/*
  molecule.cc -- implement Molecule

  source file of the GNU LilyPond music typesetter

  (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
*/

#include <math.h>
#include <libc-extension.hh>	// isinf

#include "font-metric.hh" 
#include "dimensions.hh"
#include "interval.hh"
#include "string.hh"
#include "molecule.hh"
#include "debug.hh"


#include "ly-smobs.icc"


SCM
Molecule::smobbed_copy () const
{
  Molecule * m = new Molecule (*this);

  return m->smobbed_self ();
}

Interval
Molecule::extent (Axis a) const
{
  return dim_[a];
}

Molecule::Molecule (Box b, SCM func)
{
  expr_ = func;
  dim_ = b;
}

Molecule::Molecule ()
{
  expr_ = SCM_EOL;
  set_empty (true);
}

void
Molecule::translate (Offset o)
{
  Axis a = X_AXIS;
  while (a < NO_AXES)
    {
      if (abs (o[a]) > 30 CM
	  || isinf (o[a]) || isnan (o[a]))
	{
	  programming_error ("Improbable offset for translation: setting to zero");
	  o[a] =  0.0;
	}
      incr (a);
    }

  expr_ = gh_list (ly_symbol2scm ("translate-molecule"),
		   ly_offset2scm (o),
		   expr_, SCM_UNDEFINED);
  if (!empty_b ())
    dim_.translate (o);
}
  

void
Molecule::translate_axis (Real x,Axis a)
{
  Offset o (0,0);
  o[a] = x;
  translate (o);
}  



void
Molecule::add_molecule (Molecule const &m)
{
  expr_ = gh_list (ly_symbol2scm ("combine-molecule"),
		   m.expr_,
		   expr_, SCM_UNDEFINED);
  dim_.unite (m.dim_);
}

void
Molecule::set_empty (bool e)
{
  if (e)
    {
      dim_[X_AXIS].set_empty ();
      dim_[Y_AXIS].set_empty ();
    }
  else
    {
      dim_[X_AXIS] = Interval (0,0);
      dim_[Y_AXIS] = Interval (0,0);
    }
}


void
Molecule::align_to (Axis a, Direction d)
{
  Interval i (extent (a));
  Real r = (d == CENTER) ? i.center () : i[d];
  translate_axis (-r, a);
}

void
Molecule::add_at_edge (Axis a, Direction d, Molecule const &m, Real padding)
{
  Real my_extent= empty_b () ? 0.0 : dim_[a][d];
  Interval i (m.extent (a));
  Real his_extent;
  if (i.empty_b ())
    {
      programming_error ("Molecule::add_at_edge: adding empty molecule.");
      his_extent = 0.0;
    }
  else
    his_extent = i[-d];      

  Real offset = my_extent -  his_extent;
  Molecule toadd (m);
  toadd.translate_axis (offset + d * padding, a);
  add_molecule (toadd);
}

/* ly_?  Thought we had the ly_ prefix for wrapping/adding to gh_ */
SCM
Molecule::ly_set_molecule_extent_x (SCM mol, SCM axis, SCM np)
{
  Molecule* m = unsmob_molecule (mol);
  if (m && ly_axis_p (axis) && ly_number_pair_p (np))
    {
      Interval iv = ly_scm2interval (np);
      m->dim_[Axis (gh_scm2int (axis))] = ly_scm2interval (np);
    }
  else
    warning ("ly-set-molecule-extent!: invalid arguments");
  return SCM_UNDEFINED;
}

SCM
Molecule::ly_get_molecule_extent (SCM mol, SCM axis)
{
  Molecule *m = unsmob_molecule (mol);
 
  if (!m || !ly_axis_p (axis))
    {
      warning ("ly-get-molecule-extent: invalid arguments");
      return ly_interval2scm (Interval (0,0));
    }

  return ly_interval2scm (m->extent (Axis (gh_scm2int (axis))));
}


SCM
Molecule::ly_molecule_combined_at_edge (SCM first, SCM axis, SCM direction,
			   SCM second, SCM padding)

{
  Molecule * m1 = unsmob_molecule (first);
  Molecule * m2 = unsmob_molecule (second);
  Molecule result;
  
  if (!m1 || !m2 || !isdir_b (direction) || !ly_axis_p (axis) || !gh_number_p (padding))
    {
      warning ("ly-combine-molecule-at-edge: invalid arguments");
      Molecule r;
      return  r.smobbed_copy ();
    }

  result = *m1;

  result.add_at_edge (Axis (gh_scm2int (axis)), Direction (gh_scm2int (direction)),
		      *m2, gh_scm2double (padding));

  return result.smobbed_copy ();
}


SCM
make_molecule (SCM expr, SCM xext, SCM yext)
{
  /*
    TODO: typechecking. 
   */
  Box b (ly_scm2interval (xext), ly_scm2interval(yext));
  Molecule m (b, expr);
  return m.smobbed_copy ();
}


static void
molecule_init ()
{
  scm_c_define_gsubr ("ly-make-molecule", 3, 0, 0, (Scheme_function_unknown) make_molecule);
  scm_c_define_gsubr ("ly-combine-molecule-at-edge", 5 , 0, 0, (Scheme_function_unknown) Molecule::ly_molecule_combined_at_edge);
  scm_c_define_gsubr ("ly-set-molecule-extent!", 3 , 0, 0, (Scheme_function_unknown) Molecule::ly_set_molecule_extent_x);
  scm_c_define_gsubr ("ly-get-molecule-extent", 2 , 0, 0, (Scheme_function_unknown) Molecule::ly_get_molecule_extent);
}
ADD_SCM_INIT_FUNC (molecule,molecule_init);


bool
Molecule::empty_b () const
{
  return expr_ == SCM_EOL;
}

SCM
fontify_atom (Font_metric * met, SCM f)
{
  if (f == SCM_EOL)
    return f;
  else
    return  gh_list (ly_symbol2scm ("fontify"),
		     ly_quote_scm (met->description_), f, SCM_UNDEFINED);
}

SCM
Molecule::get_expr () const
{
  return expr_;
}



Box
Molecule::extent_box () const
{
  return dim_;
}
IMPLEMENT_SIMPLE_SMOBS (Molecule);


int
Molecule::print_smob (SCM s, SCM port, scm_print_state *)
{
  Molecule  *r = (Molecule *) gh_cdr (s);
     
  scm_puts ("#<Molecule ", port);
  /*  String str (r->str ());
  scm_puts ((char *)str.ch_C (), port);*/
  scm_puts (" >", port);
  
  return 1;
}

  
SCM
Molecule::mark_smob (SCM s)
{
  Molecule  *r = (Molecule *) gh_cdr (s);
  
  return r->expr_;
}

IMPLEMENT_TYPE_P (Molecule, "molecule?");
IMPLEMENT_DEFAULT_EQUAL_P (Molecule);
IMPLEMENT_UNSMOB (Molecule, molecule);
