Fix possible crash on project open

Improve error message on document opening
Save timeline thumbnails on project save

src/project/projectmanager.cpp

@@ -11,6 +11,7 @@ the Free Software Foundation, either version 3 of the License, or
 #include "projectmanager.h"
 #include "bin/bin.h"
 #include "bin/projectitemmodel.h"
+#include "utils/thumbnailcache.hpp"
 #include "core.h"
 #include "doc/kdenlivedoc.h"
 #include "jobs/jobmanager.h"
@@ -291,7 +292,8 @@ bool ProjectManager::saveFileAs(const QString &outputFileName)
     }
     QUrl url = QUrl::fromLocalFile(outputFileName);
     // Save timeline thumbnails
-    // m_trackView->projectView()->saveThumbnails();
+    QStringList thumbKeys = pCore->window()->getMainTimeline()->controller()->getThumbKeys();
+    ThumbnailCache::get()->saveCachedThumbs(thumbKeys);
     m_project->setUrl(url);
     // setting up autosave file in ~/.kde/data/stalefiles/kdenlive/
     // saved under file name

src/timeline2/model/builders/meltBuilder.cpp

@@ -31,14 +31,14 @@
 #include "kdenlivesettings.h"
 
 #include <KLocalizedString>
-#include <QMessageBox>
+#include <KMessageBox>
 #include <QDebug>
 #include <QSet>
 #include <mlt++/MltPlaylist.h>
 #include <mlt++/MltProducer.h>
 #include <mlt++/MltTransition.h>
 
-static QString m_errorMessage;
+static QStringList m_errorMessage;
 
 bool constructTrackFromMelt(const std::shared_ptr<TimelineItemModel> &timeline, int tid, Mlt::Tractor &track,
                             const std::unordered_map<QString, QString> &binIdCorresp, Fun &undo, Fun &redo);
@@ -140,9 +140,9 @@ bool constructTimelineFromMelt(const std::shared_ptr<TimelineItemModel> &timelin
             ok = timeline->requestCompositionInsertion(id, timeline->getTrackIndexFromPosition(t->get_b_track() - 1), t->get_a_track(), t->get_in(),
                                                        t->get_length(), &transProps, compoId, undo, redo);
             if (!ok) {
-                qDebug() << "ERROR : failed to insert composition in track " << t->get_b_track() << ", position" << t->get_in();
-                timeline->requestItemDeletion(compoId, false);
-                m_errorMessage.append(i18n("Invalid composition found on track %1 at %2.\n", t->get_b_track(), t->get_in()));
+                qDebug() << "ERROR : failed to insert composition in track " << t->get_b_track() << ", position" << t->get_in()<<", ID: "<<id<<", MLT ID: "<<t->get("id");
+                //timeline->requestItemDeletion(compoId, false);
+                m_errorMessage <<i18n("Invalid composition %1 found on track %2 at %3.", t->get("id"), t->get_b_track(), t->get_in());
                 continue;
             }
             qDebug() << "Inserted composition in track " << t->get_b_track() << ", position" << t->get_in() << "/" << t->get_out();
@@ -159,7 +159,7 @@ bool constructTimelineFromMelt(const std::shared_ptr<TimelineItemModel> &timelin
         return false;
     }
     if (!m_errorMessage.isEmpty()) {
-        QMessageBox::warning(qApp->activeWindow(), i18n("Project problems"), m_errorMessage, QMessageBox::Close);
+        KMessageBox::sorry(qApp->activeWindow(), m_errorMessage.join("\n"), i18n("Problems found in your project file"));
     }
     return true;
 }
@@ -281,7 +281,7 @@ bool constructTrackFromMelt(const std::shared_ptr<TimelineItemModel> &timeline,
             if (!ok && cid > -1) {
                 qDebug() << "ERROR : failed to insert clip in track" << tid << "position" << position;
                 timeline->requestItemDeletion(cid, false);
-                m_errorMessage.append(i18n("Invalid clip found on track %1 at %2.\n", track.get("id"), position));
+                m_errorMessage << i18n("Invalid clip %1 found on track %2 at %3.", clip->parent().get("id"), track.get("id"), position);
                 break;
             }
             qDebug() << "Inserted clip in track" << tid << "at " << position;

src/timeline2/model/clipmodel.cpp

@@ -58,9 +58,11 @@ ClipModel::ClipModel(std::shared_ptr<TimelineModel> parent, std::shared_ptr<Mlt:
         m_endlessResize = false;
     }
     QObject::connect(m_effectStack.get(), &EffectStackModel::dataChanged, [&](){
-        if (auto ptr = m_parent.lock()) {
-            QModelIndex ix = ptr->makeClipIndexFromID(m_id);
-            ptr->dataChanged(ix, ix, {TimelineModel::EffectNamesRole,TimelineModel::FadeInRole,TimelineModel::FadeOutRole});
+        if (m_currentTrackId != -1) {
+            if (auto ptr = m_parent.lock()) {
+                QModelIndex ix = ptr->makeClipIndexFromID(m_id);
+                ptr->dataChanged(ix, ix, {TimelineModel::EffectNamesRole,TimelineModel::FadeInRole,TimelineModel::FadeOutRole});
+            }
         }
     });
 }

src/timeline2/view/timelinecontroller.cpp

@@ -2031,3 +2031,15 @@ bool TimelineController::endFakeGroupMove(int clipId, int groupId, int delta_tra
     return true;
 }
 
+QStringList TimelineController::getThumbKeys()
+{
+    QStringList result;
+    for (auto clp : m_model->m_allClips) {
+        const QString binId = getClipBinId(clp.first);
+        std::shared_ptr<ProjectClip> binClip = pCore->bin()->getBinClip(binId);
+        result << binClip->hash() + QLatin1Char('#') + QString::number(clp.second->getIn()) + QStringLiteral(".png");
+        result << binClip->hash() + QLatin1Char('#') + QString::number(clp.second->getOut()) + QStringLiteral(".png");
+    }
+    result.removeDuplicates();
+    return result;
+}

src/timeline2/view/timelinecontroller.h

@@ -405,6 +405,8 @@ public:
     Q_INVOKABLE const QString getAssetName(const QString &assetId, bool isTransition);
     /** @brief Set keyboard grabbing on current selection */
     void grabCurrent();
+    /** @brief Returns keys for all used thumbnails */
+    QStringList getThumbKeys();
 
 public slots:
     void selectMultitrack();

src/utils/thumbnailcache.cpp

@@ -162,6 +162,24 @@ void ThumbnailCache::storeThumbnail(const QString &binId, int pos, const QImage
     }
 }
 
+void ThumbnailCache::saveCachedThumbs(QStringList keys)
+{
+    bool ok;
+    QDir thumbFolder = getDir(&ok);
+    if (!ok) {
+        return;
+    }
+    for (const QString &key : keys) {
+        if (!thumbFolder.exists(key) && m_volatileCache->contains(key)) {
+            QImage img = m_volatileCache->get(key);
+            if (!img.save(thumbFolder.absoluteFilePath(key))) {
+                qDebug()<<"// Error writing thumbnails to "<<thumbFolder.absolutePath();
+                break;
+            }
+        }
+    }
+}
+
 void ThumbnailCache::invalidateThumbsForClip(const QString &binId)
 {
     QMutexLocker locker(&m_mutex);

src/utils/thumbnailcache.hpp

@@ -70,6 +70,9 @@ public:
     /* @brief Removes all the thumbnails for a given clip */
     void invalidateThumbsForClip(const QString &binId);
 
+    /* @brief Save all cached thumbs to disk */
+    void saveCachedThumbs(QStringList keys);
+
 protected:
     // Constructor is protected because class is a Singleton
     ThumbnailCache();