const QTextImageFormat imageFormat = format.toImageFormat();

    if (QCoreApplication::instance()->thread() != QThread::currentThread())

        return getImageSize(doc, imageFormat);

    return getPixmapSize(doc, imageFormat);

}

QImage QTextImageHandler::image(QTextDocument *doc, const QTextImageFormat &imageFormat)

{

    Q_ASSERT(doc != nullptr);

    return getImage(doc, imageFormat);

}

void QTextImageHandler::drawObject(QPainter *p, const QRectF &rect, QTextDocument *doc, int posInDocument, const QTextFormat &format)

{

    Q_UNUSED(posInDocument)

        const QTextImageFormat imageFormat = format.toImageFormat();

    if (QCoreApplication::instance()->thread() != QThread::currentThread()) {

        const QImage image = getImage(doc, imageFormat, p->device()->devicePixelRatioF());

        p->drawImage(rect, image, image.rect());

    } else {

        const QPixmap pixmap = getPixmap(doc, imageFormat, p->device()->devicePixelRatioF());

        p->drawPixmap(rect, pixmap, pixmap.rect());

    }

}

QT_END_NAMESPACE

#include "moc_qtextimagehandler_p.cpp"