/*  @(#)xtract_lines.c    1.0  9/29/89   
 *  created by:         R.L.Glenn, SCS
 *
 * Program will read vector line records, outputting lines
 * which match the user list of names/categories.
 * The resulting map attribute is arbitarily set to first category
 * of the user list or a user selected category number (cat_new).
 */

#include <string.h>
#include <stdlib.h>
#include <grass/gis.h>
#include <grass/Vect.h>
#include <grass/dbmi.h>

static int *cats_array;
static int ncats_array;

int cmp ( const void *pa, const void *pb)
{
    int *p1 = (int *) pa;
    int *p2 = (int *) pb;
    
    if( *p1 < *p2 ) return -1;
    if( *p1 > *p2 ) return 1;
    return 0;
}

/* check if cat is in list */
int in_list ( int cat ) 
{
    if ( bsearch ( &cat, cats_array, ncats_array, sizeof(int), cmp ) )
        return 1;

    return 0;
}

/* output reclass cats */
void extract_cats ( struct line_cats *Cats, int type_only, int field, int new )
{
    int i, tmp;
    static struct line_cats *TCats = NULL;

    if ( !TCats ) TCats = Vect_new_cats_struct ();

    /* Copy */
    Vect_reset_cats ( TCats );

    for ( i = 0; i < Cats->n_cats; i++ ) {
	Vect_cat_set ( TCats, Cats->field[i], Cats->cat[i] );
    }
    
    if ( type_only && field == -1 ) /* keep all */
    {	
	return;
    }
    else if ( type_only && field > 0 ) /* keep only one field */
    {
	Vect_reset_cats ( Cats );

	if ( new > -1 ) {
	    if ( Vect_cat_get( TCats,field,&tmp) ) 
		Vect_cat_set ( Cats, field, new );
	} else {
	    for ( i = 0; i < TCats->n_cats; i++ ) {
		if ( TCats->field[i] == field ) 
		    Vect_cat_set ( Cats, field, TCats->cat[i] );
	    }
	}
    }
    else /* keep only one field, cats in list */
    {
	Vect_reset_cats ( Cats );

	if ( new > -1 ) {
	    int found = 0;
	    
	    for ( i = 0; i < TCats->n_cats; i++ ) {
		if ( TCats->field[i] == field ) {
		    if ( in_list(TCats->cat[i]) ) {
			found = 1;
			break;
		    }
		}
	    }
	    if ( found )
		Vect_cat_set ( Cats, field, new );
	} else {
	    for ( i = 0; i < TCats->n_cats; i++ ) {
		if ( TCats->field[i] == field ) {
		    if ( in_list(TCats->cat[i]) ) {
		        Vect_cat_set ( Cats, field, TCats->cat[i] );
		    }
		}
	    }
	}

    }
}

/* check if output cats of left and right area match */
int areas_new_cats_match ( struct Map_info *In, int area1, int area2, int type_only, int field, int new ) 
{
    int i, j, found;
    int centroid1, centroid2;
    static struct line_cats *Cats1 = NULL;
    static struct line_cats *Cats2 = NULL;
	     
    G_debug ( 4, "areas_new_cats_match area1 = %d area2 = %d", area1, area2 );

    if ( !Cats1 ) Cats1 = Vect_new_cats_struct ();
    if ( !Cats2 ) Cats2 = Vect_new_cats_struct ();

    if ( area1 < 1 || area2 < 1 ) return 0; /* at least one area is missing */
    
    centroid1 = Vect_get_area_centroid ( In, area1 );
    centroid2 = Vect_get_area_centroid ( In, area2 );
    
    if ( centroid1 < 1 || centroid2 < 1 ) return 0; /* at least one centroid is missing */
	 
    Vect_read_line ( In, NULL, Cats1, centroid1);
    Vect_read_line ( In, NULL, Cats2, centroid2);

    extract_cats ( Cats1, type_only, field, new );
    extract_cats ( Cats2, type_only, field, new );

    if ( Cats1->n_cats != Cats2->n_cats ) return 0;
    
    for ( i = 0; i < Cats1->n_cats; i++ ) {
	found = 0;
        for ( j = 0; j < Cats2->n_cats; j++ ) {
            G_debug ( 5, "%d:%d x %d:%d", Cats1->field[i], Cats1->cat[i], Cats2->field[j], Cats2->cat[j] );
	    if ( Cats1->field[i] == Cats2->field[j] && Cats1->cat[i] == Cats2->cat[j] ) {
		found = 1;
		break;
	    }
	}
	if ( !found ) return 0;
    }

    G_debug ( 3, "match" );
    return 1;
}

int 
xtract_line (int num_index, int *num_array, struct Map_info *In, struct Map_info *Out,
             int new, int select_type, int dissolve, int field, int type_only)
{
        int line;
	struct line_pnts *Points;
	struct line_cats *Line_Cats_Old, *CCats;

        /* Initialize the Point structure, ONCE */
        Points = Vect_new_line_struct();
	Line_Cats_Old = Vect_new_cats_struct ();
	CCats = Vect_new_cats_struct ();

	cats_array = num_array;
	ncats_array = num_index;

	/* sort list */
	qsort ( cats_array, ncats_array, sizeof(int), cmp ); 
	
        /* Cycle through all lines */
        for ( line = 1; line <= Vect_get_num_lines ( In ); line++) {
	    int left_area=0, right_area=0; /* left/right area */
	    int left_field_match=0, right_field_match=0; /* left/right area field match conditions */
	    int left_cat_match=0, right_cat_match=0; /* left/right area cat match conditions */
	    int type_match=0;  /* line type match */
	    int field_match=0; /* category of field match */
	    int cat_match=0;   /* category found in list */
	    int centroid_in_area=0;   /* centroid is in area */
	    int type;
	    int i, tmp, write;
	    
	    G_debug ( 3, "Line = %d", line );

	     /* Get data */
	     type = Vect_read_line ( In, Points, Line_Cats_Old, line);
	     G_debug ( 3, "type = %d ncats = %d", type, Line_Cats_Old->n_cats);
	     
	     if ( type & select_type ) type_match = 1;

	     field_match = Vect_cat_get(Line_Cats_Old,field,&tmp);
	     
	     for ( i = 0; i < Line_Cats_Old->n_cats; i++ ) {
	         G_debug ( 3, "field = %d cat = %d", Line_Cats_Old->field[i], Line_Cats_Old->cat[i]);
		 if ( Line_Cats_Old->field[i] == field ) {
		     if ( in_list(Line_Cats_Old->cat[i]) ) {
			 cat_match = 1;
			 break;
		     }
		 }
	     }

	     if ( type == GV_BOUNDARY ) {
	         int centroid;
		 
		 Vect_get_line_areas ( In, line, &left_area, &right_area );

		 if ( left_area < 0 )
		    left_area = Vect_get_isle_area ( In, abs(left_area) ); 
		 if ( left_area > 0 ) {
		     centroid = Vect_get_area_centroid ( In, left_area );
		     if ( centroid > 0 ) {
			 Vect_read_line ( In, NULL, CCats, centroid);
			 left_field_match = Vect_cat_get(CCats,field,&tmp);
			 for ( i = 0; i < CCats->n_cats; i++ ) {
			     if ( CCats->field[i] == field ) {
				 if ( in_list(CCats->cat[i]) ) {
				     left_cat_match = 1;
				     break;
				 }
			     }
			 }
		     }
		 } 
		 
		 if ( right_area < 0 ) 
		    right_area = Vect_get_isle_area ( In, abs(right_area) ); 
		 if ( right_area > 0 ) {
		     centroid = Vect_get_area_centroid ( In, right_area );
		     if ( centroid > 0 ) {
			 Vect_read_line ( In, NULL, CCats, centroid);
			 right_field_match = Vect_cat_get(CCats,field,&tmp);
			 for ( i = 0; i < CCats->n_cats; i++ ) {
			     if ( CCats->field[i] == field ) {
				 if ( in_list(CCats->cat[i]) ) {
				     right_cat_match = 1;
				     break;
				 }
			     }
			 }
		     }
		 }
	     }

	     if ( type == GV_CENTROID ) {
		 int area;
		 
		 area = Vect_get_centroid_area ( In, line );
		 if ( area > 0 ) centroid_in_area = 1;
	     }
		 
	     G_debug ( 2, "type_match = %d field_match = %d cat_match = %d", type_match, field_match, cat_match );
	     G_debug ( 2, "left_area = %d left_field_match = %d left_cat_match = %d", 
		           left_area, left_field_match, left_cat_match );

	     G_debug ( 2, "right_area = %d right_field_match = %d right_cat_match = %d", 
		           right_area, right_field_match, right_cat_match );
	     
	     /* Check if the line match conditions */
	     write = 0;
	     if ( type_only && field == -1 ) /* type only */
	     {
		 /* line */
		 if ( type_match ) write = 1; 

		 /* centroid */
	         if ( type == GV_CENTROID && (select_type & GV_AREA) && centroid_in_area ) write = 1;

		 /* areas */ 
		 if ( type == GV_BOUNDARY && ( left_area || right_area ) ) {
		     if ( !dissolve || !areas_new_cats_match ( In, left_area, right_area, type_only, field, new ) )
		         write = 1;
		 }
	     }
	     else if ( type_only && field > 0 ) /* type and field only */
	     {
		 /* line */
		 if ( type_match && field_match ) write = 1; 

		 /* centroid */
	         if ( type == GV_CENTROID && (select_type & GV_AREA) && centroid_in_area && field_match ) write = 1;

		 /* areas */ 
		 if ( type == GV_BOUNDARY && (select_type & GV_AREA) && ( left_field_match || right_field_match ) ) {
		     if ( !dissolve || !areas_new_cats_match ( In, left_area, right_area, type_only, field, new ) )
		         write = 1;
		 }
	     } 
	     else  /* type, field and category */
	     {
		 /* line */
		 if ( type_match && cat_match ) write = 1; 

		 /* centroid */
	         if ( type == GV_CENTROID && (select_type & GV_AREA) && centroid_in_area && cat_match ) write = 1;

		 /* areas */ 
		 if ( type == GV_BOUNDARY && (select_type & GV_AREA) && ( left_cat_match || right_cat_match ) ) {
		     if ( !dissolve || !areas_new_cats_match ( In, left_area, right_area, type_only, field, new ) )
		         write = 1;
		 }
	     }
		 
	     G_debug ( 2, "write = %d", write );
		 
	    if ( write ) {
                 extract_cats ( Line_Cats_Old, type_only, field, new );

		 Vect_write_line (Out, type, Points, Line_Cats_Old);
	    }
		      
        }  /* end lines section */

	return(0) ;
}