QGraph: Adding the graph structure

This file was originally included by Alexis Menard <alexis.menard@nokia.com>
but now it has been fully updated to the new QGraphicsAnchorLayout needs.

Signed-off-by: Anselmo Lacerda S. de Melo <anselmo.melo@openbossa.org>
Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Signed-off-by: Jesus Sanchez-Palencia <jesus.palencia@openbossa.org>

1 files changed, 179 insertions, 0 deletions

diff --git a/src/gui/graphicsview/qgraph_p.h b/src/gui/graphicsview/qgraph_p.h
new file mode 100644
index 0000000..4a6bc8f
--- /dev/null
+++ b/src/gui/graphicsview/qgraph_p.h
@@ -0,0 +1,179 @@
+#include <QtCore/QHash>
+#include <QtCore/QQueue>
+#include <QtCore/QString>
+#include <QtCore/QDebug>
+
+#include <float.h>
+
+template <typename Vertex, typename EdgeData>
+class Graph
+{
+public:
+    Graph() {}
+
+    class iterator {
+    public:
+        iterator(Graph *graph, bool begin) : g(graph){
+            if (begin) {
+              row = g->m_graph.begin();
+              //test if the graph is empty
+              if (row != g->m_graph.end())
+              {
+                 column = (*row)->begin();
+              }
+            } else {
+               row = g->m_graph.end();
+            }
+        }
+
+        inline Vertex *operator*() {
+            return column.key();
+        }
+
+        inline bool operator==(const iterator &o) const { return !(*this != o); }
+        inline bool operator!=(const iterator &o) const {
+           if (row ==  g->m_graph.end()) {
+                return row != o.row;}
+           else {
+                return row != o.row || column != o.column;
+           }
+        }
+        inline iterator& operator=(const iterator &o) const { row = o.row; column = o.column; return *this;}
+
+        // prefix
+        iterator &operator++() {
+            if (row != g->m_graph.end()) {
+                ++column;
+                if (column == (*row)->end()) {
+                    ++row;
+                    if (row != g->m_graph.end()) {
+                        column = (*row)->begin();
+                    }
+                }
+            }
+            return *this;
+        }
+
+    private:
+        Graph *g;
+        Q_TYPENAME QHash<Vertex *, QHash<Vertex *, EdgeData *> * >::iterator row;
+        Q_TYPENAME QHash<Vertex *, EdgeData *>::iterator column;
+    };
+
+    iterator begin() {
+        return iterator(this,true);
+    }
+
+    iterator end() {
+        return iterator(this,false);
+    }
+
+    EdgeData *edgeData(Vertex *first, Vertex *second) {
+        return m_graph.value(first)->value(second);
+    }
+
+    void createEdge(Vertex *first, Vertex *second, EdgeData *data)
+    {
+        // Creates a bidirectional edge
+        createDirectedEdge(first, second, data);
+        createDirectedEdge(second, first, data);
+    }
+
+    void removeEdge(Vertex *first, Vertex *second)
+    {
+        // Creates a bidirectional edge
+        EdgeData *data = edgeData(first, second);
+        if (data) delete data;
+        removeDirectedEdge(first, second);
+        removeDirectedEdge(second, first);
+    }
+
+    QList<Vertex *> adjacentVertices(Vertex *vertex) const
+    {
+        QHash<Vertex *, EdgeData *> *row = m_graph.value(vertex);
+        QList<Vertex *> l;
+        if (row)
+            l = row->keys();
+        return l;
+    }
+
+    void setRootVertex(Vertex *vertex)
+    {
+        userVertex = vertex;
+    }
+
+    QString serializeToDot() {   // traversal
+        QString vertices;
+        QString edges;
+        QQueue<Vertex *> queue;
+        QSet<Vertex *> visited;
+        bool ok;
+        Vertex *v = firstVertex(&ok);
+        if (ok) {
+            queue.enqueue(v);
+        }
+        while (!queue.isEmpty()) {
+            Vertex *v = queue.dequeue();
+            vertices += QString::fromAscii("%1 [label=\"%2\"]\n").arg(v->toString()).arg(v->toString());
+            visited.insert(v);
+            // visit it here
+            QList<Vertex *> vertices = adjacentVertices(v);
+            for (int i = 0; i < vertices.count(); ++i) {
+                Vertex *v1 = vertices.at(i);
+                EdgeData *data = edgeData(v, v1);
+                edges+=QString::fromAscii("%1->%2 [label=\"[%3,%4]\"]\n").arg(v->toString()).arg(v1->toString()).arg(data->minSize).arg(data->maxSize);
+                if (!queue.contains(v1) && !visited.contains(v1)) {
+                    queue.enqueue(v1);
+                } else {
+                    // a cycle....
+                }
+            }
+        }
+        return QString::fromAscii("digraph anchorlayout {\nnode [shape=\"rect\"]\n%1%2}").arg(vertices).arg(edges);
+    }
+
+    Vertex *firstVertex(bool *ok)
+    {
+        if (userVertex) {
+            *ok = true;
+            return userVertex;
+        }
+
+        Vertex *v = 0;
+        *ok = false;
+        Q_TYPENAME Graph::iterator it = Graph::begin();
+        if (it != Graph::end()) {
+            v = *it;
+            *ok = true;
+        }
+        return v;
+    }
+
+protected:
+    void createDirectedEdge(Vertex *from, Vertex *to, EdgeData *data)
+    {
+        QHash<Vertex *, EdgeData *> *adjacentToFirst = m_graph.value(from);
+        if (!adjacentToFirst) {
+            adjacentToFirst = new QHash<Vertex *, EdgeData *>();
+            m_graph.insert(from, adjacentToFirst);
+        }
+        adjacentToFirst->insert(to, data);
+    }
+
+    void removeDirectedEdge(Vertex *from, Vertex *to)
+    {
+        QHash<Vertex *, EdgeData *> *adjacentToFirst = m_graph.value(from);
+        adjacentToFirst->remove(to);
+        if (adjacentToFirst->isEmpty()) {
+           //nobody point to 'from' so we can remove it from the graph
+           QHash<Vertex *, EdgeData *> *adjacentToFirst = m_graph.take(from);
+           delete adjacentToFirst;
+           delete from;
+        }
+    }
+
+private:
+    Vertex *userVertex;
+
+    QHash<Vertex *, QHash<Vertex *, EdgeData *> *> m_graph;
+};