/*
  cluster.cc -- implement Cluster

  source file of the GNU LilyPond music typesetter

  (c) 2002--2004 Juergen Reuter <reuter@ipd.uka.de>

  Han-Wen Nienhuys <hanwen@cs.uu.nl>

*/

#include <stdio.h>

#include "cluster.hh"
#include "spanner.hh"
#include "item.hh"
#include "pitch.hh"
#include "staff-symbol-referencer.hh"
#include "lookup.hh"
#include "box.hh"
#include "interval.hh"
#include "output-def.hh"
#include "warn.hh"


/*
   TODO: Add support for cubic spline segments.

 */
Stencil
brew_cluster_piece (Grob *me, Array<Offset> bottom_points, Array<Offset> top_points)
{
  Real blotdiameter = Staff_symbol_referencer::staff_space (me)/2;

  Real padding =robust_scm2double ( me->get_property ("padding"), 0.0);

  Offset vpadding = Offset (0, padding);
  Offset hpadding = Offset (0.5 * blotdiameter, 0);
  Offset hvpadding = 0.5 * hpadding + vpadding;

  SCM shape_scm = me->get_property ("style");
  String shape;

  if (scm_is_symbol (shape_scm))
    {
      shape = ly_symbol2string (shape_scm);
    }
  else
    {
      programming_error ("#'style should be symbol.");
      me->suicide ();
      return  Stencil ();
    }


  Stencil out;
  Array<Offset> points;
  points.clear ();
  int size = bottom_points.size ();
  if (String::compare (shape, "leftsided-stairs") == 0)
    {
      for (int i = 0; i < size - 1; i++)
	{
	  Box box;
	  box.add_point (bottom_points[i] - hvpadding);
	  box.add_point (Offset (top_points[i + 1][X_AXIS],
				top_points[i][Y_AXIS]) + hvpadding);
	  out.add_stencil (Lookup::round_filled_box (box, blotdiameter));
	}
    }
  else if (String::compare (shape, "rightsided-stairs") == 0)
    {
      for (int i = 0; i < size - 1; i++)
	{
	  Box box;
	  box.add_point (Offset (bottom_points[i][X_AXIS],
				bottom_points[i + 1][Y_AXIS]) - hvpadding);
	  box.add_point (top_points[i + 1] + hvpadding);
	  out.add_stencil (Lookup::round_filled_box (box, blotdiameter));
	}
    }
  else if (String::compare (shape, "centered-stairs") == 0)
    {
      Real left_xmid = bottom_points[0][X_AXIS];
      for (int i = 0; i < size - 1; i++)
	{
	  Real right_xmid =
	    0.5 * (bottom_points[i][X_AXIS] + bottom_points[i + 1][X_AXIS]);
	  Box box;
	  box.add_point (Offset (left_xmid, bottom_points[i][Y_AXIS]) -
			 hvpadding);
	  box.add_point (Offset (right_xmid, top_points[i][Y_AXIS]) +
			 hvpadding);
	  out.add_stencil (Lookup::round_filled_box (box, blotdiameter));
	  left_xmid = right_xmid;
	}
      Real right_xmid = bottom_points[size - 1][X_AXIS];
      Box box;
      box.add_point (Offset (left_xmid, bottom_points[size - 1][Y_AXIS]) -
		     hvpadding);
      box.add_point (Offset (right_xmid, top_points[size - 1][Y_AXIS]) +
		     hvpadding);
      out.add_stencil (Lookup::round_filled_box (box, blotdiameter));
    }
  else if (String::compare (shape, "ramp") == 0)
    {
      points.push (bottom_points[0] - vpadding + hpadding);
      for (int i = 1; i < size - 1; i++)
	{
	  points.push (bottom_points[i] - vpadding);
	}
      points.push (bottom_points[size - 1] - vpadding - hpadding);
      points.push (top_points[size - 1] + vpadding - hpadding);
      for (int i = size - 2; i > 0; i--)
	{
	  points.push (top_points[i] + vpadding);
	}
      points.push (top_points[0] + vpadding + hpadding);
      out.add_stencil (Lookup::round_filled_polygon (points, blotdiameter));
    }
  else
    {
      me->warning (_f ("unknown cluster style `%s'", shape.to_str0 ()));
    }
  return out;
}

MAKE_SCHEME_CALLBACK (Cluster,print,1);
SCM
Cluster::print (SCM smob)
{
  Grob *me = unsmob_grob (smob);

  Spanner *spanner = dynamic_cast<Spanner*> (me);
  if (!spanner)
    {
      me->programming_error ("Cluster::print (): not a spanner");
      return SCM_EOL;
    }

  Item *left_bound = spanner->get_bound (LEFT);
  Item *right_bound = spanner->get_bound (RIGHT);

  Grob *commonx = left_bound->common_refpoint (right_bound, X_AXIS);
  SCM cols  =me->get_property ("columns");

  if (!scm_is_pair (cols))
    {
      me->warning ("junking empty cluster");
      me->suicide ();
      
      return SCM_EOL;
    }
  
  commonx = common_refpoint_of_list (cols, commonx, X_AXIS);
  Grob * commony = common_refpoint_of_list (cols, me, Y_AXIS);
  Array<Offset> bottom_points;
  Array<Offset> top_points;


  Real left_coord = left_bound->relative_coordinate (commonx, X_AXIS);

  /*
    TODO: should we move the cluster a little to the right to be in
    line with the center of the note heads?
    
   */
  for (SCM s = cols; scm_is_pair (s); s = scm_cdr (s))
    {
      Grob * col = unsmob_grob (scm_car (s));
      Interval yext = col->extent (commony, Y_AXIS);

      Real x = col->relative_coordinate (commonx, X_AXIS) - left_coord;
      bottom_points.push (Offset (x, yext[DOWN]));
      top_points.push (Offset (x, yext[UP]));
    }

  /*
    Across a line break we anticipate on the next pitches.
   */
  if (spanner->original_)
    {
      Spanner *orig = dynamic_cast<Spanner*> (spanner->original_);
      
      if (spanner->get_break_index () < orig->broken_intos_.size ()-1)
	{
	  Spanner * next = orig->broken_intos_[spanner->get_break_index () + 1];
	  SCM cols = next->get_property ("columns");
	  if (scm_is_pair (cols))
	    {
	      Grob *next_commony = common_refpoint_of_list (cols, next, Y_AXIS);
	      Grob * col = unsmob_grob (scm_car (scm_last_pair (cols)));

	      Interval v = col->extent (next_commony, Y_AXIS);
	      Real x = right_bound->relative_coordinate (commonx, X_AXIS) - left_coord;
	      
	      bottom_points.insert (Offset (x, v[DOWN]),0);
	      top_points.insert (Offset (x, v[UP]),0);
	    }
	}
    }

  bottom_points.reverse ();
  top_points.reverse ();

  Stencil out = brew_cluster_piece (me, bottom_points, top_points);
  out.translate_axis (- me->relative_coordinate (commony, Y_AXIS), Y_AXIS);
  return out.smobbed_copy ();
}

ADD_INTERFACE (Cluster,"cluster-interface",
	       "A graphically drawn musical cluster. " 
	       "\n\n"
	       "@code{padding} adds to the vertical extent of the shape (top and "
	       "bottom). \n\n"
	       "The property @code{style} controls the shape of cluster segments.  Valid values "
	       "include @code{leftsided-stairs}, @code{rightsided-stairs}, @code{centered-stairs}, "
	       "and @code{ramp}.\n"
,
  "style padding columns");



struct Cluster_beacon
{
public:
  DECLARE_SCHEME_CALLBACK (height, (SCM, SCM));
  static bool has_interface (Grob *);
};

MAKE_SCHEME_CALLBACK (Cluster_beacon,height,2);
SCM
Cluster_beacon::height (SCM g, SCM)
{
  Grob *me = unsmob_grob (g);
  Interval v = robust_scm2interval (me->get_property ("positions"),
				    Interval (0,0));
  return ly_interval2scm (Staff_symbol_referencer::staff_space (me) * 0.5 * v);
}



ADD_INTERFACE(Cluster_beacon,
	      "cluster-beacon-interface",
	      "A place holder for the cluster spanner to determine the vertical "
	      "extents of a cluster spanner at this X position.",
	      "positions");
