#ifndef SCC_H_
#define SCC_H_

#include "digraph.h"

#include <algorithm>
#include <functional>

namespace graph {

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

  SCC(std::map<T, std::set<T>> G, T id) : Digraph<T>(G), id(id) { normalize(); }

  SCC(Digraph<T> G, T id) : id(id) { normalize(); }

  // Return true if v is part of this SCC
  bool member(const T& v);

  // Representative vertex of this SCC
  T id;

  bool operator==(const SCC& o) const;
private:
  // Erase all edges that include vertices outside this SCC
  void normalize();
};

template<typename T>
void SCC<T>::normalize() {
  for (const auto& u : this->vertices()) {
    for (const auto& v : this->adjMatrix[u]) {
      if (!this->adjMatrix.count(v)) {
        this->adjMatrix[u].erase(v);
        this->adjMatrix.erase(v);
      }
    }
  }
}

template<typename T>
bool SCC<T>::member(const T& v) {
  const auto& V = this->vertices();
  return std::find(V.begin(), V.end(), v) != V.end();
}

template<typename T>
bool SCC<T>::operator==(const SCC& o) const{
  return id == o.id;
}

}; // namespace graph

#endif