/* Dia -- an diagram creation/manipulation program
 * Copyright (C) 1998 Alexander Larsson
 *
 * GRAFCET chart support 
 * Copyright (C) 2000,2001 Cyrille Chepelov
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <assert.h>
#include <math.h>

#include "intl.h"
#include "object.h"
#include "connection.h"
#include "connectionpoint.h"
#include "diarenderer.h"
#include "attributes.h"
#include "widgets.h"
#include "message.h"
#include "color.h"
#include "properties.h"
#include "geometry.h"
#include "text.h"

#include "grafcet.h"
#include "boolequation.h"

#include "pixmaps/condition.xpm"

#define CONDITION_LINE_WIDTH GRAFCET_GENERAL_LINE_WIDTH
#define CONDITION_FONT BASIC_SANS_FONT
#define CONDITION_FONT_STYLE STYLE_BOLD
#define CONDITION_FONT_HEIGHT 0.8
#define CONDITION_LENGTH (1.5)
#define CONDITION_ARROW_SIZE 0.0 /* XXX The norm says there's no arrow head.
                                    a lot of people do put it, though. */

typedef struct _Condition {
  Connection connection;
  
  Boolequation *cond;

  gchar *cond_value;
  DiaFont *cond_font;
  real cond_fontheight;
  Color cond_color;

  /* computed values : */
  Rectangle labelbb;
} Condition;

static ObjectChange* condition_move_handle(Condition *condition, Handle *handle,
					   Point *to, ConnectionPoint *cp,
					   HandleMoveReason reason, ModifierKeys modifiers);
static ObjectChange* condition_move(Condition *condition, Point *to);
static void condition_select(Condition *condition, Point *clicked_point,
			      DiaRenderer *interactive_renderer);
static void condition_draw(Condition *condition, DiaRenderer *renderer);
static DiaObject *condition_create(Point *startpoint,
				 void *user_data,
				 Handle **handle1,
				 Handle **handle2);
static real condition_distance_from(Condition *condition, Point *point);
static void condition_update_data(Condition *condition);
static void condition_destroy(Condition *condition);
static DiaObject *condition_load(ObjectNode obj_node, int version,
			       const char *filename);
static PropDescription *condition_describe_props(Condition *condition);
static void condition_get_props(Condition *condition, 
                                GPtrArray *props);
static void condition_set_props(Condition *condition, 
                                GPtrArray *props);

static ObjectTypeOps condition_type_ops =
{
  (CreateFunc)condition_create,   /* create */
  (LoadFunc)  condition_load /*using_properties*/,     /* load */
  (SaveFunc)  object_save_using_properties,      /* save */
  (GetDefaultsFunc)   NULL,
  (ApplyDefaultsFunc) NULL
};

DiaObjectType condition_type =
{
  "GRAFCET - Condition",   /* name */
  0,                         /* version */
  (char **) condition_xpm,      /* pixmap */
  
  &condition_type_ops       /* ops */
};


static ObjectOps condition_ops = {
  (DestroyFunc)         condition_destroy,
  (DrawFunc)            condition_draw,
  (DistanceFunc)        condition_distance_from,
  (SelectFunc)          condition_select,
  (CopyFunc)            object_copy_using_properties,
  (MoveFunc)            condition_move,
  (MoveHandleFunc)      condition_move_handle,
  (GetPropertiesFunc)   object_create_props_dialog,
  (ApplyPropertiesFunc) object_apply_props_from_dialog,
  (ObjectMenuFunc)      NULL,
  (DescribePropsFunc)   condition_describe_props,
  (GetPropsFunc)        condition_get_props,
  (SetPropsFunc)        condition_set_props
};


static PropDescription condition_props[] = {
  CONNECTION_COMMON_PROPERTIES,
  { "condition",PROP_TYPE_STRING, PROP_FLAG_VISIBLE|PROP_FLAG_DONT_MERGE,
    N_("Condition"),N_("The boolean equation of the condition")},
  { "cond_font",PROP_TYPE_FONT, PROP_FLAG_VISIBLE,
    N_("Font"),N_("The condition's font") },
  { "cond_fontheight",PROP_TYPE_REAL,PROP_FLAG_VISIBLE,
    N_("Font size"),N_("The condition's font size"),
    &prop_std_text_height_data},
  { "cond_color",PROP_TYPE_COLOUR,PROP_FLAG_VISIBLE,
    N_("Color"),N_("The condition's color")},
  PROP_DESC_END
};

static PropDescription *
condition_describe_props(Condition *condition) 
{
  if (condition_props[0].quark == 0) {
    prop_desc_list_calculate_quarks(condition_props);
  }
  return condition_props;
}

static PropOffset condition_offsets[] = {
  CONNECTION_COMMON_PROPERTIES_OFFSETS,
  {"condition",PROP_TYPE_STRING,offsetof(Condition,cond_value)},
  {"cond_font",PROP_TYPE_FONT,offsetof(Condition,cond_font)},
  {"cond_fontheight",PROP_TYPE_REAL,offsetof(Condition,cond_fontheight)},
  {"cond_color",PROP_TYPE_COLOUR,offsetof(Condition,cond_color)},
  { NULL,0,0 }
};

static void
condition_get_props(Condition *condition, GPtrArray *props)
{  
  object_get_props_from_offsets(&condition->connection.object,
                                condition_offsets,props);
}

static void
condition_set_props(Condition *condition, GPtrArray *props)
{
  object_set_props_from_offsets(&condition->connection.object,
                                condition_offsets,props);
  
  boolequation_set_value(condition->cond,condition->cond_value);
  dia_font_unref(condition->cond->font);
  condition->cond->font = dia_font_ref(condition->cond_font);
  condition->cond->fontheight = condition->cond_fontheight;
  condition->cond->color = condition->cond_color;
  condition_update_data(condition);
}

static real
condition_distance_from(Condition *condition, Point *point)
{
  Connection *conn = &condition->connection;
  real dist; 
  dist = distance_rectangle_point(&condition->labelbb,point);
  dist = MIN(dist,distance_line_point(&conn->endpoints[0],
				      &conn->endpoints[1],
				      CONDITION_LINE_WIDTH,point));
  return dist;
}

static void
condition_select(Condition *condition, Point *clicked_point,
		  DiaRenderer *interactive_renderer)
{
  condition_update_data(condition);
}

static ObjectChange*
condition_move_handle(Condition *condition, Handle *handle,
		       Point *to, ConnectionPoint *cp,
		      HandleMoveReason reason, ModifierKeys modifiers)
{
  Point s,e,v;
  int horiz;

  g_assert(condition!=NULL);
  g_assert(handle!=NULL);
  g_assert(to!=NULL);
  
  switch (handle->id) {
  case HANDLE_MOVE_STARTPOINT:
    point_copy(&s,to);
    point_copy(&e,&condition->connection.endpoints[1]);
    point_copy(&v,&e);
    point_sub(&v,&s);
    
    horiz = ABS(v.x) > ABS(v.y);
    if (horiz) {
      v.y = 0.0;
    } else {
      v.x = 0.0;
    }

    point_copy(&s,&e);
    point_sub(&s,&v);
    /* XXX: fix e to make it look good (what's good ?) V is a good hint ? */
    connection_move_handle(&condition->connection, HANDLE_MOVE_STARTPOINT,
			   &s, cp, reason, modifiers);    
    break;
  case HANDLE_MOVE_ENDPOINT:
    point_copy(&s,&condition->connection.endpoints[0]);
    point_copy(&e,&condition->connection.endpoints[1]);
    point_copy(&v,&e);
    point_sub(&v,&s);
    connection_move_handle(&condition->connection, HANDLE_MOVE_ENDPOINT,
			   to, cp, reason, modifiers);
    point_copy(&s,to);
    point_sub(&s,&v);
    connection_move_handle(&condition->connection, HANDLE_MOVE_STARTPOINT,
			   &s, NULL, reason, 0);    
    break;
  default:
    g_assert_not_reached();
  }
  condition_update_data(condition);

  return NULL;
}


static ObjectChange*
condition_move(Condition *condition, Point *to)
{
  Point start_to_end;
  Point *endpoints = &condition->connection.endpoints[0]; 

  start_to_end = endpoints[1];
  point_sub(&start_to_end, &endpoints[0]);
  point_copy(&endpoints[0],to);
  point_copy(&endpoints[1],to);
  point_add(&endpoints[1], &start_to_end);

  condition_update_data(condition);

  return NULL;
}

static void
condition_update_data(Condition *condition)
{
  Connection *conn = &condition->connection;
  DiaObject *obj = &conn->object;

  obj->position = conn->endpoints[0];
  connection_update_boundingbox(conn);

  /* compute the label's width and bounding box */
  condition->cond->pos.x = conn->endpoints[0].x + 
    (.5 * dia_font_string_width("a", condition->cond->font,
			    condition->cond->fontheight));
  condition->cond->pos.y = conn->endpoints[0].y + condition->cond->fontheight;
  
  boolequation_calc_boundingbox(condition->cond, &condition->labelbb);
  rectangle_union(&obj->bounding_box,&condition->labelbb);

  connection_update_handles(conn);
}


static void 
condition_draw(Condition *condition, DiaRenderer *renderer)
{
  DiaRendererClass *renderer_ops = DIA_RENDERER_GET_CLASS (renderer);
  Connection *conn = &condition->connection;

  renderer_ops->set_linewidth(renderer, CONDITION_LINE_WIDTH);
  renderer_ops->set_linestyle(renderer, LINESTYLE_SOLID);
  renderer_ops->set_linecaps(renderer, LINECAPS_BUTT);

  if (CONDITION_ARROW_SIZE > (CONDITION_LINE_WIDTH/2.0)) {
    Arrow arrow;
    arrow.type = ARROW_FILLED_TRIANGLE;
    arrow.width = CONDITION_ARROW_SIZE;
    arrow.length = CONDITION_ARROW_SIZE/2;
    renderer_ops->draw_line_with_arrows(renderer,
					 &conn->endpoints[0],&conn->endpoints[1],
					 CONDITION_LINE_WIDTH,
					 &color_black,
					 &arrow, NULL);
  } else {
    renderer_ops->draw_line(renderer,
			     &conn->endpoints[0],&conn->endpoints[1],
			     &color_black);
  }

  boolequation_draw(condition->cond,renderer);
}

static DiaObject *
condition_create(Point *startpoint,
		  void *user_data,
		  Handle **handle1,
		  Handle **handle2)
{
  Condition *condition;
  Connection *conn;
  LineBBExtras *extra;
  DiaObject *obj;
  Point defaultlen  = {0.0,CONDITION_ARROW_SIZE}, pos;

  DiaFont *default_font; 
  real default_fontheight;
  Color fg_color;

  condition = g_malloc0(sizeof(Condition));
  conn = &condition->connection;
  obj = &conn->object;
  extra = &conn->extra_spacing;

  obj->type = &condition_type;
  obj->ops = &condition_ops;
  
  point_copy(&conn->endpoints[0],startpoint);
  point_copy(&conn->endpoints[1],startpoint);
  point_add(&conn->endpoints[1], &defaultlen);

  connection_init(conn, 2,0);

  pos = conn->endpoints[1];

  default_font = NULL;
  attributes_get_default_font(&default_font,&default_fontheight);
  fg_color = attributes_get_foreground();
  
  condition->cond = boolequation_create("",default_font,default_fontheight,
				 &fg_color);
  condition->cond_value = g_strdup("");
  condition->cond_font = dia_font_ref(default_font);
  condition->cond_fontheight = default_fontheight;
  condition->cond_color = fg_color;

  extra->start_trans = 
    extra->start_long = 
    extra->end_long = CONDITION_LINE_WIDTH/2.0;
  extra->end_trans = MAX(CONDITION_LINE_WIDTH,CONDITION_ARROW_SIZE) / 2.0;

  condition_update_data(condition);

  conn->endpoint_handles[0].connect_type = HANDLE_NONCONNECTABLE;
  *handle1 = &conn->endpoint_handles[0];
  *handle2 = &conn->endpoint_handles[1];

  dia_font_unref(default_font);

  return &condition->connection.object;
}

static void
condition_destroy(Condition *condition)
{
  dia_font_unref(condition->cond_font);  
  boolequation_destroy(condition->cond);
  g_free(condition->cond_value);
  connection_destroy(&condition->connection);
}

static DiaObject *
condition_load(ObjectNode obj_node, int version, const char *filename)
{
  return object_load_using_properties(&condition_type,
                                      obj_node,version,filename);
}








