pollymc/launcher/ui/widgets/VariableSizedImageObject.cpp
flow 756d933d1a
fix: bind image fetch callback lambda to the parent object
Fixes a possible crash with the callback being called after the image
object was already deleted.

Signed-off-by: flow <flowlnlnln@gmail.com>
2022-12-12 23:51:22 -03:00

128 lines
4.4 KiB
C++

// SPDX-License-Identifier: GPL-3.0-only
/*
* PolyMC - Minecraft Launcher
* Copyright (c) 2022 flowln <flowlnlnln@gmail.com>
*
* This program 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, version 3.
*
* This program 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, see <https://www.gnu.org/licenses/>.
*/
#include "VariableSizedImageObject.h"
#include <QAbstractTextDocumentLayout>
#include <QDebug>
#include <QPainter>
#include <QTextObject>
#include "Application.h"
#include "net/NetJob.h"
enum FormatProperties { ImageData = QTextFormat::UserProperty + 1 };
QSizeF VariableSizedImageObject::intrinsicSize(QTextDocument* doc, int posInDocument, const QTextFormat& format)
{
Q_UNUSED(posInDocument);
auto image = qvariant_cast<QImage>(format.property(ImageData));
auto size = image.size();
// Get the width of the text content to make the image similar sized.
// doc->textWidth() includes the margin, so we need to remove it.
auto doc_width = doc->textWidth() - 2 * doc->documentMargin();
if (size.width() > doc_width)
size *= doc_width / (double)size.width();
return { size };
}
void VariableSizedImageObject::drawObject(QPainter* painter,
const QRectF& rect,
QTextDocument* doc,
int posInDocument,
const QTextFormat& format)
{
if (!format.hasProperty(ImageData)) {
QUrl image_url{ qvariant_cast<QString>(format.property(QTextFormat::ImageName)) };
if (m_fetching_images.contains(image_url))
return;
loadImage(doc, image_url, posInDocument);
return;
}
auto image = qvariant_cast<QImage>(format.property(ImageData));
painter->setRenderHint(QPainter::RenderHint::SmoothPixmapTransform);
painter->drawImage(rect, image);
}
void VariableSizedImageObject::flush()
{
m_fetching_images.clear();
}
void VariableSizedImageObject::parseImage(QTextDocument* doc, QImage image, int posInDocument)
{
QTextCursor cursor(doc);
cursor.setPosition(posInDocument);
cursor.setKeepPositionOnInsert(true);
auto image_char_format = cursor.charFormat();
image_char_format.setObjectType(QTextFormat::ImageObject);
image_char_format.setProperty(ImageData, image);
// Qt doesn't allow us to modify the properties of an existing object in the document.
// So we remove the old one and add the new one with the ImageData property set.
cursor.deleteChar();
cursor.insertText(QString(QChar::ObjectReplacementCharacter), image_char_format);
}
void VariableSizedImageObject::loadImage(QTextDocument* doc, const QUrl& source, int posInDocument)
{
m_fetching_images.insert(source);
MetaEntryPtr entry = APPLICATION->metacache()->resolveEntry(
m_meta_entry,
QString("images/%1").arg(QString(QCryptographicHash::hash(source.toEncoded(), QCryptographicHash::Algorithm::Sha1).toHex())));
auto job = new NetJob(QString("Load Image: %1").arg(source.fileName()), APPLICATION->network());
job->addNetAction(Net::Download::makeCached(source, entry));
auto full_entry_path = entry->getFullPath();
auto source_url = source;
connect(job, &NetJob::succeeded, this, [this, doc, full_entry_path, source_url, posInDocument] {
qDebug() << "Loaded resource at" << full_entry_path;
// If we flushed, don't proceed.
if (!m_fetching_images.contains(source_url))
return;
QImage image(full_entry_path);
doc->addResource(QTextDocument::ImageResource, source_url, image);
parseImage(doc, image, posInDocument);
// This size hack is needed to prevent the content from being laid out in an area smaller
// than the total width available (weird).
auto size = doc->pageSize();
doc->adjustSize();
doc->setPageSize(size);
m_fetching_images.remove(source_url);
});
connect(job, &NetJob::finished, job, &NetJob::deleteLater);
job->start();
}