unsigned int
NBNodeCont::removeUnwishedNodes(NBDistrictCont& dc, NBEdgeCont& ec,
                                NBJoinedEdgesMap& je, NBTrafficLightLogicCont& tlc,
                                bool removeGeometryNodes) {
    unsigned int no = 0;
    std::vector<NBNode*> toRemove;
    for (NodeCont::iterator i = myNodes.begin(); i != myNodes.end(); i++) {
        NBNode* current = (*i).second;
        bool remove = false;
        std::vector<std::pair<NBEdge*, NBEdge*> > toJoin;
        // check for completely empty nodes
        if (current->getOutgoingEdges().size() == 0 && current->getIncomingEdges().size() == 0) {
            // remove if empty
            remove = true;
        }
        // check for nodes which are only geometry nodes
        if (removeGeometryNodes) {
            if ((current->getOutgoingEdges().size() == 1 && current->getIncomingEdges().size() == 1)
                    ||
                    (current->getOutgoingEdges().size() == 2 && current->getIncomingEdges().size() == 2)) {
                // ok, one in, one out or two in, two out
                //  -> ask the node whether to join
                remove = current->checkIsRemovable();
                if (remove) {
                    toJoin = current->getEdgesToJoin();
                }
            }
        }
        // remove the node and join the geometries when wished
        if (!remove) {
            continue;
        }
        for (std::vector<std::pair<NBEdge*, NBEdge*> >::iterator j = toJoin.begin(); j != toJoin.end(); j++) {
            NBEdge* begin = (*j).first;
            NBEdge* continuation = (*j).second;
            begin->append(continuation);
            continuation->getToNode()->replaceIncoming(continuation, begin, 0);
            tlc.replaceRemoved(continuation, -1, begin, -1);
            je.appended(begin->getID(), continuation->getID());
            ec.erase(dc, continuation);
        }
        toRemove.push_back(current);
        no++;
    }
    // erase all
    for (std::vector<NBNode*>::iterator j = toRemove.begin(); j != toRemove.end(); ++j) {
        erase(*j);
    }
    return no;
}
void
NBNodeCont::joinNodeClusters(NodeClusters clusters,
                             NBDistrictCont& dc, NBEdgeCont& ec, NBTrafficLightLogicCont& tlc) {
    for (NodeClusters::iterator i = clusters.begin(); i != clusters.end(); ++i) {
        std::set<NBNode*> cluster = *i;
        assert(cluster.size() > 1);
        Position pos;
        bool setTL;
        std::string id;
        TrafficLightType type;
        analyzeCluster(cluster, id, pos, setTL, type);
        if (!insert(id, pos)) {
            // should not fail
            WRITE_WARNING("Could not join junctions " + id);
            continue;
        }
        NBNode* newNode = retrieve(id);
        if (setTL) {
            NBTrafficLightDefinition* tlDef = new NBOwnTLDef(id, newNode, 0, type);
            if (!tlc.insert(tlDef)) {
                // actually, nothing should fail here
                delete tlDef;
                throw ProcessError("Could not allocate tls '" + id + "'.");
            }
        }
        // collect edges
        std::set<NBEdge*> allEdges;
        for (std::set<NBNode*>::const_iterator j = cluster.begin(); j != cluster.end(); ++j) {
            const EdgeVector& edges = (*j)->getEdges();
            allEdges.insert(edges.begin(), edges.end());
        }

        // remap and remove edges which are completely within the new intersection
        for (std::set<NBEdge*>::iterator j = allEdges.begin(); j != allEdges.end();) {
            NBEdge* e = (*j);
            NBNode* from = e->getFromNode();
            NBNode* to = e->getToNode();
            if (cluster.count(from) > 0 && cluster.count(to) > 0) {
                for (std::set<NBEdge*>::iterator l = allEdges.begin(); l != allEdges.end(); ++l) {
                    if (e != *l) {
                        (*l)->replaceInConnections(e, e->getConnections());
                    }
                }
                ec.erase(dc, e);
                allEdges.erase(j++); // erase does not invalidate the other iterators
            } else {
                ++j;
            }
        }

        // remap edges which are incoming / outgoing
        for (std::set<NBEdge*>::iterator j = allEdges.begin(); j != allEdges.end(); ++j) {
            NBEdge* e = (*j);
            std::vector<NBEdge::Connection> conns = e->getConnections();
            const bool outgoing = cluster.count(e->getFromNode()) > 0;
            NBNode* from = outgoing ? newNode : e->getFromNode();
            NBNode* to   = outgoing ? e->getToNode() : newNode;
            e->reinitNodes(from, to);
            // re-add connections which previously existed and may still valid.
            // connections to removed edges will be ignored
            for (std::vector<NBEdge::Connection>::iterator k = conns.begin(); k != conns.end(); ++k) {
                e->addLane2LaneConnection((*k).fromLane, (*k).toEdge, (*k).toLane, NBEdge::L2L_USER, false, (*k).mayDefinitelyPass);
            }
        }
        // remove original nodes
        registerJoinedCluster(cluster);
        for (std::set<NBNode*>::const_iterator j = cluster.begin(); j != cluster.end(); ++j) {
            erase(*j);
        }
    }
}
void
NBNodeCont::removeIsolatedRoads(NBDistrictCont& dc, NBEdgeCont& ec, NBTrafficLightLogicCont& tc) {
    UNUSED_PARAMETER(tc);
    // Warn of isolated edges, i.e. a single edge with no connection to another edge
    int edgeCounter = 0;
    const std::vector<std::string>& edgeNames = ec.getAllNames();
    for (std::vector<std::string>::const_iterator it = edgeNames.begin(); it != edgeNames.end(); ++it) {
        // Test whether this node starts at a dead end, i.e. it has only one adjacent node
        // to which an edge exists and from which an edge may come.
        NBEdge* e = ec.retrieve(*it);
        if (e == 0) {
            continue;
        }
        NBNode* from = e->getFromNode();
        const EdgeVector& outgoingEdges = from->getOutgoingEdges();
        if (outgoingEdges.size() != 1) {
            // At this node, several edges or no edge start; so, this node is no dead end.
            continue;
        }
        const EdgeVector& incomingEdges = from->getIncomingEdges();
        if (incomingEdges.size() > 1) {
            // At this node, several edges end; so, this node is no dead end.
            continue;
        } else if (incomingEdges.size() == 1) {
            NBNode* fromNodeOfIncomingEdge = incomingEdges[0]->getFromNode();
            NBNode* toNodeOfOutgoingEdge = outgoingEdges[0]->getToNode();
            if (fromNodeOfIncomingEdge != toNodeOfOutgoingEdge) {
                // At this node, an edge ends which is not the inverse direction of
                // the starting node.
                continue;
            }
        }
        // Now we know that the edge e starts a dead end.
        // Next we test if the dead end is isolated, i.e. does not lead to a junction
        bool hasJunction = false;
        EdgeVector road;
        NBEdge* eOld = 0;
        NBNode* to;
        std::set<NBNode*> adjacentNodes;
        do {
            road.push_back(e);
            eOld = e;
            from = e->getFromNode();
            to = e->getToNode();
            const EdgeVector& outgoingEdgesOfToNode = to->getOutgoingEdges();
            const EdgeVector& incomingEdgesOfToNode = to->getIncomingEdges();
            adjacentNodes.clear();
            for (EdgeVector::const_iterator itOfOutgoings = outgoingEdgesOfToNode.begin(); itOfOutgoings != outgoingEdgesOfToNode.end(); ++itOfOutgoings) {
                if ((*itOfOutgoings)->getToNode() != from        // The back path
                        && (*itOfOutgoings)->getToNode() != to   // A loop / dummy edge
                   ) {
                    e = *itOfOutgoings; // Probably the next edge
                }
                adjacentNodes.insert((*itOfOutgoings)->getToNode());
            }
            for (EdgeVector::const_iterator itOfIncomings = incomingEdgesOfToNode.begin(); itOfIncomings != incomingEdgesOfToNode.end(); ++itOfIncomings) {
                adjacentNodes.insert((*itOfIncomings)->getFromNode());
            }
            adjacentNodes.erase(to);  // Omit loops
            if (adjacentNodes.size() > 2) {
                hasJunction = true;
            }
        } while (!hasJunction && eOld != e);
        if (!hasJunction) {
            edgeCounter +=  int(road.size());
            std::string warningString = "Removed a road without junctions: ";
            for (EdgeVector::iterator roadIt = road.begin(); roadIt != road.end(); ++roadIt) {
                if (roadIt == road.begin()) {
                    warningString += (*roadIt)->getID();
                } else {
                    warningString += ", " + (*roadIt)->getID();
                }

                NBNode* fromNode = (*roadIt)->getFromNode();
                NBNode* toNode = (*roadIt)->getToNode();
                ec.erase(dc, *roadIt);
                if (fromNode->getIncomingEdges().size() == 0 && fromNode->getOutgoingEdges().size() == 0) {
                    // Node is empty; can be removed
                    erase(fromNode);
                }
                if (toNode->getIncomingEdges().size() == 0 && toNode->getOutgoingEdges().size() == 0) {
                    // Node is empty; can be removed
                    erase(toNode);
                }
            }
            WRITE_WARNING(warningString);
        }
    }
    if (edgeCounter > 0 && !OptionsCont::getOptions().getBool("remove-edges.isolated")) {
        WRITE_WARNING("Detected isolated roads. Use the option --remove-edges.isolated to get a list of all affected edges.");
    }
}