/*
  This file is part of LilyPond, the GNU music typesetter.

  Copyright (C) 1996--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>

  LilyPond is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  LilyPond is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "time-signature.hh"

#include "grob.hh"
#include "font-interface.hh"
#include "international.hh"
#include "output-def.hh"
#include "staff-symbol-referencer.hh"
#include "text-interface.hh"
#include "warn.hh"

/*
  TODO:

  this file should go ; The formatting can completely be done with
  markups.
*/

MAKE_SCHEME_CALLBACK (Time_signature, print, 1);
SCM
Time_signature::print (SCM smob)
{
  Grob *me = unsmob_grob (smob);
  SCM st = me->get_property ("style");
  SCM frac = me->get_property ("fraction");
  int n = 4;
  int d = 4;
  if (scm_is_pair (frac))
    {
      n = scm_to_int (scm_car (frac));
      d = scm_to_int (scm_cdr (frac));
    }

  Stencil m;
  if (st == ly_symbol2scm ("single-digit"))
    m = numbered_time_signature (me, n, 0);
  else if (scm_is_symbol (st))
    m = special_time_signature (me, st, n, d);
  else
    m = numbered_time_signature (me, n, d);

  if (Staff_symbol_referencer::line_count (me) % 2 == 0)
    m.translate_axis (Staff_symbol_referencer::staff_space (me) / 2, Y_AXIS);

  return m.smobbed_copy ();
}

Stencil
Time_signature::special_time_signature (Grob *me, SCM scm_style, int n, int d)
{
  string style = ly_scm2string (scm_symbol_to_string (scm_style));

  if (style == "numbered")
    return numbered_time_signature (me, n, d);

  if ((style == "default") || (style == ""))
    style = to_string ("C");

  if (style == "C")
    {
      if /* neither C2/2 nor C4/4 */
	(((n != 2) || (d != 2))
	 && ((n != 4) || (d != 4)))
	return numbered_time_signature (me, n, d);
    }

  string char_name = style + to_string (n) + to_string (d);
  me->set_property ("font-encoding", ly_symbol2scm ("fetaMusic"));
  Stencil out = Font_interface::get_default_font (me)
    ->find_by_name ("timesig." + char_name);
  if (!out.is_empty ())
    return out;

  /* If there is no such symbol, we default to the numbered style.
     (Here really with a warning!) */
  me->warning (_f ("time signature symbol `%s' not found; "
		   "reverting to numbered style", char_name));
  return numbered_time_signature (me, n, d);
}

Stencil
Time_signature::numbered_time_signature (Grob *me, int num, int den)
{
  SCM chain = me->get_property_alist_chain (Font_interface::text_font_alist_chain (me));
  chain = scm_cons (scm_list_1 (scm_cons (ly_symbol2scm ("font-encoding"),
					  ly_symbol2scm ("fetaText"))),
		    chain);

  SCM sn = Text_interface::interpret_markup (me->layout ()->self_scm (), chain,
					     ly_string2scm (to_string (num)));
  SCM sd = Text_interface::interpret_markup (me->layout ()->self_scm (), chain,
					     ly_string2scm (to_string (den)));

  Stencil n = *unsmob_stencil (sn);
  Stencil d = *unsmob_stencil (sd);

  n.align_to (X_AXIS, CENTER);
  d.align_to (X_AXIS, CENTER);
  Stencil m;
  if (den)
    {
      m.add_at_edge (Y_AXIS, UP, n, 0.0);
      m.add_at_edge (Y_AXIS, DOWN, d, 0.0);
    }
  else
    {
      m = n;
      m.align_to (Y_AXIS, CENTER);
    }

  m.align_to (X_AXIS, LEFT);

  return m;
}

ADD_INTERFACE (Time_signature,
	       "A time signature, in different styles.  The following values"
	       " for @code{style} are are recognized:\n"
	       "\n"
	       "@table @code\n"
	       "@item C\n"
	       "4/4 and 2/2 are typeset as C and struck C, respectively."
	       "  All other time signatures are written with two digits."
	       "  The value @code{default} is equivalent to @code{C}.\n"
	       "@item neomensural\n"
	       "2/2, 3/2, 2/4, 3/4, 4/4, 6/4, 9/4, 4/8, 6/8, and 9/8 are"
	       " typeset with neo-mensural style mensuration marks.  All"
	       " other time signatures are written with two digits.\n"
	       "@item mensural\n"
	       "2/2, 3/2, 2/4, 3/4, 4/4, 6/4, 9/4, 4/8, 6/8, and 9/8 are"
	       " typeset with mensural style mensuration marks.  All other"
	       " time signatures are written with two digits.\n"
	       "@item single-digit\n"
	       "All time signatures are typeset with a single digit, e.g.,"
	       " 3/2 is written as 3.\n"
	       "@item numbered\n"
	       "All time signatures are typeset with two digits.\n"
	       "@end table",

	       /* properties */
	       "fraction "
	       "style "
	       );