#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include "mb_graph_engine.h"
#include "mb_types.h"
#include "mb_redraw_man.h"

/*! \brief Implement respective objects for SVG path tag.
 *
 * In user_data or dev_data, 0x00 bytes are padding after commands.
 * No commands other than 0x00 can resident after 0x00 itself.
 * It means command processing code can skip commands after a 0x00.
 *
 * Shapes should check if shape_t::geo is assigned.  Once transformation
 * matrics are changed, shape objects should update shape_t::geo if
 * it is assigned.
 */
typedef struct _sh_path {
    shape_t shape;
    int cmd_len;
    int pnt_len;
    int float_arg_len;
    char *user_data;
    char *dev_data;		/* device space data */
} sh_path_t;
#define RESERVED_AIXS sizeof(co_aix[2])

#define ASSERT(x)
#define SKIP_SPACE(x) while(*(x) && (isspace(*(x)) || *(x) == ',')) { (x)++; }
#define SKIP_NUM(x)					\
    while(*(x) &&					\
	  (isdigit(*(x)) ||				\
	   *(x) == 'e' ||				\
	   *(x) == 'E' ||				\
	   *(x) == '-' ||				\
	   *(x) == '+' ||				\
	   *(x) == '.'))  {					\
	(x)++;						\
    }
#define OK 0
#define ERR -1
#define PI 3.1415926535897931

#ifdef UNITTEST
#undef rdman_shape_man
#define rdman_shape_man(x, y)
#endif

/* ============================================================
 * Implement arc in path.
 */
#include <math.h>
/*! \brief Calculate center of the ellipse of an arc.
 *
 * Origin of our coordination is left-top corner, and y-axis are grown
 * to down-side.
 *
 * Space of the arc is transformed to space that correspondent
 * ellipse containing the arc is mapped into an unit circle.
 * - ux0 = x0 / rx
 * - uy0 = y0 / ry
 * - ux = x / rx
 * - uy = y / ry
 * ux0, uy0, ux, uy are got by transforming (x0, y0) and (x, y) into points
 * on the unit circle. The center of unit circle are (ucx, ucy):
 * - umx = (ux0 + ux) / 2
 * - umy = (uy0 + uy) / 2
 * - udcx = ucx - umx
 * - udcy = ucy - umy
 * - udx = ux - umx
 * - udy = uy - umy
 *
 * - udx * udcx + udy * udcy = 0
 *
 * - udl2 = udx ** 2 + udy ** 2
 *
 * For drawing small arc in clockwise
 * - udx * udcy - udy * udcx = sqrt((1 - udl2) * udl2)
 *
 * - udcy = -udcx * udx / udy
 * - -udcx * (udx ** 2) / udy - udy * udcx = sqrt((1 - udl2) * udl2)
 * - -udcx * ((udx ** 2) / udy + udy) = sqrt((1 - udl2) * udl2)
 * - udcx = -sqrt((1 - udl2) * udl2) / ((udx ** 2) / udy + udy)
 * or
 * - udcx = -udcy * udy / udx
 * - udx * udcy + udcy * (udy ** 2) / udx = sqrt((1 - udl2) * udl2)
 * - udcy * (udx + (udy ** 2) / udx) = sqrt((1 - udl2) * udl2)
 * - udcy = sqrt((1 - udl2) * udl2) / (udx + (udy ** 2) / udx)
 *
 * - cx = rx * ucx
 * - cx = rx * (udcx + umx)
 * - cy = ry * ucy
 * - cy = ry * (udcy + umy)
 */
static int _calc_center(co_aix x0, co_aix y0,
		       co_aix x, co_aix y,
		       co_aix rx, co_aix ry,
		       co_aix x_rotate,
		       int large, int sweep,
		       co_aix *cx, co_aix *cy) {
    co_aix nrx, nry, nrx0, nry0;
    co_aix udx, udy, udx2, udy2;
    co_aix umx, umy;
    co_aix udcx, udcy;
    co_aix nrcx, nrcy;
    co_aix udl2;
    float _sin = sinf(x_rotate);
    float _cos = cosf(x_rotate);
    int reflect;
    
    /* Compute center of the ellipse */
    nrx = x * _cos + y * _sin;
    nry = x * -_sin + y * _cos;
    nrx0 = x0 * _cos + y0 * _sin;
    nry0 = x0 * -_sin + y0 * _cos;
    
    udx = (nrx - nrx0) / 2 / rx; /* ux - umx */
    udy = (nry - nry0) / 2 / ry; /* uy - umy */
    umx = (nrx + nrx0) / 2 / rx;
    umy = (nry + nry0) / 2 / ry;

    udx2 = udx * udx;
    udy2 = udy * udy;
    udl2 = udx2 + udy2;

    if(udy != 0) {
	/* center is at left-side of arc */
	udcx = -sqrtf((1 - udl2) * udl2) / (udy + udx2 / udy);
	udcy = -udcx * udx / udy;
    } else {
	/* center is at down-side of arc */
	udcx = 0;
	udcy = sqrtf((1 - udl2) * udl2) / udx;
    }

    reflect = 0;
    if(large)
	reflect ^= 1;
    if(sweep != 1)
	reflect ^= 1;
    if(reflect) {
	udcx = -udcx;
	udcy = -udcy;
    }

    nrcx = rx * (udcx + umx);
    nrcy = ry * (udcy + umy);

    *cx = nrcx * _cos - nrcy * _sin;
    *cy = nrcx * _sin + nrcy * _cos;

    return OK;
}


static co_aix _angle_rotated_ellipse(co_aix x, co_aix y,
				     co_aix rx, co_aix ry,
				     co_aix x_rotate) {
    co_aix nrx, nry;
    co_aix _sin, _cos;
    co_aix xy_tan;
    co_aix angle;

    _sin = sinf(x_rotate);
    _cos = cosf(x_rotate);

    nrx = (x * _cos + y * _sin) / rx;
    nry = (-x * _sin + y * _cos) / ry;
    xy_tan = nry / nrx;
    
    angle = atan(xy_tan);

    if(nrx < 0)
	angle = PI + angle;
    
    return angle;
}

static void _rotate(co_aix *x, co_aix *y, co_aix _sin, co_aix _cos) {
    co_aix nx, ny;

    nx = *x * _cos - *y * _sin;
    ny = *x * _sin + *y * _cos;

    *x = nx;
    *y = ny;
}

#define TAKE_NUM(r) do {			\
	SKIP_SPACE(p);				\
	old = p;				\
	SKIP_NUM(p);				\
	if(p == old)				\
	    return ERR;				\
	r = atof(old);				\
    } while(0);

static int _sh_path_arc_cmd_arg_fill(char cmd, char **cmds_p,
				     const char **data_p,
				     co_aix **pnts_p,
				     co_aix **float_args_p) {
    co_aix rx, ry;
    co_aix x_rotate;
    int large, sweep;
    co_aix x, y, x0, y0, cx, cy;
    co_aix corners[4][2];
    co_aix angle_start, angle_stop;
    co_aix *pnts = *pnts_p;
    const char *old;
    const char *p;
    char *cmds;
    co_aix *float_args;
    co_aix _sin, _cos;
    int i;

    p = *data_p;
    cmds = *cmds_p;
    float_args = *float_args_p;
    while(*p) {
	SKIP_SPACE(p);
	old = p;
	SKIP_NUM(p);
	if(p == old)
	    break;
	rx = atof(old);

	TAKE_NUM(ry);
	TAKE_NUM(x_rotate);
	TAKE_NUM(large);
	TAKE_NUM(sweep);
	TAKE_NUM(x);
	TAKE_NUM(y)

	x0 = *(pnts - 2);
	y0 = *(pnts - 1);

	if(islower(cmd)) {
	    x += x0;
	    y += y0;
	}

	_calc_center(x0, y0, x, y, rx, ry, x_rotate, large,
		     sweep, &cx, &cy);

	/* Compute positions for four corners.
	 * These four corners form a bounding box for the arc.
	 */
	_sin = sinf(x_rotate);
	_cos = cosf(x_rotate);
	corners[0][0] = -rx;
	corners[0][1] = -ry;
	corners[1][0] = rx;
	corners[1][1] = -ry;
	corners[2][0] = rx;
	corners[2][1] = ry;
	corners[3][0] = -rx;
	corners[3][1] = ry;
	for(i = 0; i < 4; i++) {
	    _rotate(&corners[i][0], &corners[i][1], _sin, _cos);
	    *pnts++ = corners[i][0] + cx;
	    *pnts++ = corners[i][1] + cy;
	}
	
	*(pnts++) = x;
	*(pnts++) = y;

	angle_start = _angle_rotated_ellipse(x0 - cx, y0 - cy,
					     rx, ry, x_rotate);
	angle_stop = _angle_rotated_ellipse(x - cx, y - cy,
					    rx, ry, x_rotate);

	if(sweep && angle_start > angle_stop)
	    angle_stop += 2 * PI;
	else if((!sweep) && angle_start < angle_stop)
	    angle_start += 2 * PI;
	
	*float_args++ = cx;
	*float_args++ = cy;
	*float_args++ = rx;
	*float_args++ = ry;
	*float_args++ = angle_start;
	*float_args++ = angle_stop;
	*float_args++ = x_rotate;
	
	*cmds++ = toupper(cmd);
    }

    *data_p = p;
    *pnts_p = pnts;
    *cmds_p = cmds;
    *float_args_p = float_args;

    return OK;
}

#define INNER(x1, y1, x2, y2) ((x1) * (x2) + (y1) * (y2))
#define CROSS(x1, y1, x2, y2) ((x1) * (y2) - (y1) * (x2))

static co_aix distance_pow2(co_aix x, co_aix y) {
    return x * x + y * y;
}

static co_aix angle_diff(co_aix sx, co_aix sy, co_aix dx, co_aix dy) {
    co_aix inner, cross;
    co_aix angle;
    co_aix rd2, rd;

    rd2 = distance_pow2(dx, dy);
    rd = sqrtf(rd2);
    
    inner = INNER(sx, sy, dx, dy);
    cross = CROSS(sx, sy, dx, dy);
    angle = acos(inner / rd);
    if(cross < 0)
	angle = 2 * PI - angle;

    return angle;
}

/*! \brief Make path for arcs in a path.
 */
void _sh_path_arc_path(mbe_t *cr, sh_path_t *path, const co_aix **pnts_p,
		       const co_aix **float_args_p) {
    co_aix cx, cy, x0, y0, x, y;
    co_aix rx, ry;
    co_aix xyratio;
    co_aix angle_start, angle_stop;
    co_aix x_rotate;
    const co_aix *pnts;
    const co_aix *float_args;
    co_aix matrix[6];
    co_aix dev_matrix[6];
    co_aix *aggr;
    co_aix _sin, _cos;

    pnts = *pnts_p;
    float_args = *float_args_p;
    x0 = *(pnts - 2);
    y0 = *(pnts - 1);
    pnts += 8;
    x = *pnts++;
    y = *pnts++;

    cx = *float_args++;
    cy = *float_args++;
    rx = *float_args++;
    ry = *float_args++;
    angle_start = *float_args++;
    angle_stop = *float_args++;
    x_rotate = *float_args++;

    _sin = sinf(x_rotate);
    _cos = cosf(x_rotate);
    
    xyratio = ry / rx;
    aggr = sh_get_aggr_matrix((shape_t *)path);
    matrix[0] = _cos;
    matrix[1] = -_sin * xyratio;
    matrix[2] = cx;
    matrix[3] = _sin;
    matrix[4] = _cos * xyratio;
    matrix[5] = cy;

    matrix_mul(aggr, matrix, dev_matrix);
    mbe_save(cr);
    mbe_transform(cr, dev_matrix);
    mbe_arc(cr, 0, 0, rx, angle_start, angle_stop); 
    mbe_restore(cr);

    *pnts_p = pnts;
    *float_args_p = float_args;
}

/* ============================================================ */

static void sh_path_free(shape_t *shape) {
    sh_path_t *path = (sh_path_t *)shape;
    if(path->user_data)
	free(path->user_data);
    free(path);
}

/*! \brief Count number of arguments.
 *
 * \todo Notify programmers that syntax or value error of path data.
 */
static int sh_path_cmd_arg_cnt(char *data, int *cmd_cntp, int *pnt_cntp,
			       int *float_arg_cntp) {
    char *p, *old;
    int cmd_cnt, pnt_cnt, float_arg_cnt;
    int i;

    cmd_cnt = pnt_cnt = float_arg_cnt = 0;
    p = data;
    SKIP_SPACE(p);
    while(*p) {
	switch(*p++) {
	case 'c':
	case 'C':
	    while(*p) {
		old = p;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		cmd_cnt++;
	    }
	    break;
	case 's':
	case 'S':
	case 'q':
	case 'Q':
	    while(*p) {
		old = p;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		cmd_cnt++;
	    }
	    break;
	case 'm':
	case 'M':
	case 'l':
	case 'L':
	case 't':
	case 'T':
	    while(*p) {
		old = p;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		pnt_cnt++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		pnt_cnt++;

		cmd_cnt++;
	    }
	    break;
	case 'h':
	case 'H':
	case 'v':
	case 'V':
	    while(*p) {
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		pnt_cnt += 2;

		cmd_cnt++;
	    }
	    break;
	case 'A':
	case 'a':
	    while(*p) {
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		
		for(i = 0; i < 6; i++) {
		    SKIP_SPACE(p);
		    old = p;
		    SKIP_NUM(p);
		    if(p == old)
			return ERR;
		}

		pnt_cnt += 10;
		float_arg_cnt += 7;

		cmd_cnt++;
	    }
	    break;
	case 'z':
	case 'Z':
	    cmd_cnt++;
	    break;
	default:
	    return ERR;
	}
	/*! \todo cmd_cnt should be increased for each implicit repeating. */
	SKIP_SPACE(p);
    }

    *cmd_cntp = cmd_cnt;
    *pnt_cntp = pnt_cnt;
    *float_arg_cntp = float_arg_cnt;
    return OK;
}

#define TO_ABSX islower(cmd)? x + atof(old): atof(old)
#define TO_ABSY islower(cmd)? y + atof(old): atof(old)

static int sh_path_cmd_arg_fill(char *data, sh_path_t *path) {
    char *p, *old;
    char *cmds;
    char cmd;
    co_aix *pnts;
    co_aix *float_args;
    co_aix x, y;
    int r;

    cmds = path->user_data;
    pnts = (co_aix *)(cmds + path->cmd_len);
    float_args = (co_aix *)(cmds + path->cmd_len +
			    path->pnt_len * sizeof(co_aix));
    p = data;
    SKIP_SPACE(p);
    while(*p) {
	/* Transform all relative to absolute, */
	x = *(pnts - 2);
	y = *(pnts - 1);

	switch((cmd = *p++)) {
	case 'c':
	case 'C':
	    while(*p) {
		old = p;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		*pnts = TO_ABSX;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSY;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSX;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSY;
		pnts++;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSX;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSY;
		pnts++;

		*cmds++ = toupper(cmd);
	    }
	    break;
	case 's':
	case 'S':
	case 'q':
	case 'Q':
	    while(*p) {
		old = p;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		*pnts = TO_ABSX;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSY;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSX;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSY;
		pnts++;

		*cmds++ = toupper(cmd);
	    }
	    break;
	case 'm':
	case 'M':
	case 'l':
	case 'L':
	case 't':
	case 'T':
	    while(*p) {
		old = p;
		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    break;
		*pnts = TO_ABSX;
		pnts++;

		SKIP_SPACE(p);
		old = p;
		SKIP_NUM(p);
		if(p == old)
		    return ERR;
		*pnts = TO_ABSY;
		pnts++;

		*cmds++ = toupper(cmd);
	    }
	    break;
	case 'h':
	case 'H':
	case 'v':
	case 'V':
	    /*! \todo implement h, H, v, V comamnds for path. */
	    return ERR;

	case 'A':
	case 'a':
	    r = _sh_path_arc_cmd_arg_fill(cmd, &cmds,
					  (const char **)&p, &pnts,
					  &float_args);
	    if(r != OK)
		return ERR;
	    break;

	case 'z':
	case 'Z':
	    *cmds++ = toupper(cmd);
	    break;
	default:
	    return ERR;
	}
	SKIP_SPACE(p);
    }

    return OK;
}

/*! \brief Create a path from value of 'data' of SVG path.
 */
shape_t *rdman_shape_path_new(redraw_man_t *rdman, char *data) {
    sh_path_t *path;
    int cmd_cnt, pnt_cnt, float_arg_cnt;
    int msz;
    int r;

    r = sh_path_cmd_arg_cnt(data, &cmd_cnt, &pnt_cnt,
			    &float_arg_cnt);
    if(r == ERR)
	return NULL;

    /* Align at 4's boundary and keep 2 unused co_aix space
     * to make logic of transformation from relative to absolute
     * simple.
     */
    cmd_cnt += RESERVED_AIXS;
    cmd_cnt = (cmd_cnt + 3) & ~0x3;

    /*! \todo Use elmpool to manage sh_path_t objects. */
    path = (sh_path_t *)malloc(sizeof(sh_path_t));
    /*! \todo Remove this memset()? */
    memset(&path->shape, 0, sizeof(shape_t));
    mb_obj_init(path, MBO_PATH);
    path->cmd_len = cmd_cnt;
    path->pnt_len = pnt_cnt;
    path->float_arg_len = float_arg_cnt;

    msz = cmd_cnt + sizeof(co_aix) * pnt_cnt +
	sizeof(co_aix) * float_arg_cnt;
    path->user_data = (char *)malloc(msz * 2);
    if(path->user_data == NULL) {
	free(path);
	return NULL;
    }

    path->dev_data = path->user_data + msz;

    r = sh_path_cmd_arg_fill(data, path);
    if(r == ERR) {
	free(path->user_data);
	free(path);
	return NULL;
    }
    memcpy(path->dev_data, path->user_data, msz);

    path->shape.free = sh_path_free;

    rdman_shape_man(rdman, (shape_t *)path);

    return (shape_t *)path;
}

shape_t *rdman_shape_path_new_from_binary(redraw_man_t *rdman,
					  char *commands,
					  co_aix *pnts, int pnt_cnt,
					  co_aix *float_args,
					  int float_arg_cnt) {
    sh_path_t *path;
    int msz;
    int cmd_cnt = strlen(commands);

    /*! \todo Use elmpool to manage sh_path_t objects. */
    path = (sh_path_t *)malloc(sizeof(sh_path_t));
    /*! \todo Remove this memset()? */
    memset(&path->shape, 0, sizeof(shape_t));
    mb_obj_init(path, MBO_PATH);
    cmd_cnt = (cmd_cnt + 3) & ~0x3;
    path->cmd_len = cmd_cnt;
    path->pnt_len = pnt_cnt;
    path->float_arg_len = float_arg_cnt;
    msz = cmd_cnt + sizeof(co_aix) * pnt_cnt +
	sizeof(co_aix) * float_arg_cnt;
    path->user_data = (char *)malloc(msz * 2);
    if(path->user_data == NULL) {
	free(path);
	return NULL;
    }

    path->dev_data = path->user_data + msz;
    memcpy(path->user_data, commands, strlen(commands));
    memcpy(path->user_data + cmd_cnt, pnts, sizeof(co_aix) * pnt_cnt);
    memcpy(path->user_data + cmd_cnt + pnt_cnt * sizeof(co_aix),
	   float_args, sizeof(co_aix) * float_arg_cnt);
    memcpy(path->dev_data, path->user_data, msz);
    
    path->shape.free = sh_path_free;
    
    rdman_shape_man(rdman, (shape_t *)path);

    return (shape_t *)path;
}


/*! \brief Transform a path from user space to device space.
 *
 */
void sh_path_transform(shape_t *shape) {
    sh_path_t *path;
    co_aix *pnts, *dev_pnts;
    co_aix (*poses)[2];
    area_t *area;
    int pnt_len;
    int i;

    ASSERT(shape->type == SHT_PATH);
    ASSERT((shape->pnt_len & 0x1) == 0);

    path = (sh_path_t *)shape;
    pnts = (co_aix *)(path->user_data + path->cmd_len);
    dev_pnts = (co_aix *)(path->dev_data + path->cmd_len);
    pnt_len = path->pnt_len;
    for(i = 0; i < pnt_len; i += 2) {
	dev_pnts[0] = *pnts++;
	dev_pnts[1] = *pnts++;
	coord_trans_pos(shape->coord, dev_pnts, dev_pnts + 1);
	dev_pnts += 2;
    }

    if(path->shape.geo) {
	poses = (co_aix (*)[2])(path->dev_data + path->cmd_len);
	geo_from_positions(path->shape.geo, pnt_len / 2, poses);
	area = shape->geo->cur_area;
	area->x -= shape->stroke_width / 2 + 0.5;
	area->y -= shape->stroke_width / 2 + 0.5;
	area->w += shape->stroke_width + 1;
	area->h += shape->stroke_width + 1;
    }
}

static void sh_path_path(shape_t *shape, mbe_t *cr) {
    sh_path_t *path;
    int cmd_len;
    char *cmds, cmd;
    const co_aix *pnts;
    const co_aix *float_args;
    co_aix x, y, x1, y1, x2, y2;
    int i;

    ASSERT(shape->type == SHT_PATH);

    path = (sh_path_t *)shape;
    cmd_len = path->cmd_len;
    cmds = path->dev_data;
    pnts = (co_aix *)(cmds + cmd_len);
    float_args = (co_aix *)(cmds + cmd_len + path->pnt_len * sizeof(co_aix));
    x = y = x1 = y1 = x2 = y2 = 0;
    for(i = 0; i < cmd_len; i++) {
	/* All path commands and arguments are transformed
	 * to absoluted form.
	 */
	cmd = *cmds++;
	switch(cmd) {
	case 'M':
	    x = *pnts++;
	    y = *pnts++;
	    mbe_move_to(cr, x, y);
	    break;
	case 'L':
	    x = *pnts++;
	    y = *pnts++;
	    mbe_line_to(cr, x, y);
	    break;
	case 'C':
	    x1 = *pnts++;
	    y1 = *pnts++;
	    x2 = *pnts++;
	    y2 = *pnts++;
	    x = *pnts++;
	    y = *pnts++;
	    mbe_curve_to(cr, x1, y1, x2, y2, x, y);
	    break;
	case 'S':
	    x1 = x + x - x2;
	    y1 = y + y - y2;
	    x2 = *pnts++;
	    y2 = *pnts++;
	    x = *pnts++;
	    y = *pnts++;
	    mbe_curve_to(cr, x1, y1, x2, y2, x, y);
	    break;
	case 'Q':
	    x1 = *pnts++;
	    y1 = *pnts++;
	    x2 = x1;
	    y2 = y1;
	    x = *pnts++;
	    y = *pnts++;
	    mbe_curve_to(cr, x1, y1, x2, y2, x, y);
	    break;
	case 'T':
	    x1 = x + x - x2;
	    y1 = y + y - y2;
	    x2 = x1;
	    y2 = y1;
	    x = *pnts++;
	    y = *pnts++;
	    mbe_curve_to(cr, x1, y1, x2, y2, x, y);
	    break;
	case 'A':
	    _sh_path_arc_path(cr, path, &pnts, &float_args);
	    break;
	case 'Z':
	    mbe_close_path(cr);
	    break;
	case '\x0':
	    i = cmd_len;	/* padding! Skip remain ones. */
	    break;
	}
    }
}

void sh_path_draw(shape_t *shape, mbe_t *cr) {
    sh_path_path(shape, cr);
}

#ifdef UNITTEST

#include <CUnit/Basic.h>

void test_rdman_shape_path_new(void) {
    sh_path_t *path;
    co_aix *pnts;

    path = (sh_path_t *)rdman_shape_path_new(NULL, "M 33 25l33 55c 33 87 44 22 55 99L33 77z");
    CU_ASSERT(path != NULL);
    CU_ASSERT(path->cmd_len == ((5 + RESERVED_AIXS + 3) & ~0x3));
    CU_ASSERT(path->pnt_len == 12);
    CU_ASSERT(strncmp(path->user_data, "MLCLZ", 5) == 0);
    CU_ASSERT(strncmp(path->dev_data, "MLCLZ", 5) == 0);

    pnts = (co_aix *)(path->user_data + path->cmd_len);
    CU_ASSERT(pnts[0] == 33);
    CU_ASSERT(pnts[1] == 25);
    CU_ASSERT(pnts[2] == 66);
    CU_ASSERT(pnts[3] == 80);
    CU_ASSERT(pnts[4] == 99);
    CU_ASSERT(pnts[5] == 167);
    CU_ASSERT(pnts[6] == 110);
    CU_ASSERT(pnts[7] == 102);
    CU_ASSERT(pnts[8] == 121);
    CU_ASSERT(pnts[9] == 179);
    CU_ASSERT(pnts[10] == 33);
    CU_ASSERT(pnts[11] == 77);
    sh_path_free((shape_t *)path);
}

void test_path_transform(void) {
    sh_path_t *path;
    co_aix *pnts;
    coord_t coord;
    geo_t geo;

    path = (sh_path_t *)rdman_shape_path_new(NULL, "M 33 25l33 55C 33 87 44 22 55 99L33 77z");
    CU_ASSERT(path != NULL);
    CU_ASSERT(path->cmd_len == ((5 + RESERVED_AIXS + 3) & ~0x3));
    CU_ASSERT(path->pnt_len == 12);
    CU_ASSERT(strncmp(path->user_data, "MLCLZ", 5) == 0);
    CU_ASSERT(strncmp(path->dev_data, "MLCLZ", 5) == 0);

    geo_init(&geo);
    path->shape.geo = &geo;
    geo.shape = (shape_t *)path;

    coord.aggr_matrix[0] = 1;
    coord.aggr_matrix[1] = 0;
    coord.aggr_matrix[2] = 1;
    coord.aggr_matrix[3] = 0;
    coord.aggr_matrix[4] = 2;
    coord.aggr_matrix[5] = 0;
    path->shape.coord = &coord;
    sh_path_transform((shape_t *)path);

    pnts = (co_aix *)(path->dev_data + path->cmd_len);
    CU_ASSERT(pnts[0] == 34);
    CU_ASSERT(pnts[1] == 50);
    CU_ASSERT(pnts[2] == 67);
    CU_ASSERT(pnts[3] == 160);
    CU_ASSERT(pnts[4] == 34);
    CU_ASSERT(pnts[5] == 174);
    CU_ASSERT(pnts[6] == 45);
    CU_ASSERT(pnts[7] == 44);
    CU_ASSERT(pnts[8] == 56);
    CU_ASSERT(pnts[9] == 198);
    CU_ASSERT(pnts[10] == 34);
    CU_ASSERT(pnts[11] == 154);

    sh_path_free((shape_t *)path);
}

void test_spaces_head_tail(void) {
    sh_path_t *path;

    path = (sh_path_t *)
	rdman_shape_path_new(NULL,
			     " M 33 25l33 55C 33 87 44 22 55 99L33 77z ");
    CU_ASSERT(path != NULL);
    sh_path_free((shape_t *)path);
}

CU_pSuite get_shape_path_suite(void) {
    CU_pSuite suite;

    suite = CU_add_suite("Suite_shape_path", NULL, NULL);
    CU_ADD_TEST(suite, test_rdman_shape_path_new);
    CU_ADD_TEST(suite, test_path_transform);

    return suite;
}

#endif /* UNITTEST */