From 69149b3e4580c342dc0866e841a76fd19218073c Mon Sep 17 00:00:00 2001
From: Daguerreo <maurizio.ingrassia@gmail.com>
Date: Mon, 26 Apr 2021 18:02:44 +0200
Subject: [PATCH] Added FibonacciModel in calculator example showing dynamic 
 output ports

---
 examples/calculator/FibonacciModel.cpp | 150 +++++++++++++++++++++++++
 examples/calculator/FibonacciModel.hpp |  78 +++++++++++++
 examples/calculator/main.cpp           |   7 +-
 3 files changed, 233 insertions(+), 2 deletions(-)
 create mode 100644 examples/calculator/FibonacciModel.cpp
 create mode 100644 examples/calculator/FibonacciModel.hpp

diff --git a/examples/calculator/FibonacciModel.cpp b/examples/calculator/FibonacciModel.cpp
new file mode 100644
index 00000000..f9e93b6e
--- /dev/null
+++ b/examples/calculator/FibonacciModel.cpp
@@ -0,0 +1,150 @@
+#include "FibonacciModel.hpp"
+
+#include <nodes/Connection>
+
+int fibo(int n)
+{
+   if(n<=1) return 1;
+
+   int fibo = 0;
+   int fibo1 = 1;
+   int fibo2 = 1;
+   int i = 1;
+
+   while (i<n) {
+      fibo = fibo1 + fibo2;
+      ++i;
+      fibo2 = fibo1;
+      fibo1 = fibo;
+   }
+
+   return fibo;
+}
+
+FibonacciModel::FibonacciModel()
+   : NodeDataModel(),
+     _indexCounter(1)
+{
+}
+
+unsigned int
+FibonacciModel::
+   nPorts(QtNodes::PortType portType) const
+{
+   if (portType == PortType::In)
+      return 0;
+   else
+      return std::max(1, _indexCounter);
+}
+
+bool
+FibonacciModel::
+   hasDynamicPorts(QtNodes::PortType portType) const
+{
+   if(portType == PortType::Out)
+      return true;
+
+   return false;
+}
+
+QtNodes::NodeDataType
+FibonacciModel::
+   dataType(QtNodes::PortType, QtNodes::PortIndex) const
+{
+   return DecimalData().type();
+}
+
+std::shared_ptr<QtNodes::NodeData>
+FibonacciModel::
+   outData(QtNodes::PortIndex port)
+{
+   return std::make_shared<DecimalData>(fibo(port));
+}
+
+void
+FibonacciModel::
+   setInData(std::shared_ptr<QtNodes::NodeData>, QtNodes::PortIndex)
+{
+}
+
+QString
+FibonacciModel::
+   caption() const
+{
+   return QStringLiteral("Fibonacci");
+}
+
+bool
+FibonacciModel::
+   portCaptionVisible(QtNodes::PortType, QtNodes::PortIndex) const
+{
+   return true;
+}
+
+QString
+FibonacciModel::
+   portCaption(QtNodes::PortType, QtNodes::PortIndex portIndex) const
+{
+   return QString("Fibo %1").arg(portIndex);
+}
+
+QString
+FibonacciModel::
+   name() const
+{
+   return QStringLiteral("Fibonacci");
+}
+
+QtNodes::NodeValidationState
+FibonacciModel::
+   validationState() const
+{
+   return _modelValidationState;
+}
+
+QString
+FibonacciModel::
+   validationMessage() const
+{
+   return _modelValidationError;
+}
+
+void FibonacciModel::restore(const QJsonObject& obj)
+{
+   int out = obj["dynamic_outputs"].toInt();
+   if(out > 1){
+      _indexCounter = out;
+   }
+}
+
+void FibonacciModel::outputConnectionCreated(const QtNodes::Connection& c)
+{
+  auto outIndex = static_cast<int>(c.getPortIndex(QtNodes::PortType::Out));
+
+  // Create a new port only if the last port is connected and the connection is completed
+  if (outIndex == _indexCounter-1 && c.complete()){
+    ++_indexCounter;
+    Q_EMIT portAdded(PortType::Out, _indexCounter-1);
+  }
+}
+
+void FibonacciModel::outputConnectionDeleted(const QtNodes::Connection& c)
+{
+   auto outIndex = static_cast<int>(c.getPortIndex(QtNodes::PortType::Out));
+
+   // outIndex >= 0 ---> dynamic remove only for ports exceding 0
+   // !c.complete() ---> port is removed only if connection is removed e and mouse released
+   // outIndex != _indexCounter-1 --> if you start a connection from the last port but do not connect it
+   // the connection is destroyed as incomplete, but the port must not be removed because that
+   // port is already the last one
+
+   if ((outIndex >= 0) && (!c.complete()) && (outIndex != _indexCounter-1)){
+      Q_EMIT portRemoved(PortType::Out, outIndex);
+      --_indexCounter;
+
+      // Recalculate ports
+      for(int i = outIndex; i<_indexCounter; ++i){
+         Q_EMIT dataUpdated(i);
+      }
+   }
+}
diff --git a/examples/calculator/FibonacciModel.hpp b/examples/calculator/FibonacciModel.hpp
new file mode 100644
index 00000000..7d0ee7c0
--- /dev/null
+++ b/examples/calculator/FibonacciModel.hpp
@@ -0,0 +1,78 @@
+#pragma once
+
+#include <nodes/NodeDataModel>
+#include <nodes/Connection>
+
+#include "DecimalData.hpp"
+
+using QtNodes::PortType;
+using QtNodes::PortIndex;
+using QtNodes::NodeData;
+using QtNodes::NodeDataType;
+using QtNodes::NodeDataModel;
+using QtNodes::NodeValidationState;
+
+class FibonacciModel : public NodeDataModel
+{
+   Q_OBJECT
+
+public:
+  FibonacciModel();
+
+  unsigned int
+  nPorts(PortType portType) const override;
+
+  bool
+  hasDynamicPorts(PortType portType) const override;
+
+  NodeDataType
+  dataType(PortType portType, PortIndex portIndex) const override;
+
+  std::shared_ptr<NodeData>
+  outData(PortIndex port) override;
+
+  void
+  setInData(std::shared_ptr<NodeData> data, PortIndex portIndex) override;
+
+public:
+
+  QString
+  caption() const override;
+
+  bool
+  portCaptionVisible(PortType portType, PortIndex portIndex) const override;
+
+  QString
+  portCaption(PortType portType, PortIndex portIndex) const override;
+
+  QString
+  name() const override;
+
+public:
+
+  QWidget *
+  embeddedWidget() override { return nullptr; }
+
+  NodeValidationState
+  validationState() const override;
+
+  QString
+  validationMessage() const override;
+
+private:
+
+  void
+  restore(const QJsonObject& obj) override;
+
+  void
+  outputConnectionCreated(const QtNodes::Connection& c) override;
+
+  void
+  outputConnectionDeleted(const QtNodes::Connection& c) override;
+
+private:
+   int _indexCounter;
+
+   NodeValidationState _modelValidationState = NodeValidationState::Warning;
+   QString _modelValidationError = QString("Missing or incorrect inputs");
+};
diff --git a/examples/calculator/main.cpp b/examples/calculator/main.cpp
index ae425205..b604b9f1 100644
--- a/examples/calculator/main.cpp
+++ b/examples/calculator/main.cpp
@@ -20,6 +20,7 @@
 #include "AccumulatorModel.hpp"
 #include "MinModel.hpp"
 #include "MaxModel.hpp"
+#include "FibonacciModel.hpp"
 #include "Converters.hpp"
 
 using QtNodes::DataModelRegistry;
@@ -49,9 +50,11 @@ registerDataModels()
 
   ret->registerModel<ModuloModel>("Operators");
 
-  ret->registerModel<MinModel>("Operators");
+  ret->registerModel<MinModel>("Special");
 
-  ret->registerModel<MaxModel>("Operators");
+  ret->registerModel<MaxModel>("Special");
+
+  ret->registerModel<FibonacciModel>("Special");
 
   ret->registerTypeConverter(std::make_pair(DecimalData().type(),
                                             IntegerData().type()),