void Dijkstra::calcPath(Workload& request, Graph& network, Stats& stats) {
bool pathFound=false;
bool exitLoop=false;
Element current; // current Element
Visited visited; // Visited list
Priority items; // priority queue
double previousCost=-1;
// 1. Get initial Start node
current.id=request.origin;
current.cost=0;
current.parent=request.origin; // TODO - possible problem...
items.push(current);
// 2. Loop until we have found a valid path
//while (!exitLoop && !items.empty()){
while (!items.empty()){
// Pop from the priority queue
current=items.top();
//std::cout<<"Current: "<<current.id<<" | Parent: "<<current.parent<< " | Goal:"<<request.destination<<std::endl;
items.pop(); // remove the element from the list
if (pathFound){
if(current.cost>previousCost){
exitLoop=true; // we want to exit the main loop
break;
}
}
previousCost=current.cost;
if (visited.find(current.id)==visited.end()) { //visited.find(current.id)==visited.end()
// Check if desired node
if (current.id==request.destination){ // Found the node!
pathFound=true;
//std::cout<<std::endl<<request.origin<<request.destination<<std::endl;
exitLoop=true; // TODO - remove me in future but currently bug when this is not here ????? map appears to be losing the parent of N for some weird reason..
}
else { // push the valid children which have bandwidth and are not allready visited onto the priority queue
network.begin(current.id,request.time);
while (!network.end()) {
pushChild(network.nextChild(),current,visited,items,network,request.time);
}
}
// Append the current node to the visited list
visited.insert(std::pair<char,Element>(current.id,current)); // be careful that the node is not allready in the visited list..possibly
}
}
// 3. Choose one valid path at random and backtrack -> calculate and append statistics...
if (pathFound){ // we have a valid path... -> backtrack to allocate resources
backTrack(request.origin,request.destination,request.time ,request.timeDuration ,visited,network,stats);
}
else {
//Path was impossible -> add blocked circuit
stats.addCircuit(false);
}
}
list<TPoint> reconstruire(Visited aMap,TPoint a)
{
if (aMap.find(make_pair(a.x,a.y))!=aMap.end())
{
TPoint z(aMap[make_pair(a.x,a.y)].first,aMap[make_pair(a.x,a.y)].second);
list<TPoint> p = reconstruire(aMap, z);
p.push_back(a);
return p;
}
else
{ list<TPoint> z;
z.push_back(a);
return z;
}
}
void Dijkstra::pushChild(char id, const Element& parentNode, Visited& visited, Priority& priority, Graph &network,double startTime) {
double cost= findCost(id,parentNode,network,startTime); // get the cost of the node...from the unique function
if (visited.find(id) == visited.end()) { // Element is not in visited map -> add it
//visited.insert(std::pair<char,Element>(id,Element(id,cost,parentNode.id))); - we are going to check if visited later
Element newnode;
newnode.id=id;newnode.cost=cost;newnode.parent=parentNode.id;
newnode.parents.push_back(parentNode.id);
priority.push(newnode);
}
else { // if the current cost is less than or equal to the elements cost then we may need to update the map
if (cost == visited.at(id).cost){ // we have found the node at the same cost... we need to put it as a parent as well
visited[id].parents.push_back(parentNode.id);
}
else if (cost < visited.at(id).cost){ // need to look at node again
visited[id].cost=cost;
priority.push(visited[id]);
}
}
}