#include <grass/gis.h>
#include <grass/Vect.h>
#include <grass/dbmi.h>
#include <grass/display.h>
#include <grass/raster.h>
#include <grass/symbol.h>
#include "global.h"

int 
bar ( double cx, double cy, int size, double scale, double *val, int ncols, COLOR *ocolor, COLOR *colors, int y_center, double *max_reference ) 
{
    int i, j;
    double max;
    double x0, y0;
    double bw; /* bar width */
    double pixel; /* pixel size */
    struct line_pnts *Points, *max_Points;

    G_debug (4, "bar(): cx = %f cy = %f", cx, cy );
    
    Points = Vect_new_line_struct ();
    max_Points = Vect_new_line_struct ();

    pixel = D_d_to_u_col(2) - D_d_to_u_col(1); /* do it better */
    
    /* Bottom (y0) */
    max = 0;
    for ( i = 0; i < ncols; i++ ) { 
	if ( val[i] > max) max = val[i]; 
    };
    
    /* debug */
    /* printf("%f \n", max_reference); */
    
    if(y_center == 0) /* draw the columns with the bottom at the y value of the point  */
		y0 = cy ; 
	else
		y0 = cy - scale * max * pixel / 2;	/* center the columns around the y value of the point */
    
    /* Left (x0) */
    x0 = cx - size * pixel / 2;

    bw = size * pixel / ncols;
	
	if(max_reference) {
		/* Draw polygon outlining max value in dataset with no fill color*/
		for ( i = 0; i < ncols; i++ ) {
		Vect_reset_line ( max_Points );
		Vect_append_point ( max_Points, x0 + i*bw, y0, 0);
		Vect_append_point ( max_Points, x0 + (i+1)*bw, y0, 0);
		Vect_append_point ( max_Points, x0 + (i+1)*bw, y0 + scale * max_reference[i] * pixel, 0);
		Vect_append_point ( max_Points, x0 + i*bw, y0 + scale * max_reference[i] * pixel, 0);
		Vect_append_point ( max_Points, x0 + i*bw, y0, 0);
		
		
		/* the outline color : default is black*/
		R_RGB_color ( ocolor->r, ocolor->g, ocolor->b );
		for (j = 1; j < max_Points->n_points; j++ ) { 
			G_plot_line(max_Points->x[j], max_Points->y[j], max_Points->x[j-1], max_Points->y[j-1]);
		}
		}
	}
	
    /* Draw polygon for each value */
    for ( i = 0; i < ncols; i++ ) {
	Vect_reset_line ( Points );
	Vect_append_point ( Points, x0 + i*bw, y0, 0);
	Vect_append_point ( Points, x0 + (i+1)*bw, y0, 0);
	Vect_append_point ( Points, x0 + (i+1)*bw, y0 + scale * val[i] * pixel, 0);
	Vect_append_point ( Points, x0 + i*bw, y0 + scale * val[i] * pixel, 0);
	Vect_append_point ( Points, x0 + i*bw, y0, 0);

	if(!colors[i].none) {
	    R_RGB_color ( colors[i].r, colors[i].g, colors[i].b );
	    G_plot_polygon ( Points->x, Points->y, Points->n_points);
	}

	R_RGB_color ( ocolor->r, ocolor->g, ocolor->b );
	for (j = 1; j < Points->n_points; j++ ) { 
	    G_plot_line(Points->x[j], Points->y[j], Points->x[j-1], Points->y[j-1]);
	}
    }

	/* tidy up */
    Vect_destroy_line_struct (Points);
    Vect_destroy_line_struct (max_Points);

    return 0;
}