view pertrackaccumulator.h @ 462:f689510baaf4 api-inversion

Simplify audioDB::query_loop_points.

Using the new functions audiodb_track_id_datum() and
audiodb_datum_qpointers(), much of the body of the method disappears.
Of course, we've probably introduced some inefficiencies and extra
memory copies, but I'm fairly sure that this method is going to be
dominated by disk i/o time anyway, so it doesn't matter.

template <class T> class PerTrackAccumulator : public Accumulator {
public:
  PerTrackAccumulator(unsigned int pointNN, unsigned int trackNN);
  ~PerTrackAccumulator();
  void add_point(adb_result_t *r);
  adb_query_results_t *get_points();
private:
  unsigned int pointNN;
  unsigned int trackNN;
  std::map<adb_result_t, std::priority_queue< adb_result_t, std::vector<adb_result_t>, T > *, adb_result_key_lt> *queues;
  std::set< adb_result_t, adb_result_triple_lt > *set;
};

template <class T> PerTrackAccumulator<T>::PerTrackAccumulator(unsigned int pointNN, unsigned int trackNN)
  : pointNN(pointNN), trackNN(trackNN), queues(0), set(0) {
  queues = new std::map<adb_result_t, std::priority_queue< adb_result_t, std::vector<adb_result_t>, T > *, adb_result_key_lt>;
  set = new std::set< adb_result_t, adb_result_triple_lt >;
}

template <class T> PerTrackAccumulator<T>::~PerTrackAccumulator() {
  if(queues) {
    typename std::map< adb_result_t, std::priority_queue< adb_result_t, std::vector< adb_result_t >, T > *, adb_result_key_lt>::iterator it;
    for(it = queues->begin(); it != queues->end(); it++) {
      delete (*it).second;
    }
    delete queues;
  }
  if(set) {
    delete set;
  }
}

template <class T> void PerTrackAccumulator<T>::add_point(adb_result_t *r) {
  if(!isnan(r->dist)) {
    if(set->find(*r) == set->end()) {
      set->insert(*r);

      typename std::map< adb_result_t, std::priority_queue< adb_result_t, std::vector< adb_result_t >, T > *, adb_result_key_lt>::iterator it;
      std::priority_queue< adb_result_t, std::vector< adb_result_t >, T > *queue;
      it = queues->find(*r);
      if(it == queues->end()) {
        queue = new std::priority_queue< adb_result_t, std::vector< adb_result_t >, T >;
        (*queues)[*r] = queue;
      } else {
        queue = (*it).second;
      }

      queue->push(*r);
      if(queue->size() > pointNN) {
        queue->pop();
      }
    }
  }
}

template <class T> adb_query_results_t *PerTrackAccumulator<T>::get_points() {
  typename std::map< adb_result_t, std::vector< adb_result_t >, adb_result_key_lt> points;
  typename std::priority_queue< adb_result_t, std::vector< adb_result_t >, T> queue;
  typename std::map< adb_result_t, std::priority_queue< adb_result_t, std::vector< adb_result_t >, T > *, adb_result_key_lt>::iterator it;

  unsigned int size = 0;
  for(it = queues->begin(); it != queues->end(); it++) {
    unsigned int n = ((*it).second)->size();
    std::vector<adb_result_t> v;
    adb_result_t r;
    double dist = 0;
    for(unsigned int k = 0; k < n; k++) {
      r = ((*it).second)->top();
      dist += r.dist;
      v.push_back(r);
      ((*it).second)->pop();
    }
    points[r] = v;
    dist /= n;
    size += n;
    r.dist = dist;
    /* I will burn in hell */
    r.ipos = n;
    queue.push(r);
    if(queue.size() > trackNN) {
      size -= queue.top().ipos;
      queue.pop();
    }
  }

  adb_query_results_t *r = (adb_query_results_t *) malloc(sizeof(adb_query_results_t));
  adb_result_t *rs = (adb_result_t *) calloc(size, sizeof(adb_result_t));
  r->nresults = size;
  r->results = rs;
  
  unsigned int k = 0;
  while(queue.size() > 0) {
    std::vector<adb_result_t> v = points[queue.top()];
    queue.pop();
    while(v.size() > 0) {
      rs[k++] = v.back();
      v.pop_back();
    }
  }
  return r;
}