/* pie.c 
 *
 * function defined:
 *
 * pie(dist_stats,colors) 
 *
 * struct stat_list *dist_stats     - linked list of statistics
 * struct Colors *colors            - map colors
 *
 * 
 * PURPOSE: To draw a pie-chart representing the histogram
 * statistics in the linked list dist_stats.  
 *
 * NOTES: 
 *
 * 1) see dhist.h for a decalaration of the structure stat_list.  
 * 2) see pie.h for normalized coordinates of the different parts
 *    of the pie-chart, like the origin of the pie, the label
 *    positions, etc.
 * 3) pie slices are given percent labels (eg. 20%, 70%) if they
 *    represent over 15% of the pie.
 *
 *
 * Dave Johnson
 * DBA Systems, Inc.
 * 10560 Arrowhead Drive
 * Fairfax, Virginia 22030
 *
 */

#include <string.h>
#include <grass/display.h>
#include <grass/raster.h>
#include "pie.h"

/*#define DEBUG*/

#define YES	1
#define NO	0


int 
pie (
    struct stat_list *dist_stats,  /* list of distribution statistics */
    struct Colors *colors
)
{
struct stat_node *ptr;
double arc,
       arc_counter;
int    draw=YES;
long int bar_height;     /* height, in pixels, of a histogram bar */
long int bar_color;      /* color/category number of a histogram bar */
long int max_tics;       /* maximum tics allowed on an axis */
long int xoffset;        /* offset for x-axis */
long int yoffset;        /* offset for y-axis */
int      text_height;
int      text_width;
long int i, j;
long int num_cats;
long int num_stats = 0;
long int tic_every;       /* spacing, in units of category value, of tics */ 
long int tic_unit;      
int t, b, l, r;
int tt, tb, tl, tr;
int x_line[5];            /* for border of histogram */
int y_line[5];
int x_box[6];             /* for histogram bar coordinates */
int y_box[6];         
double height, width;
double xscale;            /* scaling factors */
double yscale;
char xlabel[1024];
char ylabel[1024];
char txt[1024];
char tic_name[80];
DCELL dmin, dmax, range_dmin, range_dmax, dval;

/* get coordinates of current screen window, in pixels */
D_get_screen_window(&t, &b, &l, &r) ;
R_set_window(t, b, l, r) ;

/* create legend box border, to be drawn later */
height = b-t;
width = r-l;
x_line[4] = x_line[0] = x_line[1] = l+(int)(BAR_X1*width);        
y_line[4] = y_line[0] = y_line[3] = b-(int)(BAR_Y1*height);      
x_line[2] = x_line[3] = l+(int)(BAR_X2*width);
bar_height = y_line[1] = y_line[2] = b-(int)(BAR_Y2*height);

/* figure scaling factors and offsets */
num_cats = dist_stats->maxcat - dist_stats->mincat+1;
if(nodata)
{
    num_cats++;
    dist_stats->mincat--;
}
xscale = ((double)(x_line[2]-x_line[1])/((double)num_cats));
yscale = ((double)(y_line[0]-y_line[1]))/dist_stats->maxstat;
yoffset = (long)(y_line[0]);
if (num_cats >= x_line[2]-x_line[1]) 
   xoffset = (double)x_line[1];             
else
   xoffset = (double)x_line[0]+0.5*xscale;  /* boxes need extra space */ 

#ifdef DEBUG
fprintf (stdout,"num_cats=%ld x1=%d x2=%d xscale=%lf\n",
       num_cats,x_line[1],x_line[2],xscale);
#endif

/* figure tic_every and tic_units for the x-axis of the bar-chart.
 * tic_every tells how often to place a tic-number.  tic_unit tells
 * the unit to use in expressing tic-numbers.
 */
if (xscale < XTIC_DIST)
   {
   max_tics = (x_line[2]-x_line[1])/XTIC_DIST;
   i=0;
   if(is_fp)
   {
      G_get_fp_range_min_max (&fp_range, &range_dmin, &range_dmax);
      if(G_is_d_null_value(&range_dmin) || G_is_d_null_value(&range_dmax))
          G_fatal_error("Floating point data range is empty");

      while((range_dmax - range_dmin)/tics[i].every > max_tics)
	   i++;
   }

   while ((num_cats/tics[i].every) > max_tics)
      i++;
   tic_every = tics[i].every;
   tic_unit = tics[i].unit;
   strcpy(tic_name,tics[i].name);
   }
else
   {
   if(is_fp && !cat_ranges)
   {
      G_get_fp_range_min_max (&fp_range, &range_dmin, &range_dmax);
      if(G_is_d_null_value(&range_dmin) || G_is_d_null_value(&range_dmax))
          G_fatal_error("Floating point data range is empty");
   }
   tic_every = 1;
   tic_unit = 1;
   }

/* PIE & LEGEND LOOP 
 *
 * loop through category range, drawing a pie-slice and a
 * legend bar on each iteration evenly divisible, a tic-mark
 * on those evenly divisible by tic_unit, and a tic_mark
 * number on those evenly divisible by tic_every
 *
 */
ptr = dist_stats->ptr;
arc_counter = 0;
for (i=dist_stats->mincat; i<=dist_stats->maxcat; i++)
   {
   text_height = (height)*0.7*TEXT_HEIGHT;
   text_width = (width)*0.7*TEXT_WIDTH; 
   R_text_size(text_width,text_height);
   draw=NO;
   /* figure color and height of the slice of pie 
    *
    * the cat number determines the color, the corresponding stat,
    * determines the bar height.  if a stat cannot be found for the
    * cat, then we don't draw anything, but before in this case we
    * used to draw a black box of size 0. Later on when the option 
    * to specify the backgrown colors will be added, we might still
    * draw a box in that color.
    */
   if(nodata && i==dist_stats->mincat)
   /* null */
   {
	 if (dist_stats->null_stat == 0 && xscale > 1)
	      draw=NO;
         else
	 {
	      draw=YES;
	      G_set_d_null_value(&dval,1);
	      arc = (double)360*((double)dist_stats->null_stat
				       /(double)dist_stats->sumstat);
              draw_slice_filled(colors, dval,(int)color,(double)ORIGIN_X,
                           (double)ORIGIN_Y, (double)RADIUS,arc_counter,arc);
              /*OUTLINE THE SLICE
              draw_slice_unfilled(colors, (int)color,(double)ORIGIN_X,(double)ORIGIN_Y,
                             (double)RADIUS,arc_counter,arc);*/
              arc_counter += arc;
              D_d_color(dval, colors);
         }
   }
   else if (ptr->cat == i) /* AH-HA!! found the stat */
      {
      if (ptr->stat == 0 && xscale > 1)
         draw=NO;
      else
         {
         draw=YES;
	 if(is_fp)
	 {
	    if(cat_ranges)
	        G_get_ith_d_raster_cat(&cats, (CELL) i, &dmin, &dmax);
            else
	    {
	     dmin=range_dmin+(double)i*(range_dmax-range_dmin)/(double)nsteps;
	     dmax=range_dmin+(double)(i+1)*(range_dmax-range_dmin)/(double)nsteps;
	    }
            arc = (double)360*((double)ptr->stat/(double)dist_stats->sumstat);
            draw_slice(colors, 1, dmin, dmax, (int)color,(double)ORIGIN_X,
                           (double)ORIGIN_Y, (double)RADIUS,arc_counter,arc);
            arc_counter += arc;
	    D_d_color(dmin, colors);
            /*OUTLINE THE SLICE */
            draw_slice_unfilled(colors, (int)color,(double)ORIGIN_X,(double)ORIGIN_Y,
                             (double)RADIUS,arc_counter,arc);
         }
	 else
	 {
              bar_color = ptr->cat; 
              arc = (double)360*((double)ptr->stat/(double)dist_stats->sumstat);
              draw_slice_filled(colors, (DCELL)bar_color,(int)color,(double)ORIGIN_X,
                           (double)ORIGIN_Y, (double)RADIUS,arc_counter,arc);
              D_color((CELL)bar_color, colors);
              arc_counter += arc;
         }
	 }
      if (ptr->next != NULL)
         ptr=ptr->next;
      }
   else /* we have to look for the stat */
      {
      /* loop until we find it, or pass where it should be */ 
      while (ptr->cat < i && ptr->next != NULL)
         ptr = ptr->next;
      if (ptr->cat == i) /* AH-HA!! found the stat */
      {
         if (ptr->stat == 0 && xscale > 1)
            draw=NO;
         else
         {
         draw=YES;
	 if(is_fp)
	 {
	    if(cat_ranges)
	        G_get_ith_d_raster_cat(&cats, (CELL) i, &dmin, &dmax);
            else
	    {
	     dmin=range_dmin+(double)i*(range_dmax-range_dmin)/(double)nsteps;
	     dmax=range_dmin+(double)(i+1)*(range_dmax-range_dmin)/(double)nsteps;
	    }
            arc = (double)360*((double)ptr->stat/(double)dist_stats->sumstat);
            draw_slice(colors, 1, dmin, dmax, (int)color,(double)ORIGIN_X,
                           (double)ORIGIN_Y, (double)RADIUS,arc_counter,arc);
            arc_counter += arc;
            /*OUTLINE THE SLICE */
            draw_slice_unfilled(colors, (int)color,(double)ORIGIN_X,(double)ORIGIN_Y,
                             (double)RADIUS,arc_counter,arc);
	    D_d_color(dmin, colors);
         }
	 else
	 {
              bar_color = ptr->cat; 
              arc = (double)360*((double)ptr->stat/(double)dist_stats->sumstat);
              draw_slice_filled(colors, (DCELL)bar_color,(int)color,(double)ORIGIN_X,
                           (double)ORIGIN_Y, (double)RADIUS,arc_counter,arc);
              D_color((CELL)bar_color, colors);
              arc_counter += arc;
         }
      }
      }
      else /* stat cannot be found */
         {
         if (xscale > 1)
            {
	    /*
            draw=YES;
	    */
            draw=NO;
            bar_color = D_translate_color("black");  
            R_standard_color(bar_color);
            }
         else
            draw=NO;
         }
      }

   /* draw the bar */
   if (draw==YES)
      {
      if (xscale != 1)
         {
         /* draw the bar as a box */

            /* if fp map and not null and range is not empty, draw smooth 
	       color range */
	    if(is_fp && !(i==dist_stats->mincat && nodata) & dmin != dmax)
	    {
		 for(j=0; j < xscale; j++)
		 {
		    dval = dmin + j * (dmax-dmin)/ xscale;
		    D_d_color(dval, colors);
		    x_box[0]= x_box[1] = xoffset+((i-dist_stats->mincat)*xscale-0.5*xscale + j);
		    x_box[2]= x_box[3] = xoffset+((i-dist_stats->mincat)*xscale-0.5*xscale + j + 1);
                    y_box[0] = y_box[3] = y_box[4] = y_line[0]; 
                    y_box[1] = y_box[2] = bar_height; 
                    R_polygon_abs(x_box,y_box,4);
                 }
	    }
	    else /* draw 1-color bar, color is already set */
	    {
	         x_box[0]= x_box[1] = xoffset+((i-dist_stats->mincat)*xscale-0.5*xscale);
	         x_box[2]= x_box[3] = xoffset+((i-dist_stats->mincat)*xscale+0.5*xscale);
                 y_box[0] = y_box[3] = y_box[4] = y_line[0]; 
                 y_box[1] = y_box[2] = bar_height; 
                 R_polygon_abs(x_box,y_box,4);
            }
         }
      else /* color is already set for 1-color bar */
         {
         /* draw the bar as a line */
         x_box[0] = x_box[1] = xoffset+(i-dist_stats->mincat)*xscale; 
         y_box[0] = yoffset;
         y_box[1] = bar_height;
         R_move_abs((int)x_box[0],(int)y_box[0]);
         R_cont_abs((int)x_box[1],(int)y_box[1]);
         }
      }
 
   /* draw x-axis tic-marks and numbers */
   /* draw tick for null and for numbers at every tic step
      except when there is null, don't draw tic for mincat+1 */

   if ((rem((long int)i,tic_every)==(float)0 ||
	      i==dist_stats->mincat && nodata)
       && !(nodata && i==dist_stats->mincat+1))
      {
      /* draw a numbered tic-mark */
      R_standard_color(color);
      R_move_abs( (int)(xoffset+(i-dist_stats->mincat)*xscale - 0.5 * xscale),
                  (int)(b-BAR_Y1*(height)) );
      R_cont_rel( (int)0 , (int)(BIG_TIC*(height)) );
      if(nodata && i==dist_stats->mincat)
	 sprintf(txt, "null");
      else if(is_fp)
         sprintf(txt,"%d",(int) (dmin/(double) tic_unit));
      else
         sprintf(txt,"%d",(int) (i/tic_unit));
      text_height = (height)*TEXT_HEIGHT;
      text_width = (width)*TEXT_WIDTH;
      R_text_size(text_width,text_height);
      R_get_text_box(txt,&tt,&tb,&tl,&tr);
      while ((tr-tl) > XTIC_DIST)
         {
         text_width *= 0.95;
         text_height *= 0.95;
         R_text_size(text_width,text_height);
         R_get_text_box(txt,&tt,&tb,&tl,&tr);
         }
      R_move_abs((int)(xoffset+(i-dist_stats->mincat)*xscale - 0.5 * xscale-(tr-tl)/2),
                 (int)(b-XNUMS_Y*(height)));
      R_text(txt);
      }
   else if (rem(i,tic_unit)==(float)0) 
      {
      /* draw a tic-mark */
      R_standard_color((int)color);
      R_move_abs( (int)(xoffset+(i-dist_stats->mincat)*xscale - 0.5 * xscale),
                  (int)(b-BAR_Y1*(height)) );
      R_cont_rel( (int)0 , (int)(SMALL_TIC*(height)) );
      }
   }

/* draw border around pie */
R_standard_color((int)color);
draw_slice_unfilled(colors, (int)color,(double)ORIGIN_X,(double)ORIGIN_Y,
                   (double)RADIUS,(double)0,(double)360);

/* draw border around legend bar */
R_standard_color((int)color);
R_polyline_abs(x_line,y_line,5);

/* draw the x-axis label */
if (tic_unit != 1)
   sprintf(xlabel,"Cell Values %s",tic_name);
else
   sprintf(xlabel,"Cell Values");
text_height = (height)*TEXT_HEIGHT;
text_width = (width)*TEXT_WIDTH; 
R_text_size(text_width,text_height);
R_get_text_box(xlabel,&tt,&tb,&tl,&tr);
R_move_abs( (int) (l+(width)/2-(tr-tl)/2) , (int) (b-LABEL*(height)) );
R_standard_color((int)color);
R_text(xlabel);

	return 0;
}