#! /bin/sh

DB=${1:-geo}
REL=${2:-top_polys}
RESOL=${3:-1}

#
# We use nawk because we need the abs() function
# Use gawk (gnu-awk) if you have version 7 awk
#

nawk '
	{ print }
END	{ print "-1" }
' | nawk '

function abs(x) { if (x >= 0) return x; else return -x }

{
  if (old_fn == 0)
    old_fn= $1

  if ($1 != old_fn) {

    while (pcnt > 1) {

      split(pla[pcnt], coor, ",")
      nc= coor[1]
      xs= coor[2]; ys= coor[3]
      xe= coor[2*nc]; ye= coor[2*nc+1]
      cind= index(pla[pcnt], ",")
      subcoor= substr(pla[pcnt], cind+1)
      rsubcoor= xe "," ye
      for (i= nc-1; i >= 1; i--)
	rsubcoor= rsubcoor "," coor[2*i] "," coor[2*i+1]

      for (i= 1; i < pcnt; i++) {

#for (j= 1; j <= pcnt; j++) {
  #print pla[j]
#}
	split(pla[i], tcoor, ",")
	tnc= tcoor[1]
	txs= tcoor[2]; tys= tcoor[3]
	txe= tcoor[2*tnc]; tye= tcoor[2*tnc+1]
	cind= index(pla[i], ",")
	tsubcoor= substr(pla[i], cind+1)
#print "fn: " old_fn
#print "xs: " xs " ys: " ys
#print "xe: " xe " ye: " ye
#print "txs: " txs " tys: " tys
#print "txe: " txe " tye: " tye
#print "subcoor: " subcoor " rsubcoor: " rsubcoor " tsubcoor:" tsubcoor
	
	if (abs(xs-txe) <= '$RESOL' && abs(ys-tye) <= '$RESOL') {
	  newcoor= (nc + tnc) "," tsubcoor "," subcoor
	} else if (abs(xs-txs) <= '$RESOL' && abs(ys-tys) <= '$RESOL') {
	  newcoor= (nc + tnc) "," rsubcoor "," tsubcoor
	} else if (abs(xe-txs) <= '$RESOL' && abs(ye-tys) <= '$RESOL') {
	  newcoor= (nc + tnc) "," subcoor "," tsubcoor
	} else if (abs(xe-txe) <= '$RESOL' && abs(ye-tye) <= '$RESOL') {
	  newcoor= (nc + tnc) "," tsubcoor "," rsubcoor
	} else {
#printf "Not found\n"
	  continue;
	}

	pla[i]= newcoor
	pcnt--
	i= 0
#printf "Found\n"
	break;
      }

      if (i == pcnt) {
	printf "Inconsistent topology for feature: %d ! Exiting !\n", old_fn > "/dev/tty"
	exit
      }

    }

    nc= split(pla[1], cca, ",")
    xmin= 1e20; xmax= -1e20; ymin= xmin; ymax= xmax
    for (i= 2; i <= nc; i+= 2) {
	if (cca[i] < xmin)
	  xmin= cca[i]
	if (cca[i] > xmax)
	  xmax= cca[i]
	if (cca[i+1] < ymin)
	  ymin= cca[i+1]
	if (cca[i+1] > ymax)
	  ymax= cca[i+1]
    }

    printf "append '$REL' (centroid_fn= %d, ", old_fn
    printf "geo_bbox= \"(%f,%f,%f,%f)\", ", xmin, ymin, xmax, ymax
    printf "geo_pline = \"(1,"
    printf "%s)\") \\g\n", pla[1]

    pcnt= 0
    old_fn= $1
  }

  if ($1 == -1)
    exit

  nopar= substr($2, 4, length($2) - 4)
  nc= split(nopar, coor, ",")
  if (nc <= 3 || (nc == 5 && (abs(coor[2]-coor[nc-1]) <= '$RESOL' \
  && abs(coor[3]-coor[nc]) <= '$RESOL'))) {
    printf "Bad line! Feat_num: %d\n", old_fn > "/dev/tty"
    printf "Line: %s\n", $2 > "/dev/tty"
    next
  }
  pcnt++
  pla[pcnt]= nopar
}
' | monitor $DB