/* Copyright (C) 2001-2007 Peter Selinger.
 *  This file is part of Potrace. It is free software and it is covered
 *  by the GNU General Public License. See the file COPYING for details. */

/* $Id: curve.c 147 2007-04-09 00:44:09Z selinger $ */
/* private part of the path and curve data structures */

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

#include "potracelib.h"
#include "lists.h"
#include "curve.h"

#define SAFE_MALLOC( var, n, typ ) \
    if( ( var = (typ*) malloc( (n)* sizeof(typ) ) ) == NULL ) \
             goto malloc_error

/* ---------------------------------------------------------------------- */
/* allocate and free path objects */

path_t* path_new( void )
{
    path_t*     p    = NULL;
    privpath_t* priv = NULL;

    SAFE_MALLOC( p, 1, path_t );
    memset( p, 0, sizeof(path_t) );
    SAFE_MALLOC( priv, 1, privpath_t );
    memset( priv, 0, sizeof(privpath_t) );
    p->priv = priv;
    return p;

malloc_error:
    free( p );
    free( priv );
    return NULL;
}


/* free the members of the given curve structure. Leave errno unchanged. */
static void privcurve_free_members( privcurve_t* curve )
{
    free( curve->tag );
    free( curve->c );
    free( curve->vertex );
    free( curve->alpha );
    free( curve->alpha0 );
    free( curve->beta );
}


/* free a path. Leave errno untouched. */
void path_free( path_t* p )
{
    if( p )
    {
        if( p->priv )
        {
            free( p->priv->pt );
            free( p->priv->lon );
            free( p->priv->sums );
            free( p->priv->po );
            privcurve_free_members( &p->priv->curve );
            privcurve_free_members( &p->priv->ocurve );
        }
        free( p->priv );
        /* do not free p->fcurve ! */
    }
    free( p );
}


/* free a pathlist, leaving errno untouched. */
void pathlist_free( path_t* plist )
{
    path_t* p;

    list_forall_unlink( p, plist ) {
        path_free( p );
    }
}


/* ---------------------------------------------------------------------- */
/* initialize and finalize curve structures */

typedef dpoint_t dpoint3_t[3];

/* initialize the members of the given curve structure to size m.
 *  Return 0 on success, 1 on error with errno set. */
int privcurve_init( privcurve_t* curve, int n )
{
    memset( curve, 0, sizeof(privcurve_t) );
    curve->n = n;
    SAFE_MALLOC( curve->tag, n, int );
    SAFE_MALLOC( curve->c, n, dpoint3_t );
    SAFE_MALLOC( curve->vertex, n, dpoint_t );
    SAFE_MALLOC( curve->alpha, n, double );
    SAFE_MALLOC( curve->alpha0, n, double );
    SAFE_MALLOC( curve->beta, n, double );
    return 0;

malloc_error:
    free( curve->tag );
    free( curve->c );
    free( curve->vertex );
    free( curve->alpha );
    free( curve->alpha0 );
    free( curve->beta );
    return 1;
}


/* copy private to public curve structure */
void privcurve_to_curve( privcurve_t* pc, potrace_curve_t* c )
{
    c->n   = pc->n;
    c->tag = pc->tag;
    c->c   = pc->c;
}
