refactored import function for greater robustness

The import function was written early on in the rewrite as a multithreaded
background task that was considered somewhat flawed. While it worked for the
most part, there were possibilities of race conditions that could have
potentially been fatal, particularly since media could theoretically be
deleted while the import/probe tasks were running in the background.

With the save/load functions coming in, it became even more complicated as
projects may include metadata about the footage that can't be implemented
easily when the footage is imported/probed in the background. Making importing
a modal task fixes all of these issues, it's still done in a background thread
to not hang the GUI thread, but the GUI thread can be briefly "paused" in a
user friendly way so that all these functions can be safer.

app/project/CMakeLists.txt

@@ -22,6 +22,8 @@ set(OLIVE_SOURCES
   project/project.cpp
   project/projectfilemanagerbase.h
   project/projectfilemanagerbase.cpp
+  project/projectimportmanager.h
+  project/projectimportmanager.cpp
   project/projectloadmanager.h
   project/projectloadmanager.cpp
   project/projectsavemanager.h

app/project/item/folder/folder.cpp

@@ -66,8 +66,8 @@ void Folder::Load(QXmlStreamReader *reader)
         continue;
       }
 
-      child->Load(reader);
       add_child(child);
+      child->Load(reader);
     }
   }
 }

app/project/item/footage/footage.cpp

@@ -24,6 +24,7 @@
 
 #include "common/timecodefunctions.h"
 #include "common/xmlreadloop.h"
+#include "codec/decoder.h"
 #include "ui/icons/icons.h"
 
 Footage::Footage()
@@ -48,7 +49,7 @@ void Footage::Load(QXmlStreamReader *reader)
     }
   }
 
-  // FIXME: Probe here?
+  Decoder::ProbeMedia(this);
 
   XMLReadLoop(reader, "footage") {
     if (reader->isStartElement()) {

app/project/project.cpp

@@ -20,9 +20,13 @@
 
 #include "project.h"
 
+#include <QDir>
 #include <QFileInfo>
 
 #include "common/xmlreadloop.h"
+#include "core.h"
+#include "dialog/loadsave/loadsave.h"
+#include "window/mainwindow/mainwindow.h"
 
 Project::Project()
 {

app/project/projectfilemanagerbase.cpp

@@ -6,7 +6,19 @@ ProjectFileManagerBase::ProjectFileManagerBase() :
 
 }
 
+void ProjectFileManagerBase::Start()
+{
+  Action();
+
+  emit Finished();
+}
+
 void ProjectFileManagerBase::Cancel()
 {
   cancelled_ = true;
 }
+
+const QAtomicInt &ProjectFileManagerBase::IsCancelled() const
+{
+  return cancelled_;
+}

app/project/projectfilemanagerbase.h

@@ -18,7 +18,7 @@ public slots:
    * It's recommended to invoke this through Qt signals/slots/QueuedConnection after moving this object to a separate
    * thread.
    */
-  virtual void Start() = 0;
+  void Start();
 
   /**
    * @brief Cancel the current save
@@ -28,6 +28,11 @@ public slots:
    */
   void Cancel();
 
+protected:
+  virtual void Action() = 0;
+
+  const QAtomicInt& IsCancelled() const;
+
 signals:
   void ProgressChanged(int);
 

app/project/projectimportmanager.cpp

@@ -0,0 +1,112 @@
+#include "projectimportmanager.h"
+
+#include <QDir>
+#include <QFileInfo>
+
+#include "core.h"
+#include "codec/decoder.h"
+#include "project/item/footage/footage.h"
+
+ProjectImportManager::ProjectImportManager(ProjectViewModel *model, Folder *folder, const QStringList &filenames) :
+  model_(model),
+  folder_(folder)
+{
+  foreach (const QString& f, filenames) {
+    filenames_.append(f);
+  }
+
+  file_count_ = Core::CountFilesInFileList(filenames_);
+}
+
+const int &ProjectImportManager::GetFileCount()
+{
+  return file_count_;
+}
+
+void ProjectImportManager::Action()
+{
+  QUndoCommand* command = new QUndoCommand();
+
+  int imported = 0;
+
+  Import(folder_, filenames_, imported, command);
+
+  if (IsCancelled()) {
+    delete command;
+  } else {
+    emit ImportComplete(command);
+  }
+}
+
+void ProjectImportManager::Import(Folder *folder, const QFileInfoList &import, int &counter, QUndoCommand* parent_command)
+{
+  foreach (const QFileInfo& file_info, import) {
+    if (IsCancelled()) {
+      break;
+    }
+
+    // Check if this file is a diretory
+    if (file_info.isDir()) {
+
+      // QDir::entryList only returns filenames, we can use entryInfoList() to get full paths
+      QFileInfoList entry_list = QDir(file_info.absoluteFilePath()).entryInfoList();
+
+      // Strip out "." and ".." (for some reason QDir::NoDotAndDotDot	doesn't work with entryInfoList, so we have to
+      // check manually)
+      for (int i=0;i<entry_list.size();i++) {
+        if (entry_list.at(i).fileName() == "." || entry_list.at(i).fileName() == "..") {
+          entry_list.removeAt(i);
+          i--;
+        }
+      }
+
+      // Only proceed if the empty actually has files in it
+      if (!entry_list.isEmpty()) {
+        // Create a folder corresponding to the directory
+
+        ItemPtr f = std::make_shared<Folder>();
+
+        f->set_name(file_info.fileName());
+
+        // Create undoable command that adds the items to the model
+        new ProjectViewModel::AddItemCommand(model_,
+                                             folder,
+                                             f,
+                                             parent_command);
+
+        // Recursively follow this path
+        Import(static_cast<Folder*>(f.get()), entry_list, counter, parent_command);
+      }
+
+    } else {
+
+      FootagePtr f = std::make_shared<Footage>();
+
+      f->set_filename(file_info.absoluteFilePath());
+      f->set_name(file_info.fileName());
+      f->set_timestamp(file_info.lastModified());
+
+      // Probe will fail if a project isn't set because ImageStream and its derivatives try to connect to the project's
+      // ColorManager instance
+      // FIXME: Perhaps re-think this approach at some point
+      f->set_project(model_->project());
+
+      Decoder::ProbeMedia(f.get());
+
+      f->set_project(nullptr);
+
+      if (f->status() != Footage::kInvalid) {
+        // Create undoable command that adds the items to the model
+        new ProjectViewModel::AddItemCommand(model_,
+                                             folder,
+                                             f,
+                                             parent_command);
+      }
+
+      counter++;
+
+      emit ProgressChanged((counter * 100) / file_count_);
+
+    }
+  }
+}

app/project/projectimportmanager.h

@@ -0,0 +1,37 @@
+#ifndef PROJECTIMPORTMANAGER_H
+#define PROJECTIMPORTMANAGER_H
+
+#include <QFileInfoList>
+#include <QUndoCommand>
+
+#include "projectfilemanagerbase.h"
+#include "projectviewmodel.h"
+
+class ProjectImportManager : public ProjectFileManagerBase
+{
+  Q_OBJECT
+public:
+  ProjectImportManager(ProjectViewModel* model, Folder* folder, const QStringList& filenames);
+
+  const int& GetFileCount();
+
+protected:
+  virtual void Action() override;
+
+signals:
+  void ImportComplete(QUndoCommand* command);
+
+private:
+  void Import(Folder* folder, const QFileInfoList &import, int& counter, QUndoCommand *parent_command);
+
+  ProjectViewModel* model_;
+
+  Folder* folder_;
+
+  QFileInfoList filenames_;
+
+  int file_count_;
+
+};
+
+#endif // PROJECTIMPORTMANAGER_H

app/project/projectloadmanager.cpp

@@ -9,7 +9,7 @@ ProjectLoadManager::ProjectLoadManager(const QString &filename) :
 {
 }
 
-void ProjectLoadManager::Start()
+void ProjectLoadManager::Action()
 {
   QFile project_file(filename_);
 

app/project/projectloadmanager.h

@@ -9,14 +9,8 @@ class ProjectLoadManager : public ProjectFileManagerBase
 public:
   ProjectLoadManager(const QString& filename);
 
-public slots:
-  /**
-   * @brief Start the load process
-   *
-   * It's recommended to invoke this through Qt signals/slots/QueuedConnection after moving this object to a separate
-   * thread.
-   */
-  virtual void Start() override;
+protected:
+  virtual void Action() override;
 
 signals:
   void ProjectLoaded(ProjectPtr project);

app/project/projectsavemanager.cpp

@@ -9,7 +9,7 @@ ProjectSaveManager::ProjectSaveManager(Project *project) :
 
 }
 
-void ProjectSaveManager::Start()
+void ProjectSaveManager::Action()
 {
   QFile project_file(project_->filename());
 

app/project/projectsavemanager.h

@@ -9,14 +9,8 @@ class ProjectSaveManager : public ProjectFileManagerBase
 public:
   ProjectSaveManager(Project* project);
 
-public slots:
-  /**
-   * @brief Start the save process
-   *
-   * It's recommended to invoke this through Qt signals/slots/QueuedConnection after moving this object to a separate
-   * thread.
-   */
-  virtual void Start() override;
+protected:
+  virtual void Action() override;
 
 private:
   Project* project_;

app/project/projectviewmodel.cpp

@@ -354,7 +354,7 @@ bool ProjectViewModel::dropMimeData(const QMimeData *data, Qt::DropAction action
       QUrl url = stream.readLine();
 
       if (!url.isEmpty()) {
-        urls.append(url.path());
+        urls.append(url.toLocalFile());
       }
     }