#ifndef DIGRAPH_H_
#define DIGRAPH_H_

#include "graph.h"

#include <algorithm>
#include <ranges>

namespace graph {

template<typename T>
class Digraph : public Graph<T> {
public:
  Digraph() = default;

  Digraph(std::map<T, std::set<T>> digraph);

  // Reverse graph directions
  Digraph<T> reverse();
};

template<typename T>
Digraph<T>::Digraph(std::map<T, std::set<T>> digraph) {
  Graph<T>::adjMatrix = digraph;
  auto kv = std::views::keys(Graph<T>::adjMatrix);
  Graph<T>::vertices = std::set<T>{ kv.begin(), kv.end() };
}

template<typename T>
Digraph<T> Digraph<T>::reverse() {
  std::map<T, std::set<T>> revMatrix;
  
  for (const auto& v : Graph<T>::adjMatrix) {
    for (const auto& u : v.second) {
      revMatrix[u].insert(v.first);
    }
  }

  return revMatrix;
}

} // namespace graph

#endif