grid.hxx

/*
 * Copyright 2007-2025, RTE (https://www.rte-france.com)
 * See AUTHORS.txt
 * SPDX-License-Identifier: MPL-2.0
 * This file is part of Antares-Simulator,
 * Adequacy and Performance assessment for interconnected energy networks.
 *
 * Antares_Simulator is free software: you can redistribute it and/or modify
 * it under the terms of the Mozilla Public Licence 2.0 as published by
 * the Mozilla Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * Antares_Simulator 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
 * Mozilla Public Licence 2.0 for more details.
 *
 * You should have received a copy of the Mozilla Public Licence 2.0
 * along with Antares_Simulator. If not, see <https://opensource.org/license/mpl-2-0/>.
 */
#include <algorithm>
#include <list>
#include <numeric>
#include <stack>
#include <utility>
 
#include "antares/solver/constraints-builder/cbuilder.h"
#include "antares/solver/constraints-builder/grid.h"
 
using namespace Yuni;
 
namespace Antares::Graph
{
template<class NodeT>
Grid<NodeT>::Grid():
    inf(0)
{
}
 
template<class NodeT>
Grid<NodeT>::~Grid()
{
    for (auto i = pEdgesList.begin(); i != pEdgesList.end(); i++)
    {
        delete (*i);
    }
    for (auto i = pNodesList.begin(); i != pNodesList.end(); i++)
    {
        delete (*i);
    }
}
 
template<class NodeT>
typename Grid<NodeT>::NodeP Grid<NodeT>::addNode(NodeT& n, std::string id)
{
    auto nodeIT = std::find_if(pNodesList.begin(),
                               pNodesList.end(),
                               [&id](const NodeP& nodeP) -> bool
                               { return nodeP->getName() == id; });
 
    if (nodeIT == pNodesList.end())
    {
        NodeP newNode = new Graph::Node<NodeT>(&n);
        newNode->setName(id);
        pNodesList.push_back(newNode);
        return newNode;
    }
    else
    {
        return *nodeIT;
    }
}
 
template<class NodeT>
typename Grid<NodeT>::EdgeP Grid<NodeT>::addEdge(NodeP n1, NodeP n2, long weight)
{
    std::string s1(n1->getName());
    std::string s2(n2->getName());
    EdgeP edgePtr = findEdgeFromNodeNames(s1, s2);
    if (edgePtr == nullptr)
    {
        EdgeP newEdge = new Edge<NodeT>(n1, n2);
        inf += weight;
        newEdge->setWeight(weight);
 
        // add edge to the list
        pEdgesList.push_back(newEdge);
 
        // redefine inf
        inf += weight;
 
        // update adjency
        adjency[newEdge->getOrigin()].insert(std::make_pair(newEdge->getDestination(), newEdge));
        adjency[newEdge->getDestination()].insert(std::make_pair(newEdge->getOrigin(), newEdge));
 
        return newEdge;
    }
    else
    {
        return edgePtr;
    }
}
 
template<class NodeT>
uint Grid<NodeT>::getNumberOfConnectedComponents()
{
    // create union-find set
    MapNodes uf;
 
    for (auto i = pNodesList.begin(); i != pNodesList.end(); i++)
    {
        uf.insert(std::make_pair(*i, *i));
    }
 
    // algorithm
    for (auto i = pEdgesList.begin(); i != pEdgesList.end(); i++)
    {
        // if the two areas are not yet connected
        if (uf[(*i)->getOrigin()] != uf[(*i)->getDestination()])
        {
            // update uf
            NodeP cset(uf[(*i)->getDestination()]);
            for (auto j = pNodesList.begin(); j != pNodesList.end(); j++)
            {
                if (uf[*j] == cset)
                {
                    uf[*j] = uf[(*i)->getOrigin()];
                }
            }
        }
    }
 
    std::unordered_map<NodeP, bool> cVec;
    for (auto cIT = uf.begin(); cIT != uf.end(); cIT++)
    {
        cVec[cIT->second] = true;
    }
 
    return (uint)(cVec.size());
}
 
template<class NodeT>
void Grid<NodeT>::kruskal()
{
    // clear spanning tree
    pMinSpanningTree.clear();
 
    // create union-find set
    MapNodes uf;
 
    for (auto i = pNodesList.begin(); i != pNodesList.end(); i++)
    {
        uf.insert(std::make_pair(*i, *i));
    }
 
    // create temporary sorted vector of Link
    VectorEdgeP tempEdgesList = pEdgesList;
    std::stable_sort(tempEdgesList.begin(),
                     tempEdgesList.end(),
                     typename Graph::Edge<NodeT>::compareWeight());
 
    // algorithm
    for (auto i = tempEdgesList.begin(); i != tempEdgesList.end(); i++)
    {
        // if the two areas are not yet connected
        if (uf[(*i)->getOrigin()] != uf[(*i)->getDestination()])
        {
            pMinSpanningTree.push_back(*i);
 
            // update uf
            NodeP cset(uf[(*i)->getDestination()]);
            for (auto j = pNodesList.begin(); j != pNodesList.end(); j++)
            {
                if (uf[*j] == cset)
                {
                    uf[*j] = uf[(*i)->getOrigin()];
                }
            }
        }
    }
}
 
template<class NodeT>
bool Grid<NodeT>::buildMesh()
{
    // build the minimum spanning tree
    kruskal();
 
    if (pMinSpanningTree.empty())
    {
        return false;
    }
 
    // clear the spanning cycle base
    pMesh.clear();
    meshIndexMatrix.clear();
 
    // initialization
    std::vector<EdgeP> linksToBeAdded;
    for (auto i = pEdgesList.begin(); i != pEdgesList.end(); i++)
    {
        // check if the link already belong to the skeleton
        if (std::find(pMinSpanningTree.begin(), pMinSpanningTree.end(), (*i))
            == pMinSpanningTree.end())
        {
            linksToBeAdded.push_back(*i);
        }
    }
 
    std::vector<EdgeIncidence> incidenceMatrix(linksToBeAdded.size());
    for (uint i = 0; i < linksToBeAdded.size(); i++)
    {
        incidenceMatrix[i] = getIncidenceVector(linksToBeAdded[i]);
    }
 
    for (uint i = 0; i < linksToBeAdded.size(); i++)
    {
        logs.info() << "Searching basis (loop " << i + 1 << "/" << linksToBeAdded.size() << ")";
        // build the graph with two copies (+/-) for each node and edge
        Grid<NodeT> polarisedDuplicate;
        getDuplicatedGrid(polarisedDuplicate);
        VectorEdgeP v = getEdgeVectorFromIncidence(incidenceMatrix[i]);
        VectorEdgeP Ci;
        VectorNodeP adjacentNodes;
        // retrait des arêtes (u,v) qui sont dans Ei et remplacement dans le graphe dupliqué
        // par(u+,v-) et (u-,v+)
        for (uint j = 0; j < v.size(); j++)
        {
            if (std::find(adjacentNodes.begin(), adjacentNodes.end(), v[j]->getOrigin())
                == adjacentNodes.end())
            {
                adjacentNodes.push_back(v[j]->getOrigin());
            }
            if (std::find(adjacentNodes.begin(), adjacentNodes.end(), v[j]->getDestination())
                == adjacentNodes.end())
            {
                adjacentNodes.push_back(v[j]->getDestination());
            }
 
            EdgeP ei = polarisedDuplicate.findEdgeFromNodeNames(v[j]->getOrigin()->getName() + "+",
                                                                v[j]->getDestination()->getName()
                                                                  + "+");
 
            NodeP ni1 = polarisedDuplicate.findNodeFromName(v[j]->getOrigin()->getName() + "+");
            NodeP ni2 = polarisedDuplicate.findNodeFromName(v[j]->getDestination()->getName()
                                                            + "-");
 
            polarisedDuplicate.addEdge(ni1, ni2, ei->getWeight());
            polarisedDuplicate.removeEdge(ei);
 
            ei = polarisedDuplicate.findEdgeFromNodeNames(v[j]->getOrigin()->getName() + "-",
                                                          v[j]->getDestination()->getName() + "-");
 
            ni1 = polarisedDuplicate.findNodeFromName(v[j]->getOrigin()->getName() + "-");
            ni2 = polarisedDuplicate.findNodeFromName(v[j]->getDestination()->getName() + "+");
 
            polarisedDuplicate.addEdge(ni1, ni2, ei->getWeight());
            polarisedDuplicate.removeEdge(ei);
        }
 
        v = polarisedDuplicate.twoLevelPath(adjacentNodes);
 
        Ci.clear();
        std::vector<int> edgeIndices;
        for (typename VectorEdgeP::iterator e = v.begin(); e != v.end(); e++)
        {
            auto name1 = (*e)->getOrigin()->getName();
            name1 = name1.substr(0, name1.length() - 1);
            auto name2 = (*e)->getDestination()->getName();
            name2 = name2.substr(0, name2.length() - 1);
            EdgeP ei = findEdgeFromNodeNames(name1, name2);
            Ci.push_back(ei);
 
            auto eIT = std::find(pEdgesList.begin(), pEdgesList.end(), ei);
            int pos = (int)std::distance(pEdgesList.begin(), eIT);
            edgeIndices.push_back(pos);
        }
 
        pMesh.push_back(Ci);
        EdgeIncidence I = getIncidenceVector(Ci);
        meshIndexMatrix.push_back(edgeIndices);
        // remplacement par la différence symétrique des des jeux d'arêtes
        for (uint j = i + 1; j < linksToBeAdded.size(); j++)
        {
            if (incidenceInnerProduct(I, incidenceMatrix[j]) == 1)
            {
                incidenceMatrix[j] = incidenceXOR(incidenceMatrix[i], incidenceMatrix[j]);
            }
        }
    }
 
    return true;
}
 
template<class NodeT>
bool Grid<NodeT>::getDuplicatedGrid(Grid<NodeT>& grid)
{
    // duplicate nodes
    for (typename VectorNodeP::iterator node = pNodesList.begin(); node != pNodesList.end(); node++)
    {
        { //+
            grid.addNode((*(*node)->nodeProperties), (*node)->getName() + "+");
        }
 
        { //-
            grid.addNode((*(*node)->nodeProperties), (*node)->getName() + "-");
        }
    }
 
    // Duplicate edges
    for (typename VectorEdgeP::iterator e = pEdgesList.begin(); e != pEdgesList.end(); e++)
    {
        { //+
            auto nodeOrigIT = std::find_if(grid.pNodesList.begin(),
                                           grid.pNodesList.end(),
                                           [&e](const NodeP& nodeP) -> bool {
                                               return nodeP->getName()
                                                      == (*e)->getOrigin()->getName() + "+";
                                           });
 
            auto nodeDestIT = std::find_if(grid.pNodesList.begin(),
                                           grid.pNodesList.end(),
                                           [&e](const NodeP& nodeP) -> bool {
                                               return nodeP->getName()
                                                      == (*e)->getDestination()->getName() + "+";
                                           });
 
            grid.addEdge(*nodeOrigIT, *nodeDestIT, (*e)->getWeight());
        }
 
        { //-
            auto nodeOrigIT = std::find_if(grid.pNodesList.begin(),
                                           grid.pNodesList.end(),
                                           [&e](const NodeP& nodeP) -> bool {
                                               return nodeP->getName()
                                                      == (*e)->getOrigin()->getName() + "-";
                                           });
 
            auto nodeDestIT = std::find_if(grid.pNodesList.begin(),
                                           grid.pNodesList.end(),
                                           [&e](const NodeP& nodeP) -> bool {
                                               return nodeP->getName()
                                                      == (*e)->getDestination()->getName() + "-";
                                           });
 
            grid.addEdge(*nodeOrigIT, *nodeDestIT, (*e)->getWeight());
        }
    }
    return true;
}
 
template<class NodeT>
bool Grid<NodeT>::cloneGrid(Grid<NodeT>& grid)
{
    // duplicate nodes
    for (typename VectorNodeP::iterator node = pNodesList.begin(); node != pNodesList.end(); node++)
    {
        {
            grid.addNode((*(*node)->nodeProperties), (*node)->getName());
        }
    }
 
    // duplicate edges
    for (typename VectorEdgeP::iterator e = pEdgesList.begin(); e != pEdgesList.end(); e++)
    {
        { //+
            auto nodeOrigIT = std::find_if(grid.pNodesList.begin(),
                                           grid.pNodesList.end(),
                                           [&e](const NodeP& nodeP) -> bool {
                                               return nodeP->getName()
                                                      == (*e)->getOrigin()->getName();
                                           });
 
            auto nodeDestIT = std::find_if(grid.pNodesList.begin(),
                                           grid.pNodesList.end(),
                                           [&e](const NodeP& nodeP) -> bool {
                                               return nodeP->getName()
                                                      == (*e)->getDestination()->getName();
                                           });
 
            grid.addEdge(*nodeOrigIT, *nodeDestIT, (*e)->getWeight());
        }
    }
    return true;
}
 
template<class NodeT>
typename Grid<NodeT>::VectorEdgeP Grid<NodeT>::twoLevelPath(VectorNodeP vN)
{
    VectorEdgeP SP, minSP;
    double minLength = DBL_MAX, length;
    for (typename VectorNodeP::iterator n = vN.begin(); n != vN.end(); n++)
    {
        SP = findShortestPath(findNodeFromName((*n)->getName() + "+"),
                              findNodeFromName((*n)->getName() + "-"));
        length = std::accumulate(SP.begin(),
                                 SP.end(),
                                 (long)0,
                                 typename Graph::Edge<NodeT>::addpWeight());
        if (length < minLength)
        {
            minLength = length;
            minSP = SP;
        }
    }
 
    return minSP;
}
 
template<class NodeT>
typename Grid<NodeT>::VectorEdgeP Grid<NodeT>::findShortestPath(NodeP node1, NodeP node2) const
{
    assert(node1 != node2);
 
    // Dijkstra (lots of computation which could be optimised)
    // initialization
    std::map<NodeP, double> dist;
    std::map<NodeP, NodeP> prev;
 
    // decorate to avoid warnings at compile
    [[maybe_unused]] bool checkNode1(false), checkNode2(false);
    VectorNodeP nodes = pNodesList;
 
    for (auto i = nodes.begin(); i != nodes.end(); i++)
    {
        dist[(*i)] = inf;
        prev[(*i)] = 0;
        if ((*i) == node1)
        {
            checkNode1 = true;
        }
        else if ((*i) == node2)
        {
            checkNode2 = true;
        }
    }
    assert(checkNode1 && checkNode2);
    dist[node1] = 0;
    // search for shortest path
    bool targetFound(0);
    while (!targetFound)
    {
        // look for closest element u belonging in nodes
        std::pair<Grid::NodeP, double> u(nullptr, inf - 1);
        typename Grid::VectorNodeP::iterator ui;
        for (auto i = nodes.begin(); i != nodes.end(); i++)
        {
            if (dist[(*i)] < u.second)
            {
                u.first = (*i);
                u.second = dist[(*i)];
                ui = i;
            }
        }
 
        // see if destination node has been f
        if (u.first == node2)
        {
            targetFound = true;
            break;
        }
 
        // remove u from the list of nodes
        nodes.erase(ui);
 
        // update the neighoubours of u
        for (auto i = adjency.at(u.first).begin(); i != adjency.at(u.first).end(); i++)
        {
            if (i->second == nullptr)
            {
                assert(0);
            }
 
            if ((u.second + i->second->getWeight()) < dist[i->first])
            {
                dist[i->first] = u.second + i->second->getWeight();
                prev[i->first] = u.first;
            }
        }
    }
 
    // rebuild path
    Grid::VectorEdgeP path;
    Grid::NodeP currentNode = node2;
 
    while (prev[currentNode] != nullptr)
    {
        path.push_back(adjency.at(currentNode).at(prev[currentNode]));
        currentNode = prev[currentNode];
    }
 
    return path;
}
 
} // namespace Antares::Graph