use strings to connect nodes

This makes the node system somewhat more high-level with the intent of making
working with them far more flexible and stable. By making the architecture more
abstracted, it becomes far less rigid which should allow us to do even more
with it and make it much less crash prone.

app/node/input/media/media.cpp

@@ -25,13 +25,12 @@
 
 namespace olive {
 
+const QString MediaInput::kFootageInput = QStringLiteral("footage_in");
+
 MediaInput::MediaInput() :
   connected_footage_(nullptr)
 {
-  footage_input_ = new NodeInput(this, QStringLiteral("footage_in"), NodeValue::kFootage);
-  footage_input_->SetConnectable(false);
-  footage_input_->SetKeyframable(false);
-  connect(footage_input_, &NodeInput::ValueChanged, this, &MediaInput::FootageChanged);
+  AddInput(kFootageInput, NodeValue::kFootage, InputFlags(kInputFlagNotConnectable | kInputFlagNotKeyframable));
 }
 
 QVector<Node::CategoryID> MediaInput::Category() const
@@ -41,21 +40,23 @@ QVector<Node::CategoryID> MediaInput::Category() const
 
 Stream *MediaInput::stream() const
 {
-  return Node::ValueToPtr<Stream>(footage_input_->GetStandardValue());
+  return Node::ValueToPtr<Stream>(GetStandardValue(kFootageInput));
 }
 
 void MediaInput::SetStream(Stream* s)
 {
-  footage_input_->SetStandardValue(Node::PtrToValue(s));
+  SetStandardValue(kFootageInput, Node::PtrToValue(s));
 }
 
 void MediaInput::Retranslate()
 {
-  footage_input_->set_name(tr("Media"));
+  SetInputName(kFootageInput, tr("Media"));
 }
 
-NodeValueTable MediaInput::Value(NodeValueDatabase &value) const
+NodeValueTable MediaInput::Value(const QString &output, NodeValueDatabase &value) const
 {
+  Q_UNUSED(output)
+
   NodeValueTable table = value.Merge();
 
   if (connected_footage_) {
@@ -68,28 +69,32 @@ NodeValueTable MediaInput::Value(NodeValueDatabase &value) const
   return table;
 }
 
-void MediaInput::FootageChanged()
+void MediaInput::InputValueChangedEvent(const QString &input, int element)
 {
-  Stream* new_footage = footage_input_->GetStandardValue().value<Stream*>();
+  Q_UNUSED(element)
 
-  if (new_footage == connected_footage_) {
-    return;
-  }
+  if (input == kFootageInput) {
+    Stream* new_footage = stream();
 
-  if (connected_footage_) {
-    disconnect(connected_footage_, &Stream::ParametersChanged, this, &MediaInput::FootageParametersChanged);
-  }
+    if (new_footage == connected_footage_) {
+      return;
+    }
 
-  connected_footage_ = new_footage;
+    if (connected_footage_) {
+      disconnect(connected_footage_, &Stream::ParametersChanged, this, &MediaInput::FootageParametersChanged);
+    }
 
-  if (connected_footage_) {
-    connect(connected_footage_, &Stream::ParametersChanged, this, &MediaInput::FootageParametersChanged);
+    connected_footage_ = new_footage;
+
+    if (connected_footage_) {
+      connect(connected_footage_, &Stream::ParametersChanged, this, &MediaInput::FootageParametersChanged);
+    }
   }
 }
 
 void MediaInput::FootageParametersChanged()
 {
-  InvalidateCache(TimeRange(0, RATIONAL_MAX), InputConnection(footage_input_));
+  InvalidateCache(TimeRange(0, RATIONAL_MAX), kFootageInput);
 }
 
 }

app/node/input/media/media.h

@@ -63,16 +63,16 @@ public:
 
   virtual void Retranslate() override;
 
-  virtual NodeValueTable Value(NodeValueDatabase& value) const override;
+  virtual NodeValueTable Value(const QString& output, NodeValueDatabase& value) const override;
+
+  static const QString kFootageInput;
 
 protected:
-  NodeInput* footage_input_;
+  virtual void InputValueChangedEvent(const QString& input, int element);
 
   Stream* connected_footage_;
 
 private slots:
-  void FootageChanged();
-
   void FootageParametersChanged();
 
 };

app/node/input/time/timeinput.cpp

@@ -51,8 +51,10 @@ QString TimeInput::Description() const
   return tr("Generates the time (in seconds) at this frame");
 }
 
-NodeValueTable TimeInput::Value(NodeValueDatabase &value) const
+NodeValueTable TimeInput::Value(const QString &output, NodeValueDatabase &value) const
 {
+  Q_UNUSED(output)
+
   NodeValueTable table = value.Merge();
 
   table.Push(NodeValue::kFloat,

app/node/input/time/timeinput.h

@@ -38,7 +38,7 @@ public:
   virtual QVector<CategoryID> Category() const override;
   virtual QString Description() const override;
 
-  virtual NodeValueTable Value(NodeValueDatabase& value) const override;
+  virtual NodeValueTable Value(const QString& output, NodeValueDatabase& value) const override;
 
   virtual void Hash(QCryptographicHash& hash, const rational& time) const override;