/* This file is part of KCachegrind.
   Copyright (c) 2007-2016 Josef Weidendorfer <Josef.Weidendorfer@gmx.de>

   KCachegrind is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public
   License as published by the Free Software Foundation, version 2.

   This program 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
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
*/

/*
 * Callgraph View
 */

#include "callgraphview.h"

#include <stdlib.h>
#include <math.h>

#include <QApplication>
#include <QDebug>
#include <QFile>
#include <QFileDialog>
#include <QTemporaryFile>
#include <QTextStream>
#include <QMatrix>
#include <QPair>
#include <QPainter>
#include <QStyle>
#include <QScrollBar>
#include <QResizeEvent>
#include <QMouseEvent>
#include <QFocusEvent>
#include <QKeyEvent>
#include <QStyleOptionGraphicsItem>
#include <QContextMenuEvent>
#include <QList>
#include <QPixmap>
#include <QDesktopWidget>
#include <QProcess>
#include <QMenu>


#include "config.h"
#include "globalguiconfig.h"
#include "listutils.h"


#define DEBUG_GRAPH 0

// CallGraphView defaults

#define DEFAULT_FUNCLIMIT     .05
#define DEFAULT_CALLLIMIT     1.
#define DEFAULT_MAXCALLER     2
#define DEFAULT_MAXCALLEE     -1
#define DEFAULT_SHOWSKIPPED   false
#define DEFAULT_EXPANDCYCLES  false
#define DEFAULT_CLUSTERGROUPS false
#define DEFAULT_DETAILLEVEL   1
#define DEFAULT_LAYOUT        GraphOptions::TopDown
#define DEFAULT_ZOOMPOS       Auto


// LessThen functors as helpers for sorting of graph edges
// for keyboard navigation. Sorting is done according to
// the angle at which a edge spline goes out or in of a function.

// Sort angles of outgoing edges (edge seen as attached to the caller)
class CallerGraphEdgeLessThan
{
public:
    bool operator()(const GraphEdge* ge1, const GraphEdge* ge2) const
    {
        const CanvasEdge* ce1 = ge1->canvasEdge();
        const CanvasEdge* ce2 = ge2->canvasEdge();

        // sort invisible edges (ie. without matching CanvasEdge) in front
        if (!ce1 && !ce2) {
            // strict ordering required for std::sort
            return (ge1 < ge2);
        }
        if (!ce1) return true;
        if (!ce2) return false;

        QPolygon p1 = ce1->controlPoints();
        QPolygon p2 = ce2->controlPoints();
        QPoint d1 = p1.point(1) - p1.point(0);
        QPoint d2 = p2.point(1) - p2.point(0);
        double angle1 = atan2(double(d1.y()), double(d1.x()));
        double angle2 = atan2(double(d2.y()), double(d2.x()));

        return (angle1 < angle2);
    }
};

// Sort angles of ingoing edges (edge seen as attached to the callee)
class CalleeGraphEdgeLessThan
{
public:
    bool operator()(const GraphEdge* ge1, const GraphEdge* ge2) const
    {
        const CanvasEdge* ce1 = ge1->canvasEdge();
        const CanvasEdge* ce2 = ge2->canvasEdge();

        // sort invisible edges (ie. without matching CanvasEdge) in front
        if (!ce1) return true;
        if (!ce2) return false;

        QPolygon p1 = ce1->controlPoints();
        QPolygon p2 = ce2->controlPoints();
        QPoint d1 = p1.point(p1.count()-2) - p1.point(p1.count()-1);
        QPoint d2 = p2.point(p2.count()-2) - p2.point(p2.count()-1);
        double angle1 = atan2(double(d1.y()), double(d1.x()));
        double angle2 = atan2(double(d2.y()), double(d2.x()));

        // for ingoing edges sort according to descending angles
        return (angle2 < angle1);
    }
};



//
// GraphNode
//

GraphNode::GraphNode()
{
    _f=0;
    self = incl = 0;
    _cn = 0;

    _visible = false;
    _lastCallerIndex = _lastCalleeIndex = -1;

    _lastFromCaller = true;
}

void GraphNode::clearEdges()
{
    callees.clear();
    callers.clear();
}

CallerGraphEdgeLessThan callerGraphEdgeLessThan;
CalleeGraphEdgeLessThan calleeGraphEdgeLessThan;

void GraphNode::sortEdges()
{
    std::sort(callers.begin(), callers.end(), callerGraphEdgeLessThan);
    std::sort(callees.begin(), callees.end(), calleeGraphEdgeLessThan);
}

void GraphNode::addCallee(GraphEdge* e)
{
    if (e)
        callees.append(e);
}

void GraphNode::addCaller(GraphEdge* e)
{
    if (e)
        callers.append(e);
}

void GraphNode::addUniqueCallee(GraphEdge* e)
{
    if (e && (callees.count(e) == 0))
        callees.append(e);
}

void GraphNode::addUniqueCaller(GraphEdge* e)
{
    if (e && (callers.count(e) == 0))
        callers.append(e);
}

void GraphNode::removeEdge(GraphEdge* e)
{
    callers.removeAll(e);
    callees.removeAll(e);
}

double GraphNode::calleeCostSum()
{
    double sum = 0.0;

    foreach(GraphEdge* e, callees)
        sum += e->cost;

    return sum;
}

double GraphNode::calleeCountSum()
{
    double sum = 0.0;

    foreach(GraphEdge* e, callees)
        sum += e->count;

    return sum;
}

double GraphNode::callerCostSum()
{
    double sum = 0.0;

    foreach(GraphEdge* e, callers)
        sum += e->cost;

    return sum;
}

double GraphNode::callerCountSum()
{
    double sum = 0.0;

    foreach(GraphEdge* e, callers)
        sum += e->count;

    return sum;
}


TraceCall* GraphNode::visibleCaller()
{
    if (0)
        qDebug("GraphNode::visibleCaller %s: last %d, count %d",
               qPrintable(_f->prettyName()), _lastCallerIndex, callers.count());

    // can not use at(): index can be -1 (out of bounds), result is 0 then
    GraphEdge* e = callers.value(_lastCallerIndex);
    if (e && !e->isVisible())
        e = 0;
    if (!e) {
        double maxCost = 0.0;
        GraphEdge* maxEdge = 0;
        for(int i = 0; i<callers.size(); i++) {
            e = callers[i];
            if (e->isVisible() && (e->cost > maxCost)) {
                maxCost = e->cost;
                maxEdge = e;
                _lastCallerIndex = i;
            }
        }
        e = maxEdge;
    }
    return e ? e->call() : 0;
}

TraceCall* GraphNode::visibleCallee()
{
    if (0)
        qDebug("GraphNode::visibleCallee %s: last %d, count %d",
               qPrintable(_f->prettyName()), _lastCalleeIndex, callees.count());

    GraphEdge* e = callees.value(_lastCalleeIndex);
    if (e && !e->isVisible())
        e = 0;

    if (!e) {
        double maxCost = 0.0;
        GraphEdge* maxEdge = 0;
        for(int i = 0; i<callees.size(); i++) {
            e = callees[i];
            if (e->isVisible() && (e->cost > maxCost)) {
                maxCost = e->cost;
                maxEdge = e;
                _lastCalleeIndex = i;
            }
        }
        e = maxEdge;
    }
    return e ? e->call() : 0;
}

void GraphNode::setCallee(GraphEdge* e)
{
    _lastCalleeIndex = callees.indexOf(e);
    _lastFromCaller = false;
}

void GraphNode::setCaller(GraphEdge* e)
{
    _lastCallerIndex = callers.indexOf(e);
    _lastFromCaller = true;
}

TraceFunction* GraphNode::nextVisible()
{
    TraceCall* c;

    if (_lastFromCaller) {
        c = nextVisibleCaller();
        if (c)
            return c->called(true);
        c = nextVisibleCallee();
        if (c)
            return c->caller(true);
    } else {
        c = nextVisibleCallee();
        if (c)
            return c->caller(true);
        c = nextVisibleCaller();
        if (c)
            return c->called(true);
    }
    return 0;
}

TraceFunction* GraphNode::priorVisible()
{
    TraceCall* c;

    if (_lastFromCaller) {
        c = priorVisibleCaller();
        if (c)
            return c->called(true);
        c = priorVisibleCallee();
        if (c)
            return c->caller(true);
    } else {
        c = priorVisibleCallee();
        if (c)
            return c->caller(true);
        c = priorVisibleCaller();
        if (c)
            return c->called(true);
    }
    return 0;
}

TraceCall* GraphNode::nextVisibleCaller(GraphEdge* e)
{
    int idx = e ? callers.indexOf(e) : _lastCallerIndex;
    idx++;
    while(idx < callers.size()) {
        if (callers[idx]->isVisible()) {
            _lastCallerIndex = idx;
            return callers[idx]->call();
        }
        idx++;
    }
    return 0;
}

TraceCall* GraphNode::nextVisibleCallee(GraphEdge* e)
{
    int idx = e ? callees.indexOf(e) : _lastCalleeIndex;
    idx++;
    while(idx < callees.size()) {
        if (callees[idx]->isVisible()) {
            _lastCalleeIndex = idx;
            return callees[idx]->call();
        }
        idx++;
    }
    return 0;
}

TraceCall* GraphNode::priorVisibleCaller(GraphEdge* e)
{
    int idx = e ? callers.indexOf(e) : _lastCallerIndex;

    idx = (idx<0) ? callers.size()-1 : idx-1;
    while(idx >= 0) {
        if (callers[idx]->isVisible()) {
            _lastCallerIndex = idx;
            return callers[idx]->call();
        }
        idx--;
    }
    return 0;
}

TraceCall* GraphNode::priorVisibleCallee(GraphEdge* e)
{
    int idx = e ? callees.indexOf(e) : _lastCalleeIndex;

    idx = (idx<0) ? callees.size()-1 : idx-1;
    while(idx >= 0) {
        if (callees[idx]->isVisible()) {
            _lastCalleeIndex = idx;
            return callees[idx]->call();
        }
        idx--;
    }
    return 0;
}


//
// GraphEdge
//

GraphEdge::GraphEdge()
{
    _c=0;
    _from = _to = 0;
    _fromNode = _toNode = 0;
    cost = count = 0;
    _ce = 0;

    _visible = false;
    _lastFromCaller = true;
}

QString GraphEdge::prettyName()
{
    if (_c)
        return _c->prettyName();

    if (_from)
        return QObject::tr("Call(s) from %1").arg(_from->prettyName());

    if (_to)
        return QObject::tr("Call(s) to %1").arg(_to->prettyName());

    return QObject::tr("(unknown call)");
}

TraceFunction* GraphEdge::visibleCaller()
{
    if (_from) {
        _lastFromCaller = true;
        if (_fromNode)
            _fromNode->setCallee(this);
        return _from;
    }
    return 0;
}

TraceFunction* GraphEdge::visibleCallee()
{
    if (_to) {
        _lastFromCaller = false;
        if (_toNode)
            _toNode->setCaller(this);
        return _to;
    }
    return 0;
}

TraceCall* GraphEdge::nextVisible()
{
    TraceCall* res = 0;

    if (_lastFromCaller && _fromNode) {
        res = _fromNode->nextVisibleCallee(this);
        if (!res && _toNode)
            res = _toNode->nextVisibleCaller(this);
    } else if (_toNode) {
        res = _toNode->nextVisibleCaller(this);
        if (!res && _fromNode)
            res = _fromNode->nextVisibleCallee(this);
    }
    return res;
}

TraceCall* GraphEdge::priorVisible()
{
    TraceCall* res = 0;

    if (_lastFromCaller && _fromNode) {
        res = _fromNode->priorVisibleCallee(this);
        if (!res && _toNode)
            res = _toNode->priorVisibleCaller(this);
    } else if (_toNode) {
        res = _toNode->priorVisibleCaller(this);
        if (!res && _fromNode)
            res = _fromNode->priorVisibleCallee(this);
    }
    return res;
}



//
// GraphOptions
//

QString GraphOptions::layoutString(Layout l)
{
    if (l == Circular)
        return QStringLiteral("Circular");
    if (l == LeftRight)
        return QStringLiteral("LeftRight");
    return QStringLiteral("TopDown");
}

GraphOptions::Layout GraphOptions::layout(QString s)
{
    if (s == QStringLiteral("Circular"))
        return Circular;
    if (s == QStringLiteral("LeftRight"))
        return LeftRight;
    return TopDown;
}


//
// StorableGraphOptions
//

StorableGraphOptions::StorableGraphOptions()
{
    // default options
    _funcLimit         = DEFAULT_FUNCLIMIT;
    _callLimit         = DEFAULT_CALLLIMIT;
    _maxCallerDepth    = DEFAULT_MAXCALLER;
    _maxCalleeDepth    = DEFAULT_MAXCALLEE;
    _showSkipped       = DEFAULT_SHOWSKIPPED;
    _expandCycles      = DEFAULT_EXPANDCYCLES;
    _detailLevel       = DEFAULT_DETAILLEVEL;
    _layout            = DEFAULT_LAYOUT;
}




//
// GraphExporter
//

GraphExporter::GraphExporter()
{
    _go = this;
    _tmpFile = 0;
    _item = 0;
    reset(0, 0, 0, ProfileContext::InvalidType, QString());
}

GraphExporter::GraphExporter(TraceData* d, TraceFunction* f,
                             EventType* ct, ProfileContext::Type gt,
                             QString filename)
{
    _go = this;
    _tmpFile = 0;
    _item = 0;
    reset(d, f, ct, gt, filename);
}

GraphExporter::~GraphExporter()
{
    if (_item && _tmpFile) {
#if DEBUG_GRAPH
        _tmpFile->setAutoRemove(true);
#endif
        delete _tmpFile;
    }
}


void GraphExporter::reset(TraceData*, CostItem* i, EventType* ct,
                          ProfileContext::Type gt, QString filename)
{
    _graphCreated = false;
    _nodeMap.clear();
    _edgeMap.clear();

    if (_item && _tmpFile) {
        _tmpFile->setAutoRemove(true);
        delete _tmpFile;
    }

    if (i) {
        switch (i->type()) {
        case ProfileContext::Function:
        case ProfileContext::FunctionCycle:
        case ProfileContext::Call:
            break;
        default:
            i = 0;
        }
    }

    _item = i;
    _eventType = ct;
    _groupType = gt;
    if (!i)
        return;

    if (filename.isEmpty()) {
        _tmpFile = new QTemporaryFile();
        //_tmpFile->setSuffix(".dot");
        _tmpFile->setAutoRemove(false);
        _tmpFile->open();
        _dotName = _tmpFile->fileName();
        _useBox = true;
    } else {
        _tmpFile = 0;
        _dotName = filename;
        _useBox = false;
    }
}



void GraphExporter::setGraphOptions(GraphOptions* go)
{
    if (go == 0)
        go = this;
    _go = go;
}

void GraphExporter::createGraph()
{
    if (!_item)
        return;
    if (_graphCreated)
        return;
    _graphCreated = true;

    if ((_item->type() == ProfileContext::Function) ||(_item->type()
                                                       == ProfileContext::FunctionCycle)) {
        TraceFunction* f = (TraceFunction*) _item;

        double incl = f->inclusive()->subCost(_eventType);
        _realFuncLimit = incl * _go->funcLimit();
        _realCallLimit = _realFuncLimit * _go->callLimit();

        buildGraph(f, 0, true, 1.0); // down to callees

        // set costs of function back to 0, as it will be added again
        GraphNode& n = _nodeMap[f];
        n.self = n.incl = 0.0;

        buildGraph(f, 0, false, 1.0); // up to callers
    } else {
        TraceCall* c = (TraceCall*) _item;

        double incl = c->subCost(_eventType);
        _realFuncLimit = incl * _go->funcLimit();
        _realCallLimit = _realFuncLimit * _go->callLimit();

        // create edge
        TraceFunction *caller, *called;
        caller = c->caller(false);
        called = c->called(false);
        QPair<TraceFunction*,TraceFunction*> p(caller, called);
        GraphEdge& e = _edgeMap[p];
        e.setCall(c);
        e.setCaller(p.first);
        e.setCallee(p.second);
        e.cost = c->subCost(_eventType);
        e.count = c->callCount();

        SubCost s = called->inclusive()->subCost(_eventType);
        buildGraph(called, 0, true, e.cost / s); // down to callees
        s = caller->inclusive()->subCost(_eventType);
        buildGraph(caller, 0, false, e.cost / s); // up to callers
    }
}


void GraphExporter::writeDot(QIODevice* device)
{
    if (!_item)
        return;

    QFile* file = 0;
    QTextStream* stream = 0;

    if (device)
        stream = new QTextStream(device);
    else {
        if (_tmpFile)
            stream = new QTextStream(_tmpFile);
        else {
            file = new QFile(_dotName);
            if ( !file->open(QIODevice::WriteOnly ) ) {
                qDebug() << "Can not write dot file '"<< _dotName << "'";
                delete file;
                return;
            }
            stream = new QTextStream(file);
        }
    }

    if (!_graphCreated)
        createGraph();

    /* Generate dot format...
     * When used for the CallGraphView (in contrast to "Export Callgraph..."),
     * the labels are only dummy placeholders to reserve space for our own
     * drawings.
     */

    *stream << "digraph \"callgraph\" {\n";

    if (_go->layout() == LeftRight) {
        *stream << QStringLiteral("  rankdir=LR;\n");
    } else if (_go->layout() == Circular) {
        TraceFunction *f = 0;
        switch (_item->type()) {
        case ProfileContext::Function:
        case ProfileContext::FunctionCycle:
            f = (TraceFunction*) _item;
            break;
        case ProfileContext::Call:
            f = ((TraceCall*)_item)->caller(true);
            break;
        default:
            break;
        }
        if (f)
            *stream << QStringLiteral("  center=F%1;\n").arg((qptrdiff)f, 0, 16);
        *stream << QStringLiteral("  overlap=false;\n  splines=true;\n");
    }

    // for clustering
    QMap<TraceCostItem*,QList<GraphNode*> > nLists;

    GraphNodeMap::Iterator nit;
    for (nit = _nodeMap.begin(); nit != _nodeMap.end(); ++nit ) {
        GraphNode& n = *nit;

        if (n.incl <= _realFuncLimit)
            continue;

        // for clustering: get cost item group of function
        TraceCostItem* g;
        TraceFunction* f = n.function();
        switch (_groupType) {
        case ProfileContext::Object:
            g = f->object();
            break;
        case ProfileContext::Class:
            g = f->cls();
            break;
        case ProfileContext::File:
            g = f->file();
            break;
        case ProfileContext::FunctionCycle:
            g = f->cycle();
            break;
        default:
            g = 0;
            break;
        }
        nLists[g].append(&n);
    }

    QMap<TraceCostItem*,QList<GraphNode*> >::Iterator lit;
    int cluster = 0;
    for (lit = nLists.begin(); lit != nLists.end(); ++lit, cluster++) {
        QList<GraphNode*>& l = lit.value();
        TraceCostItem* i = lit.key();

        if (_go->clusterGroups() && i) {
            QString iabr = GlobalConfig::shortenSymbol(i->prettyName());
            // escape quotation marks in symbols to avoid invalid dot syntax
            iabr.replace("\"", "\\\"");
            *stream << QStringLiteral("subgraph \"cluster%1\" { label=\"%2\";\n")
                       .arg(cluster).arg(iabr);
        }

        foreach(GraphNode* np, l) {
            TraceFunction* f = np->function();

            QString abr = GlobalConfig::shortenSymbol(f->prettyName());
            // escape quotation marks to avoid invalid dot syntax
            abr.replace("\"", "\\\"");
            *stream << QStringLiteral("  F%1 [").arg((qptrdiff)f, 0, 16);
            if (_useBox) {
                // we want a minimal size for cost display
                if ((int)abr.length() < 8) abr = abr + QString(8 - abr.length(),'_');

                // make label 3 lines for CallGraphView
                *stream << QStringLiteral("shape=box,label=\"** %1 **\\n**\\n%2\"];\n")
                           .arg(abr)
                           .arg(SubCost(np->incl).pretty());
            } else
                *stream << QStringLiteral("label=\"%1\\n%2\"];\n")
                           .arg(abr)
                           .arg(SubCost(np->incl).pretty());
        }

        if (_go->clusterGroups() && i)
            *stream << QStringLiteral("}\n");
    }

    GraphEdgeMap::Iterator eit;
    for (eit = _edgeMap.begin(); eit != _edgeMap.end(); ++eit ) {
        GraphEdge& e = *eit;

        if (e.cost < _realCallLimit)
            continue;
        if (!_go->expandCycles()) {
            // do not show inner cycle calls
            if (e.call()->inCycle()>0)
                continue;
        }

        GraphNode& from = _nodeMap[e.from()];
        GraphNode& to = _nodeMap[e.to()];

        e.setCallerNode(&from);
        e.setCalleeNode(&to);

        if ((from.incl <= _realFuncLimit) ||(to.incl <= _realFuncLimit))
            continue;

        // remove dumped edges from n.callers/n.callees
        from.removeEdge(&e);
        to.removeEdge(&e);

        *stream << QStringLiteral("  F%1 -> F%2 [weight=%3")
                   .arg((qptrdiff)e.from(), 0, 16)
                   .arg((qptrdiff)e.to(), 0, 16)
                   .arg((long)log(log(e.cost)));

        if (_go->detailLevel() ==1) {
            *stream << QStringLiteral(",label=\"%1 (%2x)\"")
                       .arg(SubCost(e.cost).pretty())
                       .arg(SubCost(e.count).pretty());
        }
        else if (_go->detailLevel() ==2)
            *stream << QStringLiteral(",label=\"%3\\n%4 x\"")
                       .arg(SubCost(e.cost).pretty())
                       .arg(SubCost(e.count).pretty());

        *stream << QStringLiteral("];\n");
    }

    if (_go->showSkipped()) {

        // Create sum-edges for skipped edges
        GraphEdge* e;
        double costSum, countSum;
        for (nit = _nodeMap.begin(); nit != _nodeMap.end(); ++nit ) {
            GraphNode& n = *nit;
            if (n.incl <= _realFuncLimit)
                continue;

            // add edge for all skipped callers if cost sum is high enough
            costSum = n.callerCostSum();
            countSum = n.callerCountSum();
            if (costSum > _realCallLimit) {

                QPair<TraceFunction*,TraceFunction*> p(0, n.function());
                e = &(_edgeMap[p]);
                e->setCallee(p.second);
                e->cost = costSum;
                e->count = countSum;

                *stream << QStringLiteral("  R%1 [shape=point,label=\"\"];\n")
                           .arg((qptrdiff)n.function(), 0, 16);
                *stream << QStringLiteral("  R%1 -> F%2 [label=\"%3\\n%4 x\",weight=%5];\n")
                           .arg((qptrdiff)n.function(), 0, 16)
                           .arg((qptrdiff)n.function(), 0, 16)
                           .arg(SubCost(costSum).pretty())
                           .arg(SubCost(countSum).pretty())
                           .arg((int)log(costSum));
            }

            // add edge for all skipped callees if cost sum is high enough
            costSum = n.calleeCostSum();
            countSum = n.calleeCountSum();
            if (costSum > _realCallLimit) {

                QPair<TraceFunction*,TraceFunction*> p(n.function(), 0);
                e = &(_edgeMap[p]);
                e->setCaller(p.first);
                e->cost = costSum;
                e->count = countSum;

                *stream << QStringLiteral("  S%1 [shape=point,label=\"\"];\n")
                           .arg((qptrdiff)n.function(), 0, 16);
                *stream << QStringLiteral("  F%1 -> S%2 [label=\"%3\\n%4 x\",weight=%5];\n")
                           .arg((qptrdiff)n.function(), 0, 16)
                           .arg((qptrdiff)n.function(), 0, 16)
                           .arg(SubCost(costSum).pretty())
                           .arg(SubCost(countSum).pretty())
                           .arg((int)log(costSum));
            }
        }
    }

    // clear edges here completely.
    // Visible edges are inserted again on parsing in CallGraphView::refresh
    for (nit = _nodeMap.begin(); nit != _nodeMap.end(); ++nit ) {
        GraphNode& n = *nit;
        n.clearEdges();
    }

    *stream << "}\n";

    if (!device) {
        if (_tmpFile) {
            stream->flush();
            _tmpFile->seek(0);
        } else {
            file->close();
            delete file;
        }
    }
    delete stream;
}

void GraphExporter::sortEdges()
{
    GraphNodeMap::Iterator nit;
    for (nit = _nodeMap.begin(); nit != _nodeMap.end(); ++nit ) {
        GraphNode& n = *nit;
        n.sortEdges();
    }
}

TraceFunction* GraphExporter::toFunc(QString s)
{
    if (s[0] != 'F')
        return 0;
    bool ok;
    TraceFunction* f = (TraceFunction*) s.midRef(1).toULongLong(&ok, 16);
    if (!ok)
        return 0;

    return f;
}

GraphNode* GraphExporter::node(TraceFunction* f)
{
    if (!f)
        return 0;

    GraphNodeMap::Iterator it = _nodeMap.find(f);
    if (it == _nodeMap.end())
        return 0;

    return &(*it);
}

GraphEdge* GraphExporter::edge(TraceFunction* f1, TraceFunction* f2)
{
    GraphEdgeMap::Iterator it = _edgeMap.find(qMakePair(f1, f2));
    if (it == _edgeMap.end())
        return 0;

    return &(*it);
}

/**
 * We do a DFS and do not stop on already visited nodes/edges,
 * but add up costs. We only stop if limits/max depth is reached.
 *
 * For a node/edge, it can happen that the first time visited the
 * cost will below the limit, so the search is stopped.
 * If on a further visit of the node/edge the limit is reached,
 * we use the whole node/edge cost and continue search.
 */
void GraphExporter::buildGraph(TraceFunction* f, int depth, bool toCallees,
                               double factor)
{
#if DEBUG_GRAPH
    qDebug() << "buildGraph(" << f->prettyName() << "," << d << "," << factor
             << ") [to " << (toCallees ? "Callees":"Callers") << "]";
#endif

    double oldIncl = 0.0;
    GraphNode& n = _nodeMap[f];
    if (n.function() == 0) {
        n.setFunction(f);
    } else
        oldIncl = n.incl;

    double incl = f->inclusive()->subCost(_eventType) * factor;
    n.incl += incl;
    n.self += f->subCost(_eventType) * factor;
    if (0)
        qDebug("  Added Incl. %f, now %f", incl, n.incl);

    // A negative depth limit means "unlimited"
    int maxDepth = toCallees ? _go->maxCalleeDepth()
                             : _go->maxCallerDepth();
    // Never go beyound a depth of 100
    if ((maxDepth < 0) || (maxDepth>100)) maxDepth = 100;
    if (depth >= maxDepth) {
        if (0)
            qDebug("  Cutoff, max depth reached");
        return;
    }

    // if we just reached the limit by summing, do a DFS
    // from here with full incl. cost because of previous cutoffs
    if ((n.incl >= _realFuncLimit) && (oldIncl < _realFuncLimit))
        incl = n.incl;

    if (f->cycle()) {
        // for cycles members, we never stop on first visit, but always on 2nd
        // note: a 2nd visit never should happen, as we do not follow inner-cycle
        //       calls
        if (oldIncl > 0.0) {
            if (0)
                qDebug("  Cutoff, 2nd visit to Cycle Member");
            // and takeback cost addition, as it is added twice
            n.incl = oldIncl;
            n.self -= f->subCost(_eventType) * factor;
            return;
        }
    } else if (incl <= _realFuncLimit) {
        if (0)
            qDebug("  Cutoff, below limit");
        return;
    }

    TraceFunction* f2;

    // on entering a cycle, only go the FunctionCycle
    TraceCallList l = toCallees ? f->callings(false) : f->callers(false);

    foreach(TraceCall* call, l) {

        f2 = toCallees ? call->called(false) : call->caller(false);

        double count = call->callCount() * factor;
        double cost = call->subCost(_eventType) * factor;

        // ignore function calls with absolute cost < 3 per call
        // No: This would skip a lot of functions e.g. with L2 cache misses
        // if (count>0.0 && (cost/count < 3)) continue;

        double oldCost = 0.0;
        QPair<TraceFunction*,TraceFunction*> p(toCallees ? f : f2,
                                               toCallees ? f2 : f);
        GraphEdge& e = _edgeMap[p];
        if (e.call() == 0) {
            e.setCall(call);
            e.setCaller(p.first);
            e.setCallee(p.second);
        } else
            oldCost = e.cost;

        e.cost += cost;
        e.count += count;
        if (0)
            qDebug("  Edge to %s, added cost %f, now %f",
                   qPrintable(f2->prettyName()), cost, e.cost);

        // if this call goes into a FunctionCycle, we also show the real call
        if (f2->cycle() == f2) {
            TraceFunction* realF;
            realF = toCallees ? call->called(true) : call->caller(true);
            QPair<TraceFunction*,TraceFunction*>
                    realP(toCallees ? f : realF, toCallees ? realF : f);
            GraphEdge& e = _edgeMap[realP];
            if (e.call() == 0) {
                e.setCall(call);
                e.setCaller(realP.first);
                e.setCallee(realP.second);
            }
            e.cost += cost;
            e.count += count;
        }

        // - do not do a DFS on calls in recursion/cycle
        if (call->inCycle()>0)
            continue;
        if (call->isRecursion())
            continue;

        if (toCallees)
            n.addUniqueCallee(&e);
        else
            n.addUniqueCaller(&e);

        // if we just reached the call limit (=func limit by summing, do a DFS
        // from here with full incl. cost because of previous cutoffs
        if ((e.cost >= _realCallLimit) && (oldCost < _realCallLimit))
            cost = e.cost;
        if ((cost <= 0) || (cost <= _realCallLimit)) {
            if (0)
                qDebug("  Edge Cutoff, limit not reached");
            continue;
        }

        SubCost s;
        if (call->inCycle())
            s = f2->cycle()->inclusive()->subCost(_eventType);
        else
            s = f2->inclusive()->subCost(_eventType);
        SubCost v = call->subCost(_eventType);

        // Never recurse if s or v is 0 (can happen with bogus input)
        if ((v == 0) || (s== 0)) continue;

        buildGraph(f2, depth+1, toCallees, factor * v / s);
    }
}

//
// PannerView
//
PanningView::PanningView(QWidget * parent)
    : QGraphicsView(parent)
{
    _movingZoomRect = false;

    // FIXME: Why does this not work?
    viewport()->setFocusPolicy(Qt::NoFocus);
}

void PanningView::setZoomRect(const QRectF& r)
{
    _zoomRect = r;
    viewport()->update();
}

void PanningView::drawForeground(QPainter * p, const QRectF&)
{
    if (!_zoomRect.isValid())
        return;

    QColor red(Qt::red);
    QPen pen(red.dark());
    pen.setWidthF(2.0 / matrix().m11());
    p->setPen(pen);

    QColor c(red.dark());
    c.setAlphaF(0.05);
    p->setBrush(QBrush(c));

    p->drawRect(QRectF(_zoomRect.x(), _zoomRect.y(),
                       _zoomRect.width()-1, _zoomRect.height()-1));
}

void PanningView::mousePressEvent(QMouseEvent* e)
{
    QPointF sPos = mapToScene(e->pos());

    if (_zoomRect.isValid()) {
        if (!_zoomRect.contains(sPos))
            emit zoomRectMoved(sPos.x() - _zoomRect.center().x(),
                               sPos.y() - _zoomRect.center().y());

        _movingZoomRect = true;
        _lastPos = sPos;
    }
}

void PanningView::mouseMoveEvent(QMouseEvent* e)
{
    QPointF sPos = mapToScene(e->pos());
    if (_movingZoomRect) {
        emit zoomRectMoved(sPos.x() - _lastPos.x(),
                           sPos.y() - _lastPos.y());
        _lastPos = sPos;
    }
}

void PanningView::mouseReleaseEvent(QMouseEvent*)
{
    _movingZoomRect = false;
    emit zoomRectMoveFinished();
}





//
// CanvasNode
//

CanvasNode::CanvasNode(CallGraphView* v, GraphNode* n, int x, int y, int w,
                       int h) :
    QGraphicsRectItem(QRect(x, y, w, h)), _node(n), _view(v)
{
    setPosition(0, DrawParams::TopCenter);
    setPosition(1, DrawParams::BottomCenter);

    updateGroup();

    if (!_node || !_view)
        return;

    if (_node->function())
        setText(0, _node->function()->prettyName());

    ProfileCostArray* totalCost;
    if (GlobalConfig::showExpanded()) {
        if (_view->activeFunction()) {
            if (_view->activeFunction()->cycle())
                totalCost = _view->activeFunction()->cycle()->inclusive();
            else
                totalCost = _view->activeFunction()->inclusive();
        } else
            totalCost = (ProfileCostArray*) _view->activeItem();
    } else
        totalCost = ((TraceItemView*)_view)->data();
    double total = totalCost->subCost(_view->eventType());
    double inclP = 100.0 * n->incl/ total;
    if (GlobalConfig::showPercentage())
        setText(1, QStringLiteral("%1 %")
                .arg(inclP, 0, 'f', GlobalConfig::percentPrecision()));
    else
        setText(1, SubCost(n->incl).pretty());
    setPixmap(1, percentagePixmap(25, 10, (int)(inclP+.5), Qt::blue, true));

    setToolTip(QStringLiteral("%1 (%2)").arg(text(0)).arg(text(1)));
}

void CanvasNode::setSelected(bool s)
{
    StoredDrawParams::setSelected(s);
    update();
}

void CanvasNode::updateGroup()
{
    if (!_view || !_node)
        return;

    QColor c = GlobalGUIConfig::functionColor(_view->groupType(),
                                              _node->function());
    setBackColor(c);
    update();
}

void CanvasNode::paint(QPainter* p,
                       const QStyleOptionGraphicsItem* option,
                       QWidget*)
{
    QRect r = rect().toRect(), origRect = r;

    r.setRect(r.x()+1, r.y()+1, r.width()-2, r.height()-2);

    RectDrawing d(r);
    d.drawBack(p, this);
    r.setRect(r.x()+2, r.y()+2, r.width()-4, r.height()-4);

#if 0
    if (StoredDrawParams::selected() && _view->hasFocus()) {
        _view->style().drawPrimitive( QStyle::PE_FocusRect, &p, r,
                                      _view->colorGroup());
    }
#endif

    // draw afterwards to always get a frame even when zoomed
    p->setPen(StoredDrawParams::selected() ? Qt::red : Qt::black);
    p->drawRect(QRect(origRect.x(), origRect.y(), origRect.width()-1,
                      origRect.height()-1));

#if QT_VERSION >= 0x040600
    if (option->levelOfDetailFromTransform(p->transform()) < .5)
        return;
#else
    if (option->levelOfDetail < .5)
        return;
#endif

    d.setRect(r);
    d.drawField(p, 0, this);
    d.drawField(p, 1, this);
}


//
// CanvasEdgeLabel
//

CanvasEdgeLabel::CanvasEdgeLabel(CallGraphView* v, CanvasEdge* ce, int x,
                                 int y, int w, int h) :
    QGraphicsRectItem(QRect(x, y, w, h)), _ce(ce), _view(v), _percentage(0.0)
{
    GraphEdge* e = ce->edge();
    if (!e)
        return;

    setPosition(1, DrawParams::BottomCenter);
    ProfileCostArray* totalCost;
    if (GlobalConfig::showExpanded()) {
        if (_view->activeFunction()) {
            if (_view->activeFunction()->cycle())
                totalCost = _view->activeFunction()->cycle()->inclusive();
            else
                totalCost = _view->activeFunction()->inclusive();
        } else
            totalCost = (ProfileCostArray*) _view->activeItem();
    } else
        totalCost = ((TraceItemView*)_view)->data();
    double total = totalCost->subCost(_view->eventType());
    double inclP = 100.0 * e->cost/ total;
    if (GlobalConfig::showPercentage())
        setText(1, QStringLiteral("%1 %")
                .arg(inclP, 0, 'f', GlobalConfig::percentPrecision()));
    else
        setText(1, SubCost(e->cost).pretty());

    int pixPos = 1;
    if (((TraceItemView*)_view)->data()->maxCallCount() > 0) {
        setPosition(0, DrawParams::TopCenter);
        SubCost count((e->count < 1.0) ? 1.0 : e->count);
        setText(0, QStringLiteral("%1 x").arg(count.pretty()));
        pixPos = 0;
        setToolTip(QStringLiteral("%1 (%2)").arg(text(0)).arg(text(1)));
    }
    setPixmap(pixPos, percentagePixmap(25, 10, (int)(inclP+.5), Qt::blue, true));

    _percentage = inclP;
    if (_percentage > 100.0) _percentage = 100.0;

    if (e->call() && (e->call()->isRecursion() || e->call()->inCycle())) {
        QFontMetrics fm(font());
        QPixmap p = QIcon::fromTheme(QStringLiteral("edit-undo")).pixmap(fm.height());
        setPixmap(pixPos, p); // replace percentage pixmap
    }
}

void CanvasEdgeLabel::paint(QPainter* p,
                            const QStyleOptionGraphicsItem* option, QWidget*)
{
    // draw nothing in PanningView
#if QT_VERSION >= 0x040600
    if (option->levelOfDetailFromTransform(p->transform()) < .5)
        return;
#else
    if (option->levelOfDetail < .5)
        return;
#endif

    QRect r = rect().toRect();

    RectDrawing d(r);
    d.drawField(p, 0, this);
    d.drawField(p, 1, this);
}



//
// CanvasEdgeArrow

CanvasEdgeArrow::CanvasEdgeArrow(CanvasEdge* ce)
    : _ce(ce)
{}

void CanvasEdgeArrow::paint(QPainter* p,
                            const QStyleOptionGraphicsItem *, QWidget *)
{
    p->setRenderHint(QPainter::Antialiasing);
    p->setBrush(_ce->isSelected() ? Qt::red : Qt::black);
    p->drawPolygon(polygon(), Qt::OddEvenFill);
}


//
// CanvasEdge
//

CanvasEdge::CanvasEdge(GraphEdge* e) :
    _edge(e)
{
    _label = 0;
    _arrow = 0;
    _thickness = 0;

    setFlag(QGraphicsItem::ItemIsSelectable);
}

void CanvasEdge::setLabel(CanvasEdgeLabel* l)
{
    _label = l;

    if (l) {
        QString tip = QStringLiteral("%1 (%2)").arg(l->text(0)).arg(l->text(1));

        setToolTip(tip);
        if (_arrow) _arrow->setToolTip(tip);

        _thickness = log(l->percentage());
        if (_thickness < .9) _thickness = .9;
    }
}

void CanvasEdge::setArrow(CanvasEdgeArrow* a)
{
    _arrow = a;

    if (a && _label) a->setToolTip(QStringLiteral("%1 (%2)")
                                   .arg(_label->text(0)).arg(_label->text(1)));
}

void CanvasEdge::setSelected(bool s)
{
    QGraphicsItem::setSelected(s);
    update();
}

void CanvasEdge::setControlPoints(const QPolygon& pa)
{
    _points = pa;

    QPainterPath path;
    path.moveTo(pa[0]);
    for (int i = 1; i < pa.size(); i += 3)
        path.cubicTo(pa[i], pa[(i + 1) % pa.size()], pa[(i + 2) % pa.size()]);

    setPath(path);
}


void CanvasEdge::paint(QPainter* p,
                       const QStyleOptionGraphicsItem* option, QWidget*)
{
    p->setRenderHint(QPainter::Antialiasing);

    qreal levelOfDetail;
#if QT_VERSION >= 0x040600
    levelOfDetail = option->levelOfDetailFromTransform(p->transform());
#else
    levelOfDetail = option->levelOfDetail;
#endif

    QPen mypen = pen();
    mypen.setWidthF(1.0/levelOfDetail * _thickness);
    p->setPen(mypen);
    p->drawPath(path());

    if (isSelected()) {
        mypen.setColor(Qt::red);
        mypen.setWidthF(1.0/levelOfDetail * _thickness/2.0);
        p->setPen(mypen);
        p->drawPath(path());
    }
}


//
// CanvasFrame
//

QPixmap* CanvasFrame::_p = 0;

CanvasFrame::CanvasFrame(CanvasNode* n)
{
    if (!_p) {

        int d = 5;
        float v1 = 130.0f, v2 = 10.0f, v = v1, f = 1.03f;

        // calculate pix size
        QRect r(0, 0, 30, 30);
        while (v>v2) {
            r.setRect(r.x()-d, r.y()-d, r.width()+2*d, r.height()+2*d);
            v /= f;
        }

        _p = new QPixmap(r.size());
        _p->fill(Qt::white);
        QPainter p(_p);
        p.setPen(Qt::NoPen);

        r.translate(-r.x(), -r.y());

        while (v<v1) {
            v *= f;
            p.setBrush(QColor(265-(int)v, 265-(int)v, 265-(int)v));

            p.drawRect(QRect(r.x(), r.y(), r.width(), d));
            p.drawRect(QRect(r.x(), r.bottom()-d, r.width(), d));
            p.drawRect(QRect(r.x(), r.y()+d, d, r.height()-2*d));
            p.drawRect(QRect(r.right()-d, r.y()+d, d, r.height()-2*d));

            r.setRect(r.x()+d, r.y()+d, r.width()-2*d, r.height()-2*d);
        }
    }

    setRect(QRectF(n->rect().center().x() - _p->width()/2,
                   n->rect().center().y() - _p->height()/2, _p->width(), _p->height()) );
}


void CanvasFrame::paint(QPainter* p,
                        const QStyleOptionGraphicsItem* option, QWidget*)
{
    qreal levelOfDetail;
#if QT_VERSION >= 0x040600
    levelOfDetail = option->levelOfDetailFromTransform(p->transform());
#else
    levelOfDetail = option->levelOfDetail;
#endif
    if (levelOfDetail < .5) {
        QRadialGradient g(rect().center(), rect().width()/3);
        g.setColorAt(0.0, Qt::gray);
        g.setColorAt(1.0, Qt::white);

        p->setBrush(QBrush(g));
        p->setPen(Qt::NoPen);
        p->drawRect(rect());
        return;
    }

    p->drawPixmap(int( rect().x()),int( rect().y()), *_p );
}



//
// CallGraphView
//
CallGraphView::CallGraphView(TraceItemView* parentView, QWidget* parent,
                             const QString& name) :
    QGraphicsView(parent), TraceItemView(parentView)
{
    setObjectName(name);
    _zoomPosition = DEFAULT_ZOOMPOS;
    _lastAutoPosition = TopLeft;

    _scene = 0;
    _xMargin = _yMargin = 0;
    _panningView = new PanningView(this);
    _panningZoom = 1;
    _selectedNode = 0;
    _selectedEdge = 0;
    _isMoving = false;

    _exporter.setGraphOptions(this);

    _panningView->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    _panningView->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    _panningView->raise();
    _panningView->hide();

    setFocusPolicy(Qt::StrongFocus);
    setAttribute(Qt::WA_NoSystemBackground, true);

    connect(_panningView, &PanningView::zoomRectMoved, this, &CallGraphView::zoomRectMoved);
    connect(_panningView, &PanningView::zoomRectMoveFinished, this, &CallGraphView::zoomRectMoveFinished);

    this->setWhatsThis(whatsThis() );

    // tooltips...
    //_tip = new CallGraphTip(this);

    _renderProcess = 0;
    _prevSelectedNode = 0;
    connect(&_renderTimer, &QTimer::timeout,
            this, &CallGraphView::showRenderWarning);
}

CallGraphView::~CallGraphView()
{
    clear();
    delete _panningView;
}

QString CallGraphView::whatsThis() const
{
    return tr("<b>Call Graph around active Function</b>"
              "<p>Depending on configuration, this view shows "
              "the call graph environment of the active function. "
              "Note: the shown cost is <b>only</b> the cost which is "
              "spent while the active function was actually running; "
              "i.e. the cost shown for main() - if it is visible - should "
              "be the same as the cost of the active function, as that is "
              "the part of inclusive cost of main() spent while the active "
              "function was running.</p>"
              "<p>For cycles, blue call arrows indicate that this is an "
              "artificial call added for correct drawing which "
              "actually never happened.</p>"
              "<p>If the graph is larger than the widget area, an overview "
              "panner is shown in one edge. "
              "There are similar visualization options to the "
              "Call Treemap; the selected function is highlighted.</p>");
}

void CallGraphView::updateSizes(QSize s)
{
    if (!_scene)
        return;

    if (s == QSize(0, 0))
        s = size();

    // the part of the scene that should be visible
    int cWidth = (int)_scene->width() - 2*_xMargin + 100;
    int cHeight = (int)_scene->height() - 2*_yMargin + 100;

    // hide birds eye view if no overview needed
    if (!_data || !_activeItem ||
        ((cWidth < s.width()) && (cHeight < s.height())) ) {
        _panningView->hide();
        return;
    }

    // first, assume use of 1/3 of width/height (possible larger)
    double zoom = .33 * s.width() / cWidth;
    if (zoom * cHeight < .33 * s.height())
        zoom = .33 * s.height() / cHeight;

    // fit to widget size
    if (cWidth * zoom > s.width())
        zoom = s.width() / (double)cWidth;
    if (cHeight * zoom > s.height())
        zoom = s.height() / (double)cHeight;

    // scale to never use full height/width
    zoom = zoom * 3/4;

    // at most a zoom of 1/3
    if (zoom > .33)
        zoom = .33;

    if (zoom != _panningZoom) {
        _panningZoom = zoom;
        if (0)
            qDebug("Canvas Size: %fx%f, Content: %dx%d, Zoom: %f",
                   _scene->width(), _scene->height(), cWidth, cHeight, zoom);

        QMatrix m;
        _panningView->setMatrix(m.scale(zoom, zoom));

        // make it a little bigger to compensate for widget frame
        _panningView->resize(int(cWidth * zoom) + 4, int(cHeight * zoom) + 4);

        // update ZoomRect in panningView
        scrollContentsBy(0, 0);
    }

    _panningView->centerOn(_scene->width()/2, _scene->height()/2);

    int cvW = _panningView->width();
    int cvH = _panningView->height();
    int x = width()- cvW - verticalScrollBar()->width() -2;
    int y = height()-cvH - horizontalScrollBar()->height() -2;
    QPoint oldZoomPos = _panningView->pos();
    QPoint newZoomPos = QPoint(0, 0);
    ZoomPosition zp = _zoomPosition;
    if (zp == Auto) {
        int tlCols = items(QRect(0,0, cvW,cvH)).count();
        int trCols = items(QRect(x,0, cvW,cvH)).count();
        int blCols = items(QRect(0,y, cvW,cvH)).count();
        int brCols = items(QRect(x,y, cvW,cvH)).count();
        int minCols = tlCols;

        zp = _lastAutoPosition;
        switch (zp) {
        case TopRight:
            minCols = trCols;
            break;
        case BottomLeft:
            minCols = blCols;
            break;
        case BottomRight:
            minCols = brCols;
            break;
        default:
        case TopLeft:
            minCols = tlCols;
            break;
        }

        if (minCols > tlCols) {
            minCols = tlCols;
            zp = TopLeft;
        }
        if (minCols > trCols) {
            minCols = trCols;
            zp = TopRight;
        }
        if (minCols > blCols) {
            minCols = blCols;
            zp = BottomLeft;
        }
        if (minCols > brCols) {
            minCols = brCols;
            zp = BottomRight;
        }

        _lastAutoPosition = zp;
    }

    switch (zp) {
    case TopLeft:
        newZoomPos = QPoint(0, 0);
        break;
    case TopRight:
        newZoomPos = QPoint(x, 0);
        break;
    case BottomLeft:
        newZoomPos = QPoint(0, y);
        break;
    case BottomRight:
        newZoomPos = QPoint(x, y);
        break;
    default:
        break;
    }

    if (newZoomPos != oldZoomPos)
        _panningView->move(newZoomPos);

    if (zp == Hide)
        _panningView->hide();
    else
        _panningView->show();
}

void CallGraphView::focusInEvent(QFocusEvent*)
{
    if (!_scene) return;

    if (_selectedNode && _selectedNode->canvasNode()) {
        _selectedNode->canvasNode()->setSelected(true); // requests item update
        _scene->update();
    }
}

void CallGraphView::focusOutEvent(QFocusEvent* e)
{
    // trigger updates as in focusInEvent
    focusInEvent(e);
}

void CallGraphView::keyPressEvent(QKeyEvent* e)
{
    if (!_scene) {
        e->ignore();
        return;
    }

    if ((e->key() == Qt::Key_Return) ||(e->key() == Qt::Key_Space)) {
        if (_selectedNode)
            activated(_selectedNode->function());
        else if (_selectedEdge && _selectedEdge->call())
            activated(_selectedEdge->call());
        return;
    }

    // move selected node/edge
    if (!(e->modifiers() & (Qt::ShiftModifier | Qt::ControlModifier))
        &&(_selectedNode || _selectedEdge)&&((e->key() == Qt::Key_Up)
                                             ||(e->key() == Qt::Key_Down)||(e->key() == Qt::Key_Left)||(e->key()
                                                                                                        == Qt::Key_Right))) {

        TraceFunction* f = 0;
        TraceCall* c = 0;

        // rotate arrow key meaning for LeftRight layout
        int key = e->key();
        if (_layout == LeftRight) {
            switch (key) {
            case Qt::Key_Up:
                key = Qt::Key_Left;
                break;
            case Qt::Key_Down:
                key = Qt::Key_Right;
                break;
            case Qt::Key_Left:
                key = Qt::Key_Up;
                break;
            case Qt::Key_Right:
                key = Qt::Key_Down;
                break;
            default:
                break;
            }
        }

        if (_selectedNode) {
            if (key == Qt::Key_Up)
                c = _selectedNode->visibleCaller();
            if (key == Qt::Key_Down)
                c = _selectedNode->visibleCallee();
            if (key == Qt::Key_Right)
                f = _selectedNode->nextVisible();
            if (key == Qt::Key_Left)
                f = _selectedNode->priorVisible();
        } else if (_selectedEdge) {
            if (key == Qt::Key_Up)
                f = _selectedEdge->visibleCaller();
            if (key == Qt::Key_Down)
                f = _selectedEdge->visibleCallee();
            if (key == Qt::Key_Right)
                c = _selectedEdge->nextVisible();
            if (key == Qt::Key_Left)
                c = _selectedEdge->priorVisible();
        }

        if (c)
            selected(c);
        if (f)
            selected(f);
        return;
    }

    // move canvas...
    QPointF center = mapToScene(viewport()->rect().center());
    if (e->key() == Qt::Key_Home)
        centerOn(center + QPointF(-_scene->width(), 0));
    else if (e->key() == Qt::Key_End)
        centerOn(center + QPointF(_scene->width(), 0));
    else if (e->key() == Qt::Key_PageUp) {
        QPointF dy = mapToScene(0, height()) - mapToScene(0, 0);
        centerOn(center + QPointF(-dy.x()/2, -dy.y()/2));
    } else if (e->key() == Qt::Key_PageDown) {
        QPointF dy = mapToScene(0, height()) - mapToScene(0, 0);
        centerOn(center + QPointF(dy.x()/2, dy.y()/2));
    } else if (e->key() == Qt::Key_Left) {
        QPointF dx = mapToScene(width(), 0) - mapToScene(0, 0);
        centerOn(center + QPointF(-dx.x()/10, -dx.y()/10));
    } else if (e->key() == Qt::Key_Right) {
        QPointF dx = mapToScene(width(), 0) - mapToScene(0, 0);
        centerOn(center + QPointF(dx.x()/10, dx.y()/10));
    } else if (e->key() == Qt::Key_Down) {
        QPointF dy = mapToScene(0, height()) - mapToScene(0, 0);
        centerOn(center + QPointF(dy.x()/10, dy.y()/10));
    } else if (e->key() == Qt::Key_Up) {
        QPointF dy = mapToScene(0, height()) - mapToScene(0, 0);
        centerOn(center + QPointF(-dy.x()/10, -dy.y()/10));
    } else
        e->ignore();
}

void CallGraphView::resizeEvent(QResizeEvent* e)
{
    QGraphicsView::resizeEvent(e);
    if (_scene)
        updateSizes(e->size());
}

CostItem* CallGraphView::canShow(CostItem* i)
{
    if (i) {
        switch (i->type()) {
        case ProfileContext::Function:
        case ProfileContext::FunctionCycle:
        case ProfileContext::Call:
            return i;
        default:
            break;
        }
    }
    return 0;
}

void CallGraphView::doUpdate(int changeType, bool)
{
    // Special case ?
    if (changeType == eventType2Changed)
        return;

    if (changeType == selectedItemChanged) {
        if (!_scene)
            return;

        if (!_selectedItem)
            return;

        GraphNode* n = 0;
        GraphEdge* e = 0;
        if ((_selectedItem->type() == ProfileContext::Function)
            ||(_selectedItem->type() == ProfileContext::FunctionCycle)) {
            n = _exporter.node((TraceFunction*)_selectedItem);
            if (n == _selectedNode)
                return;
        } else if (_selectedItem->type() == ProfileContext::Call) {
            TraceCall* c = (TraceCall*)_selectedItem;
            e = _exporter.edge(c->caller(false), c->called(false));
            if (e == _selectedEdge)
                return;
        }

        // unselect any selected item
        if (_selectedNode && _selectedNode->canvasNode()) {
            _selectedNode->canvasNode()->setSelected(false);
        }
        _selectedNode = 0;
        if (_selectedEdge && _selectedEdge->canvasEdge()) {
            _selectedEdge->canvasEdge()->setSelected(false);
        }
        _selectedEdge = 0;

        // select
        CanvasNode* sNode = 0;
        if (n && n->canvasNode()) {
            _selectedNode = n;
            _selectedNode->canvasNode()->setSelected(true);

            if (!_isMoving)
                sNode = _selectedNode->canvasNode();
        }
        if (e && e->canvasEdge()) {
            _selectedEdge = e;
            _selectedEdge->canvasEdge()->setSelected(true);

#if 0 // do not change position when selecting edge
            if (!_isMoving) {
                if (_selectedEdge->fromNode())
                    sNode = _selectedEdge->fromNode()->canvasNode();
                if (!sNode && _selectedEdge->toNode())
                    sNode = _selectedEdge->toNode()->canvasNode();
            }
#endif
        }
        if (sNode)
            ensureVisible(sNode);

        _scene->update();
        return;
    }

    if (changeType == groupTypeChanged) {
        if (!_scene)
            return;

        if (_clusterGroups) {
            refresh();
            return;
        }

        QList<QGraphicsItem *> l = _scene->items();
        for (int i = 0; i < l.size(); ++i)
            if (l[i]->type() == CANVAS_NODE)
                ((CanvasNode*)l[i])->updateGroup();

        _scene->update();
        return;
    }

    if (changeType & dataChanged) {
        // invalidate old selection and graph part
        _exporter.reset(_data, _activeItem, _eventType, _groupType);
        _selectedNode = 0;
        _selectedEdge = 0;
    }

    refresh();
}

void CallGraphView::clear()
{
    if (!_scene)
        return;

    _panningView->setScene(0);
    setScene(0);
    delete _scene;
    _scene = 0;
}

void CallGraphView::showText(QString s)
{
    clear();
    _renderTimer.stop();

    _scene = new QGraphicsScene;

    _scene->addSimpleText(s);
    centerOn(0, 0);
    setScene(_scene);
    _scene->update();
    _panningView->hide();
}

void CallGraphView::showRenderWarning()
{
    QString s;

    if (_renderProcess)
        s = tr("Warning: a long lasting graph layouting is in progress.\n"
               "Reduce node/edge limits for speedup.\n");
    else
        s = tr("Layouting stopped.\n");

    s.append(tr("The call graph has %1 nodes and %2 edges.\n")
             .arg(_exporter.nodeCount()).arg(_exporter.edgeCount()));

    showText(s);
}

void CallGraphView::showRenderError(QString s)
{
    QString err;
    err = tr("No graph available because the layouting process failed.\n");
    if (_renderProcess)
        err += tr("Trying to run the following command did not work:\n"
                  "'%1'\n").arg(_renderProcessCmdLine);
    err += tr("Please check that 'dot' is installed (package GraphViz).");

    if (!s.isEmpty())
        err += QStringLiteral("\n\n%1").arg(s);

    showText(err);
}

void CallGraphView::stopRendering()
{
    if (!_renderProcess)
        return;

    qDebug("CallGraphView::stopRendering: Killing QProcess %p",
           _renderProcess);

    _renderProcess->kill();

    // forget about this process, not interesting any longer
    _renderProcess->deleteLater();
    _renderProcess = 0;
    _unparsedOutput = QString();

    _renderTimer.setSingleShot(true);
    _renderTimer.start(200);
}

void CallGraphView::refresh()
{
    // trigger start of new layouting via 'dot'
    if (_renderProcess)
        stopRendering();

    // we want to keep a selected node item at the same global position
    _prevSelectedNode = _selectedNode;
    _prevSelectedPos = QPoint(-1, -1);
    if (_selectedNode) {
        QPointF center = _selectedNode->canvasNode()->rect().center();
        _prevSelectedPos = mapFromScene(center);
    }

    if (!_data || !_activeItem) {
        showText(tr("No item activated for which to "
                    "draw the call graph."));
        return;
    }

    ProfileContext::Type t = _activeItem->type();
    switch (t) {
    case ProfileContext::Function:
    case ProfileContext::FunctionCycle:
    case ProfileContext::Call:
        break;
    default:
        showText(tr("No call graph can be drawn for "
                    "the active item."));
        return;
    }

    if (1)
        qDebug() << "CallGraphView::refresh";

    _selectedNode = 0;
    _selectedEdge = 0;

    /*
     * Call 'dot' asynchronoulsy in the background with the aim to
     * - have responsive GUI while layout task runs (potentially long!)
     * - notify user about a long run, using a timer
     * - kill long running 'dot' processes when another layout is
     *   requested, as old data is not needed any more
     *
     * Even after killing a process, the QProcess needs some time
     * to make sure the process is destroyed; also, stdout data
     * still can be delivered after killing. Thus, there can/should be
     * multiple QProcess's at one time.
     * The QProcess we currently wait for data from is <_renderProcess>
     * Signals from other QProcesses are ignored with the exception of
     * the finished() signal, which triggers QProcess destruction.
     */
    QString renderProgram;
    QStringList renderArgs;
    if (_layout == GraphOptions::Circular)
        renderProgram = QStringLiteral("twopi");
    else
        renderProgram = QStringLiteral("dot");
    renderArgs << QStringLiteral("-Tplain");

    _unparsedOutput = QString();

    // display warning if layouting takes > 1s
    _renderTimer.setSingleShot(true);
    _renderTimer.start(1000);

    _renderProcess = new QProcess(this);
    connect(_renderProcess, &QProcess::readyReadStandardOutput,
            this, &CallGraphView::readDotOutput);
    connect(_renderProcess, SIGNAL(error(QProcess::ProcessError)),
            this, SLOT(dotError()));
    connect(_renderProcess, SIGNAL(finished(int,QProcess::ExitStatus)),
            this, SLOT(dotExited()));

    _renderProcessCmdLine =  renderProgram + " " + renderArgs.join(QStringLiteral(" "));
    qDebug("CallGraphView::refresh: Starting process %p, '%s'",
           _renderProcess, qPrintable(_renderProcessCmdLine));

    // _renderProcess can be set to 0 on error after start().
    // thus, we use a local copy afterwards
    QProcess* p = _renderProcess;
    p->start(renderProgram, renderArgs);
    _exporter.reset(_data, _activeItem, _eventType, _groupType);
    _exporter.writeDot(p);
    p->closeWriteChannel();
}

void CallGraphView::readDotOutput()
{
    QProcess* p = qobject_cast<QProcess*>(sender());
    qDebug("CallGraphView::readDotOutput: QProcess %p", p);

    // signal from old/uninteresting process?
    if ((_renderProcess == 0) || (p != _renderProcess)) {
        p->deleteLater();
        return;
    }

    _unparsedOutput.append(QString::fromLocal8Bit(_renderProcess->readAllStandardOutput()));
}

void CallGraphView::dotError()
{
    QProcess* p = qobject_cast<QProcess*>(sender());
    qDebug("CallGraphView::dotError: Got %d from QProcess %p",
           p->error(), p);

    // signal from old/uninteresting process?
    if ((_renderProcess == 0) || (p != _renderProcess)) {
        p->deleteLater();
        return;
    }

    showRenderError(QString::fromLocal8Bit(_renderProcess->readAllStandardError()));

    // not interesting any longer
    _renderProcess->deleteLater();
    _renderProcess = 0;
}


void CallGraphView::dotExited()
{
    QProcess* p = qobject_cast<QProcess*>(sender());
    qDebug("CallGraphView::dotExited: QProcess %p", p);

    // signal from old/uninteresting process?
    if ((_renderProcess == 0) || (p != _renderProcess)) {
        p->deleteLater();
        return;
    }

    _unparsedOutput.append(QString::fromLocal8Bit(_renderProcess->readAllStandardOutput()));
    _renderProcess->deleteLater();
    _renderProcess = 0;

    QString line, cmd;
    CanvasNode *rItem;
    QGraphicsEllipseItem* eItem;
    CanvasEdge* sItem;
    CanvasEdgeLabel* lItem;
    QTextStream* dotStream;
    double scale = 1.0, scaleX = 1.0, scaleY = 1.0;
    double dotWidth = 0, dotHeight = 0;
    GraphNode* activeNode = 0;
    GraphEdge* activeEdge = 0;

    _renderTimer.stop();
    viewport()->setUpdatesEnabled(false);
    clear();
    dotStream = new QTextStream(&_unparsedOutput, QIODevice::ReadOnly);

    // First pass to adjust coordinate scaling by node height given from dot
    // Normal detail level (=1) should be 3 lines using general KDE font
    double nodeHeight = 0.0;
    while(1) {
        line = dotStream->readLine();
        if (line.isNull()) break;
        if (line.isEmpty()) continue;
        QTextStream lineStream(&line, QIODevice::ReadOnly);
        lineStream >> cmd;
        if (cmd != QLatin1String("node")) continue;
        QString s, h;
        lineStream >> s /*name*/ >> s /*x*/ >> s /*y*/ >> s /*width*/ >> h /*height*/;
        nodeHeight = h.toDouble();
        break;
    }
    if (nodeHeight > 0.0) {
        scaleY = (8 + (1 + 2 * _detailLevel) * fontMetrics().height()) / nodeHeight;
        scaleX = 80;
    }
    dotStream->seek(0);
    int lineno = 0;
    while (1) {
        line = dotStream->readLine();
        if (line.isNull())
            break;

        lineno++;
        if (line.isEmpty())
            continue;

        QTextStream lineStream(&line, QIODevice::ReadOnly);
        lineStream >> cmd;

        if (0)
            qDebug("%s:%d - line '%s', cmd '%s'",
                   qPrintable(_exporter.filename()),
                   lineno, qPrintable(line), qPrintable(cmd));

        if (cmd == QLatin1String("stop"))
            break;

        if (cmd == QLatin1String("graph")) {
            QString dotWidthString, dotHeightString;
            // scale will not be used
            lineStream >> scale >> dotWidthString >> dotHeightString;
            dotWidth = dotWidthString.toDouble();
            dotHeight = dotHeightString.toDouble();

            if (!_scene) {
                int w = (int)(scaleX * dotWidth);
                int h = (int)(scaleY * dotHeight);

                // We use as minimum canvas size the desktop size.
                // Otherwise, the canvas would have to be resized on widget resize.
                _xMargin = 50;
                if (w < QApplication::desktop()->width())
                    _xMargin += (QApplication::desktop()->width()-w)/2;

                _yMargin = 50;
                if (h < QApplication::desktop()->height())
                    _yMargin += (QApplication::desktop()->height()-h)/2;

                _scene = new QGraphicsScene( 0.0, 0.0,
                                             qreal(w+2*_xMargin), qreal(h+2*_yMargin));
                // Change background color for call graph from default system color to
                // white. It has to blend into the gradient for the selected function.
                _scene->setBackgroundBrush(Qt::white);

#if DEBUG_GRAPH
                qDebug() << qPrintable(_exporter.filename()) << ":" << lineno
                         << " - graph (" << dotWidth << " x " << dotHeight
                         << ") => (" << w << " x " << h << ")";
#endif
            } else
                qDebug() << "Ignoring 2nd 'graph' from dot ("
                         << _exporter.filename() << ":"<< lineno << ")";
            continue;
        }

        if ((cmd != QLatin1String("node")) && (cmd != QLatin1String("edge"))) {
            qDebug() << "Ignoring unknown command '"<< cmd
                     << "' from dot ("<< _exporter.filename() << ":"<< lineno
                     << ")";
            continue;
        }

        if (_scene == 0) {
            qDebug() << "Ignoring '"<< cmd
                     << "' without 'graph' from dot ("<< _exporter.filename()
                     << ":"<< lineno << ")";
            continue;
        }

        if (cmd == QLatin1String("node")) {
            // x, y are centered in node
            QString nodeName, nodeX, nodeY, nodeWidth, nodeHeight;
            double x, y, width, height;
            lineStream >> nodeName >> nodeX >> nodeY >> nodeWidth
                    >> nodeHeight;
            x = nodeX.toDouble();
            y = nodeY.toDouble();
            width = nodeWidth.toDouble();
            height = nodeHeight.toDouble();

            GraphNode* n = _exporter.node(_exporter.toFunc(nodeName));

            int xx = (int)(scaleX * x + _xMargin);
            int yy = (int)(scaleY * (dotHeight - y)+ _yMargin);
            int w = (int)(scaleX * width);
            int h = (int)(scaleY * height);

#if DEBUG_GRAPH
            qDebug() << _exporter.filename() << ":" << lineno
                     << " - node '" << nodeName << "' ( "
                     << x << "/" << y << " - "
                     << width << "x" << height << " ) => ("
                     << xx-w/2 << "/" << yy-h/2 << " - "
                     << w << "x" << h << ")" << endl;
#endif

            // Unnamed nodes with collapsed edges (with 'R' and 'S')
            if (nodeName[0] == 'R'|| nodeName[0] == 'S') {
                w = 10, h = 10;
                eItem = new QGraphicsEllipseItem( QRectF(xx-w/2, yy-h/2, w, h) );
                _scene->addItem(eItem);
                eItem->setBrush(Qt::gray);
                eItem->setZValue(1.0);
                eItem->show();
                continue;
            }

            if (!n) {
                qDebug("Warning: Unknown function '%s' ?!",
                       qPrintable(nodeName));
                continue;
            }
            n->setVisible(true);

            rItem = new CanvasNode(this, n, xx-w/2, yy-h/2, w, h);
            // limit symbol space to a maximal number of lines depending on detail level
            if (_detailLevel>0) rItem->setMaxLines(0, 2*_detailLevel);
            _scene->addItem(rItem);
            n->setCanvasNode(rItem);

            if (n) {
                if (n->function() == activeItem())
                    activeNode = n;
                if (n->function() == selectedItem())
                    _selectedNode = n;
                rItem->setSelected(n == _selectedNode);
            }

            rItem->setZValue(1.0);
            rItem->show();

            continue;
        }

        // edge

        QString node1Name, node2Name, label, edgeX, edgeY;
        double x, y;
        QPolygon poly;
        int points, i;
        lineStream >> node1Name >> node2Name >> points;

        GraphEdge* e = _exporter.edge(_exporter.toFunc(node1Name),
                                      _exporter.toFunc(node2Name));
        if (!e) {
            qDebug() << "Unknown edge '"<< node1Name << "'-'"<< node2Name
                     << "' from dot ("<< _exporter.filename() << ":"<< lineno
                     << ")";
            continue;
        }
        e->setVisible(true);
        if (e->fromNode())
            e->fromNode()->addCallee(e);
        if (e->toNode())
            e->toNode()->addCaller(e);

        if (0)
            qDebug("  Edge with %d points:", points);

        poly.resize(points);
        for (i=0; i<points; ++i) {
            if (lineStream.atEnd())
                break;
            lineStream >> edgeX >> edgeY;
            x = edgeX.toDouble();
            y = edgeY.toDouble();

            int xx = (int)(scaleX * x + _xMargin);
            int yy = (int)(scaleY * (dotHeight - y)+ _yMargin);

            if (0)
                qDebug("   P %d: ( %f / %f ) => ( %d / %d)", i, x, y, xx, yy);

            poly.setPoint(i, xx, yy);
        }
        if (i < points) {
            qDebug("CallGraphView: Can not read %d spline points (%s:%d)",
                   points, qPrintable(_exporter.filename()), lineno);
            continue;
        }

        // calls into/out of cycles are special: make them blue
        QColor arrowColor = Qt::black;
        TraceFunction* caller = e->fromNode() ? e->fromNode()->function() : 0;
        TraceFunction* called = e->toNode() ? e->toNode()->function() : 0;
        if ( (caller && (caller->cycle() == caller)) ||
             (called && (called->cycle() == called)) ) arrowColor = Qt::blue;

        sItem = new CanvasEdge(e);
        _scene->addItem(sItem);
        e->setCanvasEdge(sItem);
        sItem->setControlPoints(poly);
        // width of pen will be adjusted in CanvasEdge::paint()
        sItem->setPen(QPen(arrowColor));
        sItem->setZValue(0.5);
        sItem->show();

        if (e->call() == selectedItem())
            _selectedEdge = e;
        if (e->call() == activeItem())
            activeEdge = e;
        sItem->setSelected(e == _selectedEdge);

        // Arrow head
        QPoint arrowDir;
        int indexHead = -1;

        // check if head is at start of spline...
        // this is needed because dot always gives points from top to bottom
        CanvasNode* fromNode = e->fromNode() ? e->fromNode()->canvasNode() : 0;
        if (fromNode) {
            QPointF toCenter = fromNode->rect().center();
            qreal dx0 = poly.point(0).x() - toCenter.x();
            qreal dy0 = poly.point(0).y() - toCenter.y();
            qreal dx1 = poly.point(points-1).x() - toCenter.x();
            qreal dy1 = poly.point(points-1).y() - toCenter.y();
            if (dx0*dx0+dy0*dy0 > dx1*dx1+dy1*dy1) {
                // start of spline is nearer to call target node
                indexHead=-1;
                while (arrowDir.isNull() && (indexHead<points-2)) {
                    indexHead++;
                    arrowDir = poly.point(indexHead) - poly.point(indexHead+1);
                }
            }
        }

        if (arrowDir.isNull()) {
            indexHead = points;
            // sometimes the last spline points from dot are the same...
            while (arrowDir.isNull() && (indexHead>1)) {
                indexHead--;
                arrowDir = poly.point(indexHead) - poly.point(indexHead-1);
            }
        }

        if (!arrowDir.isNull()) {
            // arrow around pa.point(indexHead) with direction arrowDir
            arrowDir *= 10.0/sqrt(double(arrowDir.x()*arrowDir.x() +
                                         arrowDir.y()*arrowDir.y()));

            QPolygonF a;
            a << QPointF(poly.point(indexHead) + arrowDir);
            a << QPointF(poly.point(indexHead) + QPoint(arrowDir.y()/2,
                                                        -arrowDir.x()/2));
            a << QPointF(poly.point(indexHead) + QPoint(-arrowDir.y()/2,
                                                        arrowDir.x()/2));

            if (0)
                qDebug("  Arrow: ( %f/%f, %f/%f, %f/%f)", a[0].x(), a[0].y(),
                        a[1].x(), a[1].y(), a[2].x(), a[1].y());

            CanvasEdgeArrow* aItem = new CanvasEdgeArrow(sItem);
            _scene->addItem(aItem);
            aItem->setPolygon(a);
            aItem->setBrush(arrowColor);
            aItem->setZValue(1.5);
            aItem->show();

            sItem->setArrow(aItem);
        }

        if (lineStream.atEnd())
            continue;

        // parse quoted label
        QChar c;
        lineStream >> c;
        while (c.isSpace())
            lineStream >> c;
        if (c != '\"') {
            lineStream >> label;
            label = c + label;
        } else {
            lineStream >> c;
            while (!c.isNull() && (c != '\"')) {
                //if (c == '\\') lineStream >> c;

                label += c;
                lineStream >> c;
            }
        }
        lineStream >> edgeX >> edgeY;
        x = edgeX.toDouble();
        y = edgeY.toDouble();

        int xx = (int)(scaleX * x + _xMargin);
        int yy = (int)(scaleY * (dotHeight - y)+ _yMargin);

        if (0)
            qDebug("   Label '%s': ( %f / %f ) => ( %d / %d)",
                   qPrintable(label), x, y, xx, yy);

        // Fixed Dimensions for Label: 100 x 40
        int w = 100;
        int h = _detailLevel * 20;
        lItem = new CanvasEdgeLabel(this, sItem, xx-w/2, yy-h/2, w, h);
        _scene->addItem(lItem);
        // edge labels above nodes
        lItem->setZValue(1.5);
        sItem->setLabel(lItem);
        if (h>0)
            lItem->show();

    }
    delete dotStream;

    // for keyboard navigation
    _exporter.sortEdges();

    if (!_scene) {
        _scene = new QGraphicsScene;

        QString s = tr("Error running the graph layouting tool.\n");
        s += tr("Please check that 'dot' is installed (package GraphViz).");
        _scene->addSimpleText(s);
        centerOn(0, 0);
    } else if (!activeNode && !activeEdge) {
        QString s = tr("There is no call graph available for function\n"
                       "\t'%1'\n"
                       "because it has no cost of the selected event type.")
                    .arg(_activeItem->name());
        _scene->addSimpleText(s);
        centerOn(0, 0);
    }

    _panningView->setScene(_scene);
    setScene(_scene);

    // if we do not have a selection, or the old selection is not
    // in visible graph, make active function selected for this view
    if ((!_selectedNode || !_selectedNode->canvasNode()) &&
        (!_selectedEdge || !_selectedEdge->canvasEdge())) {
        if (activeNode) {
            _selectedNode = activeNode;
            _selectedNode->canvasNode()->setSelected(true);
        } else if (activeEdge) {
            _selectedEdge = activeEdge;
            _selectedEdge->canvasEdge()->setSelected(true);
        }
    }

    CanvasNode* sNode = 0;
    if (_selectedNode)
        sNode = _selectedNode->canvasNode();
    else if (_selectedEdge) {
        if (_selectedEdge->fromNode())
            sNode = _selectedEdge->fromNode()->canvasNode();
        if (!sNode && _selectedEdge->toNode())
            sNode = _selectedEdge->toNode()->canvasNode();
    }

    if (sNode) {
        if (_prevSelectedNode) {
            QPointF prevPos = mapToScene(_prevSelectedPos);
            if (rect().contains(_prevSelectedPos)) {
                QPointF wCenter = mapToScene(viewport()->rect().center());
                centerOn(sNode->rect().center() +
                         wCenter - prevPos);
            }
            else
                ensureVisible(sNode);
        } else
            centerOn(sNode);
    }

    if (activeNode) {
        CanvasNode* cn = activeNode->canvasNode();
        CanvasFrame* f = new CanvasFrame(cn);
        _scene->addItem(f);
        f->setPos(cn->pos());
        f->setZValue(-1);
    }

    _panningZoom = 0;
    updateSizes();

    _scene->update();
    viewport()->setUpdatesEnabled(true);

    delete _renderProcess;
    _renderProcess = 0;
}


// Called by QAbstractScrollArea to notify about scrollbar changes
void CallGraphView::scrollContentsBy(int dx, int dy)
{
    // call QGraphicsView implementation
    QGraphicsView::scrollContentsBy(dx, dy);

    QPointF topLeft = mapToScene(QPoint(0, 0));
    QPointF bottomRight = mapToScene(QPoint(width(), height()));

    QRectF z(topLeft, bottomRight);
    if (0)
        qDebug("CallGraphView::scrollContentsBy(dx %d, dy %d) - to (%f,%f - %f,%f)",
               dx, dy, topLeft.x(), topLeft.y(),
               bottomRight.x(), bottomRight.y());
    _panningView->setZoomRect(z);
}

void CallGraphView::zoomRectMoved(qreal dx, qreal dy)
{
    //FIXME if (leftMargin()>0) dx = 0;
    //FIXME if (topMargin()>0) dy = 0;

    QScrollBar *hBar = horizontalScrollBar();
    QScrollBar *vBar = verticalScrollBar();
    hBar->setValue(hBar->value() + int(dx));
    vBar->setValue(vBar->value() + int(dy));
}

void CallGraphView::zoomRectMoveFinished()
{
    if (_zoomPosition == Auto)
        updateSizes();
}

void CallGraphView::mousePressEvent(QMouseEvent* e)
{
    // clicking on the viewport sets focus
    setFocus();

    // activate scroll mode on left click
    if (e->button() == Qt::LeftButton)	_isMoving = true;

    QGraphicsItem* i = itemAt(e->pos());
    if (i) {

        if (i->type() == CANVAS_NODE) {
            GraphNode* n = ((CanvasNode*)i)->node();
            if (0)
                qDebug("CallGraphView: Got Node '%s'",
                       qPrintable(n->function()->prettyName()));

            selected(n->function());
        }

        // redirect from label / arrow to edge
        if (i->type() == CANVAS_EDGELABEL)
            i = ((CanvasEdgeLabel*)i)->canvasEdge();
        if (i->type() == CANVAS_EDGEARROW)
            i = ((CanvasEdgeArrow*)i)->canvasEdge();

        if (i->type() == CANVAS_EDGE) {
            GraphEdge* e = ((CanvasEdge*)i)->edge();
            if (0)
                qDebug("CallGraphView: Got Edge '%s'",
                       qPrintable(e->prettyName()));

            if (e->call())
                selected(e->call());
        }
    }
    _lastPos = e->pos();
}

void CallGraphView::mouseMoveEvent(QMouseEvent* e)
{
    if (_isMoving) {
        QPoint delta = e->pos() - _lastPos;

        QScrollBar *hBar = horizontalScrollBar();
        QScrollBar *vBar = verticalScrollBar();
        hBar->setValue(hBar->value() - delta.x());
        vBar->setValue(vBar->value() - delta.y());

        _lastPos = e->pos();
    }
}

void CallGraphView::mouseReleaseEvent(QMouseEvent*)
{
    _isMoving = false;
    if (_zoomPosition == Auto)
        updateSizes();
}

void CallGraphView::mouseDoubleClickEvent(QMouseEvent* e)
{
    QGraphicsItem* i = itemAt(e->pos());
    if (i == 0)
        return;

    if (i->type() == CANVAS_NODE) {
        GraphNode* n = ((CanvasNode*)i)->node();
        if (0)
            qDebug("CallGraphView: Double Clicked on Node '%s'",
                   qPrintable(n->function()->prettyName()));

        activated(n->function());
    }

    // redirect from label / arrow to edge
    if (i->type() == CANVAS_EDGELABEL)
        i = ((CanvasEdgeLabel*)i)->canvasEdge();
    if (i->type() == CANVAS_EDGEARROW)
        i = ((CanvasEdgeArrow*)i)->canvasEdge();

    if (i->type() == CANVAS_EDGE) {
        GraphEdge* e = ((CanvasEdge*)i)->edge();
        if (e->call()) {
            if (0)
                qDebug("CallGraphView: Double Clicked On Edge '%s'",
                       qPrintable(e->call()->prettyName()));

            activated(e->call());
        }
    }
}

// helper functions for context menu:
// submenu builders and trigger handlers

QAction* CallGraphView::addCallerDepthAction(QMenu* m, QString s, int d)
{
    QAction* a;

    a = m->addAction(s);
    a->setData(d);
    a->setCheckable(true);
    a->setChecked(_maxCallerDepth == d);

    return a;
}

QMenu* CallGraphView::addCallerDepthMenu(QMenu* menu)
{
    QAction* a;
    QMenu* m;

    m = menu->addMenu(tr("Caller Depth"));
    a = addCallerDepthAction(m, tr("Unlimited"), -1);
    a->setEnabled(_funcLimit>0.005);
    m->addSeparator();
    addCallerDepthAction(m, tr("Depth 0", "None"), 0);
    addCallerDepthAction(m, tr("max. 1"), 1);
    addCallerDepthAction(m, tr("max. 2"), 2);
    addCallerDepthAction(m, tr("max. 5"), 5);
    addCallerDepthAction(m, tr("max. 10"), 10);
    addCallerDepthAction(m, tr("max. 15"), 15);

    connect(m, &QMenu::triggered,
            this, &CallGraphView::callerDepthTriggered );

    return m;
}

void CallGraphView::callerDepthTriggered(QAction* a)
{
    _maxCallerDepth = a->data().toInt(0);
    refresh();
}

QAction* CallGraphView::addCalleeDepthAction(QMenu* m, QString s, int d)
{
    QAction* a;

    a = m->addAction(s);
    a->setData(d);
    a->setCheckable(true);
    a->setChecked(_maxCalleeDepth == d);

    return a;
}

QMenu* CallGraphView::addCalleeDepthMenu(QMenu* menu)
{
    QAction* a;
    QMenu* m;

    m = menu->addMenu(tr("Callee Depth"));
    a = addCalleeDepthAction(m, tr("Unlimited"), -1);
    a->setEnabled(_funcLimit>0.005);
    m->addSeparator();
    addCalleeDepthAction(m, tr("Depth 0", "None"), 0);
    addCalleeDepthAction(m, tr("max. 1"), 1);
    addCalleeDepthAction(m, tr("max. 2"), 2);
    addCalleeDepthAction(m, tr("max. 5"), 5);
    addCalleeDepthAction(m, tr("max. 10"), 10);
    addCalleeDepthAction(m, tr("max. 15"), 15);

    connect(m, &QMenu::triggered,
            this, &CallGraphView::calleeDepthTriggered );

    return m;
}

void CallGraphView::calleeDepthTriggered(QAction* a)
{
    _maxCalleeDepth = a->data().toInt(0);
    refresh();
}

QAction* CallGraphView::addNodeLimitAction(QMenu* m, QString s, double l)
{
    QAction* a;

    a = m->addAction(s);
    a->setData(l);
    a->setCheckable(true);
    a->setChecked(_funcLimit == l);

    return a;
}

QMenu* CallGraphView::addNodeLimitMenu(QMenu* menu)
{
    QAction* a;
    QMenu* m;

    m = menu->addMenu(tr("Min. Node Cost"));
    a = addNodeLimitAction(m, tr("No Minimum"), 0.0);
    // Unlimited node cost easily produces huge graphs such that 'dot'
    // would need a long time to layout. For responsiveness, we only allow
    // for unlimited node cost if a caller and callee depth limit is set.
    a->setEnabled((_maxCallerDepth>=0) && (_maxCalleeDepth>=0));
    m->addSeparator();
    addNodeLimitAction(m, tr("50 %"), .5);
    addNodeLimitAction(m, tr("20 %"), .2);
    addNodeLimitAction(m, tr("10 %"), .1);
    addNodeLimitAction(m, tr("5 %"), .05);
    addNodeLimitAction(m, tr("2 %"), .02);
    addNodeLimitAction(m, tr("1 %"), .01);

    connect(m, &QMenu::triggered,
            this, &CallGraphView::nodeLimitTriggered );

    return m;
}

void CallGraphView::nodeLimitTriggered(QAction* a)
{
    _funcLimit = a->data().toDouble(0);
    refresh();
}

QAction* CallGraphView::addCallLimitAction(QMenu* m, QString s, double l)
{
    QAction* a;

    a = m->addAction(s);
    a->setData(l);
    a->setCheckable(true);
    a->setChecked(_callLimit == l);

    return a;
}

QMenu* CallGraphView::addCallLimitMenu(QMenu* menu)
{
    QMenu* m;

    m = menu->addMenu(tr("Min. Call Cost"));
    addCallLimitAction(m, tr("Same as Node"), 1.0);
    // xgettext: no-c-format
    addCallLimitAction(m, tr("50 % of Node"), .5);
    // xgettext: no-c-format
    addCallLimitAction(m, tr("20 % of Node"), .2);
    // xgettext: no-c-format
    addCallLimitAction(m, tr("10 % of Node"), .1);

    connect(m, &QMenu::triggered,
            this, &CallGraphView::callLimitTriggered );

    return m;
}

void CallGraphView::callLimitTriggered(QAction* a)
{
    _callLimit = a->data().toDouble(0);
    refresh();
}

QAction* CallGraphView::addZoomPosAction(QMenu* m, QString s,
                                         CallGraphView::ZoomPosition p)
{
    QAction* a;

    a = m->addAction(s);
    a->setData((int)p);
    a->setCheckable(true);
    a->setChecked(_zoomPosition == p);

    return a;
}

QMenu* CallGraphView::addZoomPosMenu(QMenu* menu)
{
    QMenu* m = menu->addMenu(tr("Birds-eye View"));
    addZoomPosAction(m, tr("Top Left"), TopLeft);
    addZoomPosAction(m, tr("Top Right"), TopRight);
    addZoomPosAction(m, tr("Bottom Left"), BottomLeft);
    addZoomPosAction(m, tr("Bottom Right"), BottomRight);
    addZoomPosAction(m, tr("Automatic"), Auto);
    addZoomPosAction(m, tr("Hide"), Hide);

    connect(m, &QMenu::triggered,
            this, &CallGraphView::zoomPosTriggered );

    return m;
}


void CallGraphView::zoomPosTriggered(QAction* a)
{
    _zoomPosition = (ZoomPosition) a->data().toInt(0);
    updateSizes();
}

QAction* CallGraphView::addLayoutAction(QMenu* m, QString s,
                                        GraphOptions::Layout l)
{
    QAction* a;

    a = m->addAction(s);
    a->setData((int)l);
    a->setCheckable(true);
    a->setChecked(_layout == l);

    return a;
}

QMenu* CallGraphView::addLayoutMenu(QMenu* menu)
{
    QMenu* m = menu->addMenu(tr("Layout"));
    addLayoutAction(m, tr("Top to Down"), TopDown);
    addLayoutAction(m, tr("Left to Right"), LeftRight);
    addLayoutAction(m, tr("Circular"), Circular);

    connect(m, &QMenu::triggered,
            this, &CallGraphView::layoutTriggered );

    return m;
}


void CallGraphView::layoutTriggered(QAction* a)
{
    _layout = (Layout) a->data().toInt(0);
    refresh();
}


void CallGraphView::contextMenuEvent(QContextMenuEvent* e)
{
    _isMoving = false;

    QGraphicsItem* i = itemAt(e->pos());

    QMenu popup;
    TraceFunction *f = 0, *cycle = 0;
    TraceCall* c = 0;

    QAction* activateFunction = 0;
    QAction* activateCycle = 0;
    QAction* activateCall = 0;
    if (i) {
        if (i->type() == CANVAS_NODE) {
            GraphNode* n = ((CanvasNode*)i)->node();
            if (0)
                qDebug("CallGraphView: Menu on Node '%s'",
                       qPrintable(n->function()->prettyName()));

            f = n->function();
            cycle = f->cycle();

            QString name = f->prettyName();
            QString menuStr = tr("Go to '%1'")
                              .arg(GlobalConfig::shortenSymbol(name));
            activateFunction = popup.addAction(menuStr);
            if (cycle && (cycle != f)) {
                name = GlobalConfig::shortenSymbol(cycle->prettyName());
                activateCycle = popup.addAction(tr("Go to '%1'").arg(name));
            }
            popup.addSeparator();
        }

        // redirect from label / arrow to edge
        if (i->type() == CANVAS_EDGELABEL)
            i = ((CanvasEdgeLabel*)i)->canvasEdge();
        if (i->type() == CANVAS_EDGEARROW)
            i = ((CanvasEdgeArrow*)i)->canvasEdge();

        if (i->type() == CANVAS_EDGE) {
            GraphEdge* e = ((CanvasEdge*)i)->edge();
            if (0)
                qDebug("CallGraphView: Menu on Edge '%s'",
                       qPrintable(e->prettyName()));

            c = e->call();
            if (c) {
                QString name = c->prettyName();
                QString menuStr = tr("Go to '%1'")
                                  .arg(GlobalConfig::shortenSymbol(name));
                activateCall = popup.addAction(menuStr);

                popup.addSeparator();
            }
        }
    }

    QAction* stopLayout = 0;
    if (_renderProcess) {
        stopLayout = popup.addAction(tr("Stop Layouting"));
        popup.addSeparator();
    }

    addGoMenu(&popup);
    popup.addSeparator();

    QMenu* epopup = popup.addMenu(tr("Export Graph"));
    QAction* exportAsDot = epopup->addAction(tr("As DOT file..."));
    QAction* exportAsImage = epopup->addAction(tr("As Image..."));
    popup.addSeparator();

    QMenu* gpopup = popup.addMenu(tr("Graph"));
    addCallerDepthMenu(gpopup);
    addCalleeDepthMenu(gpopup);
    addNodeLimitMenu(gpopup);
    addCallLimitMenu(gpopup);
    gpopup->addSeparator();

    QAction* toggleSkipped;
    toggleSkipped = gpopup->addAction(tr("Arrows for Skipped Calls"));
    toggleSkipped->setCheckable(true);
    toggleSkipped->setChecked(_showSkipped);

    QAction* toggleExpand;
    toggleExpand = gpopup->addAction(tr("Inner-cycle Calls"));
    toggleExpand->setCheckable(true);
    toggleExpand->setChecked(_expandCycles);

    QAction* toggleCluster;
    toggleCluster = gpopup->addAction(tr("Cluster Groups"));
    toggleCluster->setCheckable(true);
    toggleCluster->setChecked(_clusterGroups);

    QMenu* vpopup = popup.addMenu(tr("Visualization"));
    QAction* layoutCompact = vpopup->addAction(tr("Compact"));
    layoutCompact->setCheckable(true);
    layoutCompact->setChecked(_detailLevel == 0);
    QAction* layoutNormal = vpopup->addAction(tr("Normal"));
    layoutNormal->setCheckable(true);
    layoutNormal->setChecked(_detailLevel == 1);
    QAction* layoutTall = vpopup->addAction(tr("Tall"));
    layoutTall->setCheckable(true);
    layoutTall->setChecked(_detailLevel == 2);

    addLayoutMenu(&popup);
    addZoomPosMenu(&popup);

    QAction* a = popup.exec(e->globalPos());

    if (a == activateFunction)
        activated(f);
    else if (a == activateCycle)
        activated(cycle);
    else if (a == activateCall)
        activated(c);

    else if (a == stopLayout)
        stopRendering();

    else if (a == exportAsDot) {
        TraceFunction* f = activeFunction();
        if (!f) return;

        QString n;
        n = QFileDialog::getSaveFileName(this,
                                         tr("Export Graph As DOT file"),
                                         QString(), tr("Graphviz (*.dot)"));

        if (!n.isEmpty()) {
            GraphExporter ge(TraceItemView::data(), f, eventType(),
                             groupType(), n);
            ge.setGraphOptions(this);
            ge.writeDot();
        }
    }
    else if (a == exportAsImage) {
        // write current content of canvas as image to file
        if (!_scene) return;

        QString n;
        n = QFileDialog::getSaveFileName(this,
                                         tr("Export Graph As Image"),
                                         QString(),
                                         tr("Images (*.png *.jpg)"));

        if (!n.isEmpty()) {
            QRect r = _scene->sceneRect().toRect();
            QPixmap pix(r.width(), r.height());
            QPainter p(&pix);
            _scene->render( &p );
            pix.save(n);
        }
    }

    else if (a == toggleSkipped) {
        _showSkipped = !_showSkipped;
        refresh();
    }
    else if (a == toggleExpand) {
        _expandCycles = !_expandCycles;
        refresh();
    }
    else if (a == toggleCluster) {
        _clusterGroups = !_clusterGroups;
        refresh();
    }

    else if (a == layoutCompact) {
        _detailLevel = 0;
        refresh();
    }
    else if (a == layoutNormal) {
        _detailLevel = 1;
        refresh();
    }
    else if (a == layoutTall) {
        _detailLevel = 2;
        refresh();
    }
}


CallGraphView::ZoomPosition CallGraphView::zoomPos(QString s)
{
    if (s == QStringLiteral("TopLeft"))
        return TopLeft;
    if (s == QStringLiteral("TopRight"))
        return TopRight;
    if (s == QStringLiteral("BottomLeft"))
        return BottomLeft;
    if (s == QStringLiteral("BottomRight"))
        return BottomRight;
    if (s == QStringLiteral("Automatic"))
        return Auto;
    if (s == QStringLiteral("Hide"))
        return Hide;

    return DEFAULT_ZOOMPOS;
}

QString CallGraphView::zoomPosString(ZoomPosition p)
{
    if (p == TopLeft)
        return QStringLiteral("TopLeft");
    if (p == TopRight)
        return QStringLiteral("TopRight");
    if (p == BottomLeft)
        return QStringLiteral("BottomLeft");
    if (p == BottomRight)
        return QStringLiteral("BottomRight");
    if (p == Auto)
        return QStringLiteral("Automatic");
    if (p == Hide)
        return QStringLiteral("Hide");

    return QString();
}

void CallGraphView::restoreOptions(const QString& prefix, const QString& postfix)
{
    ConfigGroup* g = ConfigStorage::group(prefix, postfix);

    _maxCallerDepth = g->value(QStringLiteral("MaxCaller"), DEFAULT_MAXCALLER).toInt();
    _maxCalleeDepth = g->value(QStringLiteral("MaxCallee"), DEFAULT_MAXCALLEE).toInt();
    _funcLimit = g->value(QStringLiteral("FuncLimit"), DEFAULT_FUNCLIMIT).toDouble();
    _callLimit = g->value(QStringLiteral("CallLimit"), DEFAULT_CALLLIMIT).toDouble();
    _showSkipped = g->value(QStringLiteral("ShowSkipped"), DEFAULT_SHOWSKIPPED).toBool();
    _expandCycles = g->value(QStringLiteral("ExpandCycles"), DEFAULT_EXPANDCYCLES).toBool();
    _clusterGroups = g->value(QStringLiteral("ClusterGroups"), DEFAULT_CLUSTERGROUPS).toBool();
    _detailLevel = g->value(QStringLiteral("DetailLevel"), DEFAULT_DETAILLEVEL).toInt();
    _layout = GraphOptions::layout(g->value(QStringLiteral("Layout"),
                                            layoutString(DEFAULT_LAYOUT)).toString());
    _zoomPosition = zoomPos(g->value(QStringLiteral("ZoomPosition"),
                                     zoomPosString(DEFAULT_ZOOMPOS)).toString());

    delete g;
}

void CallGraphView::saveOptions(const QString& prefix, const QString& postfix)
{
    ConfigGroup* g = ConfigStorage::group(prefix + postfix);

    g->setValue(QStringLiteral("MaxCaller"), _maxCallerDepth, DEFAULT_MAXCALLER);
    g->setValue(QStringLiteral("MaxCallee"), _maxCalleeDepth, DEFAULT_MAXCALLEE);
    g->setValue(QStringLiteral("FuncLimit"), _funcLimit, DEFAULT_FUNCLIMIT);
    g->setValue(QStringLiteral("CallLimit"), _callLimit, DEFAULT_CALLLIMIT);
    g->setValue(QStringLiteral("ShowSkipped"), _showSkipped, DEFAULT_SHOWSKIPPED);
    g->setValue(QStringLiteral("ExpandCycles"), _expandCycles, DEFAULT_EXPANDCYCLES);
    g->setValue(QStringLiteral("ClusterGroups"), _clusterGroups, DEFAULT_CLUSTERGROUPS);
    g->setValue(QStringLiteral("DetailLevel"), _detailLevel, DEFAULT_DETAILLEVEL);
    g->setValue(QStringLiteral("Layout"), layoutString(_layout), layoutString(DEFAULT_LAYOUT));
    g->setValue(QStringLiteral("ZoomPosition"), zoomPosString(_zoomPosition),
                zoomPosString(DEFAULT_ZOOMPOS));

    delete g;
}


