From a14c24ad272b3b58bf596975485149c5317f01ee Mon Sep 17 00:00:00 2001
From: itsmattkc <itsmattkc@gmail.com>
Date: Thu, 19 Jul 2018 20:44:52 +0100
Subject: [PATCH] fixed crash with missing media

---
 io/previewgenerator.cpp | 17 ++++++++++++-----
 panels/project.cpp      | 20 +++++++++++++-------
 panels/project.h        |  1 +
 3 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/io/previewgenerator.cpp b/io/previewgenerator.cpp
index 7cd068b5a..9f9899e30 100644
--- a/io/previewgenerator.cpp
+++ b/io/previewgenerator.cpp
@@ -28,21 +28,28 @@ void PreviewGenerator::parse_media() {
         if (avcodec_find_decoder(fmt_ctx->streams[i]->codecpar->codec_id) == NULL) {
             qDebug() << "[ERROR] Unsupported codec in stream %d.\n";
         } else {
-            MediaStream* ms = new MediaStream();
-            ms->preview_done = false;
-            ms->file_index = i;
+            MediaStream* ms = media->get_stream_from_file_index(i);
+            bool append = false;
+            if (ms == NULL) {
+                ms = new MediaStream();
+                ms->preview_done = false;
+                ms->file_index = i;
+                append = true;
+            }
             if (fmt_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
                 bool infinite_length = (fmt_ctx->streams[i]->avg_frame_rate.den == 0);
                 ms->video_width = fmt_ctx->streams[i]->codecpar->width;
                 ms->video_height = fmt_ctx->streams[i]->codecpar->height;
                 ms->video_frame_rate = (infinite_length) ? 0 : av_q2d(fmt_ctx->streams[i]->avg_frame_rate);
                 ms->infinite_length = infinite_length;
-                media->video_tracks.append(ms);
+                if (append) media->video_tracks.append(ms);
             } else if (fmt_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
                 ms->audio_channels = fmt_ctx->streams[i]->codecpar->channels;
                 ms->audio_layout = fmt_ctx->streams[i]->codecpar->channel_layout;
                 ms->audio_frequency = fmt_ctx->streams[i]->codecpar->sample_rate;
-                media->audio_tracks.append(ms);
+                if (append) media->audio_tracks.append(ms);
+            } else {
+                delete ms;
             }
         }
     }
diff --git a/panels/project.cpp b/panels/project.cpp
index 7aaa074a4..e184e48d6 100644
--- a/panels/project.cpp
+++ b/panels/project.cpp
@@ -122,6 +122,16 @@ void Project::new_sequence(TimelineAction *ta, Sequence *s, bool open, QTreeWidg
     project_changed = true;
 }
 
+void Project::start_preview_generator(QTreeWidgetItem* item, Media* media) {
+    // set up throbber animation
+    MediaThrobber* throbber = new MediaThrobber(item);
+
+    PreviewGenerator* pg = new PreviewGenerator(item, media);
+    connect(pg, SIGNAL(set_icon(int)), throbber, SLOT(stop(int)));
+    connect(pg, SIGNAL(finished()), pg, SLOT(deleteLater()));
+    pg->start(QThread::LowPriority);
+}
+
 QTreeWidgetItem* Project::import_file(QString file) {
     QTreeWidgetItem* item = new_item();
     Media* m = new Media();
@@ -129,13 +139,8 @@ QTreeWidgetItem* Project::import_file(QString file) {
     m->name = file.mid(file.lastIndexOf('/')+1);
     set_media_of_tree(item, m);
 
-    // set up throbber animation
-    MediaThrobber* throbber = new MediaThrobber(item);
-
     // generate waveform/thumbnail in another thread
-    PreviewGenerator* pg = new PreviewGenerator(item, m);
-    connect(pg, SIGNAL(set_icon(int)), throbber, SLOT(stop(int)));
-    pg->start(QThread::LowPriority);
+    start_preview_generator(item, m);
 
     return item;
 }
@@ -541,7 +546,8 @@ bool Project::load_worker(QFile& f, QXmlStreamReader& stream, int type) {
                                 find_loaded_folder_by_id(folder)->addChild(item);
                             }
 
-                            m->ready = true;
+                            // analyze media to see if it's the same
+                            start_preview_generator(item, m);
 
                             loaded_media.append(m);
                         }
diff --git a/panels/project.h b/panels/project.h
index 8b7231d3f..7b4e86b0d 100644
--- a/panels/project.h
+++ b/panels/project.h
@@ -82,6 +82,7 @@ private:
     QTreeWidgetItem* find_loaded_folder_by_id(int id);
     void add_recent_project(QString url);
     void get_media_from_table(QList<QTreeWidgetItem*> items, QList<QTreeWidgetItem*>& list, int type);
+    void start_preview_generator(QTreeWidgetItem* item, Media* media);
 private slots:
     void rename_media(QTreeWidgetItem* item, int column);
     void clear_recent_projects();