Added PropertyExpressionEngine class.

src/App/PropertyExpressionEngine.h

@@ -0,0 +1,148 @@
+/***************************************************************************
+ *   Copyright (c) Eivind Kvedalen (eivind@kvedalen.name) 2015             *
+ *                                                                         *
+ *   This file is part of the FreeCAD CAx development system.              *
+ *                                                                         *
+ *   This library is free software; you can redistribute it and/or         *
+ *   modify it under the terms of the GNU Library General Public           *
+ *   License as published by the Free Software Foundation; either          *
+ *   version 2 of the License, or (at your option) any later version.      *
+ *                                                                         *
+ *   This library  is distributed in the hope that it will be useful,      *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU Library General Public License for more details.                  *
+ *                                                                         *
+ *   You should have received a copy of the GNU Library General Public     *
+ *   License along with this library; see the file COPYING.LIB. If not,    *
+ *   write to the Free Software Foundation, Inc., 59 Temple Place,         *
+ *   Suite 330, Boston, MA  02111-1307, USA                                *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef EXPRESSIONENGINE_H
+#define EXPRESSIONENGINE_H
+
+#include <boost/unordered/unordered_map.hpp>
+#include <boost/function.hpp>
+#include <boost/graph/adjacency_list.hpp>
+#include <boost/graph/topological_sort.hpp>
+#include <App/Property.h>
+#include <App/Expression.h>
+#include <set>
+
+namespace Base {
+class Writer;
+class XMLReader;
+}
+
+namespace App {
+
+class DocumentObject;
+class DocumentObjectExecReturn;
+class ObjectIdentifier;
+class Expression;
+
+class AppExport PropertyExpressionEngine : public App::Property
+{
+    TYPESYSTEM_HEADER();
+public:
+
+    typedef boost::function<std::string (const App::ObjectIdentifier & path, boost::shared_ptr<const App::Expression> expr)> ValidatorFunc;
+
+    /**
+     * @brief The ExpressionInfo struct encapsulates an expression and a comment.
+     */
+
+    struct ExpressionInfo {
+        boost::shared_ptr<App::Expression> expression; /**< The actual expression tree */
+        std::string comment; /**< Optional comment for this expression */
+
+        ExpressionInfo(boost::shared_ptr<App::Expression> expression = boost::shared_ptr<App::Expression>(), const char * comment = 0) {
+            this->expression = expression;
+            if (comment)
+                this->comment = comment;
+        }
+
+        ExpressionInfo(const ExpressionInfo & other) {
+            expression = other.expression;
+            comment = other.comment;
+        }
+
+        ExpressionInfo & operator=(const ExpressionInfo & other) {
+            expression = other.expression;
+            comment = other.comment;
+            return *this;
+        }
+    };
+
+    PropertyExpressionEngine();
+    ~PropertyExpressionEngine();
+
+    unsigned int getMemSize (void) const;
+
+    void setValue() { } // Dummy
+
+    Property *Copy(void) const;
+
+    void Paste(const Property &from);
+
+    void Save (Base::Writer & writer) const;
+
+    void Restore(Base::XMLReader &reader);
+
+    void setValue(const App::ObjectIdentifier &path, boost::shared_ptr<App::Expression> expr, const char * comment = 0);
+
+    const boost::any getValue(const App::ObjectIdentifier & path) const;
+
+    DocumentObjectExecReturn * execute();
+
+    void getDocumentObjectDeps(std::vector<DocumentObject*> & docObjs) const;
+
+    bool depsAreTouched() const;
+
+    boost::unordered_map<const App::ObjectIdentifier, const ExpressionInfo> getExpressions() const;
+
+    /* Expression validator */
+    void setValidator(ValidatorFunc f) { validator = f; }
+
+    std::string validateExpression(const App::ObjectIdentifier & path, boost::shared_ptr<const App::Expression> expr) const;
+
+    void renameExpressions(const std::map<App::ObjectIdentifier, App::ObjectIdentifier> &paths);
+
+    void renameObjectIdentifiers(const std::map<App::ObjectIdentifier, App::ObjectIdentifier> & paths);
+
+    std::set<App::ObjectIdentifier> getPaths() const;
+
+    const App::ObjectIdentifier canonicalPath(const App::ObjectIdentifier &p) const;
+
+    size_t numExpressions() const;
+
+    void slotObjectRenamed(const App::DocumentObject & obj);
+
+private:
+
+    typedef boost::adjacency_list< boost::listS, boost::vecS, boost::directedS > DiGraph;
+    typedef std::pair<int, int> Edge;
+    typedef boost::unordered_map<const App::ObjectIdentifier, ExpressionInfo> ExpressionMap;
+
+    std::vector<App::ObjectIdentifier> computeEvaluationOrder();
+
+    void buildGraphStructures(const App::ObjectIdentifier &path,
+                              const boost::shared_ptr<Expression> expression, boost::unordered_map<App::ObjectIdentifier, int> &nodes,
+                              boost::unordered_map<int, App::ObjectIdentifier> &revNodes, std::vector<Edge> &edges) const;
+
+    void buildGraph(const ExpressionMap &exprs,
+                    boost::unordered_map<int, App::ObjectIdentifier> &revNodes, DiGraph &g) const;
+
+    bool running; /**< Boolean used to avoid loops */
+
+    ExpressionMap expressions; /**< Stored expressions */
+
+    ValidatorFunc validator; /**< Valdiator functor */
+
+};
+
+}
+
+#endif // EXPRESSIONENGINE_H