vector/Vlib/copy.c

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/*!
  \file lib/vector/Vlib/copy.c
  
  \brief Vector library - Copy vector features and attribute tables linked to the map
  
  Higher level functions for reading/writing/manipulating vectors.
  
  (C) 2001-2009, 2012-2013 by the GRASS Development Team
  
  This program is free software under the GNU General Public License
  (>=v2). Read the file COPYING that comes with GRASS for details.
  
  \author Original author CERL, probably Dave Gerdes or Mike Higgins.
  \author Update to GRASS 5.7 Radim Blazek and David D. Gray.
  \author Update to GRASS 7 by Martin Landa <landa.martin gmail.com> (OGR/PostGIS topology support)
*/

#include <grass/vector.h>
#include <grass/glocale.h>

#include "local_proto.h"

/*!
  \brief Copy topological elements

  - simple features (None)
  - native topo (GRASS)
  - PostGIS Topo
*/
#define TOPO_NONE   -1
#define TOPO_NATIVE  1
#define TOPO_POSTGIS 2

#ifdef HAVE_POSTGRES
#include "pg_local_proto.h"
#endif

static int copy_lines_1(struct Map_info *, int, struct Map_info *);
static int copy_lines_2(struct Map_info *, int, int, struct Map_info *);
#if 0
static int copy_nodes(const struct Map_info *, struct Map_info *);
#endif
static int copy_line_nodes(const struct Map_info *, int, int, struct line_pnts *,
                           struct Map_info *);
static int is_isle(const struct Map_info *, int);

/*!
   \brief Copy all alive vector features from input vector map to
   output vector map

   \param In input vector map
   \param[out] Out output vector map

   \return 0 on success
   \return 1 on error
 */
int Vect_copy_map_lines(struct Map_info *In, struct Map_info *Out)
{
    return Vect_copy_map_lines_field(In, -1, Out);
}

/*!
   \brief Copy all alive vector features from given layer from input
   vector map to output vector map

   Note: Try to copy on level 2 otherwise level 1 is used.
   
   \param In input vector map
   \param field layer number (-1 for all layers)
   \param[out] Out output vector map

   \return 0 on success
   \return 1 on error
 */
int Vect_copy_map_lines_field(struct Map_info *In, int field,
                              struct Map_info *Out)
{
    int ret, format, topo;
    
    if (Vect_level(In) < 1)
        G_fatal_error(_("Unable to copy features. Input vector map <%s> is not open"),
                      Vect_get_full_name(In));

    format = Out->format; /* do not use Vect_maptype(), we need native
                             format for temporary maps here */
    topo = TOPO_NONE;
    if (format == GV_FORMAT_NATIVE) {
        topo = TOPO_NATIVE;
    }
    else if (format == GV_FORMAT_POSTGIS && Out->fInfo.pg.toposchema_name) {
        int type;
        
        topo = TOPO_POSTGIS;
        
        /* get type of first feature from input vector map */
        Vect_rewind(In);
        Vect_set_constraint_type(In, GV_POINTS | GV_LINES);
        type = Vect_read_next_line(In, NULL, NULL);
            
        /* create feature table with given feature type */
        if (0 > Vect_write_line(Out, type, NULL, NULL)) {
            G_warning(_("Unable to create PostGIS layer <%s>"),
                      Vect_get_finfo_layer_name(Out));
            return 1;
        }
    }
  
    /* Note: sometimes is important to copy on level 2 (pseudotopo
       centroids) and sometimes on level 1 if build take too long time
    */
    ret = 0;
    if (Vect_level(In) >= 2) {
        /* -> copy features on level 2 */
#if 0
        if (topo == TOPO_POSTGIS) {
            /* PostGIS topology - copy also nodes */
            copy_nodes(In, Out);
        }
#endif
        /* copy features */
        ret += copy_lines_2(In, field, topo, Out);

        if (topo == TOPO_NONE &&
            /* check output feature type, centroids can be exported as
             * points; boundaries as linestrings */
            strcmp(Vect_get_finfo_geometry_type(Out), "polygon") == 0) {
            /* copy areas - external formats and simple features access only */
            ret += Vect__copy_areas(In, field, Out);
        }
    }
    else {
        /* -> copy features on level 1 */
        if (topo == TOPO_NONE)
            G_warning(_("Vector map <%s> not open on topological level. "
                        "Areas will be skipped!"), Vect_get_full_name(In));
        
        ret += copy_lines_1(In, field, Out);
    }
    
    return ret > 0 ? 1 : 0;
}

/*!
  \brief Copy vector features on level 1

  \param In input vector map
  \param field layer number (-1 for all layers)
  \param Out output vector map
  
  \return 0 on success
  \return 1 on error
*/
int copy_lines_1(struct Map_info *In, int field, struct Map_info *Out)
{
    int ret, type;
    
    struct line_pnts *Points;
    struct line_cats *Cats;

    Points  = Vect_new_line_struct();
    Cats    = Vect_new_cats_struct();
    
    ret = 0;
    
    Vect_rewind(In);
    while (TRUE) {
        type = Vect_read_next_line(In, Points, Cats);
        if (type == -1) {
            G_warning(_("Unable to read vector map <%s>"),
                      Vect_get_full_name(In));
            ret = 1;
            break;
        }
        else if (type == -2) {      /* EOF */
            break;                  /* free allocated space and return */
        }
        else if (type == 0) {       /* dead line */
            continue;
        }
        
        /* don't skip boundaries if field != -1 */
        if (field != -1 && !(type & GV_BOUNDARY) &&
            Vect_cat_get(Cats, field, NULL) == 0)
            continue;       /* different layer */
        
        Vect_write_line(Out, type, Points, Cats);
    }

    Vect_destroy_line_struct(Points);
    Vect_destroy_cats_struct(Cats);

    return ret;
}

/*!
  \brief Copy vector features on level 2

  \param In input vector map
  \param field layer number (-1 for all layers)
  \param topo topo access (none, native, postgis)
  \param Out output vector map
  
  \return 0 on success
  \return 1 on error
*/
int copy_lines_2(struct Map_info *In, int field, int topo, struct Map_info *Out)
{
    int i, type, nlines, nskipped;
    int ret, left, rite, centroid, with_z;

    struct line_pnts *Points, *CPoints, *NPoints;
    struct line_cats *Cats, *CCats;

    const char *ftype = NULL;
    
    Points  = Vect_new_line_struct();
    CPoints = Vect_new_line_struct();
    NPoints = Vect_new_line_struct();
    Cats    = Vect_new_cats_struct();
    CCats   = Vect_new_cats_struct();
    
    with_z = Vect_is_3d(In);
    
    ret = 0;
    nlines = Vect_get_num_lines(In);
    if (topo == TOPO_NONE) {
        ftype = Vect_get_finfo_geometry_type(Out);
        G_debug(2, "feature type: %s", ftype ? ftype : "?");
        if (!ftype)
            G_message(_("Copying features..."));
        else 
            G_message(_("Copying features (%s)..."), ftype);
    }
    else
        G_message(_("Copying features..."));    
    
    Vect_append_point(NPoints, 0., 0., 0.);
    nskipped = 0;
    for (i = 1; i <= nlines; i++) {
        if (!Vect_line_alive(In, i))
            continue;
        
        G_percent(i, nlines, 2);
        type = Vect_read_line(In, Points, Cats, i);
        if (type == -1) {
            G_warning(_("Unable to read vector map <%s>"),
                      Vect_get_full_name(In));
            ret = 1;
            break;          /* free allocated space and return */
        }
        if (type == 0)
            continue;       /* dead line */
        if (In->constraint.type_flag) {
            /* skip feature by type */
            if (!(type & In->constraint.type))
                continue;
        }

        if (topo == TOPO_NONE) {
            /* OGR/PostGIS layers (simple features) */
            int skip = FALSE;
            
            if (type == GV_BOUNDARY)
                /* boundaries are written as linestrings when output
                 * feature type is defined as 'linestring', otherwise
                 * they are skipped */
                if (ftype && strcmp(ftype, "linestring") != 0)
                    skip = TRUE;

            /* centroids are stored in topo polygon defined by areas
               (topo required) */
            if (type == GV_CENTROID) {
                /* centroids are written as points when output feature
                 * type is defined as 'point', otherwise they are
                 * skipped */
                if (ftype && strcmp(ftype, "point") != 0)
                    skip = TRUE;
            }

            if (skip)
                continue;
        }

        /* don't skips boundaries if field != -1 */
        if (field != -1) {
            if (type & GV_BOUNDARY) {
                if (Vect_cat_get(Cats, field, NULL) == 0) {
                    int skip_bndry = TRUE;
                    
                    Vect_get_line_areas(In, i, &left, &rite);
                    if (left < 0)
                        left = Vect_get_isle_area(In, abs(left));
                    if (left > 0) {
                        if ((centroid =
                             Vect_get_area_centroid(In, left)) > 0) {
                            Vect_read_line(In, CPoints, CCats, centroid);
                            if (Vect_cat_get(CCats, field, NULL) != 0)
                                skip_bndry = FALSE;
                        }
                    }
                    if (skip_bndry) {
                        if (rite < 0)
                            rite = Vect_get_isle_area(In, abs(rite));
                        if (rite > 0) {
                            if ((centroid =
                                 Vect_get_area_centroid(In, rite)) > 0) {
                                Vect_read_line(In, CPoints, CCats,
                                               centroid);
                                if (Vect_cat_get(CCats, field, NULL) != 0)
                                    skip_bndry = FALSE;
                            }
                        }
                    }
                    if (skip_bndry)
                        continue;
                }
            }
            else if (Vect_cat_get(Cats, field, NULL) == 0) {
                nskipped++;
                continue;   /* different layer */
            }
        }
        
        /* copy also nodes connected to the line (PostGIS Topology
         * mode only) */
        if (topo == TOPO_POSTGIS && (type & GV_LINES)) {
            int n1, n2;
            
            struct P_line *Line;
            struct Format_info_offset *offset;
            
            offset = &(Out->fInfo.pg.offset);
            
            n1 = n2 = -1;
            Line = In->plus.Line[i];
            if (Line) {
                if (type == GV_LINE) {
                    struct P_topo_l *topo = (struct P_topo_l *)Line->topo;
                    
                    n1 = topo->N1;
                    n2 = topo->N2;
                }
                else if (type == GV_BOUNDARY) {
                    struct P_topo_b *topo = (struct P_topo_b *)Line->topo;
                    
                    n1 = topo->N1;
                    n2 = topo->N2;
                }
            }
                
            if (n1 > 0 && (n1 > offset->array_num || offset->array[n1-1] == 0)) 
                copy_line_nodes(In, n1, with_z, NPoints, Out);
            if (n2 > 0 && (n2 > offset->array_num || offset->array[n2-1] == 0))
                copy_line_nodes(In, n2, with_z, NPoints, Out);
        }

        if (-1 == Vect_write_line(Out, type, Points, Cats)) {
            G_warning(_("Writing new feature failed"));
            return 1;
        }
    }

    if (nskipped > 0)
        G_important_message(_("%d features without category or from different layer skipped"), nskipped);
    
    Vect_destroy_line_struct(Points);
    Vect_destroy_line_struct(CPoints);
    Vect_destroy_line_struct(NPoints);
    Vect_destroy_cats_struct(Cats);
    Vect_destroy_cats_struct(CCats);

    return ret;
}

#if 0
/*!
  \brief Copy nodes as points (PostGIS Topology only)

  \param In input vector map
  \param Out output vector map
  
  \return 0 on success
  \return 1 on error
*/
int copy_nodes(const struct Map_info *In, struct Map_info *Out)
{
    int nnodes, node, with_z;

    struct line_pnts *Points;

    Points  = Vect_new_line_struct();
    
    with_z = Vect_is_3d(In);
    
    nnodes = Vect_get_num_nodes(In);
    G_message(_("Exporting nodes..."));
    Vect_append_point(Points, 0., 0., 0.);
    for (node = 1; node <= nnodes; node++) {
        G_debug(3, "Exporting GRASS node %d", node);
        
        G_percent(node, nnodes, 5);
        copy_line_nodes(In, node, with_z, Points, Out);
    }
    
    Vect_destroy_line_struct(Points);

    return 0;
}
#endif

int copy_line_nodes(const struct Map_info *In, int node, int with_z,
                    struct line_pnts *Points, struct Map_info *Out)
{
    double x, y, z;
 
    Vect_get_node_coor(In, node, &x, &y, &z);
    Points->x[0] = x;
    Points->y[0] = y;
    if (with_z)
        Points->z[0] = z;
    
#ifdef HAVE_POSTGRES
    if (-1 == V2__write_node_pg(Out, Points)) {
        G_warning(_("Writing node %d failed"), node);
        return 1;
    }
#else
    G_fatal_error(_("GRASS is not compiled with PostgreSQL support"));
    return 1;
#endif

    return 0;
}

/*!
  \brief Check if area is part of an isle

  Check for areas that are part of isles which in turn are inside
  another area.

  \param Map pointer to Map_info struct
  \param area area id

  \return TRUE if area forms an isle otherwise FALSE
*/
int is_isle(const struct Map_info *Map, int area)
{
    int i, line, left, right, isle, is_isle;
    
    struct ilist *List;
    
    List = Vect_new_list();
    Vect_get_area_boundaries(Map, area, List);

    is_isle = FALSE;
    /* do we need to check all boundaries ? no */
    for (i = 0; i < List->n_values && !is_isle; i++) {
        line = List->value[i];
        if (1 != Vect_get_line_areas(Map, abs(line), &left, &right))
            continue;
        
        isle = line > 0 ? left : right;
        
        if (isle < 0 && Vect_get_isle_area(Map, abs(isle)) > 0) {
            is_isle = TRUE;
            break;
        }
    }

    G_debug(3, "is_isle(): area %d skip? -> %s", area, is_isle ? "yes" : "no");
    Vect_destroy_list(List);
    
    return is_isle;
}

/*!
  \brief Copy areas as polygons (OGR/PostGIS simple features access only)

  \param In input vector map
  \param field layer number (-1 for all layers)
  \param Out output vector map
  
  \return 0 on success
  \return 1 on error
*/
int Vect__copy_areas(const struct Map_info *In, int field, struct Map_info *Out)
{
    int i, area, nareas, cat, isle, nisles, nparts_alloc, nskipped;
    struct line_pnts **Points;
    struct line_cats *Cats;
    
    /* allocate points & cats */
    Points    = (struct line_pnts **) G_malloc(sizeof(struct line_pnts *));
    Points[0] = Vect_new_line_struct();
    nparts_alloc = 1;
    Cats      = Vect_new_cats_struct();

    /* copy areas */
    nskipped = 0;
    nareas = Vect_get_num_areas(In);
    if (nareas > 0)
        G_message(_("Exporting areas..."));
    for (area = 1; area <= nareas; area++) {
        G_debug(2, "area = %d", area);
        G_percent(area, nareas, 3);

        /* get category */
        Vect_reset_cats(Cats);
        if (field > 0) {
            cat = Vect_get_area_cat(In, area, field);
            /* skip area without category in given layer
            if (cat == -1) {
                nskipped++;
                continue; 
            }
            */

            if (cat > 0)
                Vect_cat_set(Cats, field, cat);
        }

        /* skip isles */
        if (Vect_get_area_centroid(In, area) == 0) {
            /* no centroid - check if area forms an isle */
            /* this check does not make sense because the area is also
             * not exported if it is part of an isle inside another
             * area: the isle gets exported as an inner ring
            if (!is_isle(In, area))
                G_warning(_("No centroid defined for area %d. "
                            "Area not exported."),
                          area);
            */
            G_debug(3, "Area %d: is_isle() -> %d", area, is_isle(In, area));
            continue;
        }
        
        /* get outer ring (area) */
        Vect_get_area_points(In, area, Points[0]);

        /* get inner rings (isles) */
        nisles = Vect_get_area_num_isles(In, area);
        if (nisles + 1 > nparts_alloc) {
            /* reallocate space for isles */
            Points = (struct line_pnts **) G_realloc(Points,
                                                     (nisles + 1) *
                                                     sizeof(struct line_pnts *));
            for (i = nparts_alloc; i < nisles + 1; i++)
                Points[i] = Vect_new_line_struct();
            nparts_alloc = nisles + 1;
        }
        G_debug(3, "\tcat=%d, nisles=%d", cat, nisles);
        for (i = 0; i < nisles; i++) {
            isle = Vect_get_area_isle(In, area, i);
            Vect_get_isle_points(In, isle, Points[i + 1]);
        }
        
        if (In != Out) {
            if (0 > V2__write_area_sfa(Out, (const struct line_pnts **) Points,
                                       nisles + 1, Cats)) {
                G_warning(_("Writing area %d failed"), area);
                return -1;
            }
        }
#ifdef HAVE_POSTGRES
        else { /* building simple features geometry from topogeometry data */
            if (0 > V2__update_area_pg(Out, (const struct line_pnts **) Points,
                                        nisles + 1, cat)) {
                G_warning(_("Writing area %d failed"), area);
                return -1;
            }
        }
#endif
    }

    if (nskipped > 0)
        G_important_message(_("%d areas without category or from different layer skipped"), nskipped);
    
    /* free allocated space for isles */
    for (i = 0; i < nparts_alloc; i++)
        Vect_destroy_line_struct(Points[i]);
    Vect_destroy_cats_struct(Cats);

    return 0;
}

/*!
   \brief Copy attribute tables linked to vector map.

   Copy all attribute tables linked to the vector map if
   <em>field</em> is 0, or selected attribute table defined by given
   field if <em>field</em> > 0.

   Notice, that if input vector map has no tables defined, it will
   copy nothing and return 0 (success).

   \param In input vector map
   \param[out] Out output vector map
   \param field layer number (0 for all tables linked to the vector map)

   \return 0 on success
   \return -1 on error
 */
int Vect_copy_tables(const struct Map_info *In, struct Map_info *Out,
                     int field)
{
    int i, n, type;
    struct field_info *Fi;

    n = Vect_get_num_dblinks(In);

    G_debug(2, "Vect_copy_tables(): copying %d tables", n);

    type = GV_1TABLE;
    if (field < 1 && n > 1)
        type = GV_MTABLE;

    for (i = 0; i < n; i++) {
        Fi = Vect_get_dblink(In, i);
        if (Fi == NULL) {
            G_warning(_("Database connection not defined for layer %d"),
                      In->dblnk->field[i].number);
            return -1;
        }
        if (field > 0 && Fi->number != field)
            continue;

        if (Vect_copy_table(In, Out, Fi->number, Fi->number, Fi->name,
                            type) != 0) {

            G_warning(_("Unable to copy table <%s> for layer %d from <%s> to <%s>"),
                        Fi->table, Fi->number, Vect_get_full_name(In), Vect_get_name(Out));
            return -1;
        }
    }

    return 0;
}

/*!
   \brief Copy attribute table linked to vector map based on type.

   \param In input vector map
   \param[out] Out output vector map
   \param field_in input layer number
   \param field_out output layer number
   \param field_name layer name (can be NULL)
   \param type how many tables are linked to map: GV_1TABLE / GV_MTABLE

   \return 0 on success
   \return -1 on error
 */
int Vect_copy_table(const struct Map_info *In, struct Map_info *Out, int field_in,
                    int field_out, const char *field_name, int type)
{
    return Vect_copy_table_by_cats(In, Out, field_in, field_out, field_name,
                                   type, NULL, 0);
}

/*!
   \brief Copy attribute table linked to vector map based on category
   list.

   If <em>cat_list</em> is NULL, then Vect_copy_table() is called.

   \param In input vector map
   \param[out] Out output vector map
   \param field_in input layer number
   \param field_out output layer number
   \param field_name layer name (can be NULL)
   \param type how many tables are linked to map: GV_1TABLE / GV_MTABLE
   \param cat_list pointer to cat_list struct (can be NULL)

   \return 0 on success
   \return -1 on error
*/
int Vect_copy_table_by_cat_list(const struct Map_info *In, struct Map_info *Out,
                                int field_in, int field_out, const char *field_name,
                                int type, const struct cat_list *cat_list)
{
    int *cats;
    int ncats, ret;

    if (cat_list) {
        if (Vect_cat_list_to_array(cat_list, &cats, &ncats) != 0)
            return -1;
        
        ret = Vect_copy_table_by_cats(In, Out, field_in, field_out, field_name,
                                      type, cats, ncats);
        
        G_free(cats);
    }
    else {
        ret = Vect_copy_table(In, Out, field_in, field_out, field_name,
                              type);
    }

    return ret;
}

/*!
   \brief Copy attribute table linked to vector map based on category
   numbers.

   \param In input vector map
   \param[out] Out output vector map
   \param field_in input layer number
   \param field_out output layer number
   \param field_name layer name (can be NULL)
   \param type how many tables are linked to map: GV_1TABLE / GV_MTABLE
   \param cats pointer to array of cats or NULL
   \param ncats number of cats in 'cats'

   \return 0 on success
   \return -1 on error
 */
int Vect_copy_table_by_cats(const struct Map_info *In, struct Map_info *Out,
                            int field_in, int field_out, const char *field_name,
                            int type, int *cats, int ncats)
{
    int ret;
    struct field_info *Fi, *Fin;
    const char *name, *key;
    dbDriver *driver;

    G_debug(2, "Vect_copy_table_by_cats(): field_in = %d field_out = %d", field_in,
            field_out);

    Fi = Vect_get_field(In, field_in);
    if (Fi == NULL) {
        G_warning(_("Database connection not defined for layer %d"),
                  field_in);
        return -1;
    }

    if (field_name != NULL)
        name = field_name;
    else
        name = Fi->name;

    Fin = Vect_default_field_info(Out, field_out, name, type);
    G_debug(3, "Copy drv:db:table '%s:%s:%s' to '%s:%s:%s'",
            Fi->driver, Fi->database, Fi->table, Fin->driver, Fin->database,
            Fin->table);

    ret =
        Vect_map_add_dblink(Out, Fin->number, Fin->name, Fin->table, Fi->key,
                            Fin->database, Fin->driver);
    if (ret == -1) {
        G_warning(_("Unable to add database link for vector map <%s>"),
                  Out->name);
        return -1;
    }

    if (cats)
        key = Fi->key;
    else
        key = NULL;

    ret = db_copy_table_by_ints(Fi->driver, Fi->database, Fi->table,
                                Fin->driver, Vect_subst_var(Fin->database,
                                                            Out), Fin->table,
                                key, cats, ncats);
    if (ret == DB_FAILED) {
        G_warning(_("Unable to copy table <%s>"), Fin->table);
        return -1;
    }

    driver = db_start_driver_open_database(Fin->driver,
                                           Vect_subst_var(Fin->database,
                                                            Out));

    if (!driver) {
        G_warning(_("Unable to open database <%s> with driver <%s>"),
                      Fin->database, Fin->driver);
        return -1;
    }

    /* do not allow duplicate keys */
    if (db_create_index2(driver, Fin->table, Fi->key) != DB_OK) {
        G_warning(_("Unable to create index"));
        return -1;
    }

    if (db_grant_on_table(driver, Fin->table, DB_PRIV_SELECT,
         DB_GROUP | DB_PUBLIC) != DB_OK) {
        G_warning(_("Unable to grant privileges on table <%s>"),
                      Fin->table);
        return -1;
    }

    db_close_database_shutdown_driver(driver);

    return 0;
}