/*
 * Converted code from legend.c in SG3d
 * routines to set viewport, close viewport, and make legend
*/

#include <stdlib.h>
#include <stdio.h>

#include <grass/config.h>

#if defined(OPENGL_X11) || defined(OPENGL_WINDOWS)
#include <GL/gl.h>
#include <GL/glu.h>
#elif defined(OPENGL_AQUA)
#include <OpenGL/gl.h>
#include <OpenGL/glu.h>
#endif

#include <grass/gis.h>
#include <grass/gstypes.h>
#include "rgbpack.h"


static float *Listcats;
static int Listnum = 0;


/**** TODO
static int bigger(float *f1, float *f2)
{
    return (*f1 < *f2 ? -1 : (*f1 > *f2));
}
*****/

#define MAX_LEGEND 256

/*****************************************************************/
void gsd_bgn_legend_viewport(GLint wl, GLint wb, GLint wr, GLint wt)
{
/* sets the viewport for the legend and the model matrix */

    gsd_colormode(CM_COLOR);
    glPushAttrib(GL_VIEWPORT);

    glMatrixMode(GL_PROJECTION);

    gsd_pushmatrix();
    GS_set_draw(GSD_FRONT);
    GS_ready_draw();

    gsd_linewidth(1);

    gsd_popmatrix();

    glViewport(wl, wb, (wr - wl), (wt - wb));
    glLoadIdentity();
    gluOrtho2D(-0.5, (wr - wl) + 0.5, -0.5, (wt - wb) + 0.5);
    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glLoadIdentity();

    return;
}


/***********************************************/
void gsd_end_legend_viewport(void)
{
/* closes the legend viewport and resets matrix and buffers */

    gsd_popmatrix();
    glMatrixMode(GL_PROJECTION);
    gsd_popmatrix();

    glPopAttrib();
    glMatrixMode(GL_MODELVIEW);
    gsd_popmatrix();

    GS_done_draw();
    GS_set_draw(GSD_BACK);
    
    return;
}


/*****************************************************************/
int gsd_get_nice_range(float lownum, float highnum, int numvals, float *vals)
{
/* get a nice range for displaying legend */

    int num = 0;
    float curnum, step, start;

    if (!numvals)
	return (0);

    step = (highnum - lownum) / (float) numvals;
    gsd_make_nice_number(&step);

    /* get a starting point */
    start = step * (int) (1 + lownum / step);
    if (start - lownum < .65 * step)
	start += step;

    for (curnum = start; curnum < (highnum - .65 * step); curnum += step) {
	vals[num++] = curnum;
    }

    return (num);

}


/*****************************************************************/
int gsd_make_nice_number(float *num)
{
    float newnum, nextnum;

    if (*num < 0)
	return (0);

    if (*num < 1) {
	newnum = 1.;
	while (.5 * newnum > *num) {
	    nextnum = newnum / 10.;
	    newnum /= 2.;
	    if (.5 * newnum > *num)
		newnum /= 2.;
	    if (.5 * newnum > *num)
		newnum = nextnum;
	}
    }
    else {
	newnum = 1.;
	while (2 * newnum <= *num) {
	    nextnum = newnum * 10.;
	    newnum *= 2.5;
	    if (2 * newnum <= *num)
		newnum *= 2.;
	    if (2 * newnum <= *num)
		newnum = nextnum;
	}
	if (newnum == 2.5)
	    newnum = 3;
	/* 2.5 isn't nice, but .25, 25, 250 ... are */
    }
    *num = newnum;
    return (1);
}


/*****************************************************************/
GLuint
gsd_put_legend(char *name, GLuint fontbase, int size, int *flags,
	       float *rangef, int *pt)
{
    GLint sl, sr, sb, st;
    GLuint legend_list;
    int cat_labs = 0, cat_vals = 0, do_invert = 0, discrete = 0;
    int is_fp, fprec, iprec;
    struct Categories cats;
    struct Range range;
    struct FPRange fp_range;
    char *mapset;
    struct Colors colors;
    CELL min, max;
    DCELL fmin, fmax;
    float labvals[12];

    legend_list = gsd_makelist();
    gsd_bgnlist(legend_list, 1);

/* set coords from pt */
    sl = pt[0];
    sr = pt[1];
    sb = pt[2];
    st = pt[3];

/* set legend flags */
    if (flags[0])
	cat_vals = 1;
    if (flags[1])
	cat_labs = 1;
    if (flags[3])
	discrete = 1;
    if (flags[2])
	do_invert = 1;

    mapset = G_find_cell(name, "");
    if (mapset == NULL) {
	fprintf(stderr, "Unable to locate raster %s\n", name);
	return (-1);
    }

    is_fp = G_raster_map_is_fp(name, mapset);

    if (G_read_colors(name, mapset, &colors) == -1) {
	fprintf(stderr, "Color file for [%s] not available\n", name);
	return (-1);
    }

    if (cat_labs)
	if (G_read_cats(name, mapset, &cats) == -1) {
	    fprintf(stderr, "Category file for [%s] not available\n", name);
	    cat_labs = 0;
	}


    if (flags[4] && rangef[0] != -9999. && rangef[1] != -9999.) {
	fmin = rangef[0];
	fmax = rangef[1];
	if (!is_fp) {
		min = (int)fmin;
		max = (int)fmax;
	}
    }
    else {
	if (is_fp) {
	    if (G_read_fp_range(name, mapset, &fp_range) != 1) {
		fprintf(stderr, "Range info for [%s] not available\n", name);
		return(-1);
	    }
	    G_get_fp_range_min_max(&fp_range, &fmin, &fmax);
	    if (flags[4] && rangef[0] != -9999.)
		fmin = rangef[0];
	    if (flags[4] && rangef[1] != -9999.)
		fmax = rangef[1];
	}
	else {
	    if (G_read_range(name, mapset, &range) == -1) {
		fprintf(stderr, "Range info for [%s] not available\n", name);
		return (-1);
	    }
	    G_get_range_min_max(&range, &min, &max);
	    if (flags[4] && rangef[0] != -9999.)
		min = rangef[0];
	    if (flags[4] && rangef[1] != -9999.)
		max = rangef[1];
	    fmin = min;
	    fmax = max;
	}
    }

    if (fmin == fmax)
	Gs_warning("Range request error for legend");

    /* set a reasonable precision */
    if (is_fp) {
	float df;

	df = fmax - fmin;
	if (df < .1)
	    fprec = 6;
	else if (df < 1)
	    fprec = 4;
	else if (df < 10)
	    fprec = 3;
	else if (df < 100)
	    fprec = 2;
	else
	    fprec = 1;

    }
    else {
	int tmp, p1, p2;

	iprec = p1 = p2 = 1;
	if (max > 0)
	    for (tmp = 1; tmp < max; tmp *= 10, p1++);
	if (min < 0)
	    for (tmp = -1; tmp > min; tmp *= 10, p2++);

	iprec = (p1 > p2 ? p1 : p2);
    }

/*********
 * TODO incorp lists

     if(list && (legend_type & LT_LIST)){
	Listcats = list;
	Listnum = nlist;
	qsort(Listcats, Listnum, sizeof(float), bigger);
	discrete = 1;   
    }
    else
	Listnum = 0;

*********/


/* how many labels? */
/*
numlabs can't be = max - min + 1 any more because of floating point
maybe shouldn't allow discrete legend for floating point maps (unless list)
or else check number of different values in floating point map
and use each if "reasonable"
gs_get_values_in_range(gs, att, low, high, values, &nvals)
the nvals sent has a max number to return, nvals returned is the actual
number set in values, return val is 1 on success, -1 if > max vals found

might need to think about doing histograms first & use same routines here
could also have a LT_MOST that would limit # to some N most frequent
*/

    {
	int i, k, lleg, horiz;
	int red, green, blue;
	CELL tcell;
	DCELL tdcell, pdcell;
	float vert1[2], vert2[2], vert3[2], vert4[2];
	float *dv1, *dv2;	/* changing vertex coord */
	float *sv1, *sv2;	/* stable vertex coord */
	float stab1, stab2;
	unsigned long colr;
	float *dividers;
	int labw, maxlabw, numlabs;
	float labpos, labpt[3];
	char *cstr, buff[80];
	GLint wt, wb, wl, wr;	/* Whole legend area, not just box */
	int xoff, yoff;
	int incr;		/* for do_invert */

	horiz = (sr - sl > st - sb);
	dividers = NULL;

	if (discrete) {
	    numlabs = Listnum ? Listnum : max - min + 1;
	    /* watch out for trying to display mega cats */
	    if (is_fp && !Listnum) {
		discrete = 0;	/* maybe later do stats & allow if few #s */
		fprintf(stderr,
			"Unable to show discrete FP range (use list)\n");
		return (-1);
	    }
	    if (numlabs < MAX_LEGEND)
		dividers = (float *) malloc(numlabs * sizeof(float));
	}
	else {
	    numlabs = gsd_get_nice_range(fmin, fmax, 4, labvals + 1);
	    labvals[0] = fmin;
	    labvals[numlabs + 1] = fmax;
	    numlabs += 2;
	}

	/* find longest string, reset viewport & saveunder */
	maxlabw = 0;

	if (cat_labs || cat_vals) {
	    for (k = 0; k < numlabs; k++) {
		if (is_fp) {
		    tdcell = discrete ? Listcats[k] : labvals[k];
		    if (cat_labs) {
			cstr = G_get_d_raster_cat(&tdcell, &cats);
		    }
		    if (cat_labs && !cat_vals) {
			sprintf(buff, "%s", cstr);
		    }
		    else {
			if (cat_labs && cat_vals) {
			    if (cstr)
				sprintf(buff, "%.*lf) %s",
					fprec, tdcell, cstr);
			    else
				sprintf(buff, "%.*lf", fprec, tdcell);
			}
			else if (cat_vals)
			    sprintf(buff, "%.*lf", fprec, tdcell);
		    }
		}
		else {
		    tcell = discrete ? Listnum ?
			Listcats[k] : min + k : labvals[k];
		    if (cat_labs && !cat_vals)
			sprintf(buff, "%s", G_get_cat(tcell, &cats));
		    else {
			if (cat_labs && cat_vals) {
			    cstr = G_get_cat(tcell, &cats);
			    if (cstr[0])
				sprintf(buff, "%*d) %s", iprec, tcell, cstr);
			    else
				sprintf(buff, "%d", tcell);
			}
			else if (cat_vals)
			    sprintf(buff, "%d", tcell);
		    }
		}
		labw = gsd_get_txtwidth(buff, size);
		if (labw > maxlabw) {
		    maxlabw = labw;
		}
	    }
	}

	if (horiz) {
	    xoff = maxlabw / 2 + get_txtxoffset();
	    wl = sl - xoff;
	    wr = sr + xoff;
	    yoff = 0;
	    wb = sb;
	    /*
	       wt = st + gsd_get_txtheight() + get_txtdescender() +3;
	     */
	    wt = st + gsd_get_txtheight(size) * 2 + 3;
	}
	else {
	    xoff = 0;
	    wl = sl;
	    wr = sr + maxlabw + get_txtxoffset() + 3;
	    /*
	       yoff = gsd_get_txtheight()/2 + get_txtdescender();
	     */
	    yoff = gsd_get_txtheight(size);
	    wb = sb - yoff;
	    wt = st + yoff;
	}

	/* initialize viewport */
	gsd_bgn_legend_viewport(wl, wb, wr, wt);


	vert1[X] = vert2[X] = xoff;
	vert1[Y] = vert2[Y] = yoff;
	if (horiz) {
	    lleg = sr - sl;
	    dv1 = vert1 + X;
	    dv2 = vert2 + X;
	    sv1 = vert1 + Y;
	    sv2 = vert2 + Y;
	    stab2 = vert2[Y] = st - sb + yoff;
	    stab1 = vert1[Y] = yoff;
	    if (do_invert)
		vert1[X] = vert2[X] = sr - sl + xoff;
	}
	else {
	    lleg = st - sb;
	    dv1 = vert1 + Y;
	    dv2 = vert2 + Y;
	    sv1 = vert1 + X;
	    sv2 = vert2 + X;
	    stab2 = vert2[X] = sr - sl + xoff;
	    stab1 = vert1[X] = xoff;
	    if (do_invert)
		vert1[Y] = vert2[Y] = st - sb + yoff;
	}

	if (discrete) {
	    if (numlabs > lleg / 5)
		G_warning("Too many categories to show as discrete!");
	    else if (numlabs > 1.2 * lleg / gsd_get_txtheight(size))
		G_warning("Try using smaller font!");
	}

	incr = do_invert ? -1 : 1;
	for (k = 0, i = 0; k < lleg; k++) {
	    if (discrete && Listnum)
		tdcell = Listcats[(int) ((float) k * numlabs / lleg)];
	    else {
		tcell = min + k * (max - min + 1) / lleg;
		tdcell = fmin + k * (fmax - fmin) / lleg;
		if (!is_fp)
		    tdcell = tcell;
	    }
	    if (k == 0 || tdcell != pdcell) {
		if (is_fp)
		    G_get_d_raster_color(&tdcell,
					 &red, &green, &blue, &colors);
		else
		    G_get_color((CELL) tdcell, &red, &green, &blue, &colors);

		RGB_TO_INT(red, green, blue, colr);
		if (discrete) {	/* draw black-white-black seperator */
		    if (k > 0) {
			*dv1 -= 2. * incr;
			*dv2 -= 2. * incr;
			gsd_color_func(0x0);
			gsd_bgnline();
			glVertex2fv(vert1);
			glVertex2fv(vert2);
			gsd_endline();

			*dv1 += 1. * incr;
			*dv2 += 1. * incr;
			if (dividers)
			    dividers[i++] = *dv1;

			*dv1 += 1. * incr;
			*dv2 += 1. * incr;
			gsd_color_func(0x0);
			gsd_bgnline();
			glVertex2fv(vert1);
			glVertex2fv(vert2);
			gsd_endline();

			*dv1 += 1. * incr;
			*dv2 += 1. * incr;
			pdcell = tdcell;
			continue;
		    }
		}
	    }

	    gsd_color_func(colr);
	    gsd_bgnline();
	    glVertex2fv(vert1);
	    glVertex2fv(vert2);
	    gsd_endline();
	    glFlush();
	    *dv1 += 1. * incr;
	    *dv2 += 1. * incr;
	    pdcell = tdcell;
	}

	/* Black box */
	vert1[X] = vert2[X] = 1. + xoff;
	vert1[Y] = vert4[Y] = 1. + yoff;
	vert3[X] = vert4[X] = sr - sl - 1. + xoff;
	vert3[Y] = vert2[Y] = st - sb - 1. + yoff;

	gsd_color_func(0x000000);
	gsd_bgnline();
	glVertex2fv(vert1);
	glVertex2fv(vert2);
	glVertex2fv(vert3);
	glVertex2fv(vert4);
	glVertex2fv(vert1);
	gsd_endline();

	/* White box */
	vert1[X] = vert2[X] = xoff;
	vert1[Y] = vert4[Y] = yoff;
	vert3[X] = vert4[X] = sr - sl + xoff;
	vert3[Y] = vert2[Y] = st - sb + yoff;

	gsd_color_func(0xFFFFFF);
	gsd_bgnline();
	glVertex2fv(vert1);
	glVertex2fv(vert2);
	glVertex2fv(vert3);
	glVertex2fv(vert4);
	glVertex2fv(vert1);
	gsd_endline();

	/* draw discrete dividers */
	if (dividers) {
	    gsd_color_func(0xFFFFFFFF);
	    *sv1 = stab1;
	    *sv2 = stab2;
	    for (k = 0; k < i; k++) {
		*dv1 = *dv2 = dividers[k];
		gsd_bgnline();
		glVertex2fv(vert1);
		glVertex2fv(vert2);
		gsd_endline();
	    }
	}

	if (cat_labs || cat_vals) {
	    labpt[Z] = 0;
	    for (k = 0; k < numlabs; k++) {
		if (is_fp) {
		    if (discrete && Listnum) {
			tdcell = Listcats[k];
			labpos = (k + .5) / numlabs;
		    }
		    else {
			/* show_all not supported unless Listnum */
			tdcell = labvals[k];
			labpos = (tdcell - fmin) / (fmax - fmin);
		    }
		}
		else {
		    if (discrete && Listnum) {
			tcell = Listcats[k];
			labpos = (k + .5) / numlabs;
		    }
		    else {
			tcell = discrete ? min + k : labvals[k];
			labpos = (tcell - min + .5) / (max - min + 1);
		    }
		}
		if (do_invert)
		    labpos = 1. - labpos;
		if (cat_labs) {
		    if (!is_fp)
			cstr = G_get_cat(tcell, &cats);
		    else
			cstr = G_get_d_raster_cat(&tdcell, &cats);
		}
		if (cat_labs && !cat_vals)
		    sprintf(buff, "%s", cstr);
		else {
		    if (cat_labs && cat_vals) {
			if (cstr)
			    if (is_fp)
				sprintf(buff, "%.*lf) %s",
					fprec, tdcell, cstr);
			    else
				sprintf(buff, "%*d) %s", iprec, tcell, cstr);
			else if (is_fp)
			    sprintf(buff, "%.*lf", fprec, tdcell);
			else
			    sprintf(buff, "%d", tcell);
		    }
		    else if (cat_vals)
			if (is_fp)
			    sprintf(buff, "%.*lf", fprec, tdcell);
			else
			    sprintf(buff, "%d", tcell);
		}
		if (horiz) {
		    labpt[X] = labpos * (sr - sl) + xoff -
			gsd_get_txtwidth(buff, size) / 2 - get_txtxoffset();
		    labpt[Y] =
			st - sb + yoff + 3 + gsd_get_txtheight(size) / 2;
		}
		else {
		    labpt[X] = sr - sl + xoff + get_txtxoffset() + 3;
		    /*
		       labpt[Y] = labpos * (st - sb) + yoff - 
		       gsd_get_txtheight()/2 + get_txtdescender();
		     */
		    labpt[Y] = labpos * (st - sb) + yoff -
			gsd_get_txtheight(size);
		}
		/* set color for black text -- maybe add option for color 
		 * supplied with font ??
		 */
		gsd_color_func(0x000000);
		do_label_display(fontbase, labpt, buff);
	    }
	}


	if (discrete)
	    free(dividers);
    }

    if (cat_labs)
	G_free_cats(&cats);
    G_free_colors(&colors);

    gsd_end_legend_viewport();

/*
    gsd_unset_font(fontbase);
*/

    gsd_endlist();

    return (legend_list);
}