/*
  tie-formatting-problem.cc -- implement Tie_formatting_problem

  source file of the GNU LilyPond music typesetter

  (c) 2005--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>

*/

#include "tie-formatting-problem.hh"

#include "paper-column.hh"
#include "bezier.hh" 
#include "directional-element-interface.hh"
#include "libc-extension.hh"
#include "misc.hh"
#include "note-head.hh"
#include "rhythmic-head.hh"
#include "spanner.hh" 
#include "staff-symbol-referencer.hh"
#include "stem.hh"
#include "tie-configuration.hh"
#include "tie.hh"
#include "warn.hh"


void
Tie_formatting_problem::print_ties_configuration (Ties_configuration const *ties)
{
  for (vsize i = 0; i < ties->size (); i++)
    {
      char const *man_pos = (specifications_[i].has_manual_position_) ? "(M)" : "";
      char const *man_dir = (specifications_[i].has_manual_dir_) ? "(M)" : "";
      char const *dir = (ties->at (i).dir_ == UP) ? "up" : "dn";
      
      printf ("(P%d%s, %s%s) ", ties->at (i).position_, man_pos, dir, man_dir);
    }
  printf ("\n");
}

Interval
Tie_formatting_problem::get_attachment (Real y, Drul_array<int> columns) const
{
  Interval attachments (0,0);
  Direction d = LEFT;
  do
    {
      Tuple2<int> key (columns[d], int (d));
      Chord_outline_map::const_iterator i (chord_outlines_.find (key));
      if (i == chord_outlines_.end ())
	programming_error ("Cannot find chord outline");
      else
	attachments[d] = i->second.height (y);
    }
  while (flip (&d) != LEFT);
  
  return attachments;
}

Tie_formatting_problem::Tie_formatting_problem()
{
  x_refpoint_ = 0;
}

Tie_formatting_problem::~Tie_formatting_problem ()
{
  for (Tie_configuration_map::const_iterator i (possibilities_.begin ());
       i != possibilities_.end (); i++)
    delete (*i).second;
}

void
Tie_formatting_problem::set_column_chord_outline (vector<Item*> bounds,
						  Direction dir,
						  int column_rank)
{
  Real staff_space = Staff_symbol_referencer::staff_space (bounds[0]);

  vector<Box> boxes;
  vector<Box> head_boxes;

  Grob *stem = 0;
  for (vsize i = 0; i < bounds.size (); i++)
    {
      Grob *head = bounds[i];
      if (!Note_head::has_interface (head))
	continue;
	  
      if (!stem)
	stem = unsmob_grob (head->get_object ("stem"));
	  
      Real p = Staff_symbol_referencer::get_position (head);
      Interval y ((p-1) * 0.5 * staff_space,
		  (p+1) * 0.5 * staff_space);

      Interval x = head->extent (x_refpoint_, X_AXIS);
      head_boxes.push_back (Box (x, y));
      boxes.push_back (Box (x, y));

      Grob *dots = Rhythmic_head::get_dots (head);
      if (dir == LEFT && dots)
	{
	  Interval x = dots->extent (x_refpoint_, X_AXIS);
	  int p = int (Staff_symbol_referencer::get_position (dots));

	  dot_positions_.insert (p);
	  dot_x_.unite (x);

	  Interval y (dots->extent (dots, Y_AXIS));
	  y.translate (p * staff_space * 0.5);
	  
	  boxes.push_back (Box (x, y));
	}
    }

  Tuple2<int> key (column_rank, int (dir));

  if (stem
      && !Stem::is_invisible (stem))
    {
      Interval x;
      x.add_point (stem->relative_coordinate (x_refpoint_, X_AXIS));
      x.widen (staff_space / 20); // ugh.
      Interval y;
      y.add_point (Stem::stem_end_position (stem) * staff_space * .5);

      Direction stemdir = get_grob_direction (stem);
      y.add_point (Stem::head_positions (stem)[-stemdir]
		   * staff_space * .5);

      boxes.push_back (Box (x, y));

      stem_extents_[key].unite (Box (x,y));

      if (dir == LEFT)
	{
	  Box flag_box = Stem::get_translated_flag (stem).extent_box ();
	  flag_box.translate( Offset (x[RIGHT], X_AXIS));
	  boxes.push_back (flag_box);
	}
    }
  else if (stem)
    {
      Grob *head = Stem::support_head (stem);

      /*
	In case of invisible stem, don't pass x-center of heads.
       */
      Real x_center = head->extent (x_refpoint_, X_AXIS).center ();
      Interval x_ext;
      x_ext[-dir] = x_center;
      Interval y_ext;
      for (vsize j = 0; j < head_boxes.size (); j++)
	y_ext.unite (head_boxes[j][Y_AXIS]);

      boxes.push_back (Box (x_ext, y_ext));
    }
  
  Direction updowndir = DOWN;
  do
    {
      Interval x;
      Interval y;
      if (head_boxes.size())
	{
	  Box b = boundary (head_boxes, updowndir, 0);
	  x = b[X_AXIS];
	  x[-dir] =  b[X_AXIS].linear_combination (-dir / 2);
	  y[-updowndir] = b[Y_AXIS][updowndir];
	  y[updowndir] = updowndir * infinity_f;
	}

      if (!x.is_empty ())
	boxes.push_back (Box (x, y));
    }
  while (flip (&updowndir) != DOWN);

  /* todo: the horizon_padding is somewhat arbitrary */
  chord_outlines_[key] = Skyline (boxes, 0.1, Y_AXIS, -dir);
  if (bounds[0]->break_status_dir ())
    {
      Real x = robust_relative_extent (bounds[0],  x_refpoint_, X_AXIS)[-dir];
      
      chord_outlines_[key].set_minimum_height (x);
    }
  else
    {
      Interval x;
      for (vsize j = 0; j < head_boxes.size (); j++)
	{
	  x.unite (head_boxes[j][X_AXIS]);
	}
      
      chord_outlines_[key].set_minimum_height (x[dir]);
    }

  head_extents_[key].set_empty ();
  for (vsize i = 0; i < head_boxes.size (); i++)
    {
      head_extents_[key].unite (head_boxes[i]);
    }
}

void
Tie_formatting_problem::set_chord_outline (vector<Item*> bounds,
					   Direction dir)

{
  vector<int> ranks;
  for (vsize i = 0; i < bounds.size (); i++)
    ranks.push_back (bounds[i]->get_column ()->get_rank ());

  vector_sort (ranks, less<int> ());
  uniq (ranks);

  for (vsize i = 0; i < ranks.size (); i++)
    {
      vector<Item*> col_items;
      for (vsize j = 0; j < bounds.size (); j ++)
	{
	  if (bounds[j]->get_column ()->get_rank () == ranks[i])
	    col_items.push_back (bounds[j]);
	}

      set_column_chord_outline (col_items, dir, ranks[i]);
    }
}
  


void
Tie_formatting_problem::from_tie (Grob *tie)
{
  vector<Grob*> ties;
  ties.push_back (tie);
  from_ties (ties);

  details_.from_grob (tie);
}

Grob *
Tie_formatting_problem::common_x_refpoint () const
{
  return x_refpoint_;
}

void
Tie_formatting_problem::from_ties (vector<Grob*> const &ties)
{
  if (ties.empty ())
    return;
  
  x_refpoint_ = ties[0];
  for (vsize i = 0; i < ties.size (); i++)
    {
      x_refpoint_ = dynamic_cast<Spanner*> (ties[i])->get_bound (LEFT)->common_refpoint (x_refpoint_, X_AXIS); 
      x_refpoint_ = dynamic_cast<Spanner*> (ties[i])->get_bound (RIGHT)->common_refpoint (x_refpoint_, X_AXIS); 
    }

  details_.from_grob (ties[0]);
  
  Direction d = LEFT;
  do
    {
      vector<Item*> bounds;
      
      for (vsize i = 0; i < ties.size (); i++)
	{
	  Item *it = dynamic_cast<Spanner*> (ties[i])->get_bound (d);
	  if (it->break_status_dir ())
	    {
	      Item *sep
		= dynamic_cast<Item*> (unsmob_grob (ties[i]->get_object ("separation-item")));
	      if (sep && sep->get_column () == it->get_column ())
		it = sep;
	    }
	  
	  bounds.push_back (it);
	}
      
      set_chord_outline (bounds, d);
    }
  while (flip (&d) != LEFT);


  for (vsize i = 0; i < ties.size (); i++)
    {
      Tie_specification spec;

      spec.get_tie_manual_settings (ties[i]);
      

      
      do
	{
	  spec.note_head_drul_[d] = Tie::head (ties[i], d);
	  spec.column_ranks_[d] = Tie::get_column_rank (ties[i], d);
	}
      while (flip (&d) != LEFT);
      specifications_.push_back (spec);
    }
}

void
Tie_formatting_problem::from_semi_ties (vector<Grob*> const &semi_ties, Direction head_dir)
{
  if (semi_ties.empty ())
    return;
  
  details_.from_grob (semi_ties[0]);
  vector<Item*> heads;

  int column_rank = -1;
  for (vsize i = 0; i < semi_ties.size (); i++)
    {
      Tie_specification spec;
      Item *head = unsmob_item (semi_ties[i]->get_object ("note-head"));
       
      if (!head)
	programming_error ("LV tie without head?!");

      if (head)
	{
	  spec.position_ = int (Staff_symbol_referencer::get_position (head));
	}

      spec.get_tie_manual_settings (semi_ties[i]);
      
      spec.note_head_drul_[head_dir] = head;
      column_rank = Tie::get_column_rank (semi_ties[i], head_dir);
      spec.column_ranks_ = Drul_array<int> (column_rank, column_rank);
      heads.push_back (head);
      specifications_.push_back (spec);
    }

  x_refpoint_ = semi_ties [0];
  for (vsize i = 0; i < semi_ties.size (); i++)
    x_refpoint_ = semi_ties[i]->common_refpoint (x_refpoint_, X_AXIS); 
  for (vsize i = 0; i < heads.size (); i++)
    x_refpoint_ = heads[i]->common_refpoint (x_refpoint_, X_AXIS); 

  set_chord_outline (heads, head_dir);

  Tuple2<int> head_key (column_rank, head_dir);
  Tuple2<int> open_key (column_rank, -head_dir);
  Real extremal = chord_outlines_[head_key].max_height ();

  chord_outlines_[open_key] = Skyline (head_dir);
  chord_outlines_[open_key].set_minimum_height (extremal - head_dir * 1.5);
}


Tie_specification
Tie_formatting_problem::get_tie_specification (int i) const
{
  return specifications_[i];
}


/*
  Return configuration, create it if necessary. 
*/
Tie_configuration*
Tie_formatting_problem::get_configuration (int pos, Direction dir, Drul_array<int> columns) const
{
  int key_components[] = {
    pos, dir, columns[LEFT], columns[RIGHT]
  };
  Tuple<int,4> key (key_components);
    
  Tie_configuration_map::const_iterator f = possibilities_.find (key);
  if (f != possibilities_.end ())
    {
      return (*f).second;
    }

  
  Tie_configuration *conf = generate_configuration (pos, dir, columns);
  ((Tie_formatting_problem*) this)->possibilities_[key] = conf;
  return conf;
}

Tie_configuration*
Tie_formatting_problem::generate_configuration (int pos, Direction dir,
						Drul_array<int> columns) const
{
  Tie_configuration *conf = new Tie_configuration;
  conf->position_ = pos;
  conf->dir_ = dir;
  
  conf->column_ranks_ = columns;
  
  Real y = conf->position_ * 0.5 * details_.staff_space_;

  bool y_tune = true;
  if (dot_positions_.find (pos) != dot_positions_.end ())
    {
      conf->delta_y_ += dir * 0.25 * details_.staff_space_;
      y_tune = false;
    }
  
  if (y_tune
      && max (fabs (get_head_extent (columns[LEFT], LEFT, Y_AXIS)[dir] - y),
	      fabs (get_head_extent (columns[RIGHT], RIGHT, Y_AXIS)[dir] - y)) < 0.25
      && !Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_, pos))
    {
      conf->delta_y_ =
	(get_head_extent (columns[LEFT], LEFT, Y_AXIS)[dir] - y)
	+ dir * details_.outer_tie_vertical_gap_;
    }

  if (y_tune)
    {
      conf->attachment_x_ = get_attachment (y + conf->delta_y_, conf->column_ranks_);
      Real h =  conf->height (details_);
      
      /*
	TODO:

	- should make sliding criterion, should flatten ties if

	- they're just the wrong (ie. touching line at top & bottom)
	size.
	
       */
      if (h < details_.intra_space_threshold_ * 0.5 * details_.staff_space_)
	{
	  if (!Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_, pos)
	      && abs (pos) < 2 * Staff_symbol_referencer::staff_radius (details_.staff_symbol_referencer_))
	    {
	      conf->center_tie_vertically (details_);
	    }
	  else if (Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_, pos))
	    {
	      conf->delta_y_ += dir *
		details_.tip_staff_line_clearance_ * 0.5 *  details_.staff_space_;
	    }
	}
      else 
	{
	  Real top_y = y + conf->delta_y_ + conf->dir_ * h;
	  Real top_pos = top_y / (0.5*details_.staff_space_);
	  int round_pos = int (my_round (top_pos));

	  /* TODO: should use other variable? */
	  Real clearance = details_.center_staff_line_clearance_;
	  if (fabs (top_pos - round_pos) < clearance
	      && Staff_symbol_referencer::on_staff_line (details_.staff_symbol_referencer_,
							 round_pos))
	    {
	      Real new_y = (round_pos + clearance * conf->dir_) * 0.5 * details_.staff_space_;
	      conf->delta_y_ = (new_y - top_y);
	    }
	}
    }
  
  conf->attachment_x_ = get_attachment (y + conf->delta_y_, conf->column_ranks_);
  if (conf->height (details_) < details_.intra_space_threshold_ * 0.5 * details_.staff_space_)
    {
      /*
	This is less sensible for long ties, since those are more
	horizontal.
      */
      Interval close_by = get_attachment (y
					  + conf->delta_y_
					  + (dir * details_.intra_space_threshold_ * 0.25
					     * details_.staff_space_),
					  conf->column_ranks_);
      
      conf->attachment_x_.intersect (close_by);
    }

  conf->attachment_x_.widen ( - details_.x_gap_);

  if (conf->column_span_length ())
    {
      /*
	avoid the stems that we attach to as well. We don't do this
	for semities (span length = 0)

	It would be better to check D against HEAD-DIRECTION if
	applicable.
      */
      Direction d = LEFT;
      do
	{
	  Real y = conf->position_ * details_.staff_space_ * 0.5 + conf->delta_y_;
	  if (get_stem_extent (conf->column_ranks_[d], d, X_AXIS).is_empty ()
	      || !get_stem_extent (conf->column_ranks_[d], d, Y_AXIS).contains (y))
	    continue;

	  conf->attachment_x_[d] =
	    d * min (d * conf->attachment_x_[d],
		     d * (get_stem_extent (conf->column_ranks_[d], d, X_AXIS)[-d] - d * details_.stem_gap_));
	}
      while (flip (&d) != LEFT);
    }  
  return conf;
}

Interval
Tie_formatting_problem::get_head_extent (int col, Direction d, Axis a) const
{
  Column_extent_map::const_iterator i = head_extents_.find (Tuple2<int> (col, int (d)));
  if (i != head_extents_.end ())
    return (*i).second[a];
  else
    return Interval ();
}

Interval
Tie_formatting_problem::get_stem_extent (int col, Direction d, Axis a) const
{
  Column_extent_map::const_iterator i = stem_extents_.find (Tuple2<int> (col, int (d)));
  if (i != stem_extents_.end ())
    return (*i).second[a];
  else
    return Interval ();
}

/**
   TIE_IDX and TIES_CONF are optional.
 */
Real
Tie_formatting_problem::score_aptitude (Tie_configuration *conf,
					Tie_specification const &spec,
					Ties_configuration *ties_conf, int tie_idx) const
{
  Real penalty = 0.0;
  Real curve_y = conf->position_ * details_.staff_space_ * 0.5 + conf->delta_y_;
  Real tie_y = spec.position_ * details_.staff_space_ * 0.5;
  if (sign (curve_y - tie_y) != conf->dir_)
    {
      Real p =  details_.wrong_direction_offset_penalty_;
      if (ties_conf)
	ties_conf->add_tie_score (p, tie_idx, "wrong dir");
      else
	penalty += p;
    }

  {
    Real p = details_.vertical_distance_penalty_factor_ * fabs (curve_y - tie_y);
    if (ties_conf)
      ties_conf->add_tie_score (p, tie_idx, "vdist");
    else
      penalty += p; 
  }
  
  Direction d = LEFT;
  do
    {
      if (!spec.note_head_drul_[d])
	continue;
      
      Interval head_x = spec.note_head_drul_[d]->extent (x_refpoint_, X_AXIS);
      Real dist = head_x.distance (conf->attachment_x_[d]);

      /*
	TODO: flatten with log or sqrt.
       */
      Real p = details_.horizontal_distance_penalty_factor_ * dist;
      if (ties_conf)
	ties_conf->add_tie_score (p, tie_idx,
				  (d == LEFT) ? "lhdist" : "rhdist");
      else
	penalty += p;
    }
  while (flip (&d) != LEFT);

  return penalty;
}

void
Tie_formatting_problem::score_configuration (Tie_configuration *conf) const
{
  if (conf->scored_)
    {
      return ;
    }
  
  Real length = conf->attachment_x_.length ();

  conf->add_score (details_.min_length_penalty_factor_
		   * peak_around (0.33 * details_.min_length_, details_.min_length_, length),
		   "minlength");
  
  Real tip_pos = conf->position_ + conf->delta_y_ / 0.5 * details_.staff_space_;
  Real tip_y = tip_pos * details_.staff_space_ * 0.5;
  Real height =  conf->height (details_);

  Real top_y = tip_y + conf->dir_ * height;
  Real top_pos = 2 * top_y / details_.staff_space_;
  Real round_top_pos = rint (top_pos);
  if (Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_,
						int (round_top_pos))
      && Staff_symbol_referencer::staff_radius (details_.staff_symbol_referencer_) > top_y)
    {
      conf->add_score (
	details_.staff_line_collision_penalty_
	* peak_around (0.1 * details_.center_staff_line_clearance_,
		     details_.center_staff_line_clearance_,
		       fabs (top_pos - round_top_pos)),
	"line center");
    }
  
  if (Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_,
					int (rint (tip_pos))))
    {
      conf->add_score (details_.staff_line_collision_penalty_
		       * peak_around (0.1 * details_.tip_staff_line_clearance_,
				      details_.tip_staff_line_clearance_,
				      fabs (tip_pos - rint (tip_pos))),
		       "tipline");
    }

  if (!dot_x_.is_empty ())
    {
      /* use left edge? */
      Real x = dot_x_.center ();
      
      Bezier b = conf->get_transformed_bezier (details_);
      if (b.control_point_extent (X_AXIS).contains (x))
	{
	  Real y = b.get_other_coordinate (X_AXIS, x);

	  for (set<int>::const_iterator i (dot_positions_.begin ());
	       i != dot_positions_.end (); i ++)
	    {
	      int dot_pos = (*i);
	      conf->add_score (details_.dot_collision_penalty_
		* peak_around (.1 * details_.dot_collision_clearance_,
			       details_.dot_collision_clearance_,
			       fabs (dot_pos * details_.staff_space_ * 0.5 - y)),
			       "dot collision");
	    }
	}
    }

  conf->scored_ = true;
}

Tie_configuration
Tie_formatting_problem::find_optimal_tie_configuration (Tie_specification const &spec) const
{
  vector<Tie_configuration*> confs;

  int pos = spec.position_;
  Direction dir = spec.manual_dir_;

  for (int i = 0; i < details_.single_tie_region_size_; i ++)
    {
      confs.push_back (generate_configuration (pos + i * dir, dir,
					       spec.column_ranks_));
      
      if (spec.has_manual_position_)
	{
	  confs.back ()->delta_y_
	    = (spec.manual_position_ - spec.position_)
	    * 0.5 * details_.staff_space_;

	  break;
	}
    }

  vector<Real> scores;

  int best_idx = -1;
  Real best_score = 1e6;
  for (vsize i = 0; i < confs.size (); i ++)
    {
      score_configuration (confs[i]);
      Real score = score_aptitude (confs[i], spec, 0, 0)
	+ confs[i]->score ();

      if (score < best_score)
	{
	  best_score = score;
	  best_idx = i;
	}
    }

  if (best_idx < 0)
    programming_error ("No best tie configuration found.");

  Tie_configuration best
    = (best_idx >= 0) ?  *confs[best_idx] : *confs[0];
  
  for (vsize i = 0; i < confs.size (); i++)
    delete confs[i];

  return best;
}

Tie_specification::Tie_specification ()
{
  has_manual_position_ = false;
  has_manual_dir_ = false;
  position_ = 0;
  manual_position_ = 0;
  manual_dir_ = CENTER;
  note_head_drul_[LEFT] =
    note_head_drul_[RIGHT] = 0;
  column_ranks_[RIGHT] =
    column_ranks_[LEFT] = 0;
}


void
Tie_specification::get_tie_manual_settings (Grob *tie)
{
  if (scm_is_number (tie->get_property_data ("direction")))
    {
      manual_dir_ = to_dir (tie->get_property ("direction"));
      has_manual_dir_ = true;
    }
  
  position_ = Tie::get_position (tie);
  if (scm_is_number (tie->get_property ("staff-position")))
    {
      manual_position_ = scm_to_double (tie->get_property ("staff-position"));
      has_manual_position_ = true;
      position_ = int (my_round (manual_position_));
    }
}

int
Tie_specification::column_span () const
{
  return column_ranks_[RIGHT] - column_ranks_[LEFT];
}

void
Tie_formatting_problem::score_ties_aptitude (Ties_configuration *ties) const
{
  if  (ties->size () != specifications_.size ())
    {
      programming_error ("Huh? Mismatch between sizes.");
      return;
    }

  for (vsize i = 0; i < ties->size (); i++)
    score_aptitude (&ties->at (i), specifications_[i],
		    ties, i);
}

void
Tie_formatting_problem::score_ties (Ties_configuration *ties) const
{
  if (ties->scored_)
    return;
  
  score_ties_configuration (ties);
  score_ties_aptitude (ties);
  ties->scored_ = true;
}

void
Tie_formatting_problem::score_ties_configuration (Ties_configuration *ties) const
{
  for (vsize i = 0; i < ties->size (); i++)
    {
      score_configuration (&ties->at (i));
      ties->add_tie_score (ties->at (i).score (), i, "conf");
    }
  
  Real last_edge = 0.0;
  Real last_center = 0.0;
  for (vsize i = 0; i < ties->size (); i++)
    {
      Bezier b (ties->at (i).get_transformed_bezier (details_));
	
      Real center = b.curve_point (0.5)[Y_AXIS];
      Real edge = b.curve_point (0.0)[Y_AXIS];
      
      if (i)
	{
	  if (edge <= last_edge)
	    ties->add_score (details_.tie_column_monotonicity_penalty_, "monoton edge");
	  if (center <= last_center)
	    ties->add_score (details_.tie_column_monotonicity_penalty_, "monoton cent");

	  ties->add_score (details_.tie_tie_collision_penalty_ *
			   peak_around (0.1 * details_.tie_tie_collision_distance_,
					details_.tie_tie_collision_distance_,
					fabs (center - last_center)),
			   "tietie center");
	  ties->add_score (details_.tie_tie_collision_penalty_ *
			   peak_around (0.1 * details_.tie_tie_collision_distance_,
					details_.tie_tie_collision_distance_,
					fabs (edge - last_edge)), "tietie edge");
	}

      last_edge = edge;
      last_center = center;
    }

  ties->add_score (details_.outer_tie_length_symmetry_penalty_factor_
		   * fabs (ties->at (0).attachment_x_.length () - ties->back ().attachment_x_.length ()),
		   "length symm");
  
  ties->add_score (details_.outer_tie_vertical_distance_symmetry_penalty_factor_
		   * fabs (fabs (specifications_[0].position_ * 0.5 * details_.staff_space_
				 - (ties->at (0).position_ * 0.5 * details_.staff_space_
				    + ties->at (0).delta_y_))
			   -
			   fabs (specifications_.back ().position_ * 0.5 * details_.staff_space_
				 - (ties->back ().position_ * 0.5 * details_.staff_space_
				    + ties->back ().delta_y_))),
		   "pos symmetry");
}

/*
  Generate with correct X-attachments and beziers, copying delta_y_
  from TIES_CONFIG if necessary.
*/
Ties_configuration
Tie_formatting_problem::generate_ties_configuration (Ties_configuration const &ties_config)
{
  Ties_configuration copy;
  for (vsize i = 0; i < ties_config.size (); i++)
    {
      Tie_configuration * ptr = get_configuration (ties_config[i].position_, ties_config[i].dir_,
						   ties_config[i].column_ranks_);
      if (specifications_[i].has_manual_position_)
	{
	  ptr->delta_y_
	    = (specifications_[i].manual_position_ - ties_config[i].position_)
	    * 0.5 * details_.staff_space_;
	}
      copy.push_back (*ptr);
    }
  
  return copy;
}

Ties_configuration
Tie_formatting_problem::generate_base_chord_configuration () 
{
  Ties_configuration ties_config;
  for (vsize i = 0;  i < specifications_.size (); i ++)
    {
      Tie_configuration conf;
      if (specifications_[i].has_manual_dir_)
	conf.dir_ = specifications_[i].manual_dir_;
      if (specifications_[i].has_manual_position_)
	{
	  conf.position_ = (int) my_round (specifications_[i].manual_position_);
	  conf.delta_y_ = (specifications_[i].manual_position_ - conf.position_)
	    * 0.5 * details_.staff_space_;
	}
      else
	{
	  conf.position_ = specifications_[i].position_;
	}

      conf.column_ranks_ = specifications_[i].column_ranks_;
      ties_config.push_back (conf);
    }

  set_ties_config_standard_directions (&ties_config);
  for (vsize i = 0; i < ties_config.size (); i++)
    if (!specifications_[i].manual_position_)
      ties_config[i].position_ += ties_config[i].dir_;

  ties_config = generate_ties_configuration (ties_config);
  
  return ties_config;
}

Ties_configuration
Tie_formatting_problem::find_best_variation (Ties_configuration const &base,
					     vector<Tie_configuration_variation> vars)
{
  Ties_configuration best = base;
  
  /*
    This simply is 1-opt: we have K substitions, and we try applying
    exactly every one for each.
  */
  for (vsize i = 0; i < vars.size (); i++)
    {
      Ties_configuration variant (base);
      variant[vars[i].index_] = *vars[i].suggestion_;

      variant.reset_score ();
      score_ties (&variant);
      
      if (variant.score () < best.score ())
	{
	  best = variant;
	}
    }

  return best;
}
  
				       

Ties_configuration
Tie_formatting_problem::generate_optimal_chord_configuration ()
{
  Ties_configuration base = generate_base_chord_configuration ();
  vector<Tie_configuration_variation> vars = generate_collision_variations (base);
  
  score_ties (&base);
  Ties_configuration best = find_best_variation (base, vars);
  vars = generate_extremal_tie_variations (best);
  best = find_best_variation (best, vars);

  return best;
}

void
Tie_formatting_problem::set_ties_config_standard_directions (Ties_configuration *tie_configs)
{
  if (tie_configs->empty ())
    return ;

  if (!tie_configs->at (0).dir_)
    {
      if (tie_configs->size () == 1)
	tie_configs->at (0).dir_ = Direction (sign (tie_configs->at (0).position_));

      if (!tie_configs->at (0).dir_)
	tie_configs->at (0).dir_ = DOWN;
    }
  
  if (!tie_configs->back ().dir_)
    tie_configs->back ().dir_ = UP;

  /*
    Seconds
   */
  for (vsize i = 1; i < tie_configs->size (); i++)
    {
      Real diff = (tie_configs->at (i).position_
		   -tie_configs->at (i-1).position_);
		   
      Real span_diff 
	= specifications_[i].column_span () - specifications_[i-1].column_span ();
      if (span_diff && fabs (diff) <= 2)
	{
	  if  (span_diff > 0)
	    tie_configs->at (i).dir_ = UP;
	  else if (span_diff < 0)
	    tie_configs->at (i-1).dir_ = DOWN;  
	}
      else if (fabs (diff) <= 1)
	{
	  if (!tie_configs->at (i-1).dir_)
	    tie_configs->at (i-1).dir_ = DOWN;
	  if (!tie_configs->at (i).dir_)
	    tie_configs->at (i).dir_ = UP;
	}
    }

  for (vsize i = 1; i + 1 < tie_configs->size (); i++)
    {
      Tie_configuration &conf = tie_configs->at (i);
      if (conf.dir_)
	continue;

      Direction position_dir =
	Direction (sign (conf.position_));
      if (!position_dir)
	position_dir = DOWN;

      conf.dir_ = position_dir;
    }
}

Tie_configuration_variation::Tie_configuration_variation ()
{
  index_ = 0;
  suggestion_ = 0;
}

vector<Tie_configuration_variation>
Tie_formatting_problem::generate_extremal_tie_variations (Ties_configuration const &ties) const
{
  vector<Tie_configuration_variation> vars;
  Direction d = DOWN;
  do
    {
      if (boundary (ties, d, 0).dir_ == d
	  && !boundary (specifications_, d, 0).has_manual_position_)
	for (int i = 1; i <= details_.multi_tie_region_size_; i++)
	  {
	    Tie_configuration_variation var;
	    var.index_ = (d == DOWN) ? 0 : ties.size () - 1;
	    var.suggestion_ = get_configuration (boundary (ties, d, 0).position_
						 + d * i, d,
						 boundary (ties, d, 0).column_ranks_);
	    vars.push_back (var);
	  }
    }
  while (flip (&d) !=  DOWN);

  return vars;
}


vector<Tie_configuration_variation>
Tie_formatting_problem::generate_collision_variations (Ties_configuration const &ties) const
{
  Real center_distance_tolerance = 0.25;
  
  vector<Tie_configuration_variation> vars;
  Real last_center = 0.0;
  for (vsize i = 0; i < ties.size (); i++)
    {
      Bezier b (ties[i].get_transformed_bezier (details_));
	
      Real center = b.curve_point (0.5)[Y_AXIS];
      
      if (i)
	{
	  if (center <= last_center + center_distance_tolerance)
	    {
	      if (!specifications_[i].has_manual_dir_)
		{
		  Tie_configuration_variation var;
		  var.index_ = i;
		  var.suggestion_ = get_configuration (specifications_[i].position_
						       - ties[i].dir_,
						       - ties[i].dir_,

						       ties[i].column_ranks_
						       );

		  vars.push_back (var);
		}

	      if (!specifications_[i-1].has_manual_dir_)
		{
		  Tie_configuration_variation var;
		  var.index_ = i-1;
		  var.suggestion_ = get_configuration (specifications_[i-1].position_
						       - ties[i-1].dir_,
						       - ties[i-1].dir_,
						       specifications_[i-1].column_ranks_);

		  vars.push_back (var);
		}

	      if (i == 1 && !specifications_[i-1].has_manual_position_
		  && ties[i-1].dir_ == DOWN)
		{
		  Tie_configuration_variation var;
		  var.index_ = i-1;
		  var.suggestion_ = get_configuration (specifications_[i-1].position_ - 1, DOWN,
						       specifications_[i-1].column_ranks_);
		  vars.push_back (var);
		}
	      if (i == ties.size() && !specifications_[i].has_manual_position_
		  && ties[i].dir_ == UP)
		{
		  Tie_configuration_variation var;
		  var.index_ = i;
		  var.suggestion_ = get_configuration (specifications_[i].position_
						       + 1, UP,
						       specifications_[i].column_ranks_);
		  vars.push_back (var);
		}
	    }
	  else if (dot_positions_.find (ties[i].position_) != dot_positions_.end ()
		   && !specifications_[i].has_manual_position_)
	    {
	      Tie_configuration_variation var;
	      var.index_ = i;
	      var.suggestion_ = get_configuration (ties[i].position_  + ties[i].dir_,
						   ties[i].dir_,
						   ties[i].column_ranks_);
	      vars.push_back (var);
	    }
	  
	}

      last_center = center;
    }


  return vars;
}

void
Tie_formatting_problem::set_manual_tie_configuration (SCM manual_configs)
{
  vsize k = 0;
  for (SCM s = manual_configs;
       scm_is_pair (s) && k < specifications_.size (); s = scm_cdr (s))
    {
      SCM entry = scm_car (s);
      if (scm_is_pair (entry))
	{
	  Tie_specification &spec = specifications_[k];

	  if (scm_is_number (scm_car (entry)))
	    {
	      spec.has_manual_position_ = true;
	      spec.manual_position_ = scm_to_double (scm_car (entry));
	    }
	  if (scm_is_number (scm_cdr (entry)))
	    {
	      spec.has_manual_dir_ = true;
	      spec.manual_dir_ = Direction (scm_to_int (scm_cdr (entry)));
	    }
	}	  
      k ++;
    }
}

