From de6f8246ecabc3a4102c7c29ce3a7f6c4987cfec Mon Sep 17 00:00:00 2001
From: Kai Uwe Broulik <kde@privat.broulik.de>
Date: Wed, 10 Oct 2018 12:04:28 +0200
Subject: [PATCH] [Background Model] Use own QCache for thumbnails

Previously it would use an on-disk KImageCache which would never be invalidated.
Moreover, it just uses KIO::PreviewJob which does its own more clever (compares mtime and other properties) on-disk caching already.

It is using its own QCache rather than QPixmapCache to not jeopardize other caching for the potentially large wallpaper thumbnails
that are only relevant while the dialog is open.

BUG: 395447
FIXED-IN: 5.15.0

Differential Revision: https://phabricator.kde.org/D16095
---
 wallpapers/image/CMakeLists.txt          |  1 -
 wallpapers/image/backgroundlistmodel.cpp | 28 +++++++++++-------------
 wallpapers/image/backgroundlistmodel.h   |  5 ++---
 3 files changed, 15 insertions(+), 19 deletions(-)

diff --git a/wallpapers/image/CMakeLists.txt b/wallpapers/image/CMakeLists.txt
index 4c541d8cd..12a8a9c98 100644
--- a/wallpapers/image/CMakeLists.txt
+++ b/wallpapers/image/CMakeLists.txt
@@ -24,7 +24,6 @@ target_link_libraries(plasma_wallpaper_imageplugin
          KF5::KIOCore
          KF5::KIOWidgets # KFileDialog
          KF5::NewStuff
-         KF5::GuiAddons
          )
 
 if(BUILD_TESTING)
diff --git a/wallpapers/image/backgroundlistmodel.cpp b/wallpapers/image/backgroundlistmodel.cpp
index b93e23c9c..a37de09ce 100644
--- a/wallpapers/image/backgroundlistmodel.cpp
+++ b/wallpapers/image/backgroundlistmodel.cpp
@@ -39,7 +39,6 @@
 #include <QDebug>
 #include <KIO/PreviewJob>
 #include <KLocalizedString>
-#include <kimagecache.h>
 #include <kaboutdata.h>
 
 #include <KPackage/Package>
@@ -70,19 +69,16 @@ BackgroundListModel::BackgroundListModel(Image *wallpaper, QObject *parent)
     : QAbstractListModel(parent),
       m_wallpaper(wallpaper)
 {
+    m_imageCache.setMaxCost(10 * 1024 * 1024); // 10 MiB
+
     connect(&m_dirwatch, &KDirWatch::deleted, this, &BackgroundListModel::removeBackground);
 
     //TODO: on Qt 4.4 use the ui scale factor
     QFontMetrics fm(QGuiApplication::font());
     m_screenshotSize = fm.width('M') * 15;
-
-    m_imageCache = new KImageCache(QStringLiteral("plasma_wallpaper_preview"), 10485760);
 }
 
-BackgroundListModel::~BackgroundListModel()
-{
-    delete m_imageCache;
-}
+BackgroundListModel::~BackgroundListModel() = default;
 
 QHash<int, QByteArray> BackgroundListModel::BackgroundListModel::roleNames() const
 {
@@ -343,14 +339,14 @@ QVariant BackgroundListModel::data(const QModelIndex &index, int role) const
     }
 
     case ScreenshotRole: {
-        QPixmap preview = QPixmap(QSize(m_screenshotSize*1.6,
-                                                    m_screenshotSize));
-        if (m_imageCache->findPixmap(b.filePath("preferred"), &preview)) {
-            return preview;
+        const QString path = b.filePath("preferred");
+
+        QPixmap *cachedPreview = m_imageCache.object(path);
+        if (cachedPreview) {
+            return *cachedPreview;
         }
-//         qCDebug(IMAGEWALLPAPER) << "WP preferred: " << b.filePath("preferred");
-//         qCDebug(IMAGEWALLPAPER) << "WP screenshot: " << b.filePath("screenshot");
-        QUrl file = QUrl::fromLocalFile(b.filePath("preferred"));
+
+        const QUrl file = QUrl::fromLocalFile(path);
         if (!m_previewJobs.contains(file) && file.isValid()) {
 
             KFileItemList list;
@@ -451,7 +447,9 @@ void BackgroundListModel::showPreview(const KFileItem &item, const QPixmap &prev
         return;
     }
 
-    m_imageCache->insertPixmap(b.filePath("preferred"), preview);
+    const int cost = preview.width() * preview.height() * preview.depth() / 8;
+    m_imageCache.insert(b.filePath("preferred"), new QPixmap(preview), cost);
+
     //qCDebug(IMAGEWALLPAPER) << "WP preview size:" << preview.size();
     emit dataChanged(index, index);
 }
diff --git a/wallpapers/image/backgroundlistmodel.h b/wallpapers/image/backgroundlistmodel.h
index 05198bdc1..a61a02e8f 100644
--- a/wallpapers/image/backgroundlistmodel.h
+++ b/wallpapers/image/backgroundlistmodel.h
@@ -23,6 +23,7 @@
 #include "image.h"
 
 #include <QAbstractListModel>
+#include <QCache>
 #include <QPixmap>
 #include <QRunnable>
 #include <QThread>
@@ -32,8 +33,6 @@
 #include <KDirWatch>
 #include <KFileItem>
 
-#include <kimagecache.h>
-
 #include <KPackage/PackageStructure>
 
 class QEventLoop;
@@ -115,7 +114,7 @@ private:
     QHash<QString, QSize> m_sizeCache;
     QHash<QUrl, QPersistentModelIndex> m_previewJobs;
     KDirWatch m_dirwatch;
-    KImageCache* m_imageCache;
+    QCache<QString, QPixmap> m_imageCache;
 
     QString m_findToken;
     int m_screenshotSize;