/*   
  tie-engraver.cc --  implement Tie_engraver
  
  source file of the GNU LilyPond music typesetter
  
  (c) 1998--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
  
 */

#include "command-request.hh"
#include "rhythmic-head.hh"
#include "musical-request.hh"
#include "tie.hh"
#include "translator-group.hh"
#include "spanner.hh"
#include "tie-column.hh"
#include "pqueue.hh"
#include "engraver.hh"
#include "item.hh"
#include "grob-pitch-tuple.hh"


/**
   Manufacture ties.  Acknowledge noteheads, and put them into a
   priority queue. If we have a Tie_req, connect the notes that finish
   just at this time, and note that start at this time.

   TODO: junk the pq; the PQ is overkill if we assume that no
   different durations occur in parallel.

   TODO: Remove the dependency on musical info. We should tie on the
   basis of position and duration-log of the heads (not of the reqs).

*/
class Tie_engraver : public Engraver
{
  PQueue<Grob_pitch_tuple> past_notes_pq_;
  Moment end_mom_;
  Moment next_end_mom_;

  Tie_req *req_l_;
  Array<Grob_pitch_tuple> now_heads_;
  Array<Grob_pitch_tuple> stopped_heads_;
  Link_array<Grob> tie_p_arr_;

  Spanner * tie_column_p_;
  
  void set_melisma (bool);
  
protected:
  virtual void start_translation_timestep ();
  virtual void stop_translation_timestep ();
  virtual void acknowledge_grob (Grob_info);
  virtual bool try_music (Music*);
  virtual void create_grobs ();
  void typeset_tie (Grob*);
public:
  TRANSLATOR_DECLARATIONS(Tie_engraver);
};



Tie_engraver::Tie_engraver ()
{
  req_l_ = 0;
  tie_column_p_ = 0;
}


bool
Tie_engraver::try_music (Music *m)
{
  if (Tie_req * c = dynamic_cast<Tie_req*> (m))
    {
      /*      if (end_mom_ > now_mom ())
       return false;
      */
      req_l_ = c;
      SCM m = get_property ("automaticMelismata");
      bool am = gh_boolean_p (m) &&gh_scm2bool (m);
      if (am)
	{
	  set_melisma (true);
	}
      return true;
    }
  return false;
}

void
Tie_engraver::set_melisma (bool m)
{
  daddy_trans_l_->set_property ("tieMelismaBusy", m ? SCM_BOOL_T : SCM_BOOL_F);
}

void
Tie_engraver::acknowledge_grob (Grob_info i)
{
  if (Rhythmic_head::has_interface (i.grob_l_))
    {
      Note_req * m = dynamic_cast<Note_req* > (i.req_l_);
      if (!m)
	return;
      now_heads_.push (Grob_pitch_tuple (i.grob_l_, m, now_mom () + m->length_mom ()));
    }
}


void
Tie_engraver::create_grobs ()
{
  if (req_l_)
    {
      now_heads_.sort (Grob_pitch_tuple::pitch_compare);
      stopped_heads_.sort (Grob_pitch_tuple::pitch_compare);

      SCM head_list = SCM_EOL;
      
      int j = stopped_heads_.size ()-1;
      int i = now_heads_.size ()-1;

      while (i >= 0 && j >=0)
	{
	  int comp
	    = Pitch::compare (now_heads_[i].pitch_,
			      stopped_heads_[j].pitch_);

	  if (comp)
	    {
 (comp < 0) ? j -- : i--;
	      continue;
	    }
	  else
	    {
	      head_list  = gh_cons (gh_cons (stopped_heads_[j].head_l_->self_scm (),
					     now_heads_[i].head_l_->self_scm ()),
				    head_list);

	      past_notes_pq_. insert (now_heads_[i]);
	      now_heads_.del (i);
	      stopped_heads_.del (j);
	      i--;
	      j--;
	    }
	}

      SCM basic = get_property ("Tie");
      SCM sparse = get_property ("sparseTies");
      if (to_boolean (sparse))
	{
	  int i = scm_ilength (head_list);

	  if (!i)
	    return;
	  
	  SCM pair = scm_list_ref (head_list, gh_int2scm (i/2));
	  
	  Spanner * p = new Spanner (basic);

	  Tie::set_interface (p);
	  Tie::set_head (p,LEFT, dynamic_cast<Item*> (unsmob_grob (ly_car (pair))));
	  Tie::set_head (p,RIGHT, dynamic_cast<Item*> (unsmob_grob (ly_cdr (pair))));
	  
	  tie_p_arr_.push (p);
	  announce_grob (p, req_l_);
	}
      else for (SCM s = head_list; gh_pair_p (s); s = ly_cdr (s))
	{
	  Grob * p = new Spanner (basic);
	  Tie::set_interface (p);
	  
	  Tie::set_head (p, LEFT, dynamic_cast<Item*> (unsmob_grob (ly_caar (s))));
	  Tie::set_head (p, RIGHT, dynamic_cast<Item*> (unsmob_grob (ly_cdar (s))));
	  
	  tie_p_arr_.push (p);
	  announce_grob (p, req_l_);
	}

      if (tie_p_arr_.size () > 1 && !tie_column_p_)
	{
	  tie_column_p_ = new Spanner (get_property ("TieColumn"));
	  Tie_column::set_interface (tie_column_p_);
	  for (int i = tie_p_arr_.size (); i--;)
	    Tie_column::add_tie (tie_column_p_,tie_p_arr_ [i]);
	  announce_grob (tie_column_p_, 0);
	}
    }
}


void
Tie_engraver::stop_translation_timestep ()
{
  req_l_ = 0;
  for (int i=0; i < now_heads_.size (); i++)
    {
      past_notes_pq_.insert (now_heads_[i]);
    }
  now_heads_.clear ();

  /*
    we don't warn for no ties, since this happens naturally when you
    use skipTypesetting.  */
  
  for (int i=0; i<  tie_p_arr_.size (); i++)
   {
      typeset_tie (tie_p_arr_[i]);
    }
  tie_p_arr_.clear ();
  if (tie_column_p_)
    {
      typeset_grob (tie_column_p_);
      tie_column_p_ =0;
    }
}

void
Tie_engraver::typeset_tie (Grob *her)
{
  if (! (Tie::head (her,LEFT) && Tie::head (her,RIGHT)))
    warning (_ ("lonely tie"));

  Direction d = LEFT;
  Drul_array<Grob *> new_head_drul;
  new_head_drul[LEFT] = Tie::head (her,LEFT);
  new_head_drul[RIGHT] = Tie::head (her,RIGHT);  
  do {
    if (!Tie::head (her,d))
      new_head_drul[d] = Tie::head (her, (Direction)-d);
  } while (flip (&d) != LEFT);

  index_set_cell (her->get_grob_property ("heads"), LEFT, new_head_drul[LEFT]->self_scm ());
  index_set_cell (her->get_grob_property ("heads"), RIGHT, new_head_drul[RIGHT]->self_scm ());

  typeset_grob (her);
}

void
Tie_engraver::start_translation_timestep ()
{
  SCM m = get_property ("automaticMelismata");
  if (to_boolean (m))
    {
      set_melisma (false);
    }

  Moment now = now_mom ();
  while (past_notes_pq_.size () && past_notes_pq_.front ().end_ < now)
    past_notes_pq_.delmin ();


  stopped_heads_.clear ();
  while (past_notes_pq_.size ()
	 && past_notes_pq_.front ().end_ == now)
    stopped_heads_.push (past_notes_pq_.get ());

}


ENTER_DESCRIPTION(Tie_engraver,
/* descr */       "Generate ties between noteheads of equal pitch.",
/* creats*/       "Tie TieColumn",
/* acks  */       "rhythmic-head-interface",
/* reads */       "sparseTies tieMelismaBusy",
/* write */       "");
