export: allow exporting subtitles to sidecar files

app/task/export/export.cpp

@@ -58,7 +58,14 @@ bool ExportTask::Run()
     params_.SetFilename(FileFunctions::GetSafeTemporaryFilename(real_filename));
   }
 
-  encoder_ = Encoder::CreateFromID(params_.encoder(), params_);
+  // If we're exporting to a sidecar subtitle file, disable the subtitles in the main encoder
+  bool subtitles_enabled = params_.subtitles_enabled();
+  ExportParams sidecar_params = params_;
+  if (subtitles_enabled && params_.subtitles_are_sidecar()) {
+    params_.DisableSubtitles();
+  }
+
+  encoder_ = std::shared_ptr<Encoder>(Encoder::CreateFromParams(params_));
 
   if (!encoder_) {
     SetError(tr("Failed to create encoder"));
@@ -67,10 +74,38 @@ bool ExportTask::Run()
 
   if (!encoder_->Open()) {
     SetError(tr("Failed to open file: %1").arg(encoder_->GetError()));
-    encoder_->deleteLater();
     return false;
   }
 
+  if (subtitles_enabled && params_.subtitles_are_sidecar()) {
+    // Construct sidecar params
+    sidecar_params.DisableVideo();
+    sidecar_params.DisableAudio();
+
+    QString sidecar_filename;
+    {
+      QFileInfo fi(real_filename);
+      sidecar_filename = fi.completeBaseName();
+      sidecar_filename.append('.');
+      sidecar_filename.append(ExportFormat::GetExtension(sidecar_params.subtitle_sidecar_fmt()));
+      sidecar_filename = fi.dir().filePath(sidecar_filename);
+    }
+    sidecar_params.SetFilename(sidecar_filename);
+
+    subtitle_encoder_ = std::shared_ptr<Encoder>(Encoder::CreateFromFormat(sidecar_params.subtitle_sidecar_fmt(), sidecar_params));
+    if (!subtitle_encoder_) {
+      SetError(tr("Failed to create subtitle encoder"));
+      return false;
+    }
+
+    if (!subtitle_encoder_->Open()) {
+      SetError(tr("Failed to open subtitle sidecar file: %1").arg(sidecar_filename));
+      return false;
+    }
+  } else {
+    subtitle_encoder_ = encoder_;
+  }
+
   if (params_.has_custom_range()) {
     // Render custom range only
     range = params_.custom_range();
@@ -121,7 +156,7 @@ bool ExportTask::Run()
     audio_range = {range};
   }
 
-  if (params_.subtitles_enabled()) {
+  if (subtitles_enabled) {
     subtitle_range = range;
   }
 
@@ -132,13 +167,18 @@ bool ExportTask::Run()
   bool success = true;
 
   encoder_->Close();
-
   if (!encoder_->GetError().isEmpty()) {
     SetError(encoder_->GetError());
     success = false;
   }
 
-  delete encoder_;
+  if (subtitle_encoder_ != encoder_) {
+    subtitle_encoder_->Close();
+    if (!subtitle_encoder_->GetError().isEmpty()) {
+      SetError(subtitle_encoder_->GetError());
+      success = false;
+    }
+  }
 
   // If cancelled, delete the file we made, which is always a file we created since we write to a
   // temp file during the actual encoding process
@@ -209,8 +249,8 @@ bool ExportTask::AudioDownloaded(const TimeRange &range, const SampleBuffer &sam
 
 bool ExportTask::EncodeSubtitle(const SubtitleBlock *sub)
 {
-  if (!encoder_->WriteSubtitle(sub)) {
-    SetError(encoder_->GetError());
+  if (!subtitle_encoder_->WriteSubtitle(sub)) {
+    SetError(subtitle_encoder_->GetError());
     return false;
   } else {
     return true;