#include <iostream>
#include <cmath>
#include "nlsr_lsdb.hpp"
#include "nlsr_rtc.hpp"
#include "nlsr_map.hpp"
#include "nlsr_lsa.hpp"
#include "nlsr_nexthop.hpp"
#include "nlsr.hpp"

namespace nlsr
{

  using namespace std;

  void
  RoutingTableCalculator::allocateAdjMatrix()
  {
    adjMatrix = new double*[numOfRouter];
    for(int i = 0; i < numOfRouter; ++i)
    {
      adjMatrix[i] = new double[numOfRouter];
    }
  }

  void
  RoutingTableCalculator::initMatrix()
  {
    for(int i=0; i<numOfRouter; i++)
    {
      for(int j=0; j<numOfRouter; j++)
        adjMatrix[i][j]=0;
    }
  }

  void
  RoutingTableCalculator::makeAdjMatrix(Nlsr& pnlsr, Map pMap)
  {
    std::list<AdjLsa> adjLsdb=pnlsr.getLsdb().getAdjLsdb();
    for( std::list<AdjLsa>::iterator it=adjLsdb.begin();
         it!= adjLsdb.end() ; it++)
    {
      string linkStartRouter=(*it).getOrigRouter();
      int row=pMap.getMappingNoByRouterName(linkStartRouter);
      std::list<Adjacent> adl=(*it).getAdl().getAdjList();
      for( std::list<Adjacent>::iterator itAdl=adl.begin();
           itAdl!= adl.end() ; itAdl++)
      {
        string linkEndRouter=(*itAdl).getAdjacentName();
        int col=pMap.getMappingNoByRouterName(linkEndRouter);
        double cost=(*itAdl).getLinkCost();
        if ( (row >= 0 && row<numOfRouter) && (col >= 0 && col<numOfRouter) )
        {
          adjMatrix[row][col]=cost;
        }
      }
    }
  }

  void
  RoutingTableCalculator::printAdjMatrix()
  {
    for(int i=0; i<numOfRouter; i++)
    {
      for(int j=0; j<numOfRouter; j++)
        printf("%f ",adjMatrix[i][j]);
      printf("\n");
    }
  }

  void
  RoutingTableCalculator::adjustAdMatrix(int source, int link, double linkCost)
  {
    for ( int i = 0; i < numOfRouter; i++ )
    {
      if ( i == link )
      {
        adjMatrix[source][i]=linkCost;
      }
      else
      {
        adjMatrix[source][i]=0;
      }
    }
  }

  int
  RoutingTableCalculator::getNumOfLinkfromAdjMatrix(int sRouter)
  {
    int noLink=0;
    for(int i=0; i<numOfRouter; i++)
    {
      if ( adjMatrix[sRouter][i] > 0 )
      {
        noLink++;
      }
    }
    return noLink;
  }

  void
  RoutingTableCalculator::getLinksFromAdjMatrix(int *links,
      double *linkCosts, int source)
  {
    int j=0;
    for (int i=0; i <numOfRouter; i++)
    {
      if ( adjMatrix[source][i] > 0 )
      {
        links[j]=i;
        linkCosts[j]=adjMatrix[source][i];
        j++;
      }
    }
  }

  void
  RoutingTableCalculator::freeAdjMatrix()
  {
    for(int i = 0; i < numOfRouter; ++i)
    {
      delete [] adjMatrix[i];
    }
    delete [] adjMatrix;
  }


  void
  RoutingTableCalculator::allocateLinks()
  {
    links=new int[vNoLink];
  }

  void RoutingTableCalculator::allocateLinkCosts()
  {
    linkCosts=new double[vNoLink];
  }


  void
  RoutingTableCalculator::freeLinks()
  {
    delete [] links;
  }
  void
  RoutingTableCalculator::freeLinksCosts()
  {
    delete [] linkCosts;
  }

  void
  LinkStateRoutingTableCalculator::calculatePath(Map& pMap,
      RoutingTable& rt, Nlsr& pnlsr)
  {
    cout<<"LinkStateRoutingTableCalculator::calculatePath Called"<<endl;
    allocateAdjMatrix();
    initMatrix();
    makeAdjMatrix(pnlsr,pMap);
    cout<<pMap;
    printAdjMatrix();
    string routerName=pnlsr.getConfParameter().getRouterPrefix();
    int sourceRouter=pMap.getMappingNoByRouterName(routerName);
    int noLink=getNumOfLinkfromAdjMatrix(sourceRouter);
    allocateParent();
    allocateDistance();
    if ( pnlsr.getConfParameter().getMaxFacesPerPrefix() == 1 )
    {
      // Single Path
      doDijkstraPathCalculation(sourceRouter);
      // print all ls path -- debugging purpose
      printAllLsPath(sourceRouter);
      // update routing table
      addAllLsNextHopsToRoutingTable(pnlsr, rt, pMap, sourceRouter);
    }
    else
    {
      // Multi Path
      setNoLink(getNumOfLinkfromAdjMatrix(sourceRouter));
      allocateLinks();
      allocateLinkCosts();
      getLinksFromAdjMatrix(links, linkCosts, sourceRouter);
      for (int i=0 ; i < vNoLink; i++)
      {
        adjustAdMatrix(sourceRouter,links[i], linkCosts[i]);
        printAdjMatrix();
        doDijkstraPathCalculation(sourceRouter);
        // print all ls path -- debugging purpose
        printAllLsPath(sourceRouter);
        //update routing table
        addAllLsNextHopsToRoutingTable(pnlsr, rt, pMap, sourceRouter);
      }
      freeLinks();
      freeLinksCosts();
    }
    freeParent();
    freeDistance();
    freeAdjMatrix();
  }

  void
  LinkStateRoutingTableCalculator::doDijkstraPathCalculation(int sourceRouter)
  {
    int i;
    int v,u;
    int *Q=new int[numOfRouter];
    int head=0;
    /* Initiate the Parent */
    for (i = 0 ; i < numOfRouter; i++)
    {
      parent[i]=EMPTY_PARENT;
      distance[i]=INF_DISTANCE;
      Q[i]=i;
    }
    if ( sourceRouter != NO_MAPPING_NUM )
    {
      distance[sourceRouter]=0;
      sortQueueByDistance(Q,distance,head,numOfRouter);
      while (head < numOfRouter )
      {
        u=Q[head];
        if(distance[u] == INF_DISTANCE)
        {
          break;
        }
        for(v=0 ; v <numOfRouter; v++)
        {
          if( adjMatrix[u][v] > 0 )
          {
            if ( isNotExplored(Q,v,head+1,numOfRouter) )
            {
              if( distance[u] + adjMatrix[u][v] <  distance[v])
              {
                distance[v]=distance[u] + adjMatrix[u][v] ;
                parent[v]=u;
              }
            }
          }
        }
        head++;
        sortQueueByDistance(Q,distance,head,numOfRouter);
      }
    }
    delete [] Q;
  }

  void
  LinkStateRoutingTableCalculator::addAllLsNextHopsToRoutingTable(Nlsr& pnlsr,
      RoutingTable& rt, Map& pMap, int sourceRouter)
  {
    cout<<"LinkStateRoutingTableCalculator::addAllNextHopsToRoutingTable Called";
    cout<<endl;
    for(int i=0; i < numOfRouter ; i++)
    {
      if ( i!= sourceRouter )
      {
        int nextHopRouter=getLsNextHop(i,sourceRouter);
        if ( nextHopRouter != NO_NEXT_HOP )
        {
          double routeCost=distance[i];
          string nextHopRouterName=
            pMap.getRouterNameByMappingNo(nextHopRouter);
          int nxtHopFace=
            pnlsr.getAdl().getAdjacent(nextHopRouterName).getConnectingFace();
          cout<<"Dest Router: "<<pMap.getRouterNameByMappingNo(i)<<endl;
          cout<<"Next hop Router: "<<nextHopRouterName<<endl;
          cout<<"Next hop Face: "<<nxtHopFace<<endl;
          cout<<"Route Cost: "<<routeCost<<endl;
          cout<<endl;
          // Add next hop to routing table
          NextHop nh(nxtHopFace,routeCost);
          rt.addNextHop(pMap.getRouterNameByMappingNo(i),nh);
        }
      }
    }
  }

  int
  LinkStateRoutingTableCalculator::getLsNextHop(int dest, int source)
  {
    int nextHop;
    while ( parent[dest] != EMPTY_PARENT )
    {
      nextHop=dest;
      dest=parent[dest];
    }
    if ( dest != source )
    {
      nextHop=NO_NEXT_HOP;
    }
    return nextHop;
  }

  void
  LinkStateRoutingTableCalculator::printAllLsPath(int sourceRouter)
  {
    cout<<"LinkStateRoutingTableCalculator::printAllLsPath Called"<<endl;
    cout<<"Source Router: "<<sourceRouter<<endl;
    for(int i=0; i < numOfRouter ; i++)
    {
      if ( i!= sourceRouter )
      {
        printLsPath(i);
        cout<<endl;
      }
    }
  }

  void
  LinkStateRoutingTableCalculator::printLsPath(int destRouter)
  {
    if (parent[destRouter] != EMPTY_PARENT )
    {
      printLsPath(parent[destRouter]);
    }
    cout<<" "<<destRouter;
  }

  void
  LinkStateRoutingTableCalculator::sortQueueByDistance(int *Q,
      double *dist,int start,int element)
  {
    for ( int i=start ; i < element ; i ++)
    {
      for( int j=i+1; j<element; j ++)
      {
        if (dist[Q[j]] < dist[Q[i]])
        {
          int tempU=Q[j];
          Q[j]=Q[i];
          Q[i]=tempU;
        }
      }
    }
  }

  int
  LinkStateRoutingTableCalculator::isNotExplored(int *Q,
      int u,int start, int element)
  {
    int ret=0;
    for(int i=start; i< element; i++)
    {
      if ( Q[i] == u )
      {
        ret=1;
        break;
      }
    }
    return ret;
  }

  void
  LinkStateRoutingTableCalculator::allocateParent()
  {
    parent=new int[numOfRouter];
  }

  void
  LinkStateRoutingTableCalculator::allocateDistance()
  {
    distance= new double[numOfRouter];
  }

  void
  LinkStateRoutingTableCalculator::freeParent()
  {
    delete [] parent;
  }

  void LinkStateRoutingTableCalculator::freeDistance()
  {
    delete [] distance;
  }


  void
  HypRoutingTableCalculator::calculatePath(Map& pMap,
      RoutingTable& rt, Nlsr& pnlsr)
  {
    makeAdjMatrix(pnlsr,pMap);
    string routerName=pnlsr.getConfParameter().getRouterPrefix();
    int sourceRouter=pMap.getMappingNoByRouterName(routerName);
    int noLink=getNumOfLinkfromAdjMatrix(sourceRouter);
    setNoLink(noLink);
    allocateLinks();
    allocateLinkCosts();
    getLinksFromAdjMatrix(links, linkCosts, sourceRouter);
    for(int i=0 ; i < numOfRouter ; ++i)
    {
      int k=0;
      if ( i != sourceRouter)
      {
        allocateLinkFaces();
        allocateDistanceToNeighbor();
        allocateDistFromNbrToDest();
        for(int j=0; j<vNoLink; j++)
        {
          string nextHopRouterName=pMap.getRouterNameByMappingNo(links[j]);
          int nextHopFace=
            pnlsr.getAdl().getAdjacent(nextHopRouterName).getConnectingFace();
          double distToNbr=getHyperbolicDistance(pnlsr,pMap,
                                                 sourceRouter,links[j]);
          double distToDestFromNbr=getHyperbolicDistance(pnlsr,
                                   pMap,links[j],i);
          if ( distToDestFromNbr >= 0 )
          {
            linkFaces[k] = nextHopFace;
            distanceToNeighbor[k] = distToNbr;
            distFromNbrToDest[k] = distToDestFromNbr;
            k++;
          }
        }
        addHypNextHopsToRoutingTable(pnlsr,pMap,rt,k,i);
        freeLinkFaces();
        freeDistanceToNeighbor();
        freeDistFromNbrToDest();
      }
    }
    freeLinks();
    freeLinksCosts();
    freeAdjMatrix();
  }

  void
  HypRoutingTableCalculator::addHypNextHopsToRoutingTable(Nlsr& pnlsr,Map& pMap,
      RoutingTable& rt, int noFaces, int dest)
  {
    for(int i=0 ; i < noFaces ; ++i)
    {
      string destRouter=pMap.getRouterNameByMappingNo(dest);
      NextHop nh(linkFaces[i],distFromNbrToDest[i]);
      rt.addNextHop(destRouter,nh);
      if( isDryRun == 1 )
      {
        rt.addNextHopToDryTable(destRouter,nh);
      }
    }
  }

  double
  HypRoutingTableCalculator::getHyperbolicDistance(Nlsr& pnlsr,
      Map& pMap, int src, int dest)
  {
    double distance=0.0;
    string srcRouterKey=pMap.getRouterNameByMappingNo(src)+"/3";
    string destRouterKey=pMap.getRouterNameByMappingNo(dest)+"/3";
    double srcRadius=(pnlsr.getLsdb().getCorLsa(srcRouterKey).first).getCorRadius();
    double srcTheta=(pnlsr.getLsdb().getCorLsa(srcRouterKey).first).getCorTheta();
    double destRadius=(pnlsr.getLsdb().getCorLsa(
                         destRouterKey).first).getCorRadius();
    double destTheta=(pnlsr.getLsdb().getCorLsa(destRouterKey).first).getCorTheta();
    double diffTheta = fabs (srcTheta - destTheta);
    if (diffTheta > MATH_PI)
    {
      diffTheta = 2 * MATH_PI - diffTheta;
    }
    if ( srcRadius != -1 && destRadius != -1 )
    {
      if (diffTheta == 0)
        distance = fabs (srcRadius - destRadius);
      else
        distance = acosh((cosh(srcRadius)*cosh(destRadius))-
                         (sinh(srcRadius)*sinh(destRadius)*cos(diffTheta)));
    }
    else
    {
      distance = -1;
    }
    return distance;
  }

  void
  HypRoutingTableCalculator::allocateLinkFaces()
  {
    linkFaces=new int[vNoLink];
  }

  void
  HypRoutingTableCalculator::allocateDistanceToNeighbor()
  {
    distanceToNeighbor=new double[vNoLink];
  }

  void
  HypRoutingTableCalculator::allocateDistFromNbrToDest()
  {
    distFromNbrToDest=new double[vNoLink];
  }

  void
  HypRoutingTableCalculator::freeLinkFaces()
  {
    delete [] linkFaces;
  }

  void
  HypRoutingTableCalculator::freeDistanceToNeighbor()
  {
    delete [] distanceToNeighbor;
  }

  void
  HypRoutingTableCalculator::freeDistFromNbrToDest()
  {
    delete [] distFromNbrToDest;
  }

}//namespace nlsr