/*
 * $Header: /cvsroot/pgsql/src/test/regress/regress.c,v 1.13 1997/09/08 21:56:01 momjian Exp $
 */

#include <float.h>				/* faked on sunos */
#include <stdio.h>
#include <string.h>				/* for memset() */

#include <postgres.h>

#include "utils/geo_decls.h"	/* includes <math.h> */
#include "executor/executor.h"	/* For GetAttributeByName */

#define P_MAXDIG 12
#define LDELIM			'('
#define RDELIM			')'
#define DELIM			','

typedef void *TUPLE;

extern double *regress_dist_ptpath(Point *pt, PATH *path);
extern double *regress_path_dist(PATH *p1, PATH *p2);
extern PATH *poly2path(POLYGON *poly);
extern Point *interpt_pp(PATH *p1, PATH *p2);
extern void regress_lseg_construct(LSEG *lseg, Point *pt1, Point *pt2);
extern char overpaid(TUPLE tuple);
extern int	boxarea(BOX *box);
extern char *reverse_c16(char *string);

/*
** Distance from a point to a path
*/
double	   *
regress_dist_ptpath(pt, path)
Point	   *pt;
PATH	   *path;
{
	double	   *result;
	double	   *tmp;
	int			i;
	LSEG		lseg;

	switch (path->npts)
	{
		case 0:
			result = PALLOCTYPE(double);
			*result = Abs((double) DBL_MAX);	/* +infinity */
			break;
		case 1:
			result = point_distance(pt, &path->p[0]);
			break;
		default:

			/*
			 * the distance from a point to a path is the smallest
			 * distance from the point to any of its constituent segments.
			 */
			Assert(path->npts > 1);
			result = PALLOCTYPE(double);
			for (i = 0; i < path->npts - 1; ++i)
			{
				regress_lseg_construct(&lseg, &path->p[i], &path->p[i + 1]);
				tmp = dist_ps(pt, &lseg);
				if (i == 0 || *tmp < *result)
					*result = *tmp;
				PFREE(tmp);

			}
			break;
	}
	return (result);
}

/* this essentially does a cartesian product of the lsegs in the
   two paths, and finds the min distance between any two lsegs */
double	   *
regress_path_dist(p1, p2)
PATH	   *p1;
PATH	   *p2;
{
	double	   *min,
			   *tmp;
	int			i,
				j;
	LSEG		seg1,
				seg2;

	regress_lseg_construct(&seg1, &p1->p[0], &p1->p[1]);
	regress_lseg_construct(&seg2, &p2->p[0], &p2->p[1]);
	min = lseg_distance(&seg1, &seg2);

	for (i = 0; i < p1->npts - 1; i++)
		for (j = 0; j < p2->npts - 1; j++)
		{
			regress_lseg_construct(&seg1, &p1->p[i], &p1->p[i + 1]);
			regress_lseg_construct(&seg2, &p2->p[j], &p2->p[j + 1]);

			if (*min < *(tmp = lseg_distance(&seg1, &seg2)))
				*min = *tmp;
			PFREE(tmp);
		}

	return (min);
}

PATH	   *
poly2path(poly)
POLYGON    *poly;
{
	int			i;
	char	   *output = (char *) PALLOC(2 * (P_MAXDIG + 1) * poly->npts + 64);
	char		buf[2 * (P_MAXDIG) + 20];

	sprintf(output, "(1, %*d", P_MAXDIG, poly->npts);

	for (i = 0; i < poly->npts; i++)
	{
		sprintf(buf, ",%*g,%*g", P_MAXDIG, poly->p[i].x, P_MAXDIG, poly->p[i].y);
		strcat(output, buf);
	}

	sprintf(buf, "%c", RDELIM);
	strcat(output, buf);
	return (path_in(output));
}

/* return the point where two paths intersect.	Assumes that they do. */
Point	   *
interpt_pp(p1, p2)
PATH	   *p1;
PATH	   *p2;
{

	Point	   *retval;
	int			i,
				j;
	LSEG		seg1,
				seg2;

#if FALSE
	LINE	   *ln;

#endif
	bool		found;			/* We've found the intersection */

	found = false;				/* Haven't found it yet */

	for (i = 0; i < p1->npts - 1 && !found; i++)
		for (j = 0; j < p2->npts - 1 && !found; j++)
		{
			regress_lseg_construct(&seg1, &p1->p[i], &p1->p[i + 1]);
			regress_lseg_construct(&seg2, &p2->p[j], &p2->p[j + 1]);
			if (lseg_intersect(&seg1, &seg2))
				found = true;
		}

#if FALSE
	ln = line_construct_pp(&seg2.p[0], &seg2.p[1]);
	retval = interpt_sl(&seg1, ln);
#endif
	retval = lseg_interpt(&seg1, &seg2);

	return (retval);
}


/* like lseg_construct, but assume space already allocated */
void
regress_lseg_construct(lseg, pt1, pt2)
LSEG	   *lseg;
Point	   *pt1;
Point	   *pt2;
{
	lseg->p[0].x = pt1->x;
	lseg->p[0].y = pt1->y;
	lseg->p[1].x = pt2->x;
	lseg->p[1].y = pt2->y;
	lseg->m = point_sl(pt1, pt2);
}


char
overpaid(tuple)
TUPLE		tuple;
{
	bool		isnull;
	long		salary;

	salary = (long) GetAttributeByName(tuple, "salary", &isnull);
	return (salary > 699);
}

/* New type "widget"
 * This used to be "circle", but I added circle to builtins,
 *	so needed to make sure the names do not collide. - tgl 97/04/21
 */

typedef struct
{
	Point		center;
	double		radius;
}			WIDGET;

WIDGET	   *widget_in(char *str);
char	   *widget_out(WIDGET * widget);
int			pt_in_widget(Point *point, WIDGET * widget);

#define NARGS	3

WIDGET	   *
widget_in(str)
char	   *str;
{
	char	   *p,
			   *coord[NARGS],
				buf2[1000];
	int			i;
	WIDGET	   *result;

	if (str == NULL)
		return (NULL);
	for (i = 0, p = str; *p && i < NARGS && *p != RDELIM; p++)
		if (*p == ',' || (*p == LDELIM && !i))
			coord[i++] = p + 1;
	if (i < NARGS - 1)
		return (NULL);
	result = (WIDGET *) palloc(sizeof(WIDGET));
	result->center.x = atof(coord[0]);
	result->center.y = atof(coord[1]);
	result->radius = atof(coord[2]);

	sprintf(buf2, "widget_in: read (%f, %f, %f)\n", result->center.x,
			result->center.y, result->radius);
	return (result);
}

char	   *
widget_out(widget)
WIDGET	   *widget;
{
	char	   *result;

	if (widget == NULL)
		return (NULL);

	result = (char *) palloc(60);
	sprintf(result, "(%g,%g,%g)",
			widget->center.x, widget->center.y, widget->radius);
	return (result);
}

int
pt_in_widget(point, widget)
Point	   *point;
WIDGET	   *widget;
{
	extern double point_dt();

	return (point_dt(point, &widget->center) < widget->radius);
}

#define ABS(X) ((X) > 0 ? (X) : -(X))

int
boxarea(box)

BOX		   *box;

{
	int			width,
				height;

	width = ABS(box->high.x - box->low.x);
	height = ABS(box->high.y - box->low.y);
	return (width * height);
}

char	   *
reverse_c16(string)
char	   *string;
{
	register	i;
	int			len;
	char	   *new_string;

	if (!(new_string = palloc(16)))
	{
		fprintf(stderr, "reverse_c16: palloc failed\n");
		return (NULL);
	}
	memset(new_string, 0, 16);
	for (i = 0; i < 16 && string[i]; ++i)
		;
	if (i == 16 || !string[i])
		--i;
	len = i;
	for (; i >= 0; --i)
		new_string[len - i] = string[i];
	return (new_string);
}
